10-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2021

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                  to                 

Commission file number 001-39425

Checkmate Pharmaceuticals, Inc.

(Exact name of registrant as specified in its charter)

Delaware	36-4813934
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification No.)
245 Main Street, 2nd Floor Cambridge, MA	02142
(Address of Principal Executive Offices)	(Zip Code)

Registrant’s telephone number, including area code: (617) 682-3625

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, par value  $0.0001 per share	CMPI	The Nasdaq Global Select Market

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ☐    No  ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ☐    No  ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  ☒    No  ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  ☒    No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer, “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer	☐	Accelerated filer	☒
Non-accelerated filer	☒	Smaller reporting company	☒
		Emerging growth company	☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Indicate by checkmark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.  ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ☐    No  ☒

The aggregate market value of the registrant’s common stock held by non-affiliates of the registrant as $124,028,535 as of June 30, 2021 (based on a closing price of $ 5.96 per share as quoted by the Nasdaq Global Select Market as of such date). In determining the market value of non-affiliate common stock, shares of the registrant’s common stock beneficially owned by officers, directors and affiliates have been excluded. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

As of March 29, 2022, the total number of shares outstanding of the registrant’s Common Stock was 21,630,627 shares.

Documents Incorporated by Reference:

Part III of this Annual Report on Form 10-K incorporates by reference certain information from the registrant’s definitive Proxy Statement for its 2022 annual meeting of shareholders, which the registrant intends to file pursuant to Regulation 14A with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year end of December 31, 2021. Except with respect to information specifically incorporated by reference in this Form 10-K, the Proxy Statement is not deemed to be filed as part of this Form 10-K.

TABLE OF CONTENTS

		Page
PART I
Item 1.	Business		7
Item 1A.	Risk Factors		42
Item 1B.	Unresolved Staff Comments		105
Item 2.	Properties		105
Item 3.	Legal Proceedings		105
Item 4.	Mine Safety Disclosures		105
PART II
Item 5.	Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities		106
Item 6.	Reserved		107
Item 7.	Management’s Discussion and Analysis of Financial Condition and Results of Operations		107
Item 7A.	Quantitative and Qualitative Disclosures about Market Risk		119
Item 8.	Financial Statements and Supplementary Data		120
Item 9.	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure		120
Item 9A.	Controls and Procedures		120
Item 9B.	Other Information		121
Item 9C.	Disclosure Regarding Foreign Jurisdictions that Prevent Inspections		121
PART III
Item 10.	Directors, Executive Officers and Corporate Governance		121
Item 11.	Executive Compensation		121
Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters		122
Item 13.	Certain Relationships and Related Transactions, and Director Independence		122
Item 14.	Principal Accounting Fees and Services		122
PART IV
Item 15.	Exhibits, Financial Statement Schedules		122
Item 16	Form 10-K Summary		122

2

SUMMARY OF THE MATERIAL RISKS ASSOCIATED WITH OUR BUSINESS

• We are a clinical-stage biopharmaceutical company with a limited operating history. We have incurred net losses since our inception and anticipate that we will continue to incur substantial and increasing net losses in the foreseeable future. We may never achieve or sustain profitability.

• A pandemic, epidemic, or outbreak of an infectious disease, such as the global novel coronavirus disease 2019 (“COVID-19”) pandemic, has, and may in the future, materially and adversely affect our business, including our preclinical studies, clinical trials, third-parties on whom we rely, our supply chain, our ability to raise capital, and our financial results.

• We have never generated any revenue from product sales, and our ability to generate revenue from product sales and become profitable will depend significantly on our success in achieving a number of goals and on other factors.

• We require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate all or a significant portion of our research and product development efforts, including one or more of our clinical trials.

• There are substantial doubts about our ability to continue as a going concern. Our ability to continue as a going concern requires that we obtain sufficient funding to finance our operations.

• We are heavily dependent on the success of vidutolimod (formerly CMP-001), our only current product candidate.

• We will not be able to commercialize vidutolimod and future product candidates if our preclinical studies do not produce successful results and our clinical trials do not demonstrate the safety and efficacy of vidutolimod and future product candidates.

• Vidutolimod is based on a novel approach to the treatment of cancer, which makes it difficult to predict the time and cost of product candidate development.

• Difficulty in enrolling patients has caused delays to our ongoing clinical trials of vidutolimod and could further delay ongoing trials or prevent or delay other clinical trials for vidotolimud or future product candidates. We have had difficulty enrolling patients due primarily to the COVID-19 pandemic, and may continue to find it difficult to enroll patients in our ongoing clinical trials or any subsequent trials that we may conduct.

• Vidutolimod is being, and future product candidates may be, evaluated in combination with third-party drugs, and we do not have control over the supply, regulatory status, or regulatory approval of such drugs.

• We currently rely on third-party contract manufacturing organizations (“CMOs”) for the production of clinical supply of vidutolimod and may rely on CMOs for the production of commercial supply of vidutolimod, if approved. This reliance on CMOs increases the risk that we will not have sufficient quantities of such materials, product candidates, or any therapies that we may develop and commercialize, or that such supply will not be available to us at an acceptable cost, which could delay, prevent, or impair our development or commercialization efforts.

• We rely, and expect to continue to rely, on third parties to conduct, supervise, and monitor our preclinical studies and clinical trials. If those third parties do not perform satisfactorily, we may be unable to obtain regulatory approval for vidutolimod or any future product candidates or any approvals that may be obtained may be delayed.

• Our collaboration agreements with any future third-parties may not be successful, which could adversely affect our ability to develop and commercialize vidutolimod or any future product candidates.

3

• The regulatory approval processes of the U.S. Food and Drug Administration (the “FDA”) and comparable foreign regulatory authorities are lengthy, time consuming and inherently unpredictable. If we are not able to obtain, or experience delays in obtaining, required regulatory approvals, we will not be able to commercialize vidutolimod and future product candidates as expected, and our ability to generate revenue may be materially impaired or eliminated.

• Our relationships with patients and third-party payors will be subject to applicable anti-kickback, fraud and abuse and other healthcare laws and regulations, which could expose us to criminal sanctions, civil penalties, exclusion from government healthcare programs, contractual damages, reputational harm and diminished profits and future earnings.

• We face significant competition, which may result in others discovering, developing or commercializing products more quickly or marketing them more successfully than us. If competitive product candidates are shown to be safer or more effective than ours, our commercial opportunity may be reduced or eliminated.

• If we are unable to obtain, maintain and protect our intellectual property rights for our technology and our product candidates, or if our intellectual property rights are inadequate, our competitive position could be harmed.

• Our success depends on our ability to retain key executives and to attract, retain and motivate qualified personnel.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains forward-looking statements which are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). These statements involve risks, uncertainties, and other factors that may cause actual results, levels of activity, performance, or achievements to be materially different from the information expressed or implied by these forward-looking statements. All statements, other than statements of historical facts, contained in this Annual Report on Form 10-K, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans and objectives of management and expected market growth are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “goal,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions, or the negative of these terms, are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

These forward-looking statements include, among other things, statements about:

• our current expectations and anticipated results of operations;

• our ability and need to raise additional funding and our ability to continue as a going concern;

• the timing and the success of preclinical studies and clinical trials of vidutolimod and any future product candidates, including our current Phase 2 trial for anti-PD-1 refractory melanoma, our current randomized Phase 2/3 trial for first-line melanoma, and our current Phase 2 proof of concept trial in advanced head and neck squamous cell carcinoma (“HNSCC”) and our currently anticipated Phase 2 proof of concept, multi-indication trial in refractory cutaneous squamous cell carcinoma (“CSCC”) and Merkel cell carcinoma (“MCC”);

• the ongoing impact of the COVID-19 pandemic on our business and the timing and enrollment of our clinical trials;

• our ability to enroll and conduct successful clinical trials or the timing or likelihood of obtaining regulatory approval for vidutolimod or any future product candidates that we may identify or develop;

4

• our ability to ensure adequate supply of vidutolimod and any future candidates;

• our ability to maintain third-party relationships necessary to conduct our business;

• our dependence upon the success of our research to generate and advance additional product candidates;

• our ability to establish an adequate safety and efficacy profile for vidutolimod or any future product candidates that we may pursue;

• the implementation of our strategic plans for our business, vidutolimod and any other product candidates we may develop and our technology;

• our intellectual property position, including the scope of protection we are able to establish and maintain for intellectual property rights covering our product candidates and technology;

• the rate and degree of market acceptance and clinical utility for vidutolimod and any other product candidates we may develop;

• our estimates about the size of our market opportunity;

• our ability to maintain and establish collaborations and strategic relationships, including our clinical trial collaborations with Bristol-Myers Squibb Company (“BMS”) and Regeneron Pharmaceuticals, Inc. (“Regeneron”);

• the potential benefits of the continued research, development, testing and manufacturing services provided by contract manufacturing organizations;

• our financial performance and liquidity;

• our ability to effectively manage our anticipated growth;

• developments relating to our competitors and our industry, including the impact of government regulation;

• our ability to retain the continued service of our key professionals and to identify, hire and retain additional qualified professionals;

• our ability to maintain adequate internal controls over financial reporting;

• our expectations regarding the period during which we qualify as an “emerging growth company” under the Jumpstart Our Business Startups Act (the “JOBS Act”);

• our expectations regarding the period during which we qualify as a “smaller reporting company”;

• our use of proceeds from our initial public offering (“IPO”) and any other fundraising and our expectations regarding our estimated expenses, the sufficiency of our cash resources, our expected cash runway and our need for additional financing; and

• other risks and uncertainties, including those listed under the section titled “Risk Factors.”

The forward-looking statements in this Annual Report on Form 10-K represent our views as of the date of this Annual Report on Form 10-K. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should therefore not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this Annual Report on Form 10-K.

We disclaim any obligation to update any forward-looking statements as a result of new information, future events or otherwise, including the potential impact of any mergers, acquisitions, divestitures or other events that may be announced after the date hereof. We may from time to time provide estimates, projections and other

5

information concerning our industry, our business and the markets for our product candidates. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties, and actual events or circumstances may differ materially from events and circumstances that are assumed in this information. Unless otherwise expressly stated, we obtained this industry, business, market, and other data from our own internal estimates and research as well as from reports, research surveys, studies, and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources. These estimates involve numerous assumptions, are subject to risks and uncertainties and are subject to change based on various factors, including those discussed under the section titled “Risk Factors” and elsewhere in this Annual Report on Form 10-K.

6

PART 1

All brand names or trademarks appearing in this report are the property of their respective owners. Unless the context requires otherwise, references in this report to “Checkmate,” the “Company,” “we,” “us” and “our” refer to Checkmate Pharmaceuticals, Inc. and its subsidiary.

Item 1. Business.

Overview

We are a clinical-stage biotechnology company focused on developing and commercializing our proprietary technology to harness the power of the immune system to combat cancer. Our product candidate, vidutolimod, is an advanced generation Toll-like receptor 9 (“TLR9”) agonist delivered as a non-infectious biologic virus-like particle (“VLP”) utilizing a CpG-A oligonucleotide as a key component. When injected into a tumor, vidutolimod is designed to trigger the body’s innate immune system, thereby altering the tumor microenvironment and directing activated anti-tumor T cells to attack both the injected tumor and also tumors throughout the body. In a clinical trial of vidutolimod in combination with a systemic checkpoint inhibitor (“CPI”) in patients with melanoma whose tumors were unresponsive or no longer responsive to a CPI, we observed a best objective response rate (“ORR”) of 28% (27/98), including post-progression responders. Most notably, we also observed a monotherapy response of 22.5% (9/40), including post-progression responders, in a similar setting. We have assembled a strong management team and infrastructure to evaluate vidutolimod across multiple tumor types in combination with other immunotherapy agents. Our founder, Art Krieg, first reported the discovery of immunostimulatory cytosine-phosphate-guanine(“CpG”) DNA in 1995, which, combined with the discovery of TLR9, led to the recognition that synthetic CpG-A oligonucleotides have the ability to stimulate the TLR9 receptor for therapeutic purposes. Our goal is to establish vidutolimod as a foundational immuno-oncology therapy that engages the innate immune system to fight cancer and improve outcomes for patients with a broad range of solid tumors.

Many tumors possess mechanisms to evade the immune system. One such evasion mechanism is through the expression of signaling molecules known as immune checkpoint proteins, which inhibit some immune cells that are capable of mounting an immune response against the tumor. Checkpoint inhibitors, such as antibodies that block programmed death receptor 1 (“ PD-1”) have the ability to reverse this mechanism of evasion, thereby unleashing anti-tumor T cells to destroy tumors. However, except with respect to certain rare tumor types, these therapies are only effective in a minority of patients, as many patients do not have an activated T cell response targeting their tumors. We have observed increased anti-tumor T cell activity in preclinical and clinical studies of the combination of a CPI with an innate immune activator of Type I interferons (“IFN-α”) a large subgroup of interferon proteins that help regulate the immune system. Of the many different IFN-α inducers that have been tested in human immune cells, TLR9 agonist CpG-A oligonucleotides have been found to be the most potent in inducing IFN-α. We believe that the distinct mechanism of action of vidutolimod, along with its structure as a VLP, leads to the activation of innate immunity in a way that initiates or restores a systemic adaptive immune response with anti-tumor T cells.

Our top priorities are to (1) advance the clinical development of vidutolimod toward marketing authorizations for the treatment of melanoma, and (2) develop vidutolimod for use across other relevant tumor types and indications. We are conducting a Phase 2 trial of vidutolimod in combination with nivolumab, or OPDIVO, in anti-PD-1 refractory melanoma. We believe that data from this trial, if successful, could help support submission of a Biologics License Application (“BLA”). We are also conducting a randomized Phase 2/3 trial of vidutolimod in combination with nivolumab in first-line melanoma. In addition to these studies in melanoma, we are evaluating new indications. including conducting a Phase 2 proof of concept trial of vidutolimod in combination with pembrolizumab, or KEYTRUDA, in recurrent/metastatic head and neck squamous cell carcinoma (“HNSCC”), and a separate, multi-indication study evaluating vidutolimod in combination with cemiplimab in non-melanoma skin cancers cutaneous squamous cell carcinoma (“CSCC”) and Merkel cell carcinoma (“MCC”).

7

Our completed Phase 1b trial evaluated vidutolimod in subjects with advanced anti-PD-1 refractory melanoma in combination with pembrolizumab and as a monotherapy. At the 2021 annual meeting of the Society for the Immunotherapy of Cancer (“SITC”), we reported a best ORR of 28% (27/98), including post-progression responders, when vidutolimod was combined with pembrolizumab. Treatment related adverse events were generally manageable, the most common consisting of flu-like symptoms and injection site reactions.

We also supported an investigator-sponsored Phase 2 trial with vidutolimod in combination with nivolumab in the pre-surgery, or neoadjuvant, setting in patients with resectable Stage III melanoma not previously treated with PD-1 blockade. Updated results from this study were posted to clinicaltrials.gov (NCT03618641) on September 16, 2021 with a Pathological Response (pCR, pMR, and pPR) of 67%, a pathological Complete Response (“pCR”) rate of 47%, and a Major Pathological Response (“MPR”) (pCR and pMR), rate of 57%. We believe these pathologic response rates in the neoadjuvant setting support the development of vidutolimod in other anti-PD-1 naïve melanoma indications, such as first-line melanoma, which we are pursuing in a clinical trial. Historical data from clinical trials of other TLR9 agonists in combination with anti-PD-1 antibodies in anti-PD-1 naïve metastatic or unresectable melanoma have shown objective response rates ranging from 49 to 76% as compared to an average of only 34 to 40% with anti-PD-1 therapy alone. We expect that we will be required to conduct a randomized trial comparing vidutolimod in combination with standard of care immunotherapy that includes PD-1 blockade versus the same standard of care immunotherapy alone if we pursue marketing authorization in the future in neoadjuvant melanoma. The FDA has granted vidutolimod a TLR9 agonist Orphan Drug Designation for the treatment of Stages IIb-IV melanoma and Fast Track designation for unresectable Stage III or Stage IV melanoma and unresectable or metastatic melanoma refractory to prior anti-PD-1 blockade.

To date, vidutolimod has been studied in more than 250 melanoma patients in clinical trials. Based on the clinical data we have generated to date, including the generally manageable adverse events we have observed, we believe there is an opportunity for vidutolimod to be developed as a differentiated immuno-oncology therapy. On the strength of the clinical results observed in multiple settings of melanoma, we are conducting additional trials with vidutolimod in combination with anti-PD-1 antibodies. The following table sets forth the current status of our existing clinical trials evaluating vidutolimod in melanoma as well as our expansion into new indications including HNSCC and non-melanoma skin cancers.

Clinical Pipeline

8

We believe the novel mechanism of action of vidutolimod creates significant potential to synergize with CPIs in two unique ways: (1) through the Type A class of CpG molecule, and (2) through the immunostimulatory effects of the VLP. To our knowledge, vidutolimod is the only investigational CpG-A class TLR9 agonist in clinical trials, and we believe the CpG-A class differs from other CpG classes in clinical development in their ability induce high levels of IFN-α. CpG-A oligonucleotides contain a native phosphodiester DNA backbone that is cleaved during TLR9 activation in order to generate the strongest possible IFN-α production. In contrast, the CpG-B and CpG-C oligonucleotides, used in other TLR9 clinical studies, consist of TLR9 agonists constructed with a phosphorothioate backbone that cannot be cleaved during plasmacytoid dendritic cells (pDC) activation, and therefore induce a lower level of IFN-α production. We believe the differences in molecular structure have a meaningful impact on molecular signaling, and potentially on clinical efficacy. CpG-A activates TLR9 in early endosomes, which is in turn associated with high IFN-α production.

Our VLP technology is designed to encapsulate and protect the CpG-A oligonucleotide from degradation in the tumor. The first injection of the VLP stimulates the production of antibodies to the VLP. On subsequent injections, the antibodies may then bind to the VLP, potentially promoting the uptake of the CpG-A cargo into the pDCs via an activating receptor on the pDCs, FcgRIIA, which has been shown in pre-clinical models to enhance the systemic anti-cancer immune effect. In contrast, CpG-B and CpG-C oligonucleotides are taken up via oligonucleotide receptors without this added immune effect from the FcgRIIA. We believe this is another important differentiating factor in the efficacy of our approach.

We believe our VLP technology confers unique properties that enhance therapeutic immune stimulation. We plan to explore the applicability of our VLP technology as we pursue other innate immune targets beyond TLR9. In addition to our internal drug discovery and development efforts, we may explore potential strategic collaborative relationships, partnerships, acquisitions and licensing opportunities to enhance the development of our current programs and potentially access additional novel product candidates in the future.

To support our business efforts, we have assembled a management team with extensive experience in pharmaceutical and biologic discovery, development and commercialization at leading biopharmaceutical and biotechnology companies including Biogen, Bristol Myers Squibb, Coley, Human Genome Sciences, Eli Lilly, Novartis, Pfizer, Takeda, Moderna and Amgen.

Vidutolimod

Vidutolimod consists of two components: (1) a capsid protein that is produced by fermentation and derived from a QBeta RNA bacteriophage and (2) a CpG-A DNA oligonucleotide that is manufactured by solid phase synthesis. These two components are combined together under controlled conditions where they self-assemble to form the VLP.

To date, vidutolimod is the only CpG-A oligodeoxynucleotide in clinical development and is differentiated in several important ways from other clinical stage TLR9 agonists, which are CpG-C oligodeoxynucleotides. We believe these differences have resulted in encouraging and differentiated clinical data.

First, CpG-A oligodeoxynucleotides are structurally distinct from CpG-C oligodeoxynucleotides, and are designed to induce a higher level of IFN-α. In contrast, CpG-C induce less IFN-α and more inflammatory cytokines and IL-10. Second, the CpG-A in vidutolimod is packaged in an immunogenic virus-like particle (VLP). A facilitating antibody response develops to the VLP, which is taken up by the target cells (plasmacytoid dendritic cells, or pDCs) through a specific receptor, FcgRIIA (CD32), that provides an additional positive signal to the pDC. In animal models, delivery via the VLP has enhanced the regression of non-injected, distant tumors.

We believe that the clinical data we have generated with vidutolimod, both in monotherapy and in combination with PD-1 blockade, demonstrate compelling proof-of-concept consistent with the distinct molecular structure. In our Phase 1b study, vidutolimod treatment in patients with anti-PD-1 refractory melanoma resulted in an ORR of

9

20% (8/40) by RECIST v1.1, and 22.5% (9/40) when including post-progression responders. In combination with pembrolizumab in patients with PD-1 refractory melanoma, the ORR was 23% (23/98) by RECIST v1.1, and 28% (27/98) when including post-progression responses. The median duration of response for monotherapy was 5.6 months and 25.2 months for the combination of vidutolimod and pembrolizumab. Furthermore, we believe that vidutolimod is the only TLR9 agonist to date to demonstrate compelling evidence of single-agent activity, despite the modest duration of response. Finally, we believe vidutolimod is the only TLR9 agonist to date to demonstrate compelling activity in combination with PD-1 blockade as neoadjuvant treatment in patients with high-risk, Stage III neoadjuvant melanoma.

Based upon the totality of the data generated to date, we are developing vidutolimod in combination with PD-1 blockade in melanoma and other tumor types. We believe our combination strategy based on anti-PD-1 antibodies, with or without other CPIs, is scientifically sound based on published studies suggesting that TLR9 agonists upregulate PD-1 on the surface of T cells and our data demonstrating a longer duration of response for vidutolimod in combination with pembrolizumab relative to vidutolimod monotherapy.

Mechanism of Action of vidutolimod

The human immune system possesses an innate ability to recognize and attack a wide variety of pathogens, including bacteria, viruses, fungi and parasites, as well as an ability to continuously surveil for dead, dying and diseased tissue. Like humans, bacteria and some viruses have DNA that encode their genome. Unlike humans, however, the DNA of viruses and bacteria has a distinct molecular structure with unmethylated CpG DNA which activates dedicated TLR9 receptors in pDCs. CpG DNA are relatively common in bacterial and viral DNA but are suppressed and methylated in human and other vertebrate DNA.

Once in an activated state, pDCs secrete large quantities of IFN-α to put the innate and adaptive immune system in a position to fight off infections and foreign bodies, such as tumors. This activation is critical since, in their resting, unactivated state in the microenvironment of many solid tumors, pDCs play an immunoinhibitory role in which they protect tumors from immune attack. We believe that vidutolimod can reverse this unfavorable pDC phenotype present in many tumors by causing these innate immune cells to trigger the body’s adaptive immune system, leading to a tumor-specific, T cell response.

Vidutolimod is structurally and biologically distinct from other TLR9 agonists in clinical development. It consists of unmethylated CpG-A DNA on a natural phosphodiester backbone and self-aggregates into G-quadruplex structures that are encapsulated in a virus-like particle to make it appear like a virus to pDCs. The graphic below illustrates the hypothetical mechanism of action of vidutolimod.

Unactivated pDCs can be recruited into tumors and protect them from immune attack. Injections of vidutolimod cause an antibody response to the VLP, which has been shown in preclinical studies to enhance the uptake of antibody-coated vidutolimod into pDCs through the activating Fc receptor, CD32. These studies also demonstrated that the VLP enhanced the systemic effect of the CpG-A beyond that of unencapsulated CpG-A. The natural phosphodiester backbone allows the CpG DNA to be cleaved inside the early endosome of the pDC, and has been shown to mediate greater activation of pDCs through TLR9. Activated pDCs can release large amounts of Type I interferons, which facilitate recruitment and activation of other immune cells, such as conventional dendritic cells, and T cells. We believe these effects can potentially culminate in the generation of large numbers of tumor-targeted T cells capable of killing the tumor both locally and systemically.

10

 

Our Development Strategy for Vidutolimod

Our clinical development strategy for vidutolimod is focused on two key pillars. First, on the strength of our clinical data to date, we intend to continue advancing clinical development toward a regulatory submission seeking approval of vidutolimod for the treatment of advanced melanoma. Second, because we believe that the mechanism of action for vidutolimod and the potential to enhance the effectiveness of PD-1 blockade are not limited to melanoma, we intend to develop vidutolimod in other relevant tumor types and indications, with an initial focus on head and neck cancer and non-melanoma skin cancers.

Clinical Data Supporting Our Vidutolimod Development Plan

We based our development plan on clinical data from three data sets:

1. Vidutolimod in combination with pembrolizumab in patients with PD-1 refractory melanoma.

2. Vidutolimod monotherapy in patients with PD-1 refractory melanoma.

3. Vidutolimod in combination with nivolumab in patients with PD-1 naïve neoadjuvant melanoma.

These data, which are described in further detail below, show that vidutolimod has been generally well-tolerated, and has demonstrated anti-tumor activity in patients as monotherapy in PD-1 refractory melanoma, and in combination with PD-1 blockade in both PD-1 refractory and PD-1 naïve, neoadjuvant melanoma. While there has not been a head-to-head clinical trial comparing the vidutolimod and anti-PD-1 therapy combination with single agent anti-PD-1 therapy, we believe that the data generated to date supports further clinical evaluation of combinations that include vidutolimod and PD-1 blockade.

Cutaneous Melanoma

Cutaneous melanoma is a particularly dangerous form of cancer because of its ability to spread to other organs rapidly if not surgically removed at an early stage, as well as low response rates and limited durability of response when treated with commonly used chemotherapeutics. In 2021, melanoma of the skin was estimated to be the fifth most diagnosed cancer, and to account for approximately 1% of all skin cancers in the United States. Estimates by the American Cancer Society of new diagnoses and deaths in 2022 as a result of melanoma in the

11

United States are 99,780 and 7,650 respectively. Most cases of melanoma are diagnosed at an early-stage and can often be cured with surgery alone. Patients diagnosed with early-stage melanoma typically have a five-year survival rate of 99%. More advanced melanoma can result in widespread metastasis to organs, including the skin, lung, brain, liver or intestines, and is less responsive to systemic therapy. Until the introduction of CPIs, treatment for metastatic melanoma primarily included surgery, radiation therapy, chemotherapy, interferon, or a combination of these treatments. According to data from the Surveillance, Epidemiology, and End Results (“SEER”) program, the five-year survival rate for metastatic melanoma patients is only about 25%. Despite the significant rates of responses achieved with CPIs compared to historical standards of care in patients with metastatic melanoma, a large portion of patients still do not respond to immunotherapy and only about half of all melanomas have genetic mutations that make them suitable for treatment with targeted therapies. Therefore, additional novel therapies are needed to expand the potential of immunotherapy to more patients.

Based on key opinion leader discussions, we believe a substantial proportion of patients with melanoma have at least one lesion that is accessible for intratumoral injection. These include cutaneous and sub-cutaneous lesions as well as palpable lymph nodes. To the extent that injection of a single lesion has been shown to have a systemic (abscopal) effect, patients with a single accessible lesion may be candidates for treatment with drugs administered by intratumoral injection. In melanoma clinical trials with vidutolimod, injections have often been performed in outpatient clinics, by physicians, nurse practitioners, and physician assistants—often without the need for any imaging to assist in the procedure. These injections have been generally described to be similar to subcutaneous injections with various agents.

Phase 1b Study of Intratumoral Vidutolimod in Patients with anti-PD-1 Refractory Melanoma

In October 2015, we initiated a two-part Phase 1b clinical trial to assess the effects of intratumoral vidutolimod in adult patients with advanced melanoma. In this trial, vidutolimod was administered intratumorally in combination with intravenous pembrolizumab in Part 1 and as monotherapy in Part 2. Vidutolimod was assessed across five dose levels, two dose schedules, and formulations (with different polysorbate 20 (“PS20”)) which were subsequently found to be above (PS20A) and below (PS20B) the critical micelle concentration. Treatment with vidutolimod as monotherapy and in combination with pembrolizumab was generally well-tolerated. Furthermore, vidutolimod reversed or overcame resistance to anti-PD-1 therapy in some patients with melanoma that progressed on prior anti-PD-1 therapy. We believe these data provide the foundation to pursue further Phase 2 studies with vidutolimod in combination with an anti-PD-1 antibody in patients who have metastatic or unresectable melanoma, particularly those with disease progression despite prior treatment with PD-1 blockade.

Adult patients with metastatic or unresectable melanoma who did not respond or had disease progression after at least four doses of treatment that included PD-1 blockade were eligible for enrollment in the trial. The objectives in Part 1 of the study were to determine the recommended dose and schedule of vidutolimod when given in combination with pembrolizumab, and to assess and describe the safety profile, pharmacodynamics, and anti-tumor activity of the combination. The objectives of Part 2 were to evaluate the safety and anti-tumor activity of vidutolimod monotherapy. Clinical benefit was assessed through measurements of objective tumor response and duration of response every 12 weeks by the site investigators according to Response Evaluation Criteria in Solid Tumors (“RECIST”) v1.1. Patients with progressive disease were allowed to continue study treatment at the discretion of the investigator. Patients with progressive disease on vidutolimod monotherapy had the option to receive vidutolimod in combination with pembrolizumab.

Between April 14, 2016, and February 27, 2020, we enrolled 159 patients to treatment were treated with vidutolimod + pembrolizumab in Part 1 and 40 patients to treatment with vidutolimod monotherapy in Part 2. A final clinical data cutoff was completed on August 17, 2021, and we presented a final analysis of the study for Parts 1 and 2 at the Society for Immunotherapy of Cancer (SITC) 2021 Virtual Meeting held from November 10-14, 2021. The safety of vidutolimod administered either in combination with pembrolizumab or as monotherapy will continue to be evaluated in a Treatment Extension, which was available to patients who were receiving treatment in Part 1 or Part 2. These patients were allowed to continue their current treatment regimen at

12

the discretion of the treating investigator with reduced study assessments focused on the collection of safety data. At the time of the data cut-off, 8 (5.0%) patients in Part 1 and 4 (10%) patients in Part 2 remained on study treatment.

Part 1—Combination Treatment with Vidutolimod and Pembrolizumab

As of August 17, 2021, 159 patients had been enrolled in Part 1 of this study Vidutoimod was given intratumorally in combination with pembrolizumab, which was administered intravenously every three weeks according to the KEYTRUDA US Prescribing Information. The median age of the patients was 64 years and 56% were male. The median number of prior therapies was two (with a range of one to eight), and all patients received one or more prior regimens containing PD-1 blockade. Seventy-five percent (119/159) of patients received monotherapy PD-1 blockade and 50% (80/159) received PD-1 blockade in combination with other agents. Forty-seven percent of the patients had prior ipilimumab as a single agent and/or in combination with other drugs. The best response to prior therapy that included PD-1 blockade was progressive disease (“PD”) in 43% of the patients, stable disease (“SD”) in 31% of the patients, partial response (“PR”) in 13% of patients, complete response (“CR”) in 4% of patients, and unknown in 8%. Prior to enrollment, the last response assessment on prior PD-1 blocking antibody therapy was PD in 93% of patients, SD in 3% and unknown in 4%. Sixty-five percent of patients had an Eastern Cooperative Oncology Group (“ECOG”) performance status of zero and 35% had an ECOG performance status of one. Thirty-six percent had melanoma with a BRAF mutation. The lactate dehydrogenase (“LDH”), an adverse prognostic factor in patients with melanoma, was elevated in 42% of patients at baseline. We previously reported that the baseline disease locations in patients enrolled to the study included skin only in 8% of patients, lymph nodes (with or without skin lesions) in 19%, soft tissue (with or without skin lesions or lymph node metastases) in 13%, bone (with or without skin, lymph nodes, or soft tissue but without visceral metastases) in 4%, and any visceral metastases in 55%.

Anti-tumor Activity

Of the 159 patients enrolled in Part 1, 98 patients initiated treatment using intratumoral vidutolimod with PS20A (PS20 concentrations of 0.005 – 0.01%) and 61 patients with PS20B (0.00167%). In the 98 patients who initiated treatment with intratumoral vidutolimod PS20A in combination with pembrolizumab, we reported at the SITC 2021 meeting a best ORR by RECIST v1.1 of 23% (23/98), and the median duration of response was 25.2 months. The ORR when including patients with a partial or complete response to continued treatment after initial disease progression was 28% (27/98). The best ORR by RECIST v1.1 in the 61 patients who initiated treatment with intratumoral vidutolimod PS20B was 11% (7/61), and the median duration of response was 11.4 months. Based on these data demonstrating a numerically higher ORR and longer duration of response, and based on additional preclinical studies supporting improved biodistribution and pharmacologic activity with the polysorbate 20 concentration above the critical micelle concentration, the PS20A formulation was selected for subsequent development. A publication in 2020 from the KEYNOTE-002 study reported that six patients out of 78 (7.7%) achieved an objective response with continued pembrolizumab treatment after initial disease progression. Based on this report, we believe that a response rate above 8% would be indicative of a treatment effect beyond that of anti-PD-1 monotherapy treatment continued after disease progression.

Based on the data from this study, we believe we have demonstrated proof of concept for vidutolimod in combination with pembrolizumab in the PD-1 refractory melanoma patient setting based on the results from this trial.

We believe that the response rate and durability of response observed with vidutolimod treatment in combination with pembrolizumab in these patients provides strong evidence that vidutolimod administered intratumorally in combination with PD-1 blockade has the potential to address the unmet medical need for patients with melanoma that is progressing despite administering a PD-1 blockade. The activity of vidutolimod in combination with pembrolizumab was observed in both injected and non-injected target lesions, as shown in the figure below. The magnitude of regression between the injected and non-injected lesions was similar. In these responding patients, the mean regression across all injected target lesions was 72% and the mean regression across all non-injected target lesions was 63%.

13

Vidutolimod + Pembrolizumab in Anti-PD-1 Refractory Melanoma: Regression in Injected and Noninjected Lesions

Safety Results

As of the data cut-off date of August 17, 2021, all but three of the 159 patients enrolled in Part 1 of the Phase 1b clinical trial had experienced at least one adverse event assessed as treatment-related to combination of pembrolizumab and vidutolimod by the investigator. As reported at the SITC 2021 meeting, the most common adverse events included flu-like symptoms and injection site reactions and typically were Grade 1 or 2. Treatment-related adverse events reported in at least 20% of patients included: chills (119 patients, 75%); pyrexia (98 patients, 62%); fatigue (85 patients, 53%); nausea (77 patients, 48%); vomiting (50 patients, 31%); injection site pain (49 patients, 31%); headache (48 patients, 30%); back pain (34 patients, 21%); and hypotension (33 patients, 21%). Based on the highest adverse event grade observed, 55 patients (35%) experienced one or more treatment-related adverse events of Grade 3, and 4 patients (3%) experienced at least one treatment-related adverse event of Grade 4. No Grade 5 treatment-related adverse events were observed. The most common Grade 3 or 4 treatment-related adverse events reported in at least three patients included hypotension (n=11, 7%), hypertension (n=8, 5%), chills, back pain (n=5 each, 3%), increased AST, hypoxia, pyrexia (n=4 each, 3%), anemia, increased ALT, arthralgia, and hypophosphatemia (n=3 each, 2%).

Twenty-six patients (16%) experienced one or more treatment-related serious adverse events (“SAEs”), which included hypotension (n=7, 4.4%); pyrexia, cytokine release syndrome, muscular weakness (each n=2, 1.3%); adrenal insufficiency, arthritis, aspartate aminotransferase increase, atrial fibrillation, basal ganglia infarction, bronchitis, cardiac congestive failure, chills, confusional state, deep vein thrombosis, diarrhea, disseminated intravascular coagulation, encephalopathy, eye inflammation, fatigue, generalized edema, hemorrhage intracranial, nausea, edema peripheral, peripheral ischemia, pneumonitis, tumor pain, and vomiting (each n=1 patient, 0.6%).Sixteen patients (10%) discontinued either vidutolimod and/or pembrolizumab treatment(s) due to an adverse event. Adverse events leading to treatment discontinuation which were considered related to treatment included pneumonitis (n=2), and duodenitis, dyspnea, injection site abscess, injection site pain, pancreatitis, injection related reaction, disseminated intravascular coagulation, colitis, diarrhoea, generalized edema, atrial fibrillation, and muscular weakness (n=1 each).

14

Part 2—Monotherapy Treatment with vidutolimod

As of the data cut-off date of August 17, 2021, 40 patients were treated with intratumoral vidutolimod monotherapy at initial doses of 5 mg or 10 mg. The median age of the patients was 68 years and 65% were male. The median number of prior lines of treatment was two (with a range of one to seven). Lactate dehydrogenase was elevated in 45% of the patients and 30% had a BRAF mutation. The ECOG PS was 0 in 50% and 1 in 50% of the patients. The last response on therapy containing a PD-1 blocking antibody was progressive disease in 80% (32 patients), stable disease in 10% (4 patients), partial response in 5% (2 patients), and unknown in 5% (2 patients). The best response on therapy containing a PD-1 blocking antibody was progressive disease in 23% (9 patients), stable disease in 45% (18 patients), partial response in 10% (4 patients), complete response in 7.5% (3 patients), and unknown in 15% (6 patients). Forty-three percent of the patients (17 patients) received prior treatment with ipilimumab as a single agent and/or in combination with other agents.

Anti-tumor Activity

At the SITC 2021 meeting, we reported a best ORR by RECIST v1.1 of 20% (8/40), and the median duration of response was 5.6 months. The ORR when including patients with a partial or complete response to continued treatment after initial disease progression was 22.5% (9/40). While we believe the monotherapy activity of vidutolimod observed in patients is compelling, the substantially longer duration of response with vidutolimod in combination with PD-1 blockade provides strong rationale for our plan to focus subsequent development of vidutolimod in combinations that include PD-1 blockade.

Safety Results

As of August 17, 2021, 38 (95%) of the 40 patients had at least one treatment-related adverse event. The most common adverse events (reported in at least 20% of patients) deemed to be treatment-related to single-agent vidutolimod included chills (24 patients, 60%); pyrexia (20 patients, 45%); nausea (19 patients, 48%); fatigue (15 patients, 38%), headache (13 patients, 32.5%), hypotension and pruritis (11 patients, 27.5%); back pain, (10 patients, 25%); and vomiting (9 patients, 23%). Nine patients (23%) experienced one or more treatment-related Grade 3 adverse events, which included hypotension (2 patients, 5%), and increased ALT, increased AST, bone pain, bradycardia, breast ulceration, flank pain, headache, hypertension, injection-related reaction, pyrexia, rash, spinal pain, and syncope (each in 1 patient, 2.5%). There were no Grade 4 or 5 treatment-related adverse events reported at the time of data cut-off. Six patients (15%) experienced one or more treatment-related SAEs. SAEs considered related to study treatments included hypotension (3 patients, 7.5%) and bradycardia, chills, cytokine release syndrome, dizziness, headache, nausea, pemphigoid, presyncope, rash, and syncope (each in 1 patient, 2.5%). Three patients discontinued study treatment due to adverse events considered related to study treatment including one subject who had bradycardia, hypotension, and presyncope, one subject who had an injection site rash, and one subject who had headache, nausea, and two chills.

Investigator-sponsored Clinical Trial of Vidutolimod in Combination with Nivolumab in PD-1 Naïve Neoadjuvant Melanoma Patient Setting

We supported an investigator-sponsored clinical trial in PD-1 naïve neoadjuvant melanoma. In August 2018, investigators at the University of Pittsburgh Medical Center began a trial to evaluate vidutolimod in combination with nivolumab as neoadjuvant therapy in patients with resectable melanoma not previously treated with PD-1 blockade. Data from this trial, as described below, have shown that vidutolimod in combination with nivolumab resulted in a high pathologic response rate, including pCR and MPR rates, was generally well-tolerated and no delays or complications related to study drug therapy were reported. We believe the high pathologic response rate observed in this investigator-sponsored trial, combined with the generally manageable adverse events we have observed in our clinical trials of vidutolimod, provide supporting evidence for the potential of vidutolimod in combination with PD-1 blockade in patients with melanoma naïve to PD-1 blockade in both the neoadjuvant and first-line metastatic/unresectable settings.

15

Trial Design and Endpoints

Eligible patients had resectable Stage IIIB, IIIC, or IIID melanoma and had not received prior treatment that included PD-1 blockade. The trial design consisted of weekly doses of vidutolimod for seven consecutive weeks in combination with three doses of nivolumab at two-week intervals. Patients then underwent surgical resection and recovery between weeks eight and 10, after which they were to receive adjuvant nivolumab in combination with vidutolimod administered subcutaneously into the area of the tumor-draining of lymph nodes for up to 54 weeks.

The primary endpoint of this trial was to evaluate MPR in patients with stage IIIB/C melanoma following 7 weeks of nivolumab and injected vidutolimod. The secondary objectives were to evaluate safety, relapse-free survival (RFS), and overall survival (OS) after 52 weeks of nivolumab/ vidutolimod combination. Data were presented on November 11, 2020 at the 35th Annual Meeting of The Society for Immunotherapy of Cancer and posted to ClinicalTrials.gov (NCT03618641) on September 16, 2021. As of the posting date of September 16, 2021, 34 patients were enrolled in the trial, and 30 completed neoadjuvant treatment and surgery and were evaluable for the primary endpoint. Patients had a median age of 64.5 years (with a range from ages 53-71). Sixteen male and 14 female patients were included in the efficacy analysis for pathological response.

Anti-Tumor Activity

The Pathologic Response rate in the 30 evaluable patients was 67%, including pCR of 47% (14/30), pMR of 10% (3/30), and pPR of 10% (3/30). The MPR (pCR and pMR) rate was 57%, and 10 patients (33%) did not have a pathological response (pNR). These data were independently reviewed. In data reported at the 2020 SITC annual meeting, the landmark 1-year RFS was 90% in patients with a pathological response.

Biopsies from patients with a pathological response to vidutolimod in combination with nivolumab showed increased density of intratumoral cluster of differentiation 8 (“CD8+”) and T cells and immunophenotyping studies revealed an increased fraction of circulating CD8+Ki67+ T cells in the blood, suggesting that treatment with vidutolimod and nivolumab was able to activate CD8+ T cells and facilitate T cell infiltration of the tumor microenvironment. Additional studies demonstrated a rim of CD303+ pDCs surrounding non-viable tumor in biopsies from some patients. We believe this is important, as tumors that exclude T cells are less likely to respond to immunotherapy with PD-1 blockade, and the potential involvement of pDCs supports our proposed mechanism of action for vidutolimod.

Safety Results

In data reported at the 2020 SITC annual meeting, treatment with vidutolimod and nivolumab was observed to be generally well-tolerated, no dose limiting toxicities were observed, and most treatment related adverse events were Grade 1 or 2, including flu-like symptoms and injection site reactions. No Grade 4 or 5 treatment related adverse events were observed. One patient with a Grade 4 skin infection (not related to vidutolimod and nivolumab) had a delay in surgery although disease remained resectable. There were no delays in planned surgery due to treatment related adverse events.

As of September 16, 2021, the most common adverse events of all grades reported in at least 20% of patients were investigations—other (28 patients, 82%); chills (22 patients, 65%); hyponatremia (22 patients, 65%); fever (19 patients, 56%); fatigue (18 patients, 53%); anemia (13 patients, 38%); nausea (12 patients, 35%); hypertension (12 patients, 35%); diarrhea (10 patients, 29%); hypophosphatemia (10 patients, 29%); musculoskeletal and connective tissue disorder (10 patients, 29%); general disorders and administration site conditions—other (9 patients, 26%); injection site reaction (9 patients, 26%); hypoalbuminemia (9 patients, 26%); skin and subcutaneous tissue disorders— other (9 patients, 26%); neutrophil count decreased (8 patients, 24%); platelet count decreased (8 patients, 24%); headache (8 patients, 24%); vomiting (7 patients, 21%); pain (7 patients, 21%); hypermagnesemia (7 patients, 21%); hyperuricemia (7 patients, 21%); hypokalemia (7 patients, 21%); arthralgia (7 patients, 21%); hematuria (7 patients, 21%); and proteinuria (7 patients, 21%). Six patients (18%) had a serious adverse event, including restrictive cardiomyopathy; general disorders and administration site conditions—other; immune system disorders—other; soft tissue infection; dyspnea; thromboembolic event (1 patient each, 3%).

16

Third-Party Neoadjuvant Clinical Trial Data

In a randomized, non-comparative trial of neoadjuvant therapy conducted at MD Anderson Cancer Center, four doses of nivolumab administered at two-week intervals (12 patients) prior to surgery yielded a pCR rate of 25% and ORR of 25% (RECIST v.1.1). In the same study, nivolumab plus ipilimumab administered at three week intervals prior to surgery (11 patients) resulted in a pCR rate of 45% and ORR of 73%. This trial was stopped early due to the inferior outcomes with nivolumab monotherapy and the high rate of Grade 3 or higher adverse events (75%) with the combination. In the OpACIN-neo trial conducted by the Netherlands Cancer Institute, 86 patients were randomized and treated in one of three cohorts of nivolumab and combined with ipilimumab at varying doses and schedules. The objective response rate ranged from 35% to 63%, and the pCR rate ranged from 23% to 57% across the cohorts. The rate of Grade 3 or higher adverse events ranged from 20 to 50%, and one of the three cohorts was closed by the Data Safety Monitoring Board for toxicity. The PRADO Trial, which was an extension of the OpACIN-neo trial, reported a pCR rate of 50% and an MPR rate of 61% from 99 patients treated with two doses of neoadjuvant ipilimumab (1 mg/kg) and nivolumab (3 mg/kg) at a 3-week interval prior to surgery. Twenty-two percent of the patients experience a treatment-related Grade 3 or higher immune-related adverse event. More recently, a neoadjuvant study conducted at MD Anderson and Memorial Sloan Kettering Cancer Centers evaluated neoadjuvant nivolumab and the anti-LAG-3 antibody, relatlimab, and reported a pCR rate of 59% and a pathologic response rate of 73% in 29 evaluable patients. Twenty-six percent of patients had a Grade 3 or 4 toxicity with adjuvant treatment following surgery.

Phase 1b Trial of Subcutaneous Vidutolimod In Patients with Advanced Melanoma

Trial Design and Endpoints

In January 2017, we initiated a two-part clinical trial of vidutolimod administered subcutaneously in combination with pembrolizumab in patients with advanced melanoma to evaluate whether subcutaneous vidutolimod is a viable route of treatment in combination with PD-1 blockade. This trial was undertaken to evaluate whether subcutaneous injection near the tumor or in the tumor-draining lymph node bed is able to generate a T cell-specific anti-tumor immune response. To be eligible for this trial, patients were required to have metastatic or unresectable melanoma and have continued disease progression despite at least four doses of treatment that included PD-1 blockade. The objectives of the trial were to determine the recommended Phase 2 dose of vidutolimod when administered subcutaneously in combination with pembrolizumab, and to assess and describe the safety profile, pharmacodynamics, and anti-tumor activity of the combination. Vidutolimod was to be injected into an area corresponding to the lymphatic drainage for one or more melanoma lesions. Clinical benefit was assessed through measurements of objective tumor response and duration of response every 12 weeks by the site investigators according to RECIST v1.1. Patients with progressive disease were allowed to continue study treatment at the discretion of the investigator.

Trial Status

As of the cutoff date of June 1, 2020, in the Part 1 dose-escalation phase of the trial, 27 patients were administered vidutolimod subcutaneously at doses ranging from 5 mg to 17.5 mg. The highest planned vidutolimod dose was 20 mg. No patients were enrolled in Part 2 of the trial. Given our plan to initiate registration studies with vidutolimod in advanced melanoma, we decided to discontinue this trial.

Interim Anti-tumor Activity

As of the cutoff date, 25 patients were evaluable for efficacy assessments, and the best ORR was 8% (2 of 25 evaluable patients by RECIST v.1.1 criteria) and included best responses of one CR and one PR, both in the 10 mg dose group (n=8). There were eight (32%) patients with a RECIST v1.1 best response of stable disease, eleven (42%) patients with a RECIST v1.1 best response of progressive disease, and four (16%) patients who discontinued prior to having a post baseline tumor assessment.

17

Interim Safety Results

As of the cutoff date, in the Part 1 dose-escalation phase of the trial, 27 patients received vidutolimod SC. All but four patients had at least one adverse event assessed as treatment-related by the Investigator. Most were Grade 1 or 2 adverse events, and included flu-like symptoms and injection site reactions. Four patients (14.3%) had one or more treatment-related adverse events of Grade 3 or higher which included increased LDH, erythema multiforme, fatigue, pain and tumor pain (1 patient, 4%). One patient (4%) discontinued treatment due to an adverse event of pain due to disease progression that was unrelated to study treatment. Two patients (8%) had a treatment-related serious adverse event. One patient had Grade 3 tumor pain in the abdomen and one had Grade 3 erythema multiforme. Adverse events considered related to study treatment occurring in at least 20% of patients included fatigue (14 patients, 51.9%); chills (6 patients, 22.2%), and nausea (6 patients, 22.2%).

Clinical Development Plans

Our clinical development strategy is to pursue registration of vidutolimod in combinations tht include a PD-1 blocking antibody for the treatment of patients with advanced melanoma, and to establish proof of concept in other advanced cancers, beginning with HNSCC. To this end, we are conducting four clinical studies:

(1) a single-arm Phase 2 trial of vidutolimod and nivolumab in patients with anti-PD-1 refractory melanoma;

(2) a randomized Phase 2/3 trial of vidutolimod and nivolumab vs. nivolumab in patients with first-line melanoma;

(3) a single-arm Phase 2 proof of concept trial of vidutolimod and pembrolizumab in patients with HNSCC; and

(4) a multi-indication basket trial currently focused on single arm cohorts of non-melanoma skin cancers (CSCC and MCC) previously treated with PD-1 blockade.

In addition to our studies in melanoma, HNSCC and non-melanoma skin cancers, we intend to conduct additional clinical trials to evaluate vidutolimod in combination with PD-1 blockade in other cancers.

I. Development Plan for Vidutolimod For the Treatment of Melanoma

The first priority in our development strategy is to progress toward registration for the treatment of both first-line and PD-1 refractory melanoma. We believe that the preliminary data described above provide supportive evidence of vidutolimod’s activity in combination with PD-1 blockade, and we intend to initiate clinical trials to advance toward applications for marketing authorization for vidutolimod for the treatment of anti-PD-1 refractory melanoma and first-line melanoma.

Collaboration with BMS

On December 7, 2020, we entered into a clinical collaboration with Bristol-Myers Squibb Company (“BMS”), pursuant to which BMS agreed to provide nivolumab for our Phase 2 refractory melanoma study and Phase 2 first-line melanoma study, at its own expense.

Phase 2 Clinical Trial in Anti-PD-1 Refractory Melanoma

We are conducting Trial CMP-001-010, a multicenter, open-label, Phase 2 trial of intratumoral vidutolimod in combination with intravenous nivolumab in patients with anti-PD-1 refractory melanoma. We are conducting this trial at clinical sites in the United States. The primary outcome measure is to determine the confirmed objective response (ORR) based on RECIST v1.1 as assessed by blinded independent central review (BICR). The secondary outcome measures include safety and tolerability, duration of response (DOR), treatment response in

18

non-injected target lesions, progression-free survival (PFS), overall survival (OS), immune objective response rate (iORR), immune duration of response (iDOR), immune progression-free survival (iPFS), pharmacokinetics, and immunogenicity. The trial is currently recruiting patients and we anticipate approximately 100 patients to be enrolled.

Randomized Phase 2/3 Clinical Trial in First-line Melanoma

We are conducting Trial CMP-001-011, a multi-center, Phase 2/3 randomized, active-controlled, open-label trial of intratumoral vidutolimod in combination with intravenous nivolumab versus nivolumab alone in patients with previously untreated advanced or metastatic melanoma. The primary outcome measure for Phase 2 is to determine the confirmed ORR of vidutolimod in combination with nivolumab versus nivolumab monotherapy based on RECIST v1.1 as determined by BICR. The secondary outcome measures for Phase 2 include safety and tolerability. Approximately 140 patients are expected to be enrolled in Phase 2, and if the primary endpoint of Phase 2 is met, the trial may proceed into Phase 3 with a total trial sample size of approximately 450 patients. The primary outcome measure for Phase 3 is to evaluate the PFS of vidutolimod in combination with nivolumab versus nivolumab monotherapy based on RECIST v1.1 as determined by BICR. The secondary outcome measures for Phase 3 include safety and tolerability, OS; confirmed ORR, DOR, and disease control rate (DCR) based on RECIST v1.1 as determined by BICR; treatment response in non-injected target lesions, iPFS, iDOR, and iORR Trial enrollment is ongoing in the Phase 2 portion of the trial.

We believe that these two melanoma trials could inform and enable a registration strategy in PD-1 naïve first-line melanoma, PD-1 refractory melanoma, or both.

Regulatory Status of Melanoma Development Program

In February 2020, we received Orphan Drug Designation for a TLR9 agonist (vidutolimod) for the treatment of Stages IIb-IV melanoma.

In March 2020, we met with the FDA to discuss the potential for pursuing accelerated approval of vidutolimod based upon the single-arm trial in anti-PD-1 refractory melanoma described above, and to pursue full approval in CPI-naïve first-line melanoma based upon a randomized trial comparing vidutolimod in combination with PD-1 blockade vs. PD-1 blockade alone. With respect to our plans to seek accelerated approval in anti-PD-1 refractory melanoma, the FDA indicated that we would likely be required to provide ORR data from a randomized trial to assess the contribution of individual components to the effect of the combination. In July 2020, we received Fast Track designation for vidutolimod in combination with a PD-1 blocking antibody (nivolumab or pembrolizumab) for the initial treatment of patients with unresectable or metastatic melanoma refractory to prior anti-PD-1 blockade. We plan to generate ORR data from the randomized, controlled trial in first-line melanoma described above, but there is no guarantee that such ORR data will support a BLA seeking accelerated approval of vidutolimod in anti-PD1 refractory melanoma.

We intend to seek data exclusivity or market exclusivity for our product candidates provided under the Federal Food, Drug and Cosmetic Act (“FDCA”) and similar laws in other countries. We believe that vidutolimod could qualify for 12 years of data exclusivity, from the date of approval, under the Biologics Price Competition and Innovation Act of 2009 (“BPCIA”), which was enacted as part of the Patient Protection and Affordable Care Act. Under the BPCIA, a BLA cannot be submitted to the FDA until four years, or if approved by the FDA, until 12 years, after the original brand product identified as the reference product is approved under a BLA. The BPCIA provides an abbreviated pathway for the approval of biosimilar and interchangeable biological products.

II. Develop Vidutolimod For Use Across Other Tumor Types and Indications

We believe vidutolimod has the potential to be developed for any cancer type where PD-1 blockade has shown some degree of efficacy, but where significant unmet medical need remains. We are conducting a clinical trial in

19

HNSCC in patients who have not yet received treatment with PD-1 blockade. We are conducting a basket study of vidutolimod and cemiplimab in PD-1 refractory CSCC and MCC patient cohorts. We are also supporting a small number of investigator-sponsored studies in melanoma and other cancers.

Vidutolimod and Pembrolizumab in PD-1 Naïve HNSCC

HNSCC represents a number of different malignant tumors that develop in or around the throat, larynx, nose, sinuses and mouth, and accounts for approximately 3.6% of all cancers in the United States. Most head and neck cancers are squamous cell carcinomas. According to the American Cancer Society, there will be an estimated 54,000 new diagnoses and approximately 11,230 patients will die as a result of head and neck cancer in the United States in 2022. According to the American Cancer Society, the five-year survival rate for HNSCC is approximately 65%. Treatments for HNSCC include surgery, radiation therapy, chemotherapy, targeted therapy, immunotherapy, or a combination of treatments. HNSCC tumors are an attractive setting for immunotherapy clinical research as they have a high tumor mutation burden leading to the expression of a number of tumor-specific antigens that could lead to recognition by the adaptive immune system and killing of the tumor by tumor-specific T cells. While nivolumab was approved for treatment of patients with recurrent and metastatic HNSCC with ORR of 13.3% and pembrolizumab was approved for first-line treatment of HNSCC with ORR of 19%, based on the ORR for these agents, we believe there is a significant unmet clinical need for new treatment options.

We are conducting a Phase 2 trial of vidutolimod and pembrolizumab in patients with HNSCC that have not been previously treated with PD-1 blockade. Eligible patients for this trial are expected to have recurrent or metastatic cancers of the oropharynx, oral cavity, hypopharynx, or larynx that are incurable with available therapies. Treatment includes intratumoral injections of vidutolimod combined with intravenous pembrolizumab at its approved dose and schedule. The primary outcome measure is to determine the confirmed, investigator-assessed ORR based on RECIST v1.1. The secondary outcome measures include safety and tolerability; efficacy characterized by DOR, PFS, OS, iORR, iDOR, and iPFS; and the effect of human papillomavirus (HPV) infection and programmed death ligand 1 (PD-L1) expression on efficacy. The trial is currently recruiting patients and we plan to enroll approximately 43 patients.

Vidutolimod and cemiplimab in CSCC and MCC

CSCC is the second most common form of skin cancer behind basal cell carcinoma. As many as 700,000 people each year will develop CSCC in the United States. Sun exposure is a significant risk factor, and development of CSCC is associated with more sun exposure, sunburns, and indoor tanning. Most cases are cured with surgical resection; however, some tumors with high-risk features develop local or even distant metastatic disease. Some cases with residual disease following surgical resection may be treated with curative intent using radiation with or without systemic chemotherapy. More advanced disease may be treated with PD-1 blocking antibodies, and LIBTAYO and KEYTRUDA are approved for the treatment of locally recurrent, advanced, or metastatic CSCC. Response rates range from approximately 35–50% and response duration is approximately one year in 35–76% of treated patients depending on the clinical setting. Despite the excellent prognosis experienced by the majority of patients, the number of deaths due to CSCC annually is similar to that of cutaneous melanoma. Thus, significant unmet need remains for therapeutic advances in this setting.

MCC is a rare skin cancer that originates in neuroendocrine cells of the skin. There are approximately 2,500 new cases of MCC in the United States annually, and the incidence is rising about 5 – 10% per year. The majority of patients diagnosed with MCC are over the age of 70 and men are twice as likely to be diagnosed with MCC as women. MCC generally occurs on sun-exposed regions of skin, and many cases appear to be associated with a novel Merkel Cell polyoma virus. MCC can grow rapidly, with approximately one-third of cases having regional lymph node involvement and as many as 16% have distant metastatic spread. The 5-year survival for patients with distant metastatic disease is ~19%. Checkpoint inhibitors, including BAVENCIO (avelumab) for metastatic disease and KEYTRUDA for locally recurrent or metastatic disease, are approved by treatment of MCC by the

20

FDA. The ORR for BAVENCIO in the metastatic setting was 33% with a 1-year duration of response of 45%. The ORR for KEYTRUDA in patients with locally advanced or metastatic MCC was 56% with a 1-year response duration of 54%. Given the potential for locoregional and metastatic spread and the high mortality with distant disease, there is clear unmet need for patients with advanced MCC.

We are conducting a multi-indication, Phase 2 trial of intratumoral vidutolimod in combination with intravenous cemiplimab-rwlc, and we are currently enrolling patients with MCC or CSCC who have progressed while receiving PD-1-blocking antibody(ies) or within 3 months of discontinuation. The primary endpoint is ORR by investigator assessment, and secondary endpoints include safety and tolerability and duration of response. We anticipate approximately 23 patients to be enrolled in our refractory CSCC and MCC cohorts. While the protocol includes the possibility of a first-line CSCC cohort as well as other indications, we are not enrolling those cohorts at the current time.

Investigator-Sponsored Clinical Trials in Cancers with High Unmet Medical Need

In addition to the clinical trial in patients with PD-1 naive neoadjuvant melanoma described above, we are currently supporting four other investigator-sponsored studies, each under their own investigator IND, where vidutolimod is administered in combination with other cancer immunotherapy treatments, with or without radiation therapy, in patients with metastatic mismatch repair proficient colorectal cancer, lymphoma, triple negative breast cancer, and pancreas cancer. Of these, the trials in metastatic colorectal cancer, triple negative breast cancer, neoadjuvant Stage III melanoma, and lymphoma have initiated enrollment. No data has been presented by the Sponsors of these trials. Adverse events attributable to vidutolimod in clinical trials from other sponsors have been consistent with safety observations from Checkmate-sponsored trials.

Investigator Sponsored Studies

• NCT03507699—Combination treatment of nivolumab, ipilimumab, intratumoral CMP-001 and radiosurgery for liver metastases in colorectal carcinoma. This Phase-1 study is being conducted at Sheba Medical Center, Ramat Gan, Israel and is evaluating the safety and efficacy of vidutolimod in combination with nivolumab, ipilimumab, and radiosurgery for liver metastases in colorectal carcinoma.

• NCT03983668—Phase 1/2 study of pembrolizumab and in-situ injection of vidutolimod in patients with relapsed and refractory lymphomas. This is an ongoing study being conducted at the University of Iowa Holden Comprehensive Cancer Center evaluating the safety and efficacy of vidutolimod in combination with pembrolizumab in patients with relapsed and refractory lymphomas.

• NCT04807192—Phase 2, open-label, window of opportunity, randomized study evaluating vidutolimod in combination with pre-operative stereotactic body radiation therapy in patients with early-stage triple negative breast cancer. This study is being conducted at the Centre Hospitalier Universitaire Vaudois in Switzerland to evaluate the biological activity of preoperative stereotactic body radiotherapy alone and combined with vidutolimod SC followed by IT in subjects with early stage TNBC.

• NCT04387071—The Seena Magowitz Phase IB/II Trial of CMP-001 (a TLR9 Agonist) in Combination With INCAGN01949 (an Activating Anti-OX40 Antibody) for In Situ Intratumoral Injection for Patients With Stage IV Pancreatic and Other Cancers Except Melanoma. This study is being conducted at the University of Southern California to evaluate the safety and efficacy of vidutolimod in combination with INCAGN01949.

Clinical Trial Collaboration Study:

• NCT04708418/EA6194—A Phase II Evaluation of Neoadjuvant Pembrolizumab Alone or in Combination with CMP-001 in Patients with Operable Melanoma: Efficacy and Biomarker Study. This is a randomized study being conducted by the National Cancer Institute (NCI) to evaluate the effect of

21

pembrolizumab alone or in combination with vidutolimod in treating patients with melanoma that can be treated by surgery (operable).

Competition

The biotechnology and pharmaceutical industries, and the immuno-oncology subsector, are characterized by the rapid evolution of technologies, fierce competition and strong defense of intellectual property. While we believe that vidutolimod and our technology, knowledge, experience and scientific resources provide us with certain competitive advantages, we face competition from many sources including pharmaceutical and biotechnology companies, academic institutions, governmental agencies and public and private research institutions. Any product candidate that we successfully develop and commercialize will compete with a range of currently approved cancer therapies and any new therapies that may become available in the future. Our competitors include larger and better funded biopharmaceutical, biotechnology and therapeutics companies, specifically companies focused on cancer immunotherapies, such as Amgen, Inc., AstraZeneca plc, BMS, Genentech, Inc., GlaxoSmithKline PLC, Merck & Co., Inc., Novartis AG, Pfizer Inc., Regeneron, Roche Holding Ltd and Sanofi S.A. Paradoxically, many of these companies are developing systemic immunotherapeutics which have the potential to be developed in combination with vidutolimod and so we view them both from a competitive and complementary perspective.

Oncology drugs and therapeutics on the market range from traditional cancer therapies, including chemotherapy, to antibody-drug conjugates, such as Genentech Inc.’s KADCYLA, to immune checkpoint inhibitors targeting CTLA-4, such as BMS’ YERVOY, and PD-1/PD-L1, such as BMS’ OPDIVO, Merck & Co.’s KEYTRUDA, Regeneron’s LIBTAYO, Pfizer’s BAVENCIO and Genentech’s TECENTRIQ, to T cell-engager immunotherapies, such as Amgen’s BLINCYTO and to oncolytic immunotherapies, including Amgen’s T-Vec, an FDA-approved oncolytic immunotherapy for treating advanced melanoma. Consistent with our strategy of evaluating vidutolimod in combination with anti-PD-1 antibodies, we believe a number of the PD-1/PD-L1 therapies may be complementary to vidutolimod. BMS’ recently approved relatlimab would be expected to affect the treatment landscape for the first-line metastatic or unresectable melanoma, and could have competitive and complementary dynamics for vidutolimod and the enrollment of our clinical trials.

Additionally, we view companies that are developing innate immune activators as our most direct potential competitors. These include approaches to activate Toll-like receptors such as TriSalus Life Sciences, Idera Pharmaceuticals, Bolt Therapeutics, and Silverback; cytokine therapies such as a plasmid IL-12 from Oncosec; and companies developing oncolytic viruses, such as Replimune. In addition, Iovance Therapeutics is developing tumor-infiltrating lymphocyte therapies that may be approved for use in the same patient populations that vidutolimod is being developed to treat and/or that may have utility for similar indications that we are targeting. Moreover, we may also compete with smaller or earlier-stage companies, universities and other research institutions that have developed, are developing or may be developing current and future cancer therapeutics.

Our success will be based in part upon our ability to successfully commercialize vidutolimod and to identify, develop and manage a portfolio of therapeutics that are safer and more effective than competing products in our target indications. Our market opportunity has the potential to be reduced or eliminated if our competitors develop and commercialize products that are safer, more effective, have fewer side effects, are not administered by intratumoral injection or otherwise are more convenient for patients, as well as clinical investigators and physicans and their respective staffs,or are less expensive than any therapeutics we may develop. Our competitive position will also be dependent upon our ability to attract and retain qualified personnel, to obtain patent protection or otherwise develop proprietary products or processes, and protect our intellectual property, and to secure sufficient capital resources for the period between technological conception and commercial sales. The availability of reimbursement from government and other third-party payors will also significantly affect the pricing and competitiveness of our products. Our competitors may also obtain FDA or other regulatory approval for their products more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market.

22

Intellectual Property

We believe our rights under issued patents and if allowed, our patent applications, will provide a competitive advantage. Our success depends in part on our ability to obtain and maintain proprietary protection for our product candidates, technology and know-how, to operate without infringing the proprietary rights of others and to defend and enforce our intellectual property rights. Our policy is to seek to protect our proprietary position by, among other methods, filing United States and foreign patent applications related to our proprietary technology, inventions and improvements that are important to the development of our business. We also rely on trade secrets, know-how and continuing technological innovation to develop and maintain our proprietary position.

For the core technology related to vidutolimodand its component parts, we are prosecuting four families of patent applications which we own, including composition of matter, methods of use, combination therapies, drug delivery, dose volume, aggregation, packaging and biomarkers. Further, we have an exclusive license for seven families of patents and patent applications including composition of matter, manufacturing methods, aggregation, packaging and synthesis claims. Some of our patents have issued in the United States and internationally and others are pending in the United States and internationally (either in foreign jurisdictions or under the Patent Cooperation Treaty (“PCT”)). As of March 6, 2022, we own or exclusively license the rights to 13 issued US granted patents, 131 granted patents outside of the United States, and 29 pending patent applications worldwide. We or our licensors have filed patent applications in 33 foreign jurisdictions including the EU, Canada, Japan, China, Australia, Italy, the Netherlands, India, France and Germany. The patents include claims directed to combination therapy of TLR9 agonists and checkpoint inhibitors, volumes and methods for administration, biomarkers, aggregation and packaging and methods of treatment claims. We estimate, without taking potential patent term extensions into account, that these issued patents will expire between 2036 and 2038.

The term of individual patents depends upon the legal patent term in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the earliest date of filing a non-provisional patent application. In the United States, a patent that covers an FDA-approved drug may also be eligible for a patent term extension, which permits restoration of a portion of the patent term elapsed during the U.S. clinical development and FDA regulatory review process. The Hatch-Waxman Act permits a patent term extension of up to five years beyond the expiration of the patent. The length of the patent term extension is related to the length of time the drug is under clinical development in the United States and the length of time the drug is under regulatory review. Patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval and only one patent applicable to an approved drug may be extended. Similar provisions are available in Europe and other foreign jurisdictions to extend the term of a patent that covers an approved drug. In the future, if and when our products receive FDA approval, and if and when patents are granted, we expect to apply for patent term extensions on patents covering those products. We plan to seek patent term extensions for each of our issued patents in any jurisdiction where these are available, however there is no guarantee that the applicable authorities, including the FDA in the United States, will agree with our assessment of whether such extensions should be granted, and if granted, the length of such extensions.

We may rely, in some circumstances, on trade secrets to protect our technology. We seek to protect our proprietary technology and processes, in part, by confidentiality agreements with our employees, consultants, scientific advisors and other contractors, as well as physical security of our premises and our information technology systems.

We intend to seek data exclusivity or market exclusivity for our product candidates provided under the FDCA and similar laws in other countries. We believe that vidutolimod could qualify for 12 years of data exclusivity, from the date of approval, under the Biologics Price Competition and Innovation Act of 2009 (“BPCIA”), which was enacted as part of the Patient Protection and Affordable Care Act. Under the BPCIA, a BLA cannot be submitted to the FDA until four years, or if approved by the FDA, until 12 years, after the original brand product identified as the reference product is approved under a BLA. The BPCIA provides an abbreviated pathway for the approval of biosimilar and interchangeable biological products.

23

License Agreement with Kuros

In June 2015, we entered into an exclusive license agreement with Cytos Biotechnology LTD (now Kuros Biosciences AG (“Kuros”)) as amended in August 2017 and as further amended in January 2018 (the “Kuros License Agreement”). Pursuant to the Kuros License Agreement, we were granted an exclusive, royalty-bearing, sublicensable, worldwide license, under all of Kuros’ intellectual property rights, including any intellectual property rights arising during the term of the agreement, to commercially develop, manufacture, use, distribute, and sell certain therapeutic products, including vidutolimod, or the Licensed Products, for the diagnosis, treatment and prevention of all indications in humans and animals. Under the terms of the Kuros License Agreement, we are required to use commercially reasonable efforts to develop at least one Licensed Product.

Under the Kuros License Agreement, we have paid Kuros licensing fees totaling $8.25 million to date., including $1.0 million paid upon execution of the agreement in 2015 and $250 thousand paid upon execution of the second amendment in 2018. We also agreed to make payments to Kuros for each product that achieves certain development and regulatory milestones, including payments of up to $56 million for the current oncology programs. In 2021 the Company made milestone payments of $2 million and $4 million upon the respective dosings of first patients in Phase 2 and Phase 3 clinical trials.

We are also required to pay tiered royalties of high single-digit to low teens percentages on annual net sales of Licensed Products that are covered by a licensed patent, as well as royalties at 50% of the foregoing amounts with respect to sales of Licensed Products that are not covered by a licensed patent, but are covered by licensed know-how. The royalty obligation will terminate on a country-by-country basis on the later of (i) the expiration date of the last valid claim, including composition of matter, manufacturing methods, aggregation, packaging or synthesis claims, within the licensed patent rights, each of which will expire between 2022 and 2027 with potential patent term extensions ranging from two months to five years, (ii) the loss of regulatory exclusivity in such country, and (iii) the tenth anniversary of the first commercial sale of such product in such country.

The Kuros License Agreement will expire upon the expiration of the last-to-expire royalty term for the Licensed Products in the territory. Either party has the right to terminate the agreement in full for an uncured material breach of the agreement upon written 60 days’ notice to the other party. We have the right to terminate the agreement for any reason upon 90 days’ written notice to Kuros.

Clinical Trial Collaboration and Supply Agreements

On May 10, 2021, we entered into a Supply and Non-Exclusive License Agreement (“SNLA”) with Regeneron. The SNLA dictates the general terms that govern specific collaborative studies between Checkmate and Regeneron, including a Phase 2 proof of concept trial, with patient cohorts in anti-PD-1 naïve and anti-PD-1 refractory CSCC and anti-PD-1 refractory MCC. Pursuant to the SNLA, Regeneron agreed to provide cemiplimab, a drug to be used concurrently or in combination with vidutolimod in the aforementioned studies, at its own expense. As part of the SNLA, the parties granted each other non-exclusive licenses to use background intellectual property and regulatory documentation to seek regulatory approval of the other party’s compound solely for use as a combination therapy. We do not expect any future consideration to be payable to Regeneron pursuant to the SNLA.

On December 7, 2020, we entered into the Master Clinical Trial Collaboration Agreement (“MCTCA”) with BMS. The MCTCA dictates the general terms that govern specific collaborative studies between the companies, including our Phase 2 refractory melanoma study and Phase 2 first-line melanoma study (collectively, the “collaborative studies”). Pursuant to the MCTCA, BMS agreed to provide nivolumab, a drug to be used in combination with vidutolimod, in the collaborative studies, at its own expense. As part of the MCTCA, the parties granted each other non-exclusive licenses to use background intellectual property and regulatory documentation to seek regulatory approval of the other party’s compound solely for use as a combination therapy. We do not expect any future consideration to be payable to BMS pursuant to the MCTCA.

24

Manufacturing & Supply

We do not have any manufacturing facilities or personnel. We currently rely, and expect to continue to rely, on third parties for the manufacture of vidutolimodand any future product candidates for preclinical and clinical testing, as well as for commercial manufacture if our product candidates receive marketing approval. We source our manufacturing and supply requirements with a number of contract manufacturing organizations (“CMOs”) through the issuance of work orders on an as-needed basis. We currently do not have any long-term supply contracts. We depend and will continue to depend on our CMOs to manufacture our drug candidates in accordance with current Good Manufacturing Practices (“cGMP”) regulations for use in clinical trials.

We manage multiple CMOs to develop and manufacture vidutolimoddrug product. Vidutolimodis a VLP comprised of a Qb (“Qbeta”) coat protein that is assembled around an immunostimulatory CpG-A oligodeoxynucleotide, G10. Qb is recombinantly produced by fermentation in E. coli, and then purified free of other cellular material at one of our CMOs. The G10 oligonucleotide is produced via solid support phosphoramidite chemistry at one of two additional CMOs. The two drug substance intermediates, Qb and G10, are combined in an aqueous salt buffer where they self-assemble into virus-like particles prior to final purification of the drug substance at another CMO. Another CMO performs the fill and finish of the final drug product.

Sales and Marketing

In light of our stage of development, we have not yet established a commercial organization or distribution capabilities. We have retained worldwide commercial rights for our product candidates. If our product candidates receive marketing approval, we plan to commercialize them in the United States with our own focused, specialty sales force. We also plan to evaluate options for delivering vidutolimod, if approved, to patients in other key markets such as Europe, Japan, and China, which may include strategic collaborations.

Government Regulation

The FDA and other regulatory authorities at federal, state and local levels, as well as in foreign countries, extensively regulate, among other things, the research, development, testing, manufacture, quality control, import, export, safety, effectiveness, labeling, packaging, storage, distribution, record keeping, approval, advertising, promotion, marketing, post-approval monitoring and post-approval reporting of biologics such as those we are developing. We, along with our vendors, collaboration third-parties, CROs and contract manufacturers, will be required to navigate the various preclinical, clinical, manufacturing and commercial approval requirements of the governing regulatory agencies of the countries in which we wish to conduct studies or seek approval of our product candidate. The process of obtaining regulatory approvals of drugs and ensuring subsequent compliance with appropriate federal, state, local and foreign statutes and regulations requires the expenditure of substantial time and financial resources.

In the United States, where we are initially focusing our product development, the FDA regulates biologics under the FDCA and the Public Health Service Act (“PHSA”) and their implementing regulations. Biologics are also subject to other federal, state and local statutes and regulations. Our product candidate is early-stage and has not been approved by the FDA for marketing in the United States.

The process required by the FDA before our product candidate is approved for therapeutic indications and may be marketed in the United States generally involves the following:

• completion of extensive preclinical studies in accordance with applicable regulations, including studies conducted in accordance with Good Laboratory Practice (“GLP”) requirements;

• submission to the FDA of an IND, which must become effective before clinical trials may begin and must be updated annually or when significant changes are made;

25

• approval by an Institutional Review Board (“IRB”) or independent ethics committee at each clinical trial site before each trial may be initiated;

• performance of adequate and well-controlled clinical trials in accordance with Good Clinical Practice (“GCP”) requirements and other clinical trial-related regulations to establish the safety, efficacy, purity and potency of the proposed biological product candidate for its intended purpose;

• preparation and submission to the FDA of a BLA after completion of all pivotal trials;

• a determination by the FDA within 60 days of its receipt of a BLA, to file the application for review;

• satisfactory completion of one or more FDA pre-approval inspections of the manufacturing facility or facilities where the product will be produced to assess compliance with current Good Manufacturing Practice requirements (“cGMPs”) to assure that the facilities, methods and controls are adequate to preserve the biological product’s continued safety, purity and potency;

• potential FDA audit of the clinical trial sites that generated the data in support of the BLA;

• payment of user fees for FDA review of the BLA; and

• FDA review and approval of the BLA, including consideration of the views of any FDA advisory committee, prior to any commercial marketing or sale of the biologic in the United States.

Preclinical and clinical trials for biologics

Before testing any drug or biologic in humans, the product candidate must undergo rigorous preclinical testing. Preclinical studies include laboratory evaluations of chemistry, formulation and stability, as well as in vitro and animal studies to assess safety and in some cases to establish the rationale for therapeutic use. The conduct of preclinical studies is subject to federal and state regulations and requirements, including GLP requirements for safety and toxicology studies. The results of the preclinical studies, together with manufacturing information and analytical data must be submitted to the FDA as part of an IND. An IND is a request for authorization from the FDA to administer an investigational product to humans, and must become effective before clinical trials may begin. The central focus of an IND submission is on the general investigational plan and the protocol(s) for clinical studies. The IND also includes results of animal and in vitro studies assessing the toxicology, pharmacokinetics, pharmacology, and pharmacodynamic characteristics of the product; chemistry, manufacturing, and controls information; and any available human data or literature to support the use of the investigational product. The IND automatically becomes effective 30 days after receipt by the FDA, unless the FDA, within the 30-day time period, raises concerns or questions about the conduct of the clinical trial, including concerns that human research subjects will be exposed to unreasonable health risks, and imposes a clinical hold. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. Some long-term preclinical testing may continue after the IND is submitted. Accordingly, submission of an IND may or may not result in FDA authorization to begin a trial. A separate submission to an existing IND must also be made for each successive clinical trial conducted during product development of a product candidate, and the FDA must grant permission, either explicitly or implicitly by not objecting, before each clinical trial can begin.

The clinical stage of development involves the administration of the product candidate to healthy volunteers or patients under the supervision of qualified investigators, generally physicians not employed by or under the trial sponsor’s control, in accordance with GCP requirements, which include the requirements that all research subjects provide their informed consent for their participation in any clinical trial. Clinical trials are conducted under protocols detailing, among other things, the objectives of the clinical trial, dosing procedures, subject selection and exclusion criteria and the parameters and criteria to be used in monitoring safety and evaluating effectiveness. Each protocol, and any subsequent amendments to the protocol, must be submitted to the FDA as part of the IND. Furthermore, each clinical trial must be reviewed and approved by an IRB for each institution at which the clinical trial will be conducted to ensure that the risks to individuals participating in the clinical trials

26

are minimized and are reasonable related to the anticipated benefits. The IRB also approves the informed consent form that must be provided to each clinical trial subject or his or her legal representative, and must monitor the clinical trial until completed. The FDA, the IRB, or the sponsor may suspend or discontinue a clinical trial at any time on various grounds, including a finding that the subjects are being exposed to an unacceptable health risk. Some studies also include oversight by an independent group of qualified experts organized by the clinical trial sponsor, known as a data safety monitoring board, which provides authorization for whether or not a trial may move forward at designated check points based on access to certain data from the trial and may halt the clinical trial if it determines that there is an unacceptable safety risk for subjects or other grounds, such as no demonstration of efficacy. There also are requirements governing the reporting of ongoing clinical trials and completed clinical trials to public registries. Information about applicable clinical trials, including clinical trials results, must be submitted within specific timeframes for publication on the www.clinicaltrials.gov website.

While we may conduct international clinical trials under INDs in the future, a sponsor who wishes to conduct a clinical trial outside of the United States may, but need not, obtain FDA authorization to conduct the clinical trial under an IND. The FDA will accept a well-designed and well-conducted foreign clinical trial not conducted under an IND if the trial was conducted in accordance with GCP requirements, and the FDA is able to validate the data through an onsite inspection if deemed necessary.

Clinical trials to evaluate therapeutic indications to support BLAs for marketing approval are typically conducted in three sequential phases, which may overlap.

• Phase 1—Phase 1 clinical trials involve initial introduction of the investigational product into healthy human volunteers or patients with the target disease or condition. These studies are typically designed to test the safety, dosage tolerance, absorption, metabolism and distribution of the investigational product in humans, evaluate the side effects associated with increasing doses, and, if possible, to gain early evidence of effectiveness.

• Phase 2—Phase 2 clinical trials typically involve administration of the investigational product to a limited patient population with a specified disease or condition to evaluate the preliminary efficacy, optimal dosages and dosing schedule and to identify possible adverse side effects and safety risks. Multiple Phase 2 clinical trials may be conducted to obtain information prior to beginning larger and more expensive Phase 3 clinical trials.

• Phase 3—Phase 3 clinical trials typically involve administration of the investigational product to an expanded patient population to further evaluate dosage, to provide statistically significant evidence of clinical efficacy and to further test for safety, generally at multiple geographically dispersed clinical trial sites. These clinical trials are intended to establish the overall risk/benefit ratio of the investigational product and to provide an adequate basis for product approval. Generally, two adequate and well-controlled Phase 3 clinical trials are required by the FDA for approval of a BLA.

Post-approval trials, sometimes referred to as Phase 4 clinical trials, may be conducted after initial marketing approval. These trials are used to gain additional experience from the treatment of patients in the intended therapeutic indication and are commonly intended to generate additional safety data regarding use of the product in a clinical setting. In certain instances, the FDA may mandate the performance of Phase 4 clinical trials as a condition of approval of a BLA.

Progress reports detailing the results of the clinical trials, among other information, must be submitted at least annually to the FDA and written IND safety reports must be submitted to the FDA and the investigators fifteen days after the trial sponsor determines the information qualifies for reporting for serious and unexpected suspected adverse events, findings from other studies or animal or in vitro testing that suggest a significant risk for human participants exposed to the biologic and any clinically important increase in the rate of a serious suspected adverse reaction over that listed in the protocol or investigator brochure. The sponsor must also notify the FDA of any unexpected fatal or life-threatening suspected adverse reaction as soon as possible but in no case later than seven calendar days after the sponsor’s initial receipt of the information.

27

Concurrent with clinical trials, companies usually complete additional animal studies and must also develop additional information about the biological characteristics of the product candidate and finalize a process for manufacturing the drug product in commercial quantities in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing quality batches of the product candidate and manufacturers must develop, among other things, methods for testing the identity, strength, quality and purity of the final drug product. Additionally, appropriate packaging must be selected and tested, and stability studies must be conducted to demonstrate that the product candidate does not undergo unacceptable deterioration over its shelf life and to identify appropriate storage conditions for the product candidate.

BLA Submission and Review by the FDA

We intend to seek data exclusivity or market exclusivity for vidutolimod. Assuming successful completion of the required clinical testing, the results of the preclinical studies and clinical trials, together with detailed information relating to the product’s chemistry, manufacture, controls and proposed labeling, among other things, are submitted to the FDA as part of a BLA requesting approval to market the product for one or more indications. A BLA is a request for approval to market a new biologic for one or more specified indications. The BLA must include all relevant data available from pertinent pre-clinical and clinical studies, including negative or ambiguous results as well as positive findings, together with detailed information relating to the product’s chemistry, manufacturing, controls, and proposed labeling, among other things. Data may come from company-sponsored clinical trials intended to test the safety and efficacy of a product’s use or from a number of alternative sources, including studies initiated by investigators. To support marketing approval, the data submitted must be sufficient in quality and quantity to establish the safety, purity and potency of the investigational product to the satisfaction of the FDA. FDA approval of a BLA must be obtained before a biologic may be marketed in the United States.

In addition, under the Pediatric Research Equity Act (“PREA”), a BLA or supplement to a BLA must contain data to assess the safety and effectiveness of the biological product candidate for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The Food and Drug Administration Safety and Innovation Act requires that a sponsor who is planning to submit a marketing application for a biological product that includes a new clinically active component, new indication, new dosage form, new dosing regimen or new route of administration submit an initial Pediatric Study Plan within sixty days after an end-of-Phase 2 meeting or as may be agreed between the sponsor and FDA. Unless otherwise required by regulation, PREA does not apply to any biological product for an indication for which orphan designation has been granted.

The FDA reviews all submitted BLAs before it accepts them for filing, and may request additional information rather than accepting the BLA for filing. The FDA must make a decision on accepting a BLA for filing within 60 days of receipt, and such decision could include a refusal to file by the FDA. Once the submission is accepted for filing, the FDA begins an in-depth substantive review of the BLA. The FDA reviews a BLA to determine, among other things, whether the product is safe, pure and potent and whether the facility in which it is manufactured, processed, packaged or held meets standards designed to assure the product’s continued safety, quality and purity. Under the goals and polices agreed to by the FDA under the Prescription Drug User Fee Act (“PDUFA”), the FDA targets ten months, from the filing date, in which to complete its initial review of an original BLA and respond to the applicant, and six months from the filing date of an original BLA filed for priority review. The FDA does not always meet its PDUFA goal dates for standard or priority BLAs, and the review process is often extended by FDA requests for additional information or clarification.

Further, under PDUFA, as amended, each BLA must be accompanied by a user fee, and the sponsor of an approved BLA is also subject to an annual program fee. FDA adjusts the PDUFA user fees on an annual basis. Fee waivers or reductions may be available in certain circumstances, including a waiver of the application fee for the first application filed by a small business. Additionally, no user fees are assessed on BLAs for products designated as orphan drugs, unless the product also includes a non-orphan indication.

28

The FDA may refer an application for a biologic to an advisory committee. An advisory committee is a panel of independent experts, including clinicians and other scientific experts, which reviews, evaluates and provides a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions.

Before approving a BLA, the FDA typically will inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. Additionally, before approving a BLA, the FDA may inspect one or more clinical trial sites to assure compliance with GCP and other requirements and the integrity of the clinical data submitted to the FDA.

The FDA also may require submission of a Risk Evaluation and Mitigation Strategy (“REMS”) as a condition for approving the BLA to ensure that the benefits of the product outweigh its risks. The REMS could include medication guides, physician communication plans, assessment plans, and/or elements to assure safe use, such as restricted distribution methods, patient registries, or other risk-minimization tools.

After evaluating the BLA and all related information, including the advisory committee recommendation, if any, and inspection reports regarding the manufacturing facilities and clinical trial sites, the FDA may issue an approval letter, or, in some cases, a Complete Response Letter. A Complete Response Letter indicates that the review cycle of the application is complete and the application is not ready for approval. A Complete Response Letter will usually describe all of the deficiencies that the FDA has identified in the BLA, except that where the FDA determines that the data supporting the application are inadequate to support approval, the FDA may issue the Complete Response Letter without first conducting required inspections, testing submitted product lots, and/or reviewing proposed labeling. In issuing the Complete Response Letter, the FDA may recommend actions that the applicant might take to place the BLA in condition for approval, including requests for additional information or clarification. Even with submission of this additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval. If and when those conditions have been met to the FDA’s satisfaction, the FDA will typically issue an approval letter. An approval letter authorizes commercial marketing of the product with specific prescribing information for specific indications.

Even if the FDA approves a product, depending on the specific risk(s) to be addressed, the FDA may limit the approved indications for use of the product, require that contraindications, warnings or precautions be included in the product labeling, require that post-approval studies, including Phase 4 clinical trials, be conducted to further assess a product’s safety after approval, require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution and use restrictions or other risk management mechanisms under a REMS, which can materially affect the potential market and profitability of the product. The FDA may prevent or limit further marketing of a product based on the results of post-marketing studies or surveillance programs. After approval, some types of changes to the approved product, such as adding new indications, manufacturing changes, and additional labeling claims, are subject to further testing requirements and FDA review and approval.

Expedited Development and Review Programs for Biologics

The FDA maintains several programs intended to facilitate and expedite development and review of new drugs and biologics to address unmet medical needs in the treatment of serious or life-threatening diseases or conditions. These programs include Fast Track designation, Breakthrough Therapy designation, priority review and Accelerated Approval.

A new biologic is eligible for Fast Track designation if it is intended to treat a serious or life-threatening disease or condition and demonstrates the potential to address unmet medical needs for such disease or condition. Fast

29

Track designation applies to the combination of the product and the specific indication for which it is being studied. Fast Track designation provides increased opportunities for sponsor interactions with the FDA during preclinical and clinical development, in addition to the potential for rolling review once a marketing application is filed, meaning that the FDA may consider for review sections of the BLA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the BLA, the FDA agrees to accept sections of the BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the BLA.

In addition, a new drug or biological product may be eligible for Breakthrough Therapy designation if it is intended to treat a serious or life-threatening disease or condition and preliminary clinical evidence indicates that the biologic, alone or in combination with or more other drugs or biologics, may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. Breakthrough Therapy designation provides all the features of Fast Track designation in addition to intensive guidance on an efficient development program beginning as early as Phase 1, and FDA organizational commitment to expedited development, including involvement of senior managers and experienced review staff in a cross-disciplinary review, where appropriate.

Any product submitted to the FDA for approval, including a product with Fast Track or Breakthrough Therapy designation, may also be eligible for additional FDA programs intended to expedite the review and approval process, including priority review and Accelerated Approval. A product is eligible for priority review if it is intended to treat a serious or life-threatening disease or condition, and if approved, would provide a significant improvement in safety or effectiveness. For original BLAs, priority review designation means the FDA’s goal is to take action on the marketing application within six months of the 60-day filing date (compared with ten months under standard review).

A product intended to treat serious or life-threatening diseases or conditions may receive Accelerated Approval upon a determination that the product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than on irreversible morbidity or mortality which is reasonably likely to predict an effect on irreversible morbidity or mortality or other clinical benefit, taking into account the severity, rarity, or prevalence of the condition and the availability or lack of alternative treatments.

Accelerated Approval is usually contingent on a sponsor’s agreement to conduct additional post-approval studies to verify and describe the product’s clinical benefit. The FDA may withdraw approval of a drug or biologic approved under Accelerated Approval if, for example, the sponsor fails to conduct the confirmatory trials in a timely manner or the confirmatory trial fails to verify the predicted clinical benefit of the product. In addition, for products being considered for Accelerated Approval, the FDA currently requires, unless otherwise informed by the FDA, that all advertising and promotional materials that are intended for dissemination or publication within 120 days following marketing approval be submitted to the agency for review during the pre-approval review period, and that after 120 days following marketing approval, all advertising and promotional materials must be submitted at least 30 days prior to the intended time of initial dissemination or publication.

Fast Track designation, Breakthrough Therapy designation, priority review and Accelerated Approval do not change the scientific or medical standards for approval or the quality of evidence necessary to support approval but may expedite the development or review process.

Orphan Designation and Exclusivity

Under the Orphan Drug Act, the FDA may grant orphan drug designation (“ODD”) to a drug or biologic intended to treat a rare disease or condition, defined as a disease or condition with either a patient population of fewer than 200,000 individuals in the United States, or a patient population greater of than 200,000 individuals in the United States when there is no reasonable expectation that the cost of developing and making available the drug or

30

biologic in the United States will be recovered from sales in the United States of that drug or biologic. ODD must be requested before submitting a BLA. After the FDA grants ODD, the generic identity of the therapeutic agent and its potential orphan use are disclosed publicly by the FDA.

If a product that has received ODD and subsequently receives the first FDA approval for a particular clinically active component for the disease for which it has such designation, the product is entitled to orphan product exclusivity, which means that the FDA may not approve any other applications, including a full BLA, to market the same biologic for the same indication for seven years from the approval of the BLA, except in limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity or if the FDA finds that the holder of the orphan drug exclusivity has not shown that it can assure the availability of sufficient quantities of the orphan drug to meet the needs of patients with the disease or condition for which the drug was designated. Orphan drug exclusivity does not prevent the FDA from approving a different drug or biologic for the same disease or condition, or the same drug or biologic for a different disease or condition. Among the other benefits of ODD are tax credits for certain research and a waiver of the BLA application user fee.

A designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received ODD. In addition, orphan drug exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantities of the product to meet the needs of patients with the rare disease or condition.

U.S. Post-Approval Requirements for Biologics

Drugs and biologics manufactured or distributed pursuant to FDA approvals are subject to pervasive and continuing regulation by the FDA, including, among other things, requirements relating to recordkeeping, periodic reporting, product sampling and distribution, applicable product tracking and tracing requirements, reporting of adverse experiences with the product, complying with promotion and advertising requirements, which include restrictions on promoting products for unapproved uses or patient populations (known as “off-label use”) and limitations on industry-sponsored scientific and educational activities. Although physicians may prescribe approved products for off-label uses, manufacturers may not market or promote such uses. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses, including not only by Company employees but also by agents of the Company or those speaking on the Company’s behalf, and a company that is found to have improperly promoted off-label uses may be subject to significant liability. Failure to comply with these requirements can result in, among other things, adverse publicity, warning letters, corrective advertising and potential civil and criminal penalties, including liabilities under the False Claims Act where products carry reimbursement under federal health care programs. Promotional materials for approved biologics must be submitted to the FDA in conjunction with their first use or first publication. Further, if there are any modifications to the product, including changes in indications, labeling or manufacturing processes or facilities, the applicant may be required to submit and obtain FDA approval of a new BLA or BLA supplement, which may require the development of additional data or preclinical studies and clinical trials.

The FDA may impose a number of post-approval requirements as a condition of approval of a BLA. For example, the FDA may require post-market testing, including Phase 4 clinical trials, and surveillance to further assess and monitor the product’s safety and effectiveness after commercialization.

In addition, drug and biologics manufacturers and their subcontractors involved in the manufacture and distribution of approved products are required to register their establishments with the FDA and certain state agencies and are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with ongoing regulatory requirements, including cGMP, which impose certain procedural and documentation requirements upon us and our contract manufacturers. Changes to the manufacturing process are strictly regulated, and, depending on the significance of the change, may require prior FDA approval before

31

being implemented. FDA regulations also require investigation and correction of any deviations from cGMP and impose reporting requirements upon us and any third-party manufacturers that we may decide to use. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain compliance with cGMP and other aspects of regulatory compliance. Failure to comply with statutory and regulatory requirements can subject a manufacturer to possible legal or regulatory action, such as warning letters, suspension of manufacturing, product seizures, injunctions, civil penalties or criminal prosecution. There is also a continuing, annual program fee for any marketed product.

The FDA may withdraw approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information, requirements for post-market studies or clinical trials to assess new safety risks, or imposition of distribution or other restrictions under a REMS. Other potential consequences include, among other things:

• restrictions on the marketing or manufacturing of the product, complete withdrawal of the product from the market or product recalls;

• safety alerts, Dear Healthcare Provider letters, press releases or other communications containing warnings or other safety information about the product;

• mandated modification of promotional materials and labeling and issuance of corrective information;

• fines, warning letters, or untitled letters;

• holds on clinical trials;

• refusal of the FDA to approve applications or supplements to approved applications, or suspension or revocation of product approvals;

• product seizure or detention, or refusal to permit the import or export of products;

• injunctions or the imposition of civil or criminal penalties; and

• consent decrees, corporate integrity agreements, debarment or exclusion from federal healthcare programs.

Biosimilars and Exclusivity

The Affordable Care Act, signed into law in 2010, includes a subtitle called the Biologics Price Competition and Innovation Act (“BPCIA”), which created an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with an FDA-licensed reference biological product. The FDA has issued several guidance documents outlining an approach to review and approval of biosimilars. Biosimilarity, which requires that there be no clinically meaningful differences between the biological product and the reference product in terms of safety, purity, and potency, can be shown through analytical studies, animal studies, and a clinical trial or studies. Interchangeability requires that a product is biosimilar to the reference product and the product must demonstrate that it can be expected to produce the same clinical results as the reference product in any given patient and, for products that are administered multiple times to an individual, the biologic and the reference biologic may be alternated or switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic.

Under the BPCIA, an application for a biosimilar product may not be submitted to the FDA until four years following the date that the reference product was first licensed by the FDA. In addition, the approval of a biosimilar product may not be made effective by the FDA until 12 years from the date on which the reference product was first licensed. During this 12-year period of exclusivity, another company may still market a competing version of the reference product if the FDA approves a full BLA for the competing product containing

32

that applicant’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of its product. The BPCIA also created certain exclusivity periods for biosimilars approved as interchangeable products. At this juncture, it is unclear whether products deemed “interchangeable” by the FDA will, in fact, be readily substituted by pharmacies, which are governed by state pharmacy law.

A biological product can also obtain pediatric market exclusivity in the United States. Pediatric exclusivity, if granted, adds six months to existing exclusivity periods and patent terms. This six-month exclusivity, which runs from the end of other exclusivity protection or patent term, may be granted based on the voluntary completion of a pediatric trial in accordance with an FDA-issued “Written Request” for such a trial.

The BPCIA is complex and continues to be interpreted and implemented by the FDA. In addition, government proposals have sought to reduce the 12-year reference product exclusivity period. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. As a result, the ultimate impact, implementation, and regulatory interpretation of the BPCIA remain subject to significant uncertainty.

Other regulatory matters

Manufacturing, sales, promotion and other activities of product candidates following product approval, where applicable, or commercialization are also subject to regulation by numerous regulatory authorities in the United States in addition to the FDA, which may include the Centers for Medicare & Medicaid Services (“CMS”), other divisions of the Department of Health and Human Services (“HHS”), the Department of Justice, the Drug Enforcement Administration, the Consumer Product Safety Commission, the Federal Trade Commission, the Occupational Safety & Health Administration, the Environmental Protection Agency and state and local governments and governmental agencies.

Other healthcare laws

Healthcare providers, physicians, and third-party payors will play a primary role in the recommendation and prescription of any products for which we obtain marketing approval. Our business operations and any current or future arrangements with third-party payors, healthcare providers and physicians may expose us to broadly applicable fraud and abuse and other healthcare laws and regulations that may constrain the business or financial arrangements and relationships through which we develop, market, sell and distribute any drugs for which we obtain marketing approval. In the United States, these laws include, without limitation, state and federal anti-kickback, fraud and abuse, false claims, and transparency laws and regulations related to drug pricing and payments and other transfers of value made to physicians and other healthcare providers. If our operations are found to be in violation of any of such laws or any other governmental regulations that apply, we may be subject to penalties, including, without limitation, administrative, civil and criminal penalties, damages, fines, disgorgement, the curtailment or restructuring of operations, integrity oversight and reporting obligations, exclusion from participation in federal and state healthcare programs and responsible individuals may be subject to imprisonment.The distribution of biological products is subject to additional requirements and regulations, including extensive record-keeping, licensing, storage and security requirements intended to prevent the unauthorized sale of pharmaceutical products.

The scope and enforcement of each of these laws is uncertain and subject to rapid change in the current environment of healthcare reform, especially in light of the lack of applicable precedent and regulations. For example, On November 20, 2020, the U.S. Department of Health and Human Services Office of Inspector General, or OIG, finalized further modifications to the federal Anti-Kickback Statute. Under the final rules, OIG added safe harbor protections under the Anti-Kickback Statute for certain coordinated care and value-based arrangements among clinicians, providers, and others. Pursuant to an order entered by the U.S. District Court for the District of Columbia, the portion of the rule eliminating safe harbor protection for certain rebates related to the sale or purchase of a pharmaceutical product from a manufacturer to a plan sponsor under Medicare Part D

33

has been delayed to January 1, 2023. Implementation of the this change and new safe harbors for point-of-sale reductions in price for prescription pharmaceutical products and pharmacy benefit manager service fees are currently under review by the Biden administration and may be amended or repealed. Federal and state enforcement bodies have recently increased their scrutiny of interactions between healthcare companies and healthcare providers, which has led to a number of investigations, prosecutions, convictions and settlements in the healthcare industry. It is possible that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of these laws or any other related governmental regulations that may apply to us, we may be subject to significant civil, criminal and administrative penalties, damages, fines, imprisonment, disgorgement, exclusion from government funded healthcare programs, such as Medicare and Medicaid, reputational harm, additional oversight and reporting obligations if we become subject to a corporate integrity agreement or similar settlement to resolve allegations of non-compliance with these laws and the curtailment or restructuring of our operations. If any of the physicians or other healthcare providers or entities with whom we expect to do business are found to be not in compliance with applicable laws, they may be subject to similar actions, penalties and sanctions. Ensuring business arrangements comply with applicable healthcare laws, as well as responding to possible investigations by government authorities, can be time- and resource-consuming and can divert a company’s attention from its business.

Coverage and Reimbursement

In the United States and markets in other countries, patients who are prescribed treatments for their conditions and providers performing the prescribed services generally rely on third-party payors to reimburse all or part of the associated healthcare costs. Thus, even if a product candidate is approved, sales of the product will depend, in part, on the extent to which third-party payors, including government health programs in the United States such as Medicare and Medicaid, commercial health insurers and managed care organizations, provide coverage, and establish adequate reimbursement levels for, the product. In the United States, no uniform policy of coverage and reimbursement for drug products exists among third-party payors, but the principal decisions about reimbursement for new medicines are typically made by CMS. CMS decides whether and to what extent a new medicine will be covered and reimbursed under Medicare and private payors tend to follow CMS to a substantial degree. However, coverage and reimbursement for drug products can differ significantly from payor to payor. The process for determining whether a third-party payor will provide coverage for a product may be separate from the process for setting the price or reimbursement rate that the payor will pay for the product once coverage is approved. Third-party payors are increasingly challenging the prices charged, examining the medical necessity, and reviewing the cost-effectiveness of medical products and services and imposing controls to manage costs. Third-party payors may limit coverage to specific products on an approved list, also known as a formulary, which might not include all of the approved products for a particular indication.

In order to secure coverage and reimbursement for any product that might be approved for sale, a company may need to conduct expensive pharmacoeconomic studies in order to demonstrate the medical necessity and cost-effectiveness of the product, in addition to the costs required to obtain FDA or other comparable regulatory approvals. Additionally, companies may also need to provide discounts to purchasers, private health plans or government healthcare programs. Factors payors consider in determining reimbursement are based on whether the product is:

• a covered benefit under its health plan;

• safe, effective and medically necessary;

• appropriate for the specific patient;

• cost-effective; and

• neither experimental nor investigational.

Nonetheless, product candidates may not be considered medically necessary or cost effective. A decision by a third-party payor not to cover a product could reduce physician utilization once the product is approved and have

34

a material adverse effect on sales, our operations and financial condition. Additionally, a third-party payor’s decision to provide coverage for a product does not imply that an adequate reimbursement rate will be approved. Further, one payor’s determination to provide coverage for a product does not assure that other payors will also provide coverage and reimbursement for the product, and the level of coverage and reimbursement can differ significantly from payor to payor.

The containment of healthcare costs has become a priority of federal, state and foreign governments, and the prices of products have been a focus in this effort. Governments have shown significant interest in implementing cost-containment programs, including price controls, restrictions on reimbursement and requirements for substitution of generic products. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit a company’s revenue generated from the sale of any approved products. Coverage policies and third-party payor reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which a company or its collaborators receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Healthcare Reform

In the United States and some foreign jurisdictions, there have been, and likely will continue to be, a number of legislative and regulatory changes and proposed changes regarding the healthcare system directed at broadening the availability of healthcare, improving the quality of healthcare, and containing or lowering the cost of healthcare. For example, in March 2010, the United States Congress enacted the Affordable Care Act, which, among other things, includes changes to the coverage and payment for products under government health care programs. The Affordable Care Act includes provisions of importance to our potential product candidate that:

• created an annual, nondeductible fee on any entity that manufactures or imports specified branded prescription drugs and biologic products, apportioned among these entities according to their market share in certain government healthcare programs;

• expanded eligibility criteria for Medicaid programs by, among other things, allowing states to offer Medicaid coverage to certain individuals with income at or below 133% of the federal poverty level, thereby potentially increasing a manufacturer’s Medicaid rebate liability;

• expanded manufacturers’ rebate liability under the Medicaid Drug Rebate Program by increasing the minimum rebate for both branded and generic drugs and revising the definition of “average manufacturer price,” or AMP, for calculating and reporting Medicaid drug rebates on outpatient prescription drug prices;

• addressed a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for drugs that are inhaled, infused, instilled, implanted or injected;

• expanded the types of entities eligible for the 340B drug discount program;

• established the Medicare Part D coverage gap discount program by requiring manufacturers to provide point-of-sale-discounts off the negotiated price of applicable brand drugs to eligible beneficiaries during their coverage gap period as a condition for the manufacturers’ outpatient drugs to be covered under Medicare Part D; and

• created a Patient-Centered Outcomes Research Institute to oversee, identify priorities in, and conduct comparative clinical effectiveness research, along with funding for such research.

Since its enactment, there have been numerous judicial, administrative, executive, and legislative challenges to certain aspects of the ACA, and we expect there will be additional challenges and amendments to the ACA in the future. Various portions of the ACA are currently undergoing legal and constitutional challenges in the United States Supreme Court; the former Trump Administration issued various Executive Orders eliminating cost

35

sharing subsidies and various provisions that would impose a fiscal burden on states or a cost, fee, tax, penalty or regulatory burden on individuals, healthcare providers, health insurers, or manufacturers of pharmaceuticals or medical devices; and Congress has introduced several pieces of legislation aimed at significantly revising or repealing the ACA. The implementation of the ACA is ongoing, the law appears likely to continue the downward pressure on pharmaceutical pricing, especially under the Medicare program, and may also increase our regulatory burdens and operating costs. Litigation and legislation related to the ACA are likely to continue, with unpredictable and uncertain results.

Other legislative changes have been proposed and adopted in the United States since the Affordable Care Act was enacted. In August 2011, the Budget Control Act of 2011, among other things, included aggregate reductions of Medicare payments to providers of 2% per fiscal year, which went into effect in April 2013 and, due to subsequent legislative amendments to the statute, will remain in effect through 2029 unless additional Congressional action is taken. The Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) which was signed into law on March 27, 2020, designed to provide financial support and resources to individuals and businesses affected by the COVID-19 pandemic, as well as subsequent legislation, suspended these reductions from May 1, 2020 through March 31, 2021, and extended the sequester by one year, through 2030. Proposed legislation, if passed, would extend this suspension until the end of the pandemic. In addition, in January 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, further reduced Medicare payments to several providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

Moreover, payment methodologies may be subject to changes in healthcare legislation and regulatory initiatives. For example, CMS may develop new payment and delivery models, such as bundled payment models. In addition, recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their commercial products, which has resulted in several Congressional inquiries and proposed and enacted state and federal legislation designed to, among other things, bring more transparency to product pricing, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for pharmaceutical products. For example, at the federal level, the former Trump administration’s budget proposal for fiscal year 2021 included a $135 billion allowance to support legislative proposals seeking to reduce drug prices, increase competition, lower out-of-pocket drug costs for patients, and increase patient access to lower-cost generic and biosimilar drugs. On March 10, 2020, the former Trump administration sent “principles” for drug pricing to Congress, calling for legislation that would, among other things, cap Medicare Part D beneficiary out-of-pocket pharmacy expenses, provide an option to cap Medicare Part D beneficiary monthly out-of-pocket expenses, and place limits on pharmaceutical price increases. Further, the former Trump administration also previously released a “Blueprint” to lower drug prices and reduce out of pocket costs of drugs that contains additional proposals to increase manufacturer competition, increase the negotiating power of certain federal healthcare programs, incentivize manufacturers to lower the list price of their products and reduce the out-of-pocket costs of drug products paid by consumers. The U.S. Department of Health and Human Services, or HHS, has already implemented certain measures. For example, in May 2019, CMS issued a final rule to allow Medicare Advantage Plans the option of using step therapy for Part B drugs beginning January 1, 2020. However, it is unclear whether the Biden administration will challenge, reverse, revoke or otherwise modify these executive and administrative actions. In addition, individual states in the United States have also increasingly passed legislation and implemented regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing.

On May 30, 2018, the Right to Try Act was signed into law. The law, among other things, provides a federal framework for certain patients to access certain investigational new drug products that have completed a Phase 1 clinical trial and that are undergoing investigation for FDA approval. Under certain circumstances, eligible patients can seek treatment without enrolling in clinical trials and without obtaining FDA permission under the

36

FDA expanded access program. There is no obligation for a drug manufacturer to make its drug products available to eligible patients through expanded access, but under the 21st Century Cures Act, the manufacturer must develop an internal policy and respond to patient requests according to that policy. We review each individual request for access , and may or may not provide access depending upon the facts of each request. Checkmate has adopted an Expanded Access Policy which is available on our website.

Outside the United States, ensuring coverage and adequate payment for a product also involves challenges. Pricing of prescription pharmaceuticals is subject to government control in many countries. Pricing negotiations with government authorities can extend well beyond the receipt of regulatory approval for a product and may require a clinical trial that compares the cost-effectiveness of a product to other available therapies. The conduct of such a clinical trial could be expensive and result in delays in commercialization.

In the European Union, pricing and reimbursement schemes vary widely from country to country. Some countries provide that products may be marketed only after a reimbursement price has been agreed. Some countries may require the completion of additional studies that compare the cost-effectiveness of a particular product candidate to currently available therapies or so-called health technology assessments, in order to obtain reimbursement or pricing approval. For example, the European Union provides options for its member states to restrict the range of products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. European Union member states may approve a specific price for a product or they may instead adopt a system of direct or indirect controls on the profitability of the company placing the product on the market. Other member states allow companies to fix their own prices for products, but monitor and control prescription volumes and issue guidance to physicians to limit prescriptions. Recently, many countries in the European Union have increased the amount of discounts required on pharmaceuticals and these efforts could continue as countries attempt to manage healthcare expenditures, especially in light of the severe fiscal and debt crises experienced by many countries in the European Union. The downward pressure on healthcare costs in general, particularly prescription products, has become intense. As a result, increasingly high barriers are being erected to the entry of new products. Political, economic and regulatory developments may further complicate pricing negotiations, and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various European Union member states, and parallel trade, i.e., arbitrage between low-priced and high-priced member states, can further reduce prices. There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any products, if approved in those countries.

Compliance with other federal and state laws or requirements; changing legal requirements

If any products that we may develop are made available to authorized users of the Federal Supply Schedule of the General Services Administration, additional laws and requirements apply. Products must meet applicable child-resistant packaging requirements under the U.S. Poison Prevention Packaging Act. Manufacturing, labeling, packaging, distribution, sales, promotion and other activities also are potentially subject to federal and state consumer protection and unfair competition laws, among other requirements to we may be subject.

The distribution of pharmaceutical products is subject to additional requirements and regulations, including extensive record-keeping, licensing, storage and security requirements intended to prevent the unauthorized sale of pharmaceutical products.

The failure to comply with any of these laws or regulatory requirements subjects firms to possible legal or regulatory action. Depending on the circumstances, failure to meet applicable regulatory requirements can result in criminal prosecution, fines or other penalties, injunctions, exclusion from federal healthcare programs, requests for recall, seizure of products, total or partial suspension of production, denial or withdrawal of product approvals, relabeling or repackaging, or refusal to allow a firm to enter into supply contracts, including government contracts. Any claim or action against us for violation of these laws, even if we successfully defend

37

against it, could cause us to incur significant legal expenses and divert our management’s attention from the operation of our business. Prohibitions or restrictions on marketing, sales or withdrawal of future products marketed by us could materially affect our business in an adverse way.

Changes in regulations, statutes or the interpretation of existing regulations could impact our business in the future by requiring, for example: (i) changes to our manufacturing arrangements; (ii) additions or modifications to product labeling or packaging; (iii) the recall or discontinuation of our products; or (iv) additional record-keeping requirements. If any such changes were to be imposed, they could adversely affect the operation of our business.

Other U.S. Environmental, Health and Safety Laws and Regulations

We may be subject to numerous environmental, health and safety laws and regulations, including those governing laboratory procedures and the handling, use, storage, treatment and disposal of hazardous materials and wastes. From time to time and in the future, our operations may involve the use of hazardous and flammable materials, including chemicals and biological materials, and may also produce hazardous waste products. Even if we contract with third parties for the disposal of these materials and waste products, we cannot completely eliminate the risk of contamination or injury resulting from these materials. In the event of contamination or injury resulting from the use or disposal of our hazardous materials, we could be held liable for any resulting damages, and any liability could exceed our resources. We also could incur significant costs associated with civil or criminal fines and penalties for failure to comply with such laws and regulations.

We maintain workers’ compensation insurance to cover us for costs and expenses we may incur due to injuries to our employees, but this insurance may not provide adequate coverage against potential liabilities. However, we do not maintain insurance for environmental liability or toxic tort claims that may be asserted against us.

In addition, we may incur substantial costs in order to comply with current or future environmental, health and safety laws and regulations. Current or future environmental laws and regulations may impair our research, development or production efforts. In addition, failure to comply with these laws and regulations may result in substantial fines, penalties or other sanctions.

Government Regulation of Drugs Outside of the United States

To market any product outside of the United States, we would need to comply with numerous and varying regulatory requirements of other countries regarding safety and efficacy and governing, among other things, clinical trials, marketing authorization or identification of an alternate regulatory pathway, manufacturing, commercial sales and distribution of our products. For instance, in the European Economic Area (the “EEA”) (comprised of the 27 EU Member States plus Iceland, Liechtenstein and Norway, medicinal products must be authorized for marketing by using either the centralized authorization procedure or a national authorization procedures.

• Centralized procedure—If pursuing marketing authorization of a product candidate for a therapeutic indication under the centralized procedure, following the opining of the EMA’s Committee for Medicinal Products for Human Use, (“CHMP”), the European Commission issues a single marketing authorization valid throughout the EEA. The centralized procedure is compulsory for human medicines derived from biotechnology processes or advanced therapy medicinal products (gene therapy, somatic cell therapy and tissue engineered products), products that contain a new active substance indicated for the treatment of certain diseases, such as HIV/AIDS, cancer, neurodegenerative disorders, diabetes, autoimmune diseases and other immune dysfunctions, viral diseases, and officially designated orphan medicines. For medicines that do not fall within these categories, an applicant has the option of submitting an application for a centralized marketing authorization to the EMA, as long as the medicine concerned contains a new active substance not yet authorized in the EEA, is a significant

38

therapeutic, scientific or technical innovation, or if its authorization would be in the interest of public health in the EEA. Under the centralized procedure the maximum timeframe for the evaluation of an MAA by the EMA is 210 days, excluding clock stops, when additional written or oral information is to be provided by the applicant in response to questions asked by the CHMP. Clock stops may extend the timeframe of evaluation of a MA application considerably beyond 210 days. Where the CHMP gives a positive opinion, the EMA provides the opinion together with supporting documentation to the European Commission, who make the final decision to grant a marketing authorization, which is issued within 67 days of receipt of the EMA’s recommendation. Accelerated assessment might be granted by the CHMP in exceptional cases, when a medicinal product is expected to be of a major public health interest, particularly from the point of view of therapeutic innovation. The timeframe for the evaluation of an MAA under the accelerated assessment procedure is 150 days, excluding clock stops.

• National authorization procedures—There are also two other possible routes to authorize products for therapeutic indications in several countries, which are available for products that fall outside the scope of the centralized procedure:

• Decentralized procedure—Using the decentralized procedure, an applicant may apply for simultaneous authorization in more than one EEA country of medicinal products that have not yet been authorized in any EEA country and that do not fall within the mandatory scope of the centralized procedure.

• Mutual recognition procedure—In the mutual recognition procedure, a medicine is first authorized in one EEA Member State, in accordance with the national procedures of that country. Following this, additional marketing authorizations can be sought from other EEA countries in a procedure whereby the countries concerned recognize the validity of the original, national marketing authorization.

Now that the UK (which comprises Great Britain and Northern Ireland) has left the EU, Great Britain will no longer be covered by centralized MAs (under the Northern Irish Protocol, centralized MAs will continue to be recognized in Northern Ireland). All medicinal products with a current centralized MA were automatically converted to Great Britain MAs on January 1, 2021. For a period of two years from January 1, 2021, the Medicines and Healthcare products Regulatory Agency (MHRA), the UK medicines regulator, may rely on a decision taken by the European Commission on the approval of a new marketing authorization in the centralized procedure, in order to more quickly grant a new Great Britain MA. A separate application will, however, still be required.

In the EEA, new products for therapeutic indications that are authorized for marketing (i.e., reference products) qualify for eight years of data exclusivity and an additional two years of market exclusivity upon marketing authorization. The data exclusivity period prevents generic or biosimilar applicants from relying on the preclinical and clinical trial data contained in the dossier of the reference product when applying for a generic or biosimilar marketing authorization in the EEA during a period of eight years from the date on which the reference product was first authorized in the EEA. The market exclusivity period prevents a successful generic or biosimilar applicant from commercializing its product in the EEA until ten years have elapsed from the initial authorization of the reference product in the EEA. The ten-year market exclusivity period can be extended to a maximum of eleven years if, during the first eight years of those ten years, the marketing authorization holder obtains an authorization for one or more new therapeutic indications which, during the scientific evaluation prior to their authorization, are held to bring a significant clinical benefit in comparison with existing therapies.

The criteria for designating an “orphan medicinal product” in the EEA are similar in principle to those in the United States. In the EEA a medicinal product may be designated as orphan if (1) it is intended for the diagnosis, prevention or treatment of a life-threatening or chronically debilitating condition; (2) either (a) such condition affects no more than five in 10,000 persons in the EU when the application is made, or (b) the product, without the benefits derived from orphan status, would not generate sufficient return in the EU to justify the necessary investment in its development; and (3) there exists no satisfactory method of diagnosis, prevention or treatment of such condition authorized for marketing in the EU, or if such a method exists, the product will be of

39

significant benefit to those affected by the condition. Orphan medicinal products are eligible for financial incentives such as reduction of fees or fee waivers and are, upon grant of a marketing authorization, entitled to ten years of market exclusivity for the approved therapeutic indication. During this ten-year orphan market exclusivity period, no marketing authorization application shall be accepted, and no marketing authorization shall be granted for a similar medicinal product for the same indication. A “similar medicinal product” is defined as a medicinal product containing a similar active substance or substances as contained in an authorized orphan medicinal product, and which is intended for the same therapeutic indication. An orphan product can also obtain an additional two years of market exclusivity in the EU for pediatric studies. The ten-year market exclusivity may be reduced to six years if, at the end of the fifth year, it is established that the product no longer meets the criteria for orphan designation, for example, if the product is sufficiently profitable not to justify maintenance of market exclusivity. Additionally, marketing authorization may be granted to a similar product for the same indication at any time if (i) the second applicant can establish that its product, although similar, is safer, more effective or otherwise clinically superior; (ii) the applicant consents to a second orphan medicinal product application; or (iii) the applicant cannot supply enough orphan medicinal product.

Similar to the United States, the various phases of non-clinical and clinical research in the European Union are subject to significant regulatory controls.

The Clinical Trials Directive 2001/20/EC, the Directive 2005/28/EC on GCP and the related national implementing provisions of the individual EU Member States govern the system for the approval of clinical trials in the European Union. Under this system, an applicant must obtain prior approval from the competent national authority of the EU Member States in which the clinical trial is to be conducted. Furthermore, the applicant may only start a clinical trial at a specific trial site after the competent ethics committee has issued a favorable opinion. The clinical trial application must be accompanied by, among other documents, an investigational medicinal product dossier (the Common Technical Document) with supporting information prescribed by Directive 2001/20/EC, Directive 2005/28/EC, where relevant the implementing national provisions of the individual EU Member States and further detailed in applicable guidance documents.

In April 2014, the new Clinical Trials Regulation, (EU) No 536/2014 (Clinical Trials Regulation) was adopted. The Regulation is anticipated to come into application in January 2022. The Clinical Trials Regulation will be directly applicable in all the EU Member States, repealing the current Clinical Trials Directive 2001/20/EC. Conduct of all clinical trials performed in the European Union will continue to be bound by currently applicable provisions until the new Clinical Trials Regulation becomes applicable. The extent to which ongoing clinical trials will be governed by the Clinical Trials Regulation will depend on when the Clinical Trials Regulation becomes applicable and on the duration of the individual clinical trial. If a clinical trial continues for more than three years from the day on which the Clinical Trials Regulation becomes applicable the Clinical Trials Regulation will at that time begin to apply to the clinical trial. The new Clinical Trials Regulation aims to simplify and streamline the approval of clinical trials in the European Union. The main characteristics of the regulation include: a streamlined application procedure via a single-entry point, the Clinical Trials Information System (“CTIS”), a single set of documents to be prepared and submitted for the application as well as simplified reporting procedures for clinical trial sponsors; and a harmonized procedure for the assessment of applications for clinical trials, which is divided in two parts. Part I is assessed by the competent authorities of all EU Member States in which an application for authorization of a clinical trial has been submitted (Member States concerned). Part II is assessed separately by each Member State concerned. Strict deadlines have been established for the assessment of clinical trial applications. The role of the relevant ethics committees in the assessment procedure will continue to be governed by the national law of the concerned EU Member State. However, overall related timelines will be defined by the Clinical Trials Regulation. The Clinical Trials Regulation will only become applicable six months after the European Commission confirms the full functionality of CTIS. Such a confirmation will only occur once CTIS is audited. The CTIS audit is currently planned for December 2020.

The collection and use of personal health data in the European Union, previously governed by the provisions of the Data Protection Directive, is now governed by the General Data Protection Regulation (“GDPR”), which

40

became effective on May 25, 2018. The GDPR has a broad reach, applying not only to those companies that are established in the EU but also to those that offer their goods or services to residents in the EU. If we conduct clinical trial activities in EU members states, we will be subject to the GDPR. The GDPR imposes strict requirements on controllers and processors of personal data, including special protections for “sensitive information” which includes health and genetic information of data subjects residing in the EU. GDPR grants individuals the opportunity to object to the processing of their personal information, allows them to request deletion of personal information in certain circumstances, and provides the individual with an express right to seek legal remedies in the event the individual believes his or her rights have been violated. Further, the GDPR imposes strict rules on the transfer of personal data out of the European Union to the United States or other regions that have not been deemed to offer “adequate” privacy protections. Failure to comply with the requirements of the GDPR and the related national data protection laws of the European Union Member States, which may deviate slightly from the GDPR, may result in fines of up to 4% of global revenues, or €20,000,000, whichever is greater. As a result of the implementation of the GDPR, we may be required to put in place additional mechanisms ensuring compliance with the new data protection rules. Enforcement uncertainty and the costs associated with ensuring GDPR compliance are onerous and may adversely affect our business, financial condition, results of operations and prospects.

Should we utilize third party distributors, compliance with such foreign governmental regulations, including the GDPR would generally be the responsibility of such distributors, who may be independent contractors over whom we have limited control.

Employees, Human Capital Management and Diversity

As of March 29, 2022, we had 30 full-time employees and one part-time employee, including 6 with M.D. and/or Ph.D. degrees. Of these employees, 24 are in research and development and 7 are general and administrative. We have never had a work stoppage, and none of our employees are represented by a labor organization or under any collective-bargaining arrangements. We consider our employee relations to be good.

Our human capital management objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our existing and new employees, advisors and consultants. The principal purposes of our equity and cash incentive plans , along with a comprehensive benefits package and a 401(k) plan, are to attract, retain and reward personnel through the granting of stock-based and cash-based compensation awards.

The Company is an equal opportunity employer, and we are committed to fostering diversity and inclusion within our work environment and beyond. Our efforts are focused on hiring and retaining qualified candidates. The Company is committed to the fair treatment of all candidates and employees, including equal opportunity hiring and advancement practices and policies, and anti-harassment and anti-retaliation policies. We believe that fostering diversity, equity, and inclusion is a key element to discovering, developing, and bringing transformative therapies to patients. As of March 29, 2021, 47% of our workforce and 45% of our leadership (at the Director level and above) were female. In addition, 27% of our workforce and 35% of our leadership (at the Director level and above) were racially or ethnically diverse. We strive to build a representative workforce.

Corporate Information

We were incorporated in July 2015 under the laws of the State of Delaware. Our principal executive offices are located at 245 Main Street, 2nd Floor, Cambridge, MA 02142, and our telephone number is (617) 682-3625. Our website address is www.checkmatepharma.com. The information on our website is not incorporated by reference in this Annual Report on Form 10-K or in any other filings we make with the Securities and Exchange Commission (the “SEC”).

41

Available Information

We make available on or through our website certain reports and amendments to those reports that we file with or furnish to the SEC in accordance with the Securities Exchange Act of 1934, as amended. These include our annual reports on Form 10-K, our quarterly reports on Form 10-Q, and our current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act. We make this information available on or through our website free of charge as soon as reasonably practicable after we electronically file the information with, or furnish it to, the SEC.

A copy of our Corporate Governance Guidelines, Code of Business Conduct and Ethics and the charters of the Audit Committee, Compensation Committee, Nominating and Corporate Governance Committee, and Research and Development Commmitee are posted on our website, www.checkmatepharma.com, under “Investors—Corporate Governance.”

The SEC maintains an Internet website that contains reports, proxy and information statements, and other information regarding us and other issuers that file electronically with the SEC. The SEC’s Internet website address is http://www.sec.gov.

Item 1A. Risk Factors.

In evaluating our Company and our business, careful consideration should be given to the following risk factors, in addition to the other information set forth in this Annual Report on Form 10-K and in other documents that we file with the SEC. Investing in our common stock involves a high degree of risk. If any such risks or uncertainties actually occur, our business, financial condition or operating results could differ materially from the plans, projections and other forward-looking statements included in this Annual Report, including in the foregoing Business section and later in the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and elsewhere in this report and in our other public filings and public statements. The trading price of our common stock could decline due to any of these risks, and as a result, our stockholders may lose all or part of their investment. The risks described below are not intended to be exhaustive and are not the only risks facing the Company. New risk factors can emerge from time to time, and it is not possible to predict the impact that any factor or combination of factors may have on our business, prospects, financial condition or results of operations.

Risks related to our financial position and need for additional capital

We are a clinical-stage biopharmaceutical company with a limited operating history. We have incurred net losses since our inception and anticipate that we will continue to incur substantial and increasing net losses in the foreseeable future. We may never achieve or sustain profitability.

We are a clinical-stage biopharmaceutical company with a limited operating history, and we are relatively early in our development efforts. We have no products approved for commercial sale and have not generated any revenue from product sales to date, and we continue to incur significant research and development and other expenses related to our ongoing operations. Investment in biopharmaceutical product development is highly speculative because it entails substantial upfront capital expenditures and significant risk that any potential product candidate will fail to demonstrate adequate efficacy or an acceptable safety profile, gain marketing approval and become commercially viable. We have financed our operations to date primarily through the sale of equity securities. Since our inception, most of our resources have been dedicated to the preclinical and clinical development of our vidutolimod program and our VLP technology. To date, no drugs based on our VLP technology have been approved. The size of our future net losses will depend, in part, on our future expenses and our ability to generate revenue, if any.

We are not profitable, have never generated any revenue and have incurred losses in each period since our inception. For the years ended December 31, 2020 and 2021, we reported net losses of $36.9 million and

42

$61.4 million, respectively. At December 31, 2021, we had an accumulated deficit of $201.5 million. We anticipate operating losses to continue for the foreseeable future due to, among other things, costs related to conducting clinical trials and third-party contract manufacturing, and our administrative organization. We will require substantial additional financing to fund our operations and to continue to continue our ongoing clinical trials and execute our strategy, and we may pursue a range of options to secure additional capital. Given our cash position and our need to raise substantial additional financing, there is substantial doubt about our ability to continue as a going concern within one year after the date of filing this Annual Report on Form 10-K.

We are exploring various sources of funding including the issuance of additional equity to fund our operations, and we may pursue other sources of funding, such as debt financings, licensing arrangements and strategic collaborations. To the extent that we raise additional capital through the sale of equity, the ownership interest of our existing shareholders will be diluted and other preferences may be necessary that adversely affect the rights of existing shareholders. If we raise additional funds through strategic collaborations, which may include existing collaboration partners, we may have to relinquish valuable rights to our technologies or product candidates, or, grant licenses or other rights on terms that are not favorable to us. Because our current operating plan does not contain sufficient resources, we will require significant additional external sources of capital to complete the planned clinical program for vidutolimod. If we are unable to raise sufficient capital, we intend to curtail expenses contemplated by the current operating plan, and we may be required to delay, limit, reduce or terminate our product development efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves. If the foregoing plans are unsuccessful and we are unable to continue as a going concern, you could lose all or part of your investment in the company.

Even if we succeed in receiving marketing approval for and commercializing vidutolimod or any other product candidate, we will continue to incur substantial research and development and other expenditures to develop and market additional potential indications or products. We may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. The size of our future net losses will depend, in part, on the rate of future growth of our expenses and our ability to generate revenue. Our prior losses and expected future losses have had and will continue to have an adverse effect on our stockholders’ equity and working capital.

We have never generated any revenue from product sales, and our ability to generate revenue from product sales and become profitable will depend significantly on our success in achieving a number of goals and on other factors.

We have no products approved for commercial sale, have not generated any revenue from product sales, and do not anticipate generating any revenue from product sales until after we have received marketing approval for the commercial sale of a product candidate, if ever. Our ability to generate revenue and achieve profitability depends significantly on our ability to raise sufficient additional funds and our success in achieving a number of goals in a timely manner, including:

• initiating and completing preclinical and clinical development of vidutolimod and future product candidates, including completing enrollment in and obtaining results from our current Phase 2 trial for anti-PD-1 refractory melanoma, our current randomized Phase 2/3 trial for first-line melanoma, our current Phase 2 proof of concept trial in advanced head and neck squamous cell carcinoma and our currently anticipated Phase 2 proof of concept, multi-indication trial in CSCC and MCC;

• obtainingregulatory and marketing approvals for vidutolimod and future product candidates for which we complete clinical trials;

• achieving and maintaining compliance with all regulatory requirements applicable to vidutolimod or any other product candidates;

• establishing and maintaining commercially viable supply and manufacturing relationships with third parties for vidutolimod and future product candidates;

43

• launching and commercializing vidutolimod, if approved, and future product candidates for which we obtain marketing approvals, either directly or with a collaborator or distributor;

• obtaining market acceptance of vidutolimod, if approved, and future product candidates as viable treatment options by patients, the medical community and third-party payors;

• addressing any competing technological and market developments;

• identifying, assessing, acquiring and developing new product candidates;

• negotiating favorable terms in any collaboration, licensing, or other arrangements into which we may enter;

• obtaining, maintaining, protecting, and expanding our portfolio of intellectual property rights, including patents, trade secrets, and know-how; and

• attracting, hiring, and retaining qualified personnel.

Even if vidutolimod or any future product candidates that we develop are approved for commercial sale, we anticipate incurring significant costs associated with commercializing any such product candidate. Our expenses could increase beyond expectations if we are required by the FDA or comparable foreign regulatory authorities to change our manufacturing processes or assays, or to perform clinical, nonclinical, or other types of studies in addition to those that we currently anticipate.

If we are successful in obtaining regulatory approvals to market vidutolimod or any future product candidates, our revenue will be dependent, in part, upon the size of the markets in the territories for which we gain marketing approval, the accepted price for the product, the ability to get reimbursement at any price, and whether we own the commercial rights for that territory. If the number of our addressable patients is not as significant as we estimate, the indication approved by regulatory authorities is narrower than we expect, the labels for vidutolimod and future product candidates contain significant safety warnings, regulatory authorities impose burdensome or restrictive distribution requirements, or the reasonably accepted patient population for treatment is narrowed by competition, physician choice or treatment guidelines, we may not generate significant revenue from sales of such products, even if approved. If we are not able to generate revenue from the sale of any approved products, we could be prevented from or significantly delayed in achieving profitability.

There is substantial doubt regarding our ability to continue as a going concern. We need to raise significant additional funding, which may not be available on acceptable terms, or at all. Failure to obtain this necessary capital when needed may force us to delay, limit, reduce or terminate our product development efforts, including ongoing clinical trials, research, or other operations.

As of December 31, 2021, our cash, cash equivalents and marketable securities were $70.9 million. Based on our current business plan, there is substantial doubt regarding our ability to continue as a going concern for a period of one year after the date that our financial statements for the year ended December 31, 2021 are issued and we need to raise significant amounts of additional funding to complete all of our ongoing trials and execute on our business plan. Financing may not be available in sufficient amounts or on terms acceptable to us, if at all. Moreover, the terms of any financing may adversely affect the holdings or the rights of our stockholders and the issuance of additional securities, whether equity or debt, by us, or the possibility of such issuance, may cause the market price of our shares to decline. In addition, our efforts to raise additional capital may divert our management from their day-to-day activities, which may adversely affect our ability to develop vidutolimod in a timely manner.

Based on our public float, as of the date of the filing of this Annual Report on Form 10-K, we are only permitted to utilize a “shelf” registration statement, including the registration statement under which our Open Market Sale AgreementSM with Jefferies LLC, is operated, subject to Instruction I.B.6 to Form S-3, which is referred to as the

44

“baby shelf” rule. For so long as our public float is less than $75 million, we may not sell more than the equivalent of one-third of our public float during any 12 consecutive months pursuant to the baby shelf rules. Although alternative public and private transaction structures may be available, these may require additional time and cost, may impose operational restrictions on us, and may not be available on attractive terms.

If we are unable to obtain adequate funding on a timely basis, we may be required to revise our business plan and strategy, which may result in us significantly curtailing, delaying or discontinuing one or more of our clinical trials and our research efforts, or may result in our being unable to expand our operations or otherwise capitalize on our business opportunities. As a result, our business, financial condition and results of operations could be materially affected.

We will require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate our product development, research or commercialization efforts.

Our operations have consumed substantial amounts of cash since inception. We expect to continue to spend substantial amounts to continue the clinical and preclinical development of vidutolimod and future product We will need to obtain substantial additional funds to complete our ongoing clinical trials and achieve our other business objectives. If we are able to gain marketing approval of any product candidate, we will require significant additional amounts of cash in order to launch and commercialize such product. In addition, other unanticipated costs may arise.

Our future capital requirements depend on many factors, including:

• the scope, progress, results, timing and costs of researching and developing vidutolimod and our VLP technology and future product candidates, and conducting preclinical studies and clinical trials, including our current Phase 2 trial for anti-PD-1 refractory melanoma, our current randomized Phase 2/3 trial for first-line melanoma, our current Phase 2 proof of concept trial in advanced head and neck squamous cell carcinoma and our current Phase 2 proof of concept, multi-indication trial in CSCC and MCC, including any unforeseen costs we may incur as a result of trial delays we have experienced or other impacts due to the ongoing global pandemic associated with COVID-19 (the “COVID-19 pandemic”) or otherwise;;

• the timing of, and the costs involved in, obtaining regulatory and marketing approvals for vidutolimod and future product candidates if clinical trials are successful;

• the success of existing or any future collaborations, including the BMS CTCSA and the Regeneron SNLA;;

• the cost of commercialization activities for any approved product, including marketing, sales and distribution costs;

• the cost of manufacturing vidutolimod and future product candidates for clinical trials;

• our ability to establish and maintain strategic licensing or other arrangements and the financial terms of such agreements, including the Kuros License Agreement

• the costs involved in preparing, filing, prosecuting, maintaining, expanding, defending and enforcing patent claims, including litigation costs and the outcome of such litigation;

• the timing, receipt, and amount of sales of, or royalties on, our future products, if any; and

• the emergence, and regulatory approval, of competing cancer therapies and other adverse market developments.

We do not have any committed external source of funds or other support for our development efforts. Until we can generate sufficient product revenue to finance our cash requirements, which we may never do, we expect to

45

finance our future cash needs through a combination of public or private equity offerings, debt financings, collaborations, strategic alliances, licensing arrangements and other marketing or distribution arrangements. We can provide no assurance that we will be able to finance our future cash needs on favorable terms, if at all.

We believe that our existing cash, cash equivalents and available-for-sale investments of $70.9 million as of December 31, 2021 will enable us to fund our operating expenses and capital expenditure requirements through the end of 2022. Because our current operating plan does not contain sufficient resources, we will require additional external sources of capital to complete the planned clinical programs for vidutolimod. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. Because of the uncertainty in securing additional capital, we have concluded that substantial doubt exists with respect to our ability to continue as a going concern within one year after the date of the filing of this Annual Report on Form 10-K.

Because of the numerous risks and uncertainties associated with pharmaceutical product development, we are unable to accurately predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations. To the extent that we raise additional capital through the sale of equity or convertible debt securities, your ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect your rights as a common stockholder.

Raising additional capital may cause dilution to our stockholders, restrict our operations or require us to relinquish rights to our technologies or vidutolimod and future product candidates.

Until such time, if ever, as we can generate substantial drug revenues, we may finance our cash needs through a combination of private and public equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. We do not have any committed external source of funds. To the extent that we raise additional capital through the sale of common stock or securities convertible or exchangeable into common stock, our stockholders’ ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that materially adversely affect your rights as a common stockholder. Debt financing, if available, would increase our fixed payment obligations and may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends.

We have filed a shelf registration statement on Form S-3 with the SEC (the “Shelf Registration Statement”), pursuant to which we may offer and sell, from time to time, shares of our common stock, preferred stock, debt securities, warrants or units in an aggregate amount of up to $150 million. In connection with filing the Shelf Registration Statement, we entered into an Open Market Sale AgreementSM (the “2021 Sales Agreement”), with Jefferies LLC (“Jefferies”), pursuant to which we may offer and sell, from time to time, shares of our common stock having an aggregate offering of up to $50.0 million through an “at the market” equity offering program under which Jefferies will act as our sales agent. Future sales of securities under the Shelf Registration Statement, including under the 2021 Sales Agreement, could result in dilution of our stockholders and could have a negative impact on our stock price.

If we raise funds through additional collaborations, strategic alliances or licensing arrangements with third parties, we may have to relinquish valuable rights to our intellectual property, future revenue streams, research programs or vidutolimod and future product candidates or to grant licenses on terms that may not be favorable to us. Market volatility, the size of our public float, and competitive dynamics could also adversely impact our ability to access capital as and when needed and the terms thereof, if we can raise capital at all. If we are unable to raise adequate additional funds when needed, we may be required to delay, limit, reduce or terminate our drug development, research, or future commercialization efforts or grant rights to develop and market vidutolimod and future product candidates that we would otherwise prefer to develop and market ourselves.

46

Risks related to our business and industry

We are heavily dependent on the success of vidutolimod, our only product candidate.

We currently have no products that are approved for commercial sale and may never be able to develop marketable products. We expect that a substantial portion of our efforts and expenditures over the next several years will be devoted to our vidutolimod program, which is currently our only product candidate. Accordingly, our business currently depends heavily on the successful development, regulatory approval, and commercialization of vidutolimod. We can provide no assurance that vidutolimod will receive regulatory approval or be successfully commercialized even if we receive regulatory approval. If we were required to discontinue development of vidutolimod or if vidutolimod does not receive regulatory approval or fails to achieve significant market acceptance, we would be delayed by many years in our ability to achieve profitability, if ever.

The research, testing, manufacturing, safety, efficacy, recordkeeping, labeling, approval, licensure, sale, marketing, advertising, promotion and distribution of vidutolimod is, and will remain, subject to comprehensive regulation by the FDA and foreign regulatory authorities. Failure to obtain regulatory approval for vidutolimod in the United States, Europe, Japan, China and other major markets around the world will prevent us from commercializing and marketing vidutolimod in such jurisdictions.

Even if we were to successfully obtain approval from the FDA and foreign regulatory authorities for vidutolimod, any approval might contain significant limitations related to use, including limitations on the stage or type of cancer vidutolimod is approved to treat, as well as restrictions for specified age groups, warnings, precautions or contraindications, or requirement for a risk evaluation and mitigation strategy (“REMS”). Any such limitations or restrictions could similarly impact any supplemental marketing approvals we may obtain for vidutolimod. Furthermore, even if we obtain regulatory approval for vidutolimod, we will still need to develop a commercial infrastructure or develop relationships with collaborators to commercialize, establish a commercially viable pricing structure and obtain coverage and adequate reimbursement from third-party payors, including government healthcare programs. If we, or any future collaborators, are unable to successfully commercialize vidutolimod, we may not be able to generate sufficient revenue to continue our business.

If we fail to develop additional product candidates, our commercial opportunity could be limited.

We expect to focus the vast majority our resources on the development of vidutolimod in the near term. Part of our strategy, however, is to pursue clinical development of additional product candidates using our VLP technology. Developing, obtaining marketing approval for, and commercializing any future product candidates will require substantial additional funding and will be subject to the risks of failure inherent in drug product development. We cannot assure you that we will be able to successfully advance any future product candidates through the development process.

Even if we obtain approval from the FDA or comparable foreign regulatory authorities to market any future product candidates for any indication, we cannot assure you that any such product candidates will be successfully commercialized, widely accepted in the marketplace, or more effective than other commercially available alternatives. If we are unable to successfully develop and commercialize additional product candidates, our commercial opportunity may be limited and our business, financial condition, results of operations, stock price and prospects may be materially harmed.

We may expend our limited resources to pursue a particular product candidate or indication and fail to capitalize on product candidates or indications that may be more profitable or for which there is a greater likelihood of success.

Due to our limited financial and managerial resources, we must focus on a limited number of research programs and product candidates and on specific indications. As a result, we may forego or delay pursuit of opportunities

47

with other product candidates or for other indications that later prove to have greater commercial potential. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities. Our spending on current and future discovery and preclinical development programs and product candidates for specific indications may not yield any commercially viable products.

We will not be able to commercialize vidutolimod and future product candidates if our preclinical studies do not produce successful results and our clinical trials do not demonstrate the safety and efficacy of vidutolimod and future product candidates.

Vidutolimod and future product candidates that we may develop will require extensive preclinical and clinical trials before we can submit a marketing application to the applicable regulatory authorities. These product candidates are susceptible to the risks of failure inherent at any stage of product development, including the occurrence of unexpected or unacceptable adverse events or the failure to demonstrate efficacy in clinical trials. Clinical development is expensive and can take many years to complete, and its outcome is inherently uncertain.

The results of preclinical studies, preliminary study results, and early clinical trials of vidutolimod and future product candidates may not be predictive of the results of later-stage clinical trials or of the results of clinical trials conducted in other types of cancer or non-cancer indications. Even if early-stage clinical trials are successful, we may need to conduct additional clinical trials of our product candidates in additional patient populations or under different treatment conditions before we are able to seek regulatory approvals from the FDA or other regulatory authorities. Vidutolimod and future product candidates may not perform as we expect, and we may be unable to demonstrate to the FDA’s satisfaction that vidutolimod or any future product candidates are safe, pure, and potent, or effective for their desired indications. Moreover, while we plan to pursue a first-line therapy approval for vidutolimod, the FDA has discretion to approve our candidate for a second- or later-line indication than we seek. In addition, any negative outcomes or results for one indication or combination could delay or prevent our ability to advance development of the same candidate in a different indication or combination. Any negative outcomes or results for other TLR9 agents could potentially affect the vidutolimod development program in one or more indications or combinations. These setbacks may result in enhanced scrutiny by regulators or institutional review boards (“IRBs”) of clinical trials of product candidates, including vidutolimod, which could result in regulators or IRBs prohibiting the commencement of clinical trials, requiring additional nonclinical studies as a precondition to commencing clinical trials or imposing restrictions on the design or scope of clinical trials, as well as increasing the costs of trials or limiting the significance of the results of trials. Such setbacks could also adversely impact the desire of investigators to enroll patients in, and the desire of patients to enroll in, clinical trials of our product candidates.

Additionally, our ongoing trials are open-label studies, including our current Phase 1b, Phase 2 and Phase 2/3 trials, where both the patient and investigator know whether the patient is receiving the investigational product candidate or an existing approved drug, introducing bias in early interpretation of the results. Most typically, open-label clinical trials test only the investigational product candidate and sometimes may do so at different dose levels. Open-label clinical trials are subject to various limitations that may exaggerate any therapeutic effect as patients in open-label clinical trials are aware when they are receiving treatment. Open-label clinical trials may be subject to a “patient bias” where patients perceive their symptoms to have improved merely due to their awareness of receiving an experimental treatment. In addition, open-label clinical trials may be subject to an “investigator bias” where those assessing and reviewing the physiological outcomes of the clinical trials are aware of which patients have received treatment and may interpret the information of the treated group more favorably given this knowledge. The results from an open-label trial may not be predictive of future clinical trial results with any of our product candidates for which we include an open-label clinical trial when studied in a controlled environment with a placebo or active control.

48

We may also experience numerous unforeseen events during, or as a result of, clinical trials that could delay or prevent our ability to receive marketing approval or commercialize vidutolimod and future product candidates, including that:

• we may fail to reach an agreement with regulators or IRBs regarding the scope, design, or implementation of our clinical trials;

• the FDA, comparable foreign regulators or IRBs may not authorize us or our investigators to commence a clinical trial, to conduct a clinical trial at a prospective trial site or to amend trial protocols, or such regulators or IRBs may require that we modify or amend our clinical trial protocols in ways that make further clinical trials impractical or not financially prudent;

• we may experience delays in reaching, or fail to reach, agreement on acceptable clinical trial contracts or clinical trial protocols with prospective trial sites or contract research organizations (“CROs”);

• we may be unable to initiate or complete preclinical studies or we may experience additional enrollment delays that could prevent us from completing our clinical trials on time or at all due to the evolving impacts of the ongoing COVID-19 pandemic, and the spread of COVID-19 may affect the operations of research sites, CROs, IRBs, or key governmental agencies, such as the FDA, which may delay the development of vidutolimod or any future product candidates;

• the supply or quality of raw materials or manufactured product candidates (whether provided by us or third parties) or other materials necessary to conduct clinical trials of our product candidates may be insufficient, inadequate or not available at an acceptable cost, or in a timely manner, or we may experience interruptions in supply;

• the number of patients required for clinical trials of vidutolimod and future product candidates may be larger than we anticipate, enrollment in these clinical trials may be slower than we anticipate or participants may drop out of these clinical trials or be lost to follow-up at a higher rate than we anticipate;

• patients that enroll in our studies may misrepresent their eligibility or may otherwise not comply with the clinical trial protocol, resulting in the need to drop the patients from the study or clinical trial, increase the needed enrollment size for the clinical trial or extend its duration;

• clinical trial participants may elect to participate in alternative clinical trials sponsored by our competitors with product candidates that treat the same indications as vidutolimod and future product candidates;

• our third-party contractors may fail to comply with regulatory requirements or the clinical trial protocol, or meet their contractual obligations to us in a timely manner, or at all, and we may be required to engage in additional clinical trial site monitoring to review our contractors’ performance;

• we, regulators, or IRBs may require that we or our investigators suspend or terminate clinical trials for various reasons, including noncompliance with regulatory requirements or a finding that the participants are being exposed to unacceptable health risks, undesirable side effects, or other unexpected characteristics of the product candidate, or if such undesirable effects are found to be caused by a chemically or mechanistically similar therapeutic or therapeutic candidate;

• clinical trials of vidutolimod and future product candidates may produce negative or inconclusive results, or our studies may fail to reach the necessary level of statistical significance, and we may decide, or regulators may require us, to conduct additional clinical trials, analyses, reports, data, or preclinical trials or abandon product development programs;

• regulators may revise the requirements for approving our product candidates, or such requirements may not be as we expect or statutes, regulations clinical trial or site policies could be amended or new ones could be adopted;

49

• the cost of clinical trials of vidutolimod and future product candidates may be greater than we anticipate or we may have insufficient funds or resources to pursue or complete certain aspects of our clinical trial program or to do so within the timeframes we planned;

• we may have insufficient funds to pay the substantial user fees required by the FDA upon the submission of a BLA or equivalent authorizations from comparable foreign regulatory authorities;

• we may have delays in adding new investigators or clinical trial sites, or we may experience a withdrawal of clinical trial sites;

• there may be regulatory questions or disagreements regarding interpretations of data and results, or new information may emerge regarding vidutolimod and future product candidates;

• the FDA or comparable foreign regulatory authorities may not accept data from studies with clinical trial sites in foreign countries;

• the FDA or comparable foreign regulatory authorities may disagree with our proposed indications, fail to approve or subsequently find fault with the manufacturing processes or our manufacturing facilities for clinical and future commercial supplies, and may take longer than we anticipate to review any regulatory submissions we may make for vidutolimod or any future product candidates;

• the data collected from clinical trials of vidutolimod and future product candidates may not be sufficient for or to the satisfaction of the FDA or comparable foreign regulatory authorities to support the submission of a BLA or other comparable submission in foreign jurisdictions or to obtain regulatory approval in the United States or elsewhere;

• we may not be able to demonstrate that a product candidate provides an advantage over current standards of care or current or future competitive therapies in development; and

• regarding trials managed by our existing or any future collaborators, our collaborators may face any of the above issues, and may conduct clinical trials in ways they view as advantageous to them but potentially suboptimal for us.

In addition, ongoing disruptions caused by the COVID-19 pandemic or future pandemics may increase the likelihood that we encounter such difficulties or delays in initiating, enrolling, conducting or completing our planned and ongoing clinical trials. For example, our clinical trials that commenced in 2020 have been and continue to be adversely affected by the COVID-19 pandemic, resulting in site initiation and patient enrollment delays. As a result, in December 2021 we revised our expectations with respect to the anticipated timing of clinical data milestones in our Phase 2 clinical trial in anti-PD-1 refractory melanoma patients, our Phase 2/3 trial in first-line melanoma and our Phase 2 clinical trial in head and neck cancer. We could also encounter delays if a clinical trial is suspended or terminated by us, by the IRBs of the institutions in which such trials are being conducted, by a Data Safety Monitoring Board for such trial or by the FDA or comparable foreign regulatory authorities. A suspension or termination of a trial may be imposed due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or comparable foreign regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. In addition, changes in regulatory requirements and policies may occur, and we may need to amend clinical trial protocols to comply with these changes. Amendments may require us to resubmit our clinical trial protocols to IRBs for reexamination, which may impact the costs, timing or successful completion of a clinical trial. Further, conducting clinical trials in foreign countries, as we may do for vidutolimod or any future product candidates, presents additional risks that may delay completion of our clinical trials. These risks include the failure of enrolled patients in foreign countries to adhere to clinical protocols as a result of differences in healthcare services or cultural customs, and managing both additional administrative burdens associated with foreign regulatory schemes, and the political and economic risks relevant to such foreign countries.

50

Moreover, principal investigators for our clinical trials serve as scientific advisors or consultants to us from time to time and receive compensation in connection with such services. Under certain circumstances, we may be required to report some of these relationships to the FDA or comparable foreign regulatory authorities. The FDA or comparable foreign regulatory authority may conclude that a financial relationship between us and a principal investigator has created a conflict of interest or otherwise affected interpretation of the study. The FDA or comparable foreign regulatory authority may therefore question the integrity of the data generated at the applicable clinical trial site and the utility of the clinical trial itself may be jeopardized. This could result in a delay in approval, or rejection, of our marketing applications by the FDA or comparable foreign regulatory authority, as the case may be, and may ultimately lead to the denial of marketing approval of one or more of our product candidates. If we experience delays in testing or approvals, our development costs will also increase, and we may not have sufficient funding to complete the testing and approval process for vidutolimod and future product candidates. We will y be required to obtain additional funds to complete clinical trials and prepare for possible commercialization of vidutolimod and future product candidates. See “Risks related to our financial position and need for additional capital.” We do not know whether any preclinical tests or clinical trials beyond what we currently have anticipated or planned will be required, will begin as anticipated or planned, will need to be restructured, or will be completed on schedule, or at all. Significant delays relating to any preclinical studies or clinical trials also could shorten any periods during which we may have the exclusive right to commercialize vidutolimod and future product candidates or allow our competitors to bring products to market before we do and impair our ability to successfully commercialize vidutolimod and future product candidates and may harm our business and results of operations. In addition, many of the factors that cause, or lead to, delays in clinical trials may ultimately lead to the denial of marketing approval of vidutolimod and future product candidates. If any of these occur, our business, financial condition, results of operations, stock price and prospects may be materially harmed.

Vidutolimod is based on a novel approach to the treatment of cancer, which makes it difficult to predict the time and cost of product candidate development.

While immuno-oncology therapeutics are an emerging class of cancer treatment, they remain a novel approach. We have concentrated all of our research and development efforts on vidutolimod, and our future success depends on the successful development of this therapeutic approach. Should we encounter development problems, the FDA and foreign regulatory authorities may refuse to approve vidutolimod, or may require additional information, tests, or trials, which could significantly delay product development and significantly increase our development costs. Moreover, even if we are able to provide the requested information or clinical data to the FDA or foreign regulatory authority, there would be no guarantee that the FDA or foreign regulatory authority would accept them or approve vidutolimod. We or our CMOs may also experience delays in developing a sustainable, reproducible and scalable manufacturing process, or developing or qualifying and validating product release assays, other testing and manufacturing methods, and our or their equipment and facilities in a timely manner, which may prevent us from completing our clinical trials or commercializing vidutolimod or future product candidates on a timely or profitable basis, if at all.

In addition, the clinical trial requirements of the FDA and comparable foreign regulatory authorities and the criteria these regulators use to determine the safety and efficacy of a product candidate vary substantially according to the type, complexity, novelty and intended use and market of the potential products. The FDA and comparable foreign regulatory authorities have limited experience with the approval of oncolytic immunotherapies, which could lengthen the regulatory review process. Any product candidates that are approved may be subject to extensive post-approval regulatory requirements, including requirements pertaining to manufacturing, distribution, and promotion. We may need to devote significant time and resources to compliance with these requirements which could increase our development costs and delay or prevent commercialization of vidutolimod or any future product candidates. Further, negative clinical trial results for other immuno-oncology therapeutics may adversely impact product development and medical interest in vidutolimod, which may prevent us from completing our clinical trials, obtaining regulatory approval or commercializing vidutolimod on a timely or profitable basis, if at all.

51

Difficulty in enrolling patients has caused delays to our ongoing clinical trials of vidutolimod and could further delay ongoing trials or prevent or delay other clinical trials of vidutolimod and future product candidates. We have had difficulty enrolling patients due primarily to the COVID-19 pandemic, and may continue to find it difficult to enroll patients in our clinical trials or any subsequent trials that we may conduct.

Identifying and qualifying patients to participate in clinical studies of vidutolimod and future product candidates is critical to our success. The timing of completion of our clinical studies depends in part on the speed at which we can recruit patients to participate in testing vidutolimod and future product candidates, and we have experienced and may continue to experience delays in our clinical trials if we encounter difficulties in enrollment or due to other unforeseen factors such as the impact of the ongoing COVID-19 pandemic. For example, our clinical trials that commenced in 2020 have been adversely affected by the COVID-19 pandemic, resulting in patient enrollment delays. As a result, in December 2021, we revised our expectations with respect to the anticipated timing of clinical data milestones in our Phase 2 clinical trial in anti-PD-1 refractory melanoma patients, our Phase 2/3 trial in first-line melanoma and our Phase 2 clinical trial in head and neck cancer. Patient enrollment delays may continue, including as a result of the emergence of new COVID-19 variants, and as a result, there can be no assurance that we will be able to report trial results even on our revised anticipated timelines and it is possible such anticipated timelines may have to be adjusted further. Further, we may not be able to initiate or continue clinical trials for vidutolimod and future product candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials as required by the FDA or similar regulatory authorities outside the United States. For example, with respect to vidutolimod, we cannot be certain of the status of other competitive products in development, whether trial designs and sites for other similar products are more accessible for eligible patients or that we will be able to find enough qualified investigators and sites willing to participate in our trials. In addition, some of our competitors or potential competitors have ongoing clinical trials for product candidates that treat the same indications as vidutolimod, including product candidates that are administered by intravenous injection rather than intertumoral injection or are otherwise more convenient for patients, and patients who would otherwise be eligible for our clinical trials may instead enroll in clinical trials of our competitors’ product candidates.

The eligibility criteria of our planned clinical trials will further limit the pool of available study participants, as we will require that patients have specific characteristics that we can measure to assure their cancer is at the appropriate level to include them in a study. Additionally, the process of finding patients for our planned clinical trials may prove costly. We also may not be able to identify, recruit and enroll a sufficient number of patients to complete our clinical studies because of the perceived risks or lack of benefits of the product candidate under study, challenges with the method of administration of the product candidate, the availability and efficacy of competing therapies and clinical trials, the proximity and availability of clinical study sites for prospective patients, the patient referral practices of physicians or as a result of disruptions caused by the ongoing COVID-19 pandemic. If patients are unwilling to participate in our studies for any reason, the timeline for recruiting patients, conducting studies and obtaining regulatory approval of potential products may be delayed. Since the number of qualified clinical investigators is limited, we expect to conduct some of our clinical trials at the same clinical trial sites that some of our competitors use, which may further reduce the number of patients who are available for our clinical trials at such clinical trial sites.

The enrollment of patients further depends on many factors, including:

• the design of the clinical trial;

• our ability to recruit clinical trial investigators with the appropriate competencies and experience;

• our ability to administer vidutolimod according to the protocol dose, schedule and route of administration;

• our ability to obtain and maintain patient consents;

• reporting of the preliminary results of any of our clinical trials;

52

• the ability to monitor patients adequately during and after treatment; and

• the risk that patients enrolled in clinical trials will drop out of the clinical trials before clinical trial completion.

If we experience additional delays in the completion of, or termination of, any clinical trial of vidutolimod or any future product candidates, the commercial prospects of vidutolimod or such future product candidates will be harmed, and our ability to generate product revenue from such product candidates could be delayed or prevented.

Interim, “top-line,” and preliminary data from our clinical trials that we may announce or publish from time to time may change as more patient data become available and are subject to audit and verification procedures that could result in material changes in the final data.

From time to time, we may publicly disclose interim, top-line or preliminary data from our preclinical studies and clinical trials, based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data when we publicly disclose such data. As a result, any interim, top-line or preliminary results that we report may differ from future results of the same studies, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Preliminary or top-line data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data we previously published. As a result, interim, top-line and preliminary data should be viewed with caution until the final data are available. In addition, preliminary or interim data from ongoing clinical trials are subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available or as patients from our clinical trials continue other treatments for their disease. Adverse differences between any preliminary or interim data we disclose and final data could significantly harm our business prospects.

Further, others, including regulatory agencies, may not accept or agree with our assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular program, the approvability or commercialization of the particular product candidate or product and our company in general. In addition, the information we choose to publicly disclose regarding a particular study or clinical trial is based on what is typically extensive information, and you or others may not agree with what we determine is material or otherwise appropriate information to include in our disclosure. Any information we determine not to disclose may ultimately be deemed significant by you or others with respect to future decisions, conclusions, views, activities or otherwise regarding a particular product candidate or our business. If the interim, top-line or preliminary data that we report differ from final results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, product candidates may be harmed, which could significantly harm our business, financial condition, results of operations and prospects.

Vidutolimod is being, and future product candidates may be, evaluated in combination with third-party drugs, and we will have limited or no control over the supply, regulatory status, or regulatory approval of such drugs.

Vidutolimod is being, and future product candidates may be, evaluated in combination with checkpoint inhibitors (“CPIs”) or other compounds. In December 2020, we entered into a clinical collaboration with BMS to evaluate vidutolimod in combination with nivolumab and in May 2021, we entered into a supply agreement with Regeneron to evaluate vidutolimod concurrently or in combination with cemiplimab. Our ability to develop and ultimately commercialize vidutolimod and future product candidates used in combination with avelumab, nivolumab, cemiplimab, pembrolizumab, atezolizumab, ipilimumab or any other CPIs or other compounds will depend on our ability to access such drugs on commercially reasonable terms for the clinical trials and their

53

availability for use with the commercialized product, if approved. We cannot be certain that current or potential future commercial relationships will provide us with a steady supply of such drugs on commercially reasonable terms or at all.

Any failure to maintain or enter into new successful commercial relationships, or inability to source or purchase CPIs or other potential combination agents in the market, may delay our development timelines, increase our costs and jeopardize our ability to develop vidutolimod and future product candidates as potential combination therapies, which may materially harm our business, financial condition, results of operations, stock price and prospects.

Moreover, the development of product candidates for use in combination with another product or product candidate may present challenges that are not encountered when developing single-agent product candidates. For example, the FDA may require us to use more complex clinical trial designs in order to evaluate the contribution of each product and product candidate to any observed effects. During an end-of-Phase 1 meeting held in March 2020 to discuss the planned registration path for vidutolimod in melanoma, the FDA indicated that one single-arm Phase 2 trial may not be sufficient to support accelerated approval of a BLA for vidutolimod for the treatment of anti-PD-1 failure patients with metastatic or unresectable melanoma in combination with pembrolizumab. The FDA also recommended that we conduct a randomized trial in the proposed patient population to evaluate the contribution of each component to the potential treatment effect of the combination. Additionally, following product approval, the FDA may require that products used in conjunction with each other be cross labeled for combined use. To the extent that we do not have rights to the other product, this may require us to work with a third party under terms unfavorable to us to satisfy such a requirement. Moreover, developments related to the other product may impact our clinical trials for the combination as well as our commercial prospects should we receive marketing approval. Such developments may include changes to the other product’s safety or efficacy profile, changes to the availability of the approved product, and changes to the standard of care.

In the event that BMS, Regeneron or any future collaborator or supplier cannot continue to supply their products on commercially reasonable terms, we would need to identify alternatives for accessing such CPIs. Additionally, should the supply of products from BMS, Regeneron or any future collaborator or supplier be interrupted, delayed or otherwise be unavailable to us or our collaborators, our clinical collaborations may be delayed. In the event we are unable to source an alternative supply, or are unable to do so on commercially reasonable terms, our business, financial condition, results of operations, stock price and prospects may be materially harmed.

Changes in product candidate manufacturing or formulation may result in additional costs or delay.

As product candidates are developed through preclinical studies to later-stage clinical trials towards approval and commercialization, it is common that various aspects of the development program, such as manufacturing methods and formulation, are altered along the way in an effort to optimize processes and results. Any of these changes could cause vidutolimod or any future product candidates to perform differently and affect the results of planned clinical trials or other future clinical trials conducted with the altered materials. Such changes may also require additional testing, or notification to, or approval by, the FDA or a comparable foreign regulatory authority. This could delay completion of clinical trials, require the conduct of bridging clinical trials or studies, require the repetition of one or more clinical trials, increase clinical trial costs, delay approval of vidutolimod and future product candidates and jeopardize our ability to commence product sales and generate revenue.

54

If we are unable to successfully commercialize vidutolimod or any product candidate for which we receive regulatory approval, or experience significant delays in doing so, our business will be materially harmed.

If we are successful in obtaining marketing approval from applicable regulatory authorities for vidutolimod or any future product candidates, our ability to generate revenues from vidutolimod or any future product candidates will depend on our success in:

• launching commercial sales of vidutolimod and future product candidates, whether alone or in collaboration with others;

• receiving an approved label with claims that are necessary or desirable for successful marketing, and that does not contain safety or other limitations that would impede our ability to market vidutolimod or any future product candidates;

• creating market demand for our product candidates through marketing, sales and promotion activities;

• hiring, training, and deploying a sales force or contracting with third parties to commercialize vidutolimod or any future product candidates in the United States;

• manufacturing, either on our own or through third parties, product candidates in sufficient quantities and at acceptable quality and cost to meet commercial demand at launch and thereafter;

• establishing and maintaining agreements with wholesalers, distributors, and group purchasing organizations on commercially reasonable terms;

• creating partnerships with, or offering licenses to, third parties to promote and sell product candidates in foreign markets where we receive marketing approval;

• maintaining patent and trade secret protection and regulatory exclusivity for vidutolimod or any future product candidates;

• achieving market acceptance of vidutolimod or any future product candidates by patients, the medical community, and third-party payors;

• achieving appropriate reimbursement for vidutolimod or any future product candidates;

• effectively competing with other therapies; and

• maintaining an acceptable tolerability profile of vidutolimod or any future product candidates following launch.

To the extent we are not able to do any of the foregoing, our business, financial condition, results of operations, stock price and prospects will be materially harmed.

We face significant competition from other biopharmaceutical and biotechnology companies, academic institutions, government agencies, and other research organizations, which may result in others discovering, developing or commercializing products more quickly or marketing them more successfully than us. If their product candidates are shown to be safer or more effective than ours, our commercial opportunity may be reduced or eliminated.

The development and commercialization of cancer immunotherapy products is characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary rights. We face competition with respect to vidutolimod, and will face competition with respect to any product candidates that we may seek to develop or commercialize in the future, from major biopharmaceutical companies, specialty biopharmaceutical companies, and biotechnology companies worldwide. There are a number of large biopharmaceutical and biotechnology companies that currently market and sell products or are pursuing the development of products for the treatment of solid tumors, including oncolytic immunotherapy and cancer vaccine approaches. Additionally, certain companies whom we view as our most direct potential competitors are currently developing in cancer

55

immunotherapy that may have utility for similar indications that we are targeting, as well as competing therapies utilizing LAG-3 and other approaches. Potential competitors also include academic institutions, government agencies, and other public and private research organizations that conduct research, seek patent protection, and establish collaborative arrangements for research, development, manufacturing, and commercialization.

While vidutolimod is intended to be used in combination with other drugs with different mechanisms of action, if and when marketed it will still compete with a number of drugs that are currently marketed or in development that also target cancer. To compete effectively with these drugs, vidutolimod or any future product candidates will need to demonstrate advantages in clinical efficacy and safety compared to these competitors when used alone or in combination with other drugs.

Our commercial opportunities could be reduced or eliminated if our competitors develop and commercialize products that are safer, more effective, have fewer or less severe side effects, are easier to administer or are less expensive alone or in combination with other therapies than any products that we may develop alone or in combination with other therapies. Our competitors also may obtain the FDA’s or comparable foreign regulatory authorities’ approval for their products more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market. In addition, our ability to compete may be affected in many cases by insurers or other third-party payors coverage decisions.

Many of the companies with which we are competing or may compete in the future have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals, and marketing approved products than we do. Mergers and acquisitions in the biopharmaceutical and biotechnology industries may result in even more resources being concentrated among a smaller number of our competitors. Early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These third parties compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in developing or acquiring technologies complementary to, or necessary for, our programs. If we are unable to successfully compete with these companies our business, financial condition, results of operations, stock price and prospects may be materially harmed.

If we are unable to establish effective marketing, sales and distribution capabilities or enter into agreements with third parties to market and sell vidutolimod or any future product candidates, if they are approved, the revenues that we generate may be limited and we may never become profitable.

We currently do not have a commercial infrastructure for the marketing, sale, and distribution of our cancer immunotherapies. If vidutolimod or any future product candidates receive marketing approval, we intend to commercialize such product candidates on our own in the United States and potentially with pharmaceutical or biotechnology partners in other geographies. In order to commercialize our products, we must build our marketing, sales, and distribution capabilities or make arrangements with third parties to perform these services. We may not be successful in doing so. Should we decide to move forward in developing our own marketing capabilities, we may incur expenses prior to product launch or even approval in order to recruit a sales force and develop a marketing and sales infrastructure. If a commercial launch is delayed as a result of the FDA’s or comparable foreign regulatory authority’s requirements or for other reasons, we would incur these expenses prior to being able to realize any revenue from sales of vidutolimod and future product candidates. Even if we are able to effectively hire a sales force and develop a marketing and sales infrastructure, our sales force and marketing teams may not be successful in commercializing vidutolimod or any future product candidates. This may be costly, and our investment would be lost if we cannot retain or reposition our sales and marketing personnel.

We may also or alternatively decide to collaborate with third-party marketing and sales organizations to commercialize any approved product candidates in the United States, in which event, our ability to generate product revenues may be limited. To the extent we rely on third parties to commercialize any products for which

56

we obtain regulatory approval, we may receive less revenues than if we commercialized these products ourselves, which could materially harm our prospects. In addition, we would have less control over the sales efforts of any other third parties involved in our commercialization efforts, and could be held liable if they failed to comply with applicable legal or regulatory requirements.

We have no prior experience in the marketing, sale, and distribution of biopharmaceutical products, and there are significant risks involved in building and managing a commercial infrastructure. The establishment and development of commercial capabilities, including compliance plans, to market any products we may develop will be expensive and time consuming and could delay any product launch, and we may not be able to successfully develop this capability. We will have to compete with other biopharmaceutical and biotechnology companies, including oncology-focused companies, to recruit, hire, train, manage, and retain marketing and sales personnel, which is expensive and time consuming and could delay any product launch. Developing our sales capabilities may also divert resources and management attention away from product development. In the event we are unable to develop a marketing and sales infrastructure, we may not be able to commercialize vidutolimod or any future product candidates in the United States or elsewhere, which could limit our ability to generate product revenues and materially harm our business, financial condition, results of operations, stock price and prospects. Factors that may inhibit our efforts to commercialize vidutolimod or any future product candidates include:

• the inability to recruit, train, manage, and retain adequate numbers of effective sales and marketing personnel;

• the inability of sales personnel to obtain access to physicians or persuade adequate numbers of physicians to prescribe vidutolimod or any future product candidates;

• our inability to effectively oversee a geographically dispersed sales and marketing team;

• the costs associated with training sales and marketing personnel on legal and regulatory compliance matters and monitoring their actions;

• an inability to secure adequate coverage and reimbursement by government and private health plans;

• the clinical indications for which the products are approved and the claims that we may make for the products;

• limitations or warnings, including distribution or use restrictions, contained in the product’s approved labeling;

• any distribution and use restrictions imposed by the FDA or comparable foreign regulatory authorities or to which we agree as part of a mandatory REMS or voluntary risk management plan;

• liability for sales or marketing personnel who fail to comply with the applicable legal and regulatory requirements;

• the lack of complementary products to be offered by sales personnel, which may put us at a competitive disadvantage relative to companies with more extensive product lines; and

• unforeseen costs and expenses associated with creating an independent sales and marketing organization or engaging a contract sales organization.

If vidutolimod or any future product candidates do not achieve broad market acceptance, the revenues that we generate from their sales may be limited, and we may never become profitable.

We have never commercialized a product candidate for any indication. Even if vidutolimod and future product candidates are approved by the appropriate regulatory authorities for marketing and sale, they may not gain acceptance among physicians, patients, third-party payors, and others in the medical community. If any product candidates for which we obtain regulatory approval do not gain an adequate level of market acceptance, we could

57

be prevented from or significantly delayed in achieving profitability. Market acceptance of vidutolimod and future product candidates by the medical community, patients, and third-party payors will depend on a number of factors, some of which are beyond our control. For example, physicians are often reluctant to switch their patients and patients may be reluctant to switch from existing therapies even when new and potentially more effective or safer treatments enter the market.

Efforts to educate the medical community and third-party payors on the benefits of vidutolimod and our novel approach to cancer treatment, and future product candidates, may require significant resources and may not be successful. If vidutolimod or any future product candidates are approved but do not achieve an adequate level of market acceptance, we could be prevented from or significantly delayed in achieving profitability. The degree of market acceptance of vidutolimod and future product candidates will depend on a number of factors, including:

• the efficacy of our vidutolimod and our VLP modality, and future product candidates alone or in combination with checkpoint inhibitor immunotherapies or other therapies;

• the commercial success of the checkpoint blockade drugs with which vidutolimod or future products are or may be co-administered;

• the prevalence and severity of adverse events associated with vidutolimod and future product candidates or those products with which they are co-administered;

• the clinical indications for which the products are approved and the approved claims that we may make for the products;

• limitations or warnings contained in the product’s FDA-approved labeling or those of comparable foreign regulatory authorities, including potential limitations or warnings for vidutolimod and future product candidates that may be more restrictive than other competitive products;

• changes in the standard of care for the targeted indications for vidutolimod and future product candidates, which could reduce the marketing impact of any claims that we could make following FDA approval or approval by comparable foreign regulatory authorities, if obtained;

• the relative convenience and ease of administration of vidutolimod and future product candidates and any products with which they are co-administered;

• the cost of treatment compared with the economic and clinical benefit of alternative treatments or therapies;

• the availability of adequate coverage or reimbursement by third parties, such as insurance companies and other healthcare payors, and by government healthcare programs, including Medicare and Medicaid;

• the price concessions required by third-party payors to obtain coverage;

• the extent and strength of our marketing and distribution of vidutolimod and future product candidates;

• the safety, efficacy, and other potential advantages over, and availability of, alternative treatments already used or that may later be approved;

• distribution and use restrictions imposed by the FDA or comparable foreign regulatory authorities with respect to vidutolimod and future product candidates or to which we agree as part of a REMS or voluntary risk management plan;

• the timing of market introduction of vidutolimod and future product candidates, as well as competitive products;

• our ability to offer vidutolimod and future product candidates for sale at competitive prices;

• the willingness of the target patient population to try new therapies and of physicians to prescribe these therapies;

58

• the extent and strength of our third-party manufacturer and supplier support;

• the actions of companies that market any products with which vidutolimod and future product candidates are co-administered;

• the approval of other new products;

• adverse publicity about vidutolimod and future product candidates or any products with which they are co-administered, or favorable publicity about competitive products; and

• potential product liability claims.

The size of the potential markets for vidutolimod or any future product candidates is difficult to estimate and, if any of our assumptions are inaccurate, the actual markets for vidutolimod or any future product candidates may be smaller than our estimates.

The potential market opportunities for vidutolimod or any future product candidates are difficult to estimate and will depend in large part on the drugs with which vidutolimod or any future product candidates are co-administered and the success of competing therapies and therapeutic approaches. Our estimates of the potential market opportunities in melanoma, HNSCC, CSCC, MCC and other indications are predicated on many assumptions, which may include industry knowledge and publications, third-party research reports, and other surveys. Although we believe that our internal assumptions are reasonable, these assumptions involve the exercise of significant judgment on the part of our management, are inherently uncertain, and their reasonableness has not been assessed by an independent source. If any of the assumptions proves to be inaccurate, the actual markets and patient populations eligible for vidutolimod and future product candidates could be smaller than our estimates of the potential market opportunities.

Negative developments in the field of immuno-oncology could damage public perception of vidutolimod or any future product candidates and negatively affect our business.

The commercial success of vidutolimod or any future product candidates will depend in part on public acceptance of the use of cancer immunotherapies. Adverse events in clinical trials of vidutolimod or any future product candidates or adverse outcomes, including actual or perceived lack of efficacy, or adverse events in clinical trials of others developing similar products and the resulting publicity, as well as any other negative developments in the field of immuno-oncology that may occur in the future, including in connection with competitor therapies, could result in a decrease in demand for vidutolimod or any future product candidates that we may develop. These events could also result in the suspension, discontinuation, or clinical hold of or modification to our clinical trials. If public perception is influenced by claims that the use of cancer immunotherapies is unsafe, whether related to our therapies or those of our competitors, vidutolimod and future product candidates may not be accepted by the general public or the medical community and potential clinical trial subjects may be discouraged from enrolling in our clinical trials. As a result, we may not be able to continue or may be delayed in conducting our development programs. Future negative developments in the field of immuno-oncology or the biopharmaceutical industry could also result in greater governmental regulation, stricter labeling requirements and potential regulatory delays in the testing or approvals of vidutolimod or any future product candidates. Any increased scrutiny could delay or increase the costs of obtaining marketing approval for vidutolimod or any future product candidates.

Product liability lawsuits against us could cause us to incur substantial liabilities and could limit commercialization of vidutolimod and future product candidates that we may develop.

We will face an inherent risk of product liability exposure related to the testing of vidutolimod and future product candidates in human clinical trials and will face an even greater risk if we commercially sell vidutolimod or any future product candidates that we may develop. If we cannot successfully defend ourselves against claims that

59

vidutolimod and future product candidates caused injuries, we could incur substantial liabilities. Regardless of merit or eventual outcome, liability claims may result in:

• decreased demand for any of vidutolimod and future product candidates that we may develop;

• injury to our reputation and significant negative media attention;

• regulatory investigations that could require costly recalls or product modifications;

• withdrawal of clinical trial participants;

• significant costs to defend the related litigation;

• substantial monetary awards to trial participants or patients;

• loss of revenue;

• the diversion of management’s attention away from managing our business; and

• the inability to commercialize vidutolimod and future product candidates that we may develop.

Although we maintain product liability insurance coverage, it may not be adequate to cover all liabilities that we may incur. We anticipate that we will need to increase our insurance coverage when we begin clinical trials and if we successfully commercialize any product candidate. Insurance coverage is increasingly expensive. We may not be able to maintain product liability insurance coverage at a reasonable cost or in an amount adequate to satisfy any liability that may arise.

Even if we are able to commercialize vidutolimod or any future product candidates, such drugs may become subject to unfavorable pricing regulations or third-party coverage and reimbursement policies, which would harm our business.

The regulations that govern regulatory approvals, pricing and reimbursement for new drugs vary widely from country to country. Some countries require approval of the sale price of a drug before it can be marketed. In many countries, the pricing review period begins after marketing approval is granted. In some foreign markets, prescription pharmaceutical pricing remains subject to continuing governmental control even after initial approval is granted. As a result, we might obtain marketing approval for a product candidate in a particular country, but then be subject to price regulations that delay our commercial launch of the product candidate, possibly for lengthy time periods, and negatively impact the revenues we are able to generate from the sale of the product candidate in that country. Adverse pricing limitations may hinder our ability to recoup our investment in vidutolimod or any future product candidates, even if vidutolimod and future product candidates obtain marketing approval.

Our ability to commercialize vidutolimod and future product candidates successfully also will depend in part on the extent to which coverage and reimbursement for vidutolimod and future product candidates and related treatments will be available from third-party payors. In the United States and markets in other countries, patients generally rely on third-party payors to reimburse all or part of the costs associated with their treatment. Adequate coverage and reimbursement from governmental healthcare programs, such as Medicare and Medicaid, and commercial payors is critical to new product acceptance. Our ability to successfully commercialize our product candidates will depend in part on the extent to which coverage and adequate reimbursement for these products and related treatments will be available from government health administration authorities, private health insurers and other organizations. Government authorities and other third-party payors, such as private health insurers and health maintenance organizations, decide which medications they will pay for and establish reimbursement levels. In the United States, the principal decisions about reimbursement for new medicines are typically made by the Centers for Medicare & Medicaid Services, or CMS, an agency within the U.S. Department of Health and Human Services. CMS decides whether and to what extent a new medicine will be

60

covered and reimbursed under Medicare and private payors tend to follow CMS to a substantial degree. Factors payors consider in determining reimbursement are based on whether the product is:

• a covered benefit under its health plan;

• safe, effective and medically necessary;

• appropriate for the specific patient;

• cost-effective; and

• neither experimental nor investigational.

A primary trend in the U.S. healthcare industry and elsewhere is cost containment. Government authorities and other third-party payors have attempted to control costs by limiting coverage and the amount of reimbursement for particular drugs. Increasingly, third-party payors are requiring that drug companies provide them with predetermined discounts from list prices and are challenging the prices charged for drugs. For products administered under the supervision of a physician, such as vidutolimod, obtaining coverage and adequate reimbursement may be particularly difficult because of the higher prices often associated with such drugs. We cannot be sure that coverage will be available for any product candidate that we commercialize and, if coverage is available, the level of reimbursement. Reimbursement may impact the demand for, or the price of, any product candidate for which we obtain marketing approval. If reimbursement is not available or is available only to limited levels, we may not be able to successfully commercialize any product candidate for which we obtain marketing approval.

There may be significant delays in obtaining reimbursement for newly approved drugs, and coverage may be more limited than the purposes for which the drug is approved by the FDA or similar regulatory authorities outside the United States. Moreover, eligibility for reimbursement does not imply that any drug will be paid for in all cases or at a rate that covers our costs, including research, development, manufacturing, sale and distribution. Interim reimbursement levels for new drugs, if applicable, may also not be sufficient to cover our costs and may not be made permanent. Reimbursement rates may vary according to the use of the drug and the clinical setting in which it is used, may be based on reimbursement levels already set for lower cost drugs and may be incorporated into existing payments for other services. Net prices for drugs may be reduced by mandatory discounts or rebates required by government healthcare programs or private payors and by any future relaxation of laws that presently restrict imports of drugs from countries where they may be sold at lower prices than in the United States. In addition, many pharmaceutical manufacturers must calculate and report certain price reporting metrics to the government, such as average sales price, or ASP, and best price. Penalties may apply in some cases when such metrics are not submitted accurately and timely. Further, these prices for drugs may be reduced by mandatory discounts or rebates required by government healthcare programs. Our inability to promptly obtain coverage and profitable payment rates from both government-funded and private payors for any approved drugs that we develop could have a material adverse effect on our operating results, our ability to raise capital needed to commercialize drugs and our overall financial condition.

Risks related to COVID-19 or other public health crises

A pandemic, epidemic, or outbreak of an infectious disease, such as the ongoing COVID-19 pandemic, has and may in the future materially and adversely affect our business, including our preclinical studies, clinical trials, third parties on whom we rely, our supply chain, our ability to raise capital and our financial results.

We are subject to risks related to public health crises such as the ongoing COVID-19 pandemic. The pandemic and government measures taken in response have also had a significant impact, both direct and indirect, on businesses and commerce, as worker shortages have occurred, supply chains have been disrupted, facilities and production have been suspended, and demand for certain goods and services, such as medical services and supplies, has spiked, while demand for other goods and services, such as travel, has fallen. The extent to which the COVID-19 pandemic, or ongoing measures in response to the pandemic, may further impact our preclinical

61

studies or clinical trial operations, as well as our supply chain, will depend on future developments, which are highly uncertain and cannot be predicted with confidence, such as the duration of the pandemic, the severity and spread of new strains or variants of the virus, such as the Delta and Omicron variants, the pace and success of vaccination and booster efforts and the effectiveness of existing or future vaccine or the effectiveness of other actions to contain and treat COVID-19 or its variants. The ongoing COVID-19 pandemic may also affect or continue to affect employees of third-party contract research organizations (“CROs”) located in affected geographies that we rely upon to carry out our clinical trials. For example, our clinical trials that commenced in 2020 have been, and continue to be, adversely affected by the COVID-19 pandemic as a result of delays in enrolling patients. As a result, in December 2021, we revised our expectations with respect to the anticipated timing of clinical data milestones in our Phase 2 clinical trial in anti-PD-1 refractory melanoma patients, our Phase 2/3 trial in first-line melanoma and our Phase 2 clinical trial in head and neck cancer. As COVID-19 or its variants continue to spread, despite current vaccination efforts, around the globe, we may experience additional disruptions that could severely impact our business and clinical trials, including:

• further delays or difficulties in enrolling patients in our clinical trials

• delays or difficulties in clinical site initiation, including difficulties in recruiting clinical site investigators and clinical site staff;

• diversion of healthcare resources away from the conduct of clinical trials, including the diversion of hospitals serving as our clinical trial sites and hospital staff supporting the conduct of our clinical trials or absenteeism due to the ongoing COVID-19 pandemic that reduces site resources;

• interruption of key clinical trial activities, such as clinical trial site monitoring, due to limitations on travel imposed or recommended by federal or state governments, employers and others or interruption of clinical trial subject visits and study procedures, the occurrence of which could affect the integrity of clinical trial data;

• risk that participants enrolled in our clinical trials will contract COVID-19 or variants thereof while the clinical trial is ongoing, which could impact the results of the clinical trial, including by increasing the number of observed adverse events or patient withdrawals from our trials;

• limitations in employee resources that would otherwise be focused on conducting our clinical trials, including because of sickness of employees or their families or the desire of employees to avoid contact with large groups of people;

• delays in receiving authorizations from local regulatory authorities to initiate our planned clinical trials;

• delays in clinical sites receiving the supplies and materials needed to conduct our clinical trials;

• interruption in global shipping that may affect the transport of clinical trial materials, such as investigational drug product used in our clinical trials;

• changes in local regulations as part of a response to the ongoing COVID-19 pandemic, which may require us to change the ways in which our clinical trials are conducted, which may result in unexpected costs, or to discontinue the clinical trials altogether;

• interruptions or delays in preclinical studies due to restricted or limited operations at research and development laboratory facilities;

• delays in necessary interactions with local regulators, ethics committees and other important agencies and contractors due to limitations in employee resources or forced furlough of government employees; and

• refusal of the FDA to accept data from clinical trials in affected geographies outside the United States.

Any additional future negative impact the evolving COVID-19 pandemic has on patient enrollment or treatment or the development of vidutolimod and future product candidates could cause additional, and potentially costly

62

delays to clinical trial activities, which could adversely affect our ability to obtain regulatory approval for and to commercialize vidutolimod and future product candidates, if approved, increase our operating expenses, and have a material adverse effect on our financial results. Since the beginning of the COVID-19 pandemic, three vaccines for COVID-19 have received Emergency Use Authorization by the FDA and one of those later received marketing approval. Additional vaccines may be authorized or approved in the future. The continued demand for vaccines as the need for boosters persists and potential for manufacturing facilities and materials to be commandeered under the Defense Production Act of 1950, or equivalent foreign legislation, may make it more difficult to obtain materials or manufacturing slots for the products needed for our clinical trials, which could lead to delays in these trials. The COVID-19 pandemic has also caused significant disruptions to the U.S. and global economies. This increased volatility and economic dislocation may make it more difficult for us to raise capital on favorable terms, or at all.

Although we have experienced impacts of the ongoing COVID-19 pandemic on our business and operations, we cannot currently predict the scope and severity of any additional impacts. If we or any of the third parties with whom we engage were to experience additional shutdowns or other business disruptions, our ability to conduct our business in the manner and on the timelines presently planned could be materially and negatively affected, which could have a material adverse impact on our business and our results of operations and financial condition. To the extent the COVID-19 pandemic adversely affects our business and financial results, it may also heighten many of the other risks described in this “Risk Factors” section, such as those relating to the timing and completion of our clinical trials and our ability to obtain future financing.

Risks related to government regulation

Even if our development efforts are successful, we may not obtain regulatory approval of vidutolimod or any future product candidates in the United States or other jurisdictions, which would prevent us from commercializing vidutolimod and future product candidates. Even if we obtain regulatory approval for vidutolimod and future product candidates, any such approval may be subject to limitations, including with respect to the approved indications or patient populations, which could impair our ability to successfully commercialize vidutolimod or any future product candidates.

We are not permitted to market or promote or sell vidutolimod or any future product candidates before we receive regulatory approval from the FDA or comparable foreign regulatory authorities, and we may never receive such regulatory approval. Securing marketing approval requires the submission of extensive preclinical and clinical data and supporting information to regulatory authorities for each therapeutic indication to establish the product candidate’s safety and efficacy for that indication. Securing marketing approval also requires the submission of information about the product manufacturing process to, and inspection of manufacturing facilities and clinical trial sites by, the regulatory authorities. If we do not receive approval from the FDA and comparable foreign regulatory authorities for any of vidutolimod and future product candidates, we will not be able to commercialize such product candidates in the United States or in other jurisdictions. If significant delays in obtaining approval for and commercializing vidutolimod and future product candidates occur in any jurisdictions, our business, financial condition, results of operations, stock price and prospects will be materially harmed. Even if vidutolimod and future product candidates are approved, they may:

• be subject to limitations on the indicated uses or patient populations for which they may be marketed, distribution restrictions, or other conditions of approval;

• contain significant safety warnings, including boxed warnings, contraindications, and precautions;

• not be approved with label statements necessary or desirable for successful commercialization; or

• contain requirements for costly post-market testing and surveillance, or other requirements, including the submission of a REMS to monitor the safety or efficacy of the products.

We have not previously submitted a BLA to the FDA, or a similar marketing application to comparable foreign regulatory authorities, for vidutolimod or any product candidate, and we can provide no assurance that we will

63

ultimately be successful in obtaining regulatory approval for claims that are necessary or desirable for successful marketing, if at all.

The regulatory approval processes of the FDA and comparable foreign regulatory authorities are lengthy, time consuming and inherently unpredictable. If we are not able to obtain, or experience delays in obtaining, required regulatory approvals, we will not be able to commercialize vidutolimod and future product candidates as expected, and our ability to generate revenue may be materially impaired.

The time required to obtain approval by the FDA and comparable foreign regulatory authorities is unpredictable but typically takes many years following the commencement of clinical trials and depends upon numerous factors, including the substantial discretion of the regulatory authorities. In addition, approval policies, regulations, or the type and amount of clinical data necessary to gain approval may change during the course of a product candidate’s clinical development and may vary among jurisdictions. These regulatory requirements may require us to amend our clinical trial protocols, conduct additional preclinical studies or clinical trials that may require regulatory or IRB approval, or otherwise cause delays in obtaining approval or rejection of an application. Any delay in obtaining or failure to obtain required approvals could materially adversely affect our ability to generate revenue from the particular product candidate, which may materially harm our business, financial condition, results of operations, stock price and prospects.

Regulatory authorities have substantial discretion in the approval process and may refuse to accept any application or may decide that our data are insufficient for approval and require additional preclinical, clinical or other studies. In addition, varying interpretations of the data obtained from preclinical and clinical testing could delay, limit or prevent marketing approval of a product candidate. The number and types of preclinical studies and clinical trials that will be required for regulatory approval also varies depending on the product candidate, the disease or condition that the product candidate is designed to address, and the regulations applicable to any particular product candidate. Approval policies, regulations or the type and amount of clinical data necessary to gain approval may change during the course of a product candidate’s clinical development and may vary among jurisdictions, and there may be varying interpretations of data obtained from preclinical studies or clinical trials, any of which may cause delays or limitations in the approval or a decision not to approve an application. It is possible that vidutolimod and future product candidates will never obtain the appropriate regulatory approvals necessary for us to commence product sales.

If we experience delays in obtaining approval, if we fail to obtain approval of vidutolimod or any future product candidate or if the label for a product candidate does not include the labeling claims necessary or desirable for the successful commercialization of that product candidate, the commercial prospects for such product candidate may be harmed and our ability to generate revenues from that product candidate may be materially impaired.

Vidutolimod or future product candidates may cause undesirable side effects or have other properties that could delay or prevent their regulatory approval, limit the commercial profile of an approved label, or result in significant negative consequences following marketing approval, if any. Serious adverse events or undesirable side effects caused by vidutolimod and future product candidates could cause us, IRBs, and other reviewing entities or regulatory authorities to interrupt, delay, or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA or comparable foreign regulatory authorities. For example, if concerns are raised regarding the safety of a new therapeutic as a result of undesirable side effects identified during clinical or preclinical testing, the FDA or comparable foreign regulatory authority may order us to cease further development, decline to approve the product candidate or issue a letter requesting additional data or information prior to making a final decision regarding whether or not to approve the product candidate. The FDA or comparable foreign regulatory authorities, or IRBs and other reviewing entities, may also require, or we may voluntarily develop, strategies for managing adverse events during clinical development, which could include restrictions on our enrollment criteria, the use of stopping criteria, adjustments to a study’s design, or the monitoring of safety data by a data monitoring committee, among other strategies. For example, patients enrolled in our ongoing clinical trials of vidutolimod have experienced mild to moderate adverse events, consisting

64

mainly of flu-like symptoms and injection site reactions. In response to these adverse events, we have implemented prophylactic measures, including intravenous fluids, antiemetics, and antipryetics. The FDA’s or a comparable foreign regulatory authority’s requests for additional data or information could also result in substantial delays in the approval of vidutolimod and future product candidates.

Further, clinical trials by their nature utilize a sample of the potential patient population. With a limited number of patients and limited duration of exposure, rare and severe side effects of a product candidate may only be uncovered when a significantly larger number of patients are exposed to the product candidate or when patients are exposed for a longer period of time.

Undesirable side effects caused by vidutolimod or any future product candidates could also result in denial of regulatory approval by the FDA or comparable foreign regulatory authorities for any or all targeted indications or the inclusion of unfavorable information in our product labeling, such as limitations on the indicated uses for which the products may be marketed or distributed, a label with significant safety warnings, including boxed warnings, contraindications, and precautions, a label without statements necessary or desirable for successful commercialization, or may result in requirements for costly post-marketing testing and surveillance, or other requirements, including REMS, to monitor the safety or efficacy of the products, and in turn prevent us from commercializing and generating revenues from the sale of vidutolimod and future product candidates. Any such limitations or restrictions could similarly impact any supplemental marketing approvals we may obtain for vidutolimod. Undesirable side effects may limit the potential market for any approved products or could result in restrictions on manufacturing processes, the discontinuation of the sales and marketing of the product, or withdrawal of product approvals. We could also be sued and held liable for harm caused to patients, or become subject to fines, injunctions or the imposition of civil or criminal penalties.

If vidutolimod and future product candidates are associated with serious adverse events or undesirable side effects or have properties that are unexpected, we may need to abandon development or limit development of that product candidate to certain uses or subpopulations in which the undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective. The therapeutic-related side effects could affect patient recruitment or the ability of enrolled patients to complete the trial or result in potential product liability claims. Any of these occurrences may materially harm our business, financial condition, results of operations, stock price and prospects.

Regulatory approval by the FDA or comparable foreign regulatory authorities is limited to those specific indications and conditions for which approval has been granted, and we may be subject to substantial fines, criminal penalties, injunctions, or other enforcement actions if we are determined to be promoting the use of our products for unapproved or “off-label” uses, or in a manner inconsistent with the approved labeling, resulting in damage to our reputation and business.

We must comply with requirements concerning advertising and promotion for any product candidates for which we obtain marketing approval. Promotional communications with respect to therapeutics are subject to a variety of legal and regulatory restrictions and continuing review by the FDA, Department of Justice, Department of Health and Human Services’ Office of Inspector General, state attorneys general, members of Congress, and the public. When the FDA or comparable foreign regulatory authorities issue regulatory approval for a product candidate, the regulatory approval is limited to those specific uses and indications for which a product is approved. If we are not able to obtain FDA approval for desired uses or indications for vidutolimod and future product candidates, we may not market or promote them for those indications and uses, referred to as off-label uses, and our business, financial condition, results of operations, stock price and prospects will be materially harmed. We also must sufficiently substantiate any claims that we make for any products, including claims comparing those products to other companies’ products, and must abide by the FDA’s strict requirements regarding the content of promotion and advertising.

Physicians may choose to prescribe products for uses that are not described in the product’s labeling and for uses that differ from those tested in clinical trials and approved by the regulatory authorities. Regulatory authorities in

65

the United States generally do not restrict or regulate the behavior of physicians in their choice of treatment within the practice of medicine. Regulatory authorities do, however, restrict communications by biopharmaceutical companies and third parties acting on behalf of such companies concerning off-label use.

If we are found to have impermissibly promoted any of vidutolimod and future product candidates, we may become subject to significant liability and government fines. The FDA and other agencies actively enforce the laws and regulations regarding product promotion, particularly those prohibiting the promotion of off-label uses, and a company that is found to have improperly promoted a product may be subject to significant sanctions. The federal government has levied large civil and criminal fines against companies for alleged improper promotion and has enjoined several companies from engaging in off-label promotion. The FDA has also requested that companies enter into consent decrees or permanent injunctions under which specified promotional conduct is changed or curtailed.

In the United States, engaging in the impermissible promotion of any products, following approval, for off-label uses can also subject us to false claims and other litigation under federal and state statutes. These include fraud and abuse and consumer protection laws, which can lead to civil and criminal penalties and fines, agreements with governmental authorities that materially restrict the manner in which we promote or distribute therapeutic products and conduct our business. These restrictions could include corporate integrity agreements, suspension or exclusion from participation in federal and state healthcare programs, and suspension and debarment from government contracts and refusal of orders under existing government contracts. These False Claims Act lawsuits against manufacturers of drugs and biologics have increased significantly in volume and breadth, leading to several substantial civil and criminal settlements pertaining to certain sales practices and promoting off-label uses. In addition, False Claims Act lawsuits may expose manufacturers to follow-on claims by private payers based on fraudulent marketing practices. This growth in litigation has increased the risk that a biopharmaceutical company will have to defend a false claim action, pay settlement fines or restitution, as well as criminal and civil penalties, agree to comply with burdensome reporting and compliance obligations, and be excluded from Medicare, Medicaid, or other federal and state healthcare programs. If we do not lawfully promote our approved products, if any, we may become subject to such litigation and, if we do not successfully defend against such actions, those actions may have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

In the United States, the promotion of biopharmaceutical products is subject to additional FDA requirements and restrictions on promotional statements. If, after vidutolimod or any future product candidates obtains marketing approval, the FDA determines that our promotional activities violate its regulations and policies pertaining to product promotion, it could request that we modify our promotional materials or subject us to regulatory or other enforcement actions, including issuance of warning letters or untitled letters, suspension or withdrawal of an approved product from the market, requests for recalls, payment of civil fines, disgorgement of money, imposition of operating restrictions, injunctions or criminal prosecution, and other enforcement actions. Similarly, industry codes in foreign jurisdictions may prohibit companies from engaging in certain promotional activities, and regulatory agencies in various countries may enforce violations of such codes with civil penalties. If we become subject to regulatory and enforcement actions, our business, financial condition, results of operations, stock price and prospects will be materially harmed.

We have received orphan drug designation for vidutolimod, and we may in the future seek orphan drug status for additional indications for vidutolimod or for our future product candidates, but we may be unable to obtain such designations or to maintain the benefits associated with orphan drug status, including market exclusivity, which may cause our revenue, if any, to be reduced.

We have received Orphan Drug Designation for vidutolimod for Stage IIb-IV melanoma in the U.S., and we may seek Orphan Drug Designation for future product candidates. Regulatory authorities in some jurisdictions, including the U.S. and the European Union, may designate drugs for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may designate a product as an orphan drug if it is a drug

66

intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals in the U.S., or a patient population of greater than 200,000 individuals in the United States, but for which there is no reasonable expectation that the cost of developing the drug or biologic will be recovered from sales in the United States.

In the United States, orphan designation entitles a party to financial incentives such as opportunities for grant funding towards clinical trial costs, tax advantages and user-fee waivers. In addition, if a product with an Orphan Drug Designation subsequently receives the first marketing approval for the indication for which it has such designation, the product is entitled to a period of marketing exclusivity, which precludes the FDA or the EMA from approving another marketing application for the same drug for that time period.

The applicable period is seven years in the U.S. and ten years in the European Union. The exclusivity period in the European Union can be reduced to six years if a drug no longer meets the criteria for Orphan Drug Designation or if the drug is sufficiently profitable so that market exclusivity is no longer justified. Orphan Drug exclusivity may be lost if the FDA or EMA determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantity of the drug to meet the needs of patients with the rare disease or condition.

Even if we obtain Orphan Drug exclusivity for a product candidate, that exclusivity may not effectively protect the product candidate from competition because competing drugs containing a different active ingredient can be approved for the same condition. In addition, even after an orphan drug is approved, the FDA can subsequently approve the same drug for the same condition if the FDA concludes that the later drug is clinically superior in that it is shown to be safer, more effective or makes a major contribution to patient care. Orphan Drug Designation neither shortens the development time or regulatory review time of a drug nor gives the drug any advantage in the regulatory review or approval process.

We have received Fast Track designation by the FDA for vidutolimod for certain designations and may seek such designation for any future product candidates, but such designation may not lead to a faster development or regulatory review or approval process and does not increase the likelihood that vidutolimod and future product candidates will receive marketing approval.

If a drug is intended for the treatment of a serious or life-threatening condition and nonclinical or clinical data demonstrate the potential to address unmet medical needs for this condition, the drug sponsor may apply for FDA Fast Track designation for a particular indication. In July 2020, the FDA granted Fast Track designation for vidutolimod in combination with a PD-1 blocking antibody (nivolumab or pembrolizumab) in both anti-PD-1 refractory melanoma and first-line metastatic melanoma.

We may seek Fast Track designation for our future product candidates, but there is no assurance that the FDA will grant this designation to any of our product candidates. Marketing applications filed by sponsors of products receiving Fast Track designation may qualify for priority review under the policies and procedures offered by the FDA, but the Fast Track designation alone does not assure qualification for priority review. The FDA has broad discretion whether or not to grant Fast Track designation, so even if we believe a particular product candidate is eligible for this designation, there can be no assurance that the FDA would decide to grant it. Even though vidutolimod has received Fast Track designation, and any future product candidates may receive Fast Track designation, we may not experience a faster development, regulatory review or approval process compared to conventional FDA procedures, and receiving a Fast Track designation does not provide assurance of ultimate FDA approval or that approval will be granted in any particular time frame. In addition, the FDA may withdraw Fast Track designation at any time if it believes that the designation is no longer supported by data from our clinical development program or that the relevant criteria are no longer met.

We may attempt to secure approval from the FDA through the use of the accelerated approval pathway by the FDA. If we are unable to obtain such approval, we may be required to conduct additional preclinical studies or

67

clinical trials beyond those that we contemplate, which could increase the expense of obtaining, and delay the receipt of, necessary marketing approvals. Even if we receive accelerated approval from the FDA, if our confirmatory trials do not verify clinical benefit, or if we do not comply with rigorous post-marketing requirements, the FDA may seek to withdraw accelerated approval.

We currently intend to seek approval of vidutolimod for the treatment of refractory melanoma and first-line melanoma, and may seek approval of future product candidates, under the FDA’s accelerated approval pathway. A product may be eligible for accelerated approval if it is designed to treat a serious or life-threatening disease or condition and generally provides a meaningful advantage over available therapies upon a determination that the product candidate has an effect on a surrogate endpoint or intermediate clinical endpoint that is reasonably likely to predict clinical benefit. The FDA considers a clinical benefit to be a positive therapeutic effect that is clinically meaningful in the context of a given disease, such as irreversible morbidity or mortality. For the purposes of accelerated approval, a surrogate endpoint is a marker, such as a laboratory measurement, radiographic image, physical sign, or other measure that is thought to predict clinical benefit, but is not itself a measure of clinical benefit. An intermediate clinical endpoint is a clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality that is reasonably likely to predict an effect on irreversible morbidity or mortality or other clinical benefit. The accelerated approval pathway may be used in cases in which the advantage of a new drug over available therapy may not be a direct therapeutic advantage, but is a clinically important improvement from a patient and public health perspective. If granted, accelerated approval is usually contingent on the sponsor’s agreement to conduct, in a diligent manner, additional post-approval confirmatory studies to verify and describe the drug’s clinical benefit. If the sponsor fails to conduct such studies in a timely manner, or if such post-approval studies fail to verify the drug’s predicted clinical benefit, the FDA may withdraw its approval of the drug on an expedited basis.

Prior to seeking accelerated approval for vidutolimod or future product candidates, we would intend to seek feedback from the FDA and will otherwise evaluate our ability to seek and receive accelerated approval. There can be no assurance that after our evaluation of the feedback and other factors we will decide to pursue or submit a BLA for accelerated approval or any other form of expedited development, review or approval. Similarly, there can be no assurance that after subsequent FDA feedback we will continue to pursue or apply for accelerated approval or any other form of expedited development, review or approval, even if we initially decide to do so. Furthermore, if we decide to submit an application for accelerated approval or receive an expedited regulatory designation for our product candidates, there can be no assurance that such submission or application will be accepted or that any expedited development, review or approval will be granted on a timely basis, or at all. The FDA or other comparable foreign regulatory authorities could also require us to conduct further studies prior to considering our application or granting approval of any type. Specifically, during an end-of-Phase 1 meeting held in March 2020 to discuss our plans for a registration path for vidutolimod in melanoma, the FDA indicated that one single-arm Phase 2 trial may be unlikely to support accelerated approval of a BLA for vidutolimod for the treatment of anti-PD-1 refractory patients with metastatic or unresectable melanoma in combination with pembrolizumab, and recommended that we conduct a randomized trial in the proposed patient population to evaluate the contribution of each component to the potential treatment effect of the combination. A failure to obtain accelerated approval or any other form of expedited development, review or approval for our product candidate would result in a longer time period to commercialization of such product candidate, could increase the cost of development of such product candidate and could harm our competitive position in the marketplace.

Obtaining and maintaining regulatory approval of vidutolimod or any future product candidates in one jurisdiction does not mean that we will be successful in obtaining regulatory approval of vidutolimod or any future product candidates in other jurisdictions.

Obtaining and maintaining regulatory approval of vidutolimod or any future product candidates in one jurisdiction does not guarantee that we will be able to obtain or maintain regulatory approval in any other jurisdiction, while a failure or delay in obtaining regulatory approval in one jurisdiction may have a negative effect on the regulatory approval process in others. For example, even if the FDA grants marketing approval of a

68

product candidate, comparable regulatory authorities in foreign jurisdictions must also approve the manufacturing, marketing and promotion of the product candidate in those countries. Approval procedures vary among jurisdictions and can involve requirements and administrative review periods different from, and greater than, those in the United States, including additional preclinical studies or clinical trials, as clinical trials conducted in one jurisdiction may not be accepted by regulatory authorities in other jurisdictions. In many jurisdictions outside the United States, a product candidate must be approved for reimbursement before it can be approved for sale in that jurisdiction. In some cases, the price that we intend to charge for our products is also subject to approval.

We may also submit marketing applications in other countries. Regulatory authorities in jurisdictions outside of the United States have requirements for approval of product candidates with which we must comply prior to marketing in those jurisdictions. Obtaining foreign regulatory approvals and compliance with foreign regulatory requirements could result in significant delays, difficulties and costs for us and could delay or prevent the introduction of our products in certain countries. If we fail to comply with the regulatory requirements in international markets or receive applicable marketing approvals, our target markets will be reduced and our ability to realize the full market potential of vidutolimod or any future product candidates will be harmed.

Disruptions at the FDA and other government agencies caused by funding shortages or global health concerns could hinder their ability to hire, retain or deploy key leadership and other personnel, or otherwise prevent new or modified products from being developed, or approved or commercialized in a timely manner or at all, which could negatively impact our business.

The ability of the FDA and other government agencies to review and approve new products can be affected by a variety of factors, including government budget and funding levels, statutory, regulatory, and policy changes, the ability to hire and retain key personnel and accept the payment of user fees, and other events that may otherwise affect the ability to perform routine functions. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of other government agencies that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable. Disruptions at the FDA and other government agencies may also slow the time necessary for new drugs, medical devices and biologics or modifications to cleared or approved drugs, medical devices and biologics to be reviewed and approved by necessary government agencies, which would adversely affect our business. For example, over the last several years, including for 35 days beginning on December 22, 2018, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA, have had to furlough critical FDA employees and stop critical activities.

Since March 2020 when foreign and domestic inspections were largely placed on hold, the FDA has been working to resume routine surveillance, bioresearch monitoring and pre-approval inspections on a prioritized basis. Since April 2021, the FDA has conducted limited inspections and employed remote interactive evaluations, using risk management methods, to meet user fee commitments and goal dates. Ongoing travel restrictions and other uncertainties continue to impact oversight operations both domestic and abroad and it is unclear when standard operational levels will resume. The FDA is continuing to complete mission-critical work, prioritize other higher-tiered inspectional needs (e.g., for-cause inspections), and carry out surveillance inspections using risk-based approaches for evaluating public health. Should FDA determine that an inspection is necessary for approval and an inspection cannot be completed during the review cycle due to restrictions on travel, and the FDA does not determine a remote interactive evaluation to be adequate, the agency has stated that it generally intends to issue, depending on the circumstances, a complete response letter or defer action on the application until an inspection can be completed. During the COVID-19 public health emergency, a number of companies announced receipt of complete response letters due to the FDA’s inability to complete required inspections for their applications. Regulatory authorities outside the U.S. may adopt similar restrictions or other policy measures in response to the ongoing COVID-19 pandemic and may experience delays in their regulatory activities. Additionally, as of May 26, 2021, the FDA noted it is continuing to ensure timely reviews of applications for medical products during the COVID-19 pandemic in line with its user fee performance goals and conducting

69

mission critical domestic and foreign inspections to ensure compliance of manufacturing facilities with FDA quality standards. However, the FDA may not be able to maintain this pace and delays or setbacks are possible in the future. If a prolonged government shutdown occurs, or if global health concerns continue to prevent the FDA or other regulatory authorities from conducting their regular inspections, reviews, or other regulatory activities, it could significantly impact the ability of the FDA or other regulatory authorities to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

Even if vidutolimod or any future product candidates receive regulatory approval, we will be subject to ongoing obligations and continued regulatory review, which may result in significant additional expense and limit how we manufacture and market our products.

Any product candidate for which we may obtain marketing approval will be subject to extensive and ongoing requirements of and review by the FDA and comparable foreign regulatory authorities, including requirements related to the manufacturing processes, post-approval clinical data, labeling, packaging, distribution, adverse event reporting, storage, recordkeeping, export, import, advertising, marketing, and promotional activities for such product. These requirements further include submissions of safety and other post-marketing information, including manufacturing deviations and reports, registration and listing requirements, the payment of annual fees, continued compliance with current good manufacturing practices (“cGMPs”), requirements relating to manufacturing, quality control, quality assurance, applicable tracking and tracing requirements and corresponding maintenance of records and documents, and good clinical practices (“GCPs”) for any clinical trials that we conduct post-approval.

The FDA and comparable foreign regulatory authorities will continue to closely monitor the safety profile of any product even after approval. If the FDA or comparable foreign regulatory authorities become aware of new safety information after approval of any of vidutolimod and future product candidates, they may withdraw approval, issue public safety alerts, require labeling changes or establishment of a REMS or similar strategy, impose significant restrictions on a product’s indicated uses or marketing, or impose ongoing requirements for potentially costly post-approval studies or post-market surveillance. Any such restrictions could limit sales of the product.

We and any of our suppliers or collaborators, including our contract manufacturers, could be subject to periodic unannounced inspections by the FDA to monitor and ensure compliance with cGMPs and other FDA regulatory requirements. Application holders must further notify the FDA, and depending on the nature of the change, obtain FDA pre-approval for product and manufacturing changes. For certain commercial prescription drug and biologic products, manufacturers and other parties involved in the supply chain must also meet chain of distribution requirements and build electronic, interoperable systems for product tracking and tracing and for notifying the FDA of counterfeit, diverted, stolen and intentionally adulterated products or other products that are otherwise unfit for distribution in the United States.

In addition, later discovery of previously unknown adverse events or that the product is less effective than previously thought or other problems with any products, manufacturers or manufacturing processes, or failure to comply with regulatory requirements both before and after approval, may yield various negative results, including:

• restrictions on manufacturing, distribution, or marketing of such products;

• restrictions on the labeling, including required additional warnings, such as boxed warnings, contraindications, precautions, and restrictions on the approved indication or use;

• modifications to promotional pieces;

• issuance of corrective information;

• requirements to conduct post-marketing studies or other clinical trials;

70

• clinical holds or termination of clinical trials;

• requirements to establish or modify a REMS or similar strategy;

• changes to the way the product is administered to patients;

• liability for harm caused to patients or subjects;

• reputational harm;

• the product becoming less competitive;

• warning or untitled letters;

• suspension of marketing or withdrawal of the products from the market;

• regulatory authority issuance of safety alerts, Dear Healthcare Provider letters, press releases, or other communications containing warnings or other safety information about the product;

• refusal to approve pending applications or supplements to approved applications that we submit;

• recalls of products;

• fines, restitution or disgorgement of profits or revenues;

• suspension or withdrawal of marketing approvals;

• refusal to permit the import or export of our products;

• product seizure or detention;

• FDA debarment, suspension and debarment from government contracts, and refusal of orders under existing government contracts, exclusion from federal healthcare programs, consent decrees, or corporate integrity agreements; or

• injunctions or the imposition of civil or criminal penalties, including imprisonment.

Any of these events could prevent us from achieving or maintaining market acceptance of any particular product or could substantially increase the costs and expenses of commercializing such product, which in turn could delay or prevent us from generating significant revenues from its marketing and sale. Any of these events could further have other material and adverse effects on our operations and business and could adversely impact our business, financial condition, results of operations, stock price and prospects.

Further, the FDA’s policies or those of comparable foreign regulatory authorities may change and could impose extensive and ongoing regulatory requirements and obligations on any product candidate for which we obtain marketing approval. If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may lose any marketing approval that we may have obtained and be subject to regulatory enforcement action, which would adversely affect our business, prospects and ability to achieve or sustain profitability.

Healthcare legislative reform measures may have a material adverse effect on our business and results of operations.

The United States and many foreign jurisdictions have enacted or proposed legislative and regulatory changes affecting the healthcare system that could prevent or delay marketing approval of vidutolimod and future product candidates, restrict or regulate post-approval activities and affect our ability to profitably sell a product for which we obtain marketing approval. Changes in regulations, statutes or the interpretation of existing regulations could impact our business in the future by requiring, for example: (i) changes to our manufacturing arrangements; (ii) additions or modifications to product labeling; (iii) the recall or discontinuation of our products; or (iv) additional record-keeping requirements. If any such changes were to be imposed, they could adversely affect the operation of our business.

71

In the United States, there have been and continue to be a number of legislative initiatives to contain healthcare costs. For example, in March 2010, the Affordable Care Act (the “ACA”) was passed, which substantially changed the way healthcare is financed by both governmental and private insurers, and significantly impacted the U.S. pharmaceutical industry. The ACA, among other things, subjects biological products to potential competition by lower-cost biosimilars, addresses a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for drugs that are inhaled, infused, instilled, implanted or injected, increases the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extends the rebate program to individuals enrolled in Medicaid managed care organizations, establishes annual fees and taxes on manufacturers of certain branded prescription drugs, and creates a new Medicare Part D coverage gap discount program, in which manufacturers must agree to offer 70% (increased pursuant to the Bipartisan Budget Act of 2018, effective as of 2019) point-of-sale discounts off negotiated prices of applicable brand drugs to eligible beneficiaries during their coverage gap period, as a condition for the manufacturer’s outpatient drugs to be covered under Medicare Part D.

Since its enactment, there have been numerous judicial, administrative, executive, and legislative challenges to certain aspects of the ACA. On June 17, 2021, the U.S. Supreme Court dismissed the most recent judicial challenge to the ACA brought by several states without specifically ruling on the constitutionality of the ACA. Prior to the Supreme Court’s decision, President Biden issued an Executive Order to initiate a special enrollment period from February 15, 2021 through August 15, 2021 for purposes of obtaining health insurance coverage through the ACA marketplace. The Executive Order also instructed certain governmental agencies to review and reconsider their existing policies and rules that limit access to healthcare, including among others, reexamining Medicaid demonstration projects and waiver programs that include work requirements, and policies that create unnecessary barriers to obtaining access to health insurance coverage through Medicaid or the ACA. It is unclear how other healthcare reform measures of the Biden administrations or other efforts, if any, to challenge repeal or replace the ACA, will impact our business.

• Other legislative changes have been proposed and adopted in the United States since the ACA was enacted that may impact our business if we are able to commercialize any product candidates. In August 2011, the Budget Control Act of 2011, among other things, included aggregate reductions of Medicare payments to providers up to 2% per fiscal year, and, due to subsequent legislative amendments, including the Coronavirus Aid, Relief and Economic Security Act (“CARES Act”) will remain in effect through 2030 unless additional Congressional action is taken. Pursuant to the CARES Act, which was signed into law on March 27, 2020 to provide financial support and resources to individuals and businesses affected by the COVID-19 pandemic, and subsequent legislation, these reductions were suspended from May 1, 2020 through March 31, 2022. Then, a 1% payment reduction will occur beginning April 1, 2022 through June 30, 2022, and the 2% payment reduction will resume on July 1, 2022.

• In addition, the American Taxpayer Relief Act of 2012, among other things, reduced Medicare payments to several providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

• On April 13, 2017, CMS published a final rule that gives states greater flexibility in setting benchmarks for insurers in the individual and small group marketplaces, which may have the effect of relaxing the essential health benefits required under the ACA for plans sold through such marketplaces.

• Additionally, in May 2019, CMS issued a final rule to allow Medicare Advantage Plans the option of using step therapy, a type of prior authorization, for Part B drugs beginning January 1, 2020. This final rule codified CMS’s policy change that was effective January 1, 2019. However, it is unclear whether the Biden administration will challenge, reverse, revoke or otherwise modify these executive and administrative actions.

• On December 20, 2019, former President Trump signed into law the Further Consolidated Appropriations Act (H.R. 1865), which repealed the Cadillac tax, the health insurance provider tax, and

72

the medical device excise tax. It is impossible to determine whether similar taxes could be instated in the future.

There has been increasing legislative and enforcement interest in the United States with respect to specialty drug pricing practices. Specifically, there have been several recent U.S. Congressional inquiries and proposed federal and state legislation designed to, among other things, bring more transparency to drug pricing, reduce the cost of prescription drugs under Medicare, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for drugs. At the federal level, the former Trump administration’s budget for fiscal year 2021 included a $135 billion allowance to support legislative proposals seeking to reduce drug prices, increase competition, lower out-of-pocket drug costs for patients, and increase patient access to lower-cost generic and biosimilar drugs. At a federal level, the President Biden signed an Executive Order on July 9, 2021 affirming its policy (i) to support legislative reforms that would lower prescription drug prices, including by allowing Medicare to negotiate drug prices and by imposing inflation caps; and (ii) to support the enactment of a public health insurance option. Among other things, the Executive Order also directs HHS to submit a report to combat excessive pricing of prescription drugs, to enhance the domestic drug supply chain, to reduce the price that the Federal government pays for drugs, and to address price gouging in the industry; and directs the FDA to work with states to develop prescription drug importation plans pursuant to the Medicare Modernization Act of 2003 and FDA’s related implementing regulations. FDA released such implementing regulations on September 24, 2020, which went into effect on November 30, 2020, providing guidance for states to build and submit importation plans for drugs from Canada. Further, on November 20, 2020, CMS issued an Interim Final Rule implementing the Most Favored Nation, or MFN, Model under which Medicare Part B reimbursement rates will be calculated for certain drugs and biologicals based on the lowest price drug manufacturers receive in Organization for Economic Cooperation and Development countries with a similar gross domestic product per capita. The MFN Model regulations mandate participation by identified Part B providers and would have applied to all U.S. states and territories for a seven-year period beginning January 1, 2021, and ending December 31, 2027. However, in response to a lawsuit filed by several industry groups, on December 28, the U.S. District Court for the Northern District of California issued a nationwide preliminary injunction enjoining government defendants from implementing the MFN Rule pending completion of notice-and-comment procedures under the Administrative Procedure Act. On January 13, 2021, in a separate lawsuit brought by industry groups in the U.S. District of Maryland, the government defendants entered a joint motion to stay litigation on the condition that the government would not appeal the preliminary injunction granted in the U.S. District Court for the Northern District of California and that performance for any final regulation stemming from the MFN Interim Final Rule shall not commence earlier than 60 days after publication of that regulation in the Federal Register. Further, authorities in Canada have passed rules designed to safeguard the Canadian drug supply from shortages. If implemented, importation of drugs from Canada and the MFN Model may materially and adversely affect the price we receive for any of our product candidates. Additionally, on December 2, 2020, HHS published a regulation removing safe harbor protection for price reductions from pharmaceutical manufacturers to plan sponsors under Part D, either directly or through pharmacy benefit managers, unless the price reduction is required by law. The rule also creates a new safe harbor for price reductions reflected at the point-of-sale, as well as a safe harbor for certain fixed fee arrangements between pharmacy benefit managers and manufacturers. on December 2, 2020, HHS published a regulation removing safe harbor protection for price reductions from pharmaceutical manufacturers to plan sponsors under Part D, either directly or through pharmacy benefit managers, unless the price reduction is required by law. The rule also creates a new safe harbor for price reductions reflected at the point-of-sale, as well as a safe harbor for certain fixed fee arrangements between pharmacy benefit managers and manufacturers. Pursuant to court order, the removal and addition of the aforementioned safe harbors were delayed and recent legislation imposed a moratorium on implementation of the rule until January 1, 2026. Further, implementation of this change and new safe harbors for point-of-sale reductions in price for prescription pharmaceutical products and pharmacy benefit manager service fees are currently under review by the Biden administration and may be amended or repealed. Although a number of these and other proposed measures may require authorization through additional legislation to become effective, and the Biden administration may reverse or otherwise change these measures,

73

both the Biden administration and Congress have indicated that it will continue to seek new legislative measures to control drug costs.

On July 9, 2021, President Biden issued an executive order directing the FDA to work with states and tribes to safely import prescription drugs from Canada and to continue to clarify and improve the approval framework for generic drugs and biosimilars, including the standards for interchangeability of biological products, facilitate the development and approval of biosimilar and interchangeable products, clarify existing requirements and procedures related to the review and submission of BLAs, and identify and address any efforts to impede generic drug and biosimilar competition.

At the state level, individual state governments are increasingly becoming aggressive in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. In addition, regional health care authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other health care programs. These measures could reduce the ultimate demand for our products, if approved, or put pressure on our product pricing.

We expect that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for vidutolimod and future product candidates or additional pricing pressures.

Our revenue prospects could be affected by changes in healthcare spending and policy in the United States and abroad. We operate in a highly regulated industry and new laws, regulations or judicial decisions, or new interpretations of existing laws, regulations or decisions, related to healthcare availability, the method of delivery or payment for healthcare products and services could negatively impact our business, operations and financial condition.

There have been, and likely will continue to be, legislative and regulatory proposals at the foreign, federal and state levels directed at broadening the availability of healthcare and containing or lowering the cost of healthcare. We cannot predict the initiatives that may be adopted in the future, including repeal, replacement or significant revisions to the ACA. The continuing efforts of the government, insurance companies, managed care organizations and other payors of healthcare services to contain or reduce costs of healthcare and impose price controls may adversely affect:

• the demand for vidutolimod and future product candidates, if we obtain regulatory approval;

• our ability to set a price that we believe is fair for our products;

• our ability to obtain coverage and reimbursement approval for a product;

• our ability to generate revenue and achieve or maintain profitability;

• the level of taxes that we are required to pay; and

• the availability of capital.

Individual states in the United States have also become increasingly active in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain drug access and marketing cost disclosure and transparency measures, and designed to encourage importation from other countries and bulk purchasing. Legally mandated price controls on payment amounts by third-party payors or other restrictions could harm our business, financial condition, results of operations and prospects. In addition, regional healthcare authorities and

74

individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. This could reduce the ultimate demand for our drugs or put pressure on our drug pricing, which could negatively affect our business, financial condition, results of operations and prospects. Any reduction in reimbursement from Medicare or other government programs may result in a similar reduction in payments from private payors, which may adversely affect our future profitability.

Our relationships with patients and third-party payors will be subject to applicable anti-kickback, fraud and abuse and other healthcare laws and regulations, which could expose us to criminal sanctions, civil penalties, exclusion from government healthcare programs, contractual damages, reputational harm and diminished profits and future earnings.

Although we do not currently have any drugs on the market, once we begin commercializing vidutolimod and future product candidates, if approved, we will be subject to additional healthcare statutory and regulatory requirements and enforcement by the federal government and the states and foreign governments in which we conduct our business. Healthcare providers, physicians and third-party payors will play a primary role in the recommendation and prescription of vidutolimod and future product candidates for which we obtain marketing approval. Our future arrangements with third-party payors and customers may expose us to broadly applicable fraud and abuse and other healthcare laws and regulations that may constrain the business or financial arrangements and relationships through which we market, sell and distribute vidutolimod and future product candidates for which we obtain marketing approval. Restrictions under applicable federal and state healthcare laws and regulations, include the following:

• the federal Anti-Kickback Statute prohibits, among other things, persons from knowingly and willfully soliciting, offering, receiving or providing remuneration, directly or indirectly, in cash or in kind, to induce or reward either the referral of an individual for, or the purchase, order or recommendation of, any good or service, for which payment may be made under federal and state healthcare programs such as Medicare and Medicaid. A person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation. Violations are subject to civil and criminal fines and penalties for each violation, plus up to three times the remuneration involved, imprisonment, and exclusion from government healthcare programs. In addition, the government may assert that a claim including items or services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the federal False Claims Act or federal civil money penalties;

• the federal civil and criminal false claims laws and civil monetary penalty laws, such as the federal False Claims Act, impose criminal and civil penalties, including through civil whistleblower or qui tam actions, against individuals or entities for knowingly presenting, or causing to be presented, to the federal government, claims for payment that are false or fraudulent or making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government. In addition, the government may assert that a claim including items and services resulting from a violation of the federal Anti-Kickback Statute constitutes a false of fraudulent claim for purposes of the False Claims Act. Manufacturers can be held liable under the federal False Claims Act even when they do not submit claims directly to government payors if they are deemed to “cause” the submission of false or fraudulent claims. The federal False Claims Act also permits a private individual acting as a “whistleblower” to bring actions on behalf of the federal government alleging violations of the federal False Claims Act and to share in any monetary recovery;

• the federal Health Insurance Portability and Accountability Act of 1996 (“HIPAA”), imposes criminal and civil liability for executing a scheme to defraud any healthcare benefit program, or knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false statement in connection with the delivery of or payment for healthcare benefits, items or services; similar to the federal Anti-Kickback Statute, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation;

75

• the federal physician payment transparency requirements, sometimes referred to as the “Sunshine Act” under the ACA require manufacturers of drugs, devices, biologics and medical supplies that are reimbursable under Medicare, Medicaid, or the Children’s Health Insurance Program to report to HHS information related to physician (defined to include doctors, dentists, optometrists, podiatrists and chiropractors) payments and other transfers of value and the ownership and investment interests of such physicians and their immediate family members. Effective January 1, 2022, these reporting obligations will extend to include transfers of value made in the previous year to certain nonphysician providers (physician assistants, nurse practitioners, clinical nurse specialists, certified registered nurse anesthetists and anesthesiologist assistants, and certified-nurse midwives) such as physician assistants and nurse practitioners;

• HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 (the “HITECH Act”) and its implementing regulations, including the Final Omnibus Rule published in January 2013, which also imposes obligations on certain covered entity healthcare providers, health plans, and healthcare clearinghouses as well as their business associates that perform certain services involving the creation, maintenance, receipt, use or disclosure of individually identifiable health information, including mandatory contractual terms, with respect to safeguarding the privacy, security and transmission of individually identifiable health information. HITECH also created new tiers of civil monetary penalties, amended HIPAA to make civil and criminal penalties directly applicable to business associates, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorneys’ fees and costs associated with pursuing federal civil actions. In addition, there may be additional federal, state and non-U.S. laws which govern the privacy and security of health and other personal information in certain circumstances, many of which differ from each other in significant ways and may not have the same effect, thus complicating compliance efforts;

• analogous state laws and regulations, such as state anti-kickback and false claims laws, which may apply to sales or marketing arrangements and claims involving healthcare items or services reimbursed by non-governmental third-party payors, including private insurers, and may be broader in scope than their federal equivalents; some state laws require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the federal government in addition to requiring drug manufacturers to report information related to payments to physicians and other health care providers or marketing expenditures. In addition, some states have passed laws that require pharmaceutical companies to comply with the April 2003 Office of Inspector General Compliance Program Guidance for Pharmaceutical Manufacturers and/or the Pharmaceutical Research and Manufacturers of America’s Code on Interactions with Healthcare Professionals. Several states also impose other marketing restrictions or require pharmaceutical companies to make marketing or price disclosures to the state and require the registration of pharmaceutical sales representatives. State and foreign laws, including for example the European Union General Data Protection Regulation, which became effective May 2018 also govern the privacy and security of personal data, including health information in some circumstances, many of which differ from each other in significant ways and often are not preempted by HIPAA, thus complicating compliance efforts. There are ambiguities as to what is required to comply with these state requirements and if we fail to comply with an applicable state law requirement, we could be subject to penalties; and

• state laws governing the privacy and security of health information in certain circumstances, many of which differ from each other in significant ways and often are not preempted by HIPAA, thus complicating compliance efforts, and analogous foreign laws and regulations.

Because of the breadth of these laws and the narrowness of the statutory exceptions and safe harbors available, it is possible that some of our business activities could be subject to challenge and may not comply under one or more of such laws, regulations, and guidance. Law enforcement authorities are increasingly focused on enforcing

76

fraud and abuse laws, and it is possible that some of our practices may be challenged under these laws. Ensuring that our future business arrangements with third parties comply with applicable healthcare laws and regulations could involve substantial costs. We have entered into certain advisory board and consulting agreements with physicians, including some who are compensated in the form of stock or stock options who may influence the ordering or use of our product candidates, if approved, in the future. It is possible that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations, including anticipated activities to be conducted by our sales team, were to be found to be in violation of any of these laws or any other governmental regulations that may apply to us, we may be subject to significant civil, criminal and administrative penalties, damages, fines, exclusion from government funded healthcare programs, such as Medicare and Medicaid, and the curtailment or restructuring of our operations. If any of the physicians or other providers or entities with whom we expect to do business is found to be not in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs.

Federal and state enforcement bodies have recently increased their scrutiny of interactions between healthcare companies and healthcare providers, which has led to a number of investigations, prosecutions, convictions and settlements in the healthcare industry. Ensuring that our internal operations and future business arrangements with third parties comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations, agency guidance or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that may apply to us, we may be subject to significant penalties, including administrative, civil and criminal penalties, damages, fines, disgorgement, the exclusion from participation in federal and state healthcare programs, individual imprisonment, reputational harm, and the curtailment or restructuring of our operations, as well as additional reporting obligations and oversight if we become subject to a corporate integrity agreement or other agreement to resolve allegations of non-compliance with these laws. Further, defending against any such actions can be costly and time consuming, and may require significant financial and personnel resources. Therefore, even if we are successful in defending against any such actions that may be brought against us, our business may be impaired. If any of the physicians or other providers or entities with whom we expect to do business are found to not be in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs and imprisonment. If any of the above occur, our ability to operate our business and our results of operations could be adversely affected.

Our future growth may depend, in part, on our ability to penetrate foreign markets, where we would be subject to additional regulatory burdens and other risks and uncertainties.

Our future profitability may depend, in part, on our ability to commercialize vidutolimod and future product candidates in foreign markets for which we may rely on collaborations with third parties. We are not permitted to market or promote any of vidutolimod and future product candidates before we receive regulatory approval from the applicable regulatory authority in that foreign market, and we may never receive such regulatory approval for vidutolimod or any future product candidates. To obtain separate regulatory approval in many other countries we must comply with numerous and varying regulatory requirements of such countries regarding safety and efficacy and governing, among other things, clinical trials and commercial sales, pricing and distribution of vidutolimod and future product candidates, and we cannot predict success in these jurisdictions. If we obtain approval of vidutolimod and future product candidates and ultimately commercialize vidutolimod and future product candidates in foreign markets, we would be subject to additional risks and uncertainties, including:

• our customers’ ability to obtain reimbursement for vidutolimod and future product candidates in foreign markets;

• our inability to directly control commercial activities because we are relying on third parties;

77

• the burden of complying with complex and changing foreign regulatory, tax, accounting and legal requirements;

• different medical practices and customs in foreign countries affecting acceptance in the marketplace;

• import or export licensing requirements;

• longer accounts receivable collection times;

• longer lead times for shipping;

• language barriers for technical training;

• reduced protection of intellectual property rights in some foreign countries;

• potential liability under the Foreign Corrupt Practices Act of 1977 or comparable foreign regulations;

• the existence of additional potentially relevant third-party intellectual property rights;

• foreign currency exchange rate fluctuations; and

• the interpretation of contractual provisions governed by foreign laws in the event of a contract dispute.

Foreign sales of vidutolimod and future product candidates could also be adversely affected by the imposition of governmental controls, political and economic instability, trade restrictions and changes in tariffs. For example, in some countries of the European Union, the pricing of prescription pharmaceuticals is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take considerable time after the receipt of marketing approval for a drug. To obtain reimbursement or pricing approval in some countries, we, or our future collaborators, may be required to conduct a clinical trial that compares the cost effectiveness of our drug to other available therapies. If reimbursement of our drugs is unavailable or limited in scope or amount, or if pricing is set at unsatisfactory levels, our business could be materially harmed.

Risks related to intellectual property

If we are unable to obtain, maintain and protect our intellectual property rights for our technology and our product candidates, or if our intellectual property rights are inadequate, our competitive position could be harmed.

Our commercial success will depend in part on our ability to obtain and maintain patent and other intellectual property protection in the United States and other countries with respect to our VLP and other technology, vidutolimod and future product candidates. We rely on trade secret, patent, copyright and trademark laws, and confidentiality, licensing and other agreements with employees and third parties, all of which offer only limited protection. We seek to protect our proprietary position by filing and prosecuting patent applications in the United States and abroad related to our technology and vidutolimod and future product candidates.

The patent positions of biotechnology and pharmaceutical companies generally are highly uncertain, involve complex legal and factual questions and have in recent years been the subject of much litigation. As a result, the issuance, scope, validity, enforceability and commercial value of our licensed patents and any patents we own in the future are highly uncertain. The steps we have taken to protect our proprietary rights may not be adequate to preclude misappropriation of our proprietary information or infringement of our intellectual property rights, both inside and outside of the United States.

Further, the examination process may require us to narrow the claims for our pending patent applications, which may limit the scope of patent protection that may be obtained if these applications issue. The scope of a patent may also be reinterpreted after issuance. The rights that may be granted under our future issued patents may not provide us with the proprietary protection or competitive advantages we are seeking. If we are unable to obtain and maintain patent protection for our technology or for vidutolimod or any future product candidates, or if the

78

scope of the patent protection obtained is not sufficient, our competitors could develop and commercialize products similar or superior to ours, and our ability to successfully commercialize vidutolimod or any future product candidates and future technologies may be adversely affected. It is also possible that we will fail to identify patentable aspects of inventions made in the course of our development and commercialization activities before it is too late to obtain patent protection on them.

In addition, the patent prosecution process is expensive, time-consuming and complex, and we may not be able to file, prosecute, maintain, enforce or license all necessary or desirable patent applications at a reasonable cost or in a timely manner. Although we enter into non-disclosure and confidentiality agreements with parties who have access to confidential or patentable aspects of our research and development output, such as our employees, collaborators, and other third parties, any of these parties may breach the agreements and disclose such output before a patent application is filed, thereby jeopardizing our ability to seek patent protection. It is also possible that we will fail to identify patentable aspects of our research and development efforts in time to obtain patent protection.

For the core technology related to vidutolimod and its component parts, we are prosecuting seven families of patent applications which we own including composition of matter, methods of use, combination therapies, drug delivery, dose volume, aggregation, packaging and pDC recruitment claims. Further, we have an exclusive license for seven families of patents and patent applications including composition of matter, manufacturing methods, aggregation, packaging and synthesis claims. Some patents have issued in the United States and internationally and additional patent applications are pending in the United States and internationally (either in foreign jurisdictions or under the Patent Cooperation Treaty (“PCT”)). As of March 6, 2022, we own or exclusively license the rights to 13 issued US granted patents, 131 granted patents outside of the US, and 29 pending patent applications worldwide. Any future provisional patent applications are not eligible to become issued patents until, among other things, we file a non-provisional patent application within 12 months of filing of one or more of our related provisional patent applications. If we do not timely file any non-provisional patent applications, we may lose our priority date with respect to our provisional patent applications and any patent protection on the inventions disclosed in our provisional patent applications. Although we intend to timely file non-provisional patent applications relating to our provisional patent applications, we cannot predict whether any of our future patent applications will result in the issuance of patents that effectively protect our technology or vidutolimod or any future product candidates, or if any of our future issued patents will effectively prevent others from commercializing competitive products. Publications of discoveries in the scientific literature often lag behind the actual discoveries, and patent applications in the United States and other jurisdictions are typically not published until 18 months after filing or in some cases not at all until they are issued as a patent. Therefore, we cannot be certain that we were the first to make the inventions claimed in our pending patent applications, or that we were the first to file for patent protection of such inventions.

Our pending applications cannot be enforced against third parties practicing the inventions claimed in such applications unless and until a patent issues from such applications. Because the issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability, issued patents that we license from third parties or own in the future may be challenged in the courts or patent offices in the United States and abroad, including through opposition proceedings, derivation proceedings, inter partes review, interference proceedings or litigation. Such proceedings may result in the loss of patent protection, the narrowing of claims in such patents or the invalidity or unenforceability of such patents, which could limit our ability to stop others from using or commercializing similar or identical products, or limit the duration of the patent protection for our technology. Protecting against the unauthorized use of our patented inventions, trademarks and other intellectual property rights is expensive, time consuming, difficult and in some cases may not be possible. In some cases, it may be difficult or impossible to detect third-party infringement or misappropriation of our intellectual property rights, even in relation to issued patent claims, and proving any such infringement may be even more difficult. If we are unable to obtain, maintain, and protect our intellectual property our competitive advantage could be harmed, and it could result in a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

79

If we fail to comply with our obligations in the agreements under which we collaborate with or license intellectual property rights from third parties, or otherwise experience disruptions to our business relationships with our licensors, we could lose intellectual property rights that are important to our business.

We are a party to the Kuros License Agreement and we expect to enter into additional license agreements in the future. The Kuros License Agreement imposes, and we expect that future license agreements will impose, various diligence, milestone payment, royalty and other obligations on us. In spite of our efforts, Kuros and any future licensors may allege that we have materially breached our obligations under the relevant license agreement and may therefore attempt to terminate the license agreements, thereby removing or limiting our ability to develop and commercialize products and technology covered by these license agreements. If these in-licenses are terminated, or if the underlying patents fail to provide the intended exclusivity, competitors or other third parties might have the freedom to seek regulatory approval of, and to market, products identical to ours and we may be required to cease our development and commercialization of our lead products or other product candidates that we may identify. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations, and prospects.

Moreover, disputes may arise regarding intellectual property subject to a licensing agreement, including:

• the scope of rights granted under the license agreement and other interpretation-related issues;

• the extent to which our product candidates, technology and processes infringe on intellectual property of the licensor that is not subject to the licensing agreement;

• the sublicensing of patent and other rights under our collaborative development relationships;

• our diligence obligations under the license agreement and what activities satisfy those diligence obligations;

• the inventorship and ownership of inventions and know-how resulting from the joint creation or use of intellectual property by our licensors and us and our third-party vendors; and

• the priority of invention of patented technology.

In addition, the agreements under which we currently license intellectual property or technology from third parties are complex, and certain provisions in such agreements may be susceptible to multiple interpretations. The resolution of any contract interpretation disagreement that may arise could narrow what we believe to be the scope of our rights to the relevant intellectual property or technology, or increase what we believe to be our financial or other obligations under the relevant agreement, either of which could have a material adverse effect on our business, financial condition, results of operations, and prospects. Moreover, if disputes over intellectual property that we have licensed prevent or impair our ability to maintain our current licensing arrangements on commercially acceptable terms, we may be unable to successfully develop and commercialize the affected product candidates, which could have a material adverse effect on our business, financial conditions, results of operations, and prospects.

If we are unable to protect the confidentiality of our proprietary information and know-how, the value of our technology and products could be adversely affected.

In addition to seeking patent protection, we also rely on other proprietary rights, including protection of trade secrets, know-how and confidential and proprietary information. To maintain the confidentiality of our trade secrets and proprietary information, we enter into confidentiality agreements with our employees, consultants, collaborators and other third parties who have access to our trade secrets. Our agreements with employees also provide that any inventions conceived by the individual in the course of rendering services to us shall be our exclusive property. However, we may not obtain these agreements in all circumstances, and individuals with whom we have these agreements may not comply with their terms. The assignment of intellectual property rights may not be self-executing or the assignment agreements may be breached, and we may be forced to bring claims

80

against third parties, or defend claims that they may bring against us, to determine the ownership of what we regard as our intellectual property. In addition, in the event of unauthorized use or disclosure of our trade secrets or proprietary information, these agreements, even if obtained, may not provide meaningful protection, particularly for our trade secrets or other confidential information. To the extent that our employees, consultants or contractors use technology or know-how owned by third parties in their work for us, disputes may arise between us and those third parties as to the rights in related inventions.

Adequate remedies may not exist in the event of unauthorized use or disclosure of our confidential information including a breach of our confidentiality agreements. Enforcing a claim that a party illegally disclosed or misappropriated a trade secret is difficult, expensive, and time consuming, and the outcome is unpredictable. In addition, some courts in and outside of the United States are less willing or unwilling to protect trade secrets. If any of our trade secrets were to be lawfully obtained or independently developed by a competitor or other third party, we would have no right to prevent them from using that technology or information to compete with us. The disclosure of our trade secrets or the independent development of our trade secrets by a competitor or other third party would impair our competitive position and may materially harm our business, financial condition, results of operations, stock price and prospects.

We may not be able to protect our intellectual property and proprietary rights throughout the world.

Filing, prosecuting and defending patents on our technology throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States can be less extensive than those in the United States. In addition, the laws and practices of some foreign countries do not protect intellectual property rights to the same extent as federal and state laws in the United States. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States, or from selling or importing products made using our inventions in and into the United States or other jurisdictions. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop or manufacture their own products, and may export otherwise infringing products to territories where we have patent protection but where enforcement is not as strong as that in the United States. These products may compete with our products and our patent claims or other intellectual property rights may not be effective or sufficient to prevent them from so competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in certain foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the granting or enforcement of patents, trade secrets and other intellectual property protection, particularly those relating to biopharmaceuticals, which could make it difficult for us to obtain patent rights or stop the infringement of our patents or marketing of competing products in violation of our intellectual property and proprietary rights generally in those countries. Proceedings to enforce our intellectual property and proprietary rights in foreign jurisdictions could result in substantial cost and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly and our patent applications at risk of not issuing and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate and the damages or other remedies awarded, if any, may not be commercially meaningful. Accordingly, our efforts to protect and enforce our intellectual property and proprietary rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property we develop or license.

In addition, the laws of certain foreign countries may not protect our rights to the same extent as the laws of the United States, and those foreign laws may also be subject to change. For example, methods of treatment and manufacturing processes may not be patentable in certain jurisdictions, and the requirements for patentability may differ in certain countries. Furthermore, biosimilar product manufacturers or other competitors may challenge the scope, validity and enforceability of our patents, requiring us to engage in complex, lengthy and costly litigation or proceedings.

81

Moreover, many countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties. Many countries limit the enforceability of patents against government agencies or government contractors. In these countries, the patent owner may have limited remedies, which could materially diminish the value of such patent. If we are forced to grant a license to third parties with respect to any patents relevant to our business, our competitive position may be impaired and our business and results of operations may be adversely affected.

Obtaining and maintaining patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

The U.S. Patent and Trademark Office (the “USPTO”) and various foreign governmental patent agencies require compliance with a number of procedural, documentary, fee payments and other similar provisions during the patent application process and to maintain patents after they are issued. For example, periodic maintenance fees, renewal fees, annuity fees and various other government fees on issued patents and patent applications often must be paid to the USPTO and foreign patent agencies over the lifetime of our licensed patents or any patents we own in the future. In certain circumstances, we may rely on future licensing partners to take the necessary action to comply with these requirements with respect to licensed intellectual property. Although an unintentional lapse can be cured for a period of time by payment of a late fee or by other means in accordance with the applicable rules, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. Non-compliance events that could result in abandonment or lapse of a patent or patent application include, but are not limited to, failure to respond to official actions within prescribed time limits, non-payment of fees and failure to properly legalize and submit formal documents. If we fail to obtain and maintain the patents and patent applications covering our products or procedures, we may not be able to stop a competitor from marketing products that are the same as or similar to vidutolimod or any future product candidates, which could have a material adverse effect on our business.

Changes to the patent law in the United States and other jurisdictions could diminish the value of patents in general, thereby impairing our ability to protect vidutolimod and future product candidates.

As is the case with other biopharmaceutical companies, our success is heavily dependent on intellectual property, particularly patents. Obtaining and enforcing patents in the biopharmaceutical industry involves both technological and legal complexity and is therefore costly, time consuming and inherently uncertain. Changes in either the patent laws or interpretation of the patent laws in the United States could increase the uncertainties and costs. Patent reform legislation in the United States and other countries, including the Leahy-Smith America Invents Act (the “Leahy-Smith Act”), signed into law on September 16, 2011, could increase those uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents. The Leahy-Smith Act includes a number of significant changes to U.S. patent law. These include provisions that affect the way patent applications are prosecuted, redefine prior art and provide more efficient and cost-effective avenues for competitors to challenge the validity of patents. They also include allowing third-party submission of prior art to the USPTO during patent prosecution and additional procedures to attack the validity of a patent by USPTO administered post-grant proceedings, including post-grant review, inter partes review, and derivation proceedings. After March 2013, under the Leahy-Smith Act, the United States transitioned to a first inventor to file system in which, assuming that the other statutory requirements are met, the first inventor to file a patent application will be entitled to the patent on an invention regardless of whether a third party was the first to invent the claimed invention. However, the Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

The U.S. Supreme Court has ruled on several patent cases in recent years, either narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations.

82

Depending on future actions by the U.S. Congress, the U.S. courts, the USPTO and the relevant law-making bodies in other countries, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce our existing patents and patents that we might obtain in the future.

Patent terms may be inadequate to protect our competitive position with respect to vidutolimod and future product candidates for an adequate amount of time.

Given the amount of time required for the development, testing and regulatory review of new product candidates, such as vidutolimod and future product candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. In the United States, the Drug Price Competition and Patent Term Restoration Act of 1984 permits a patent term extension of up to five years beyond the normal expiration of the patent, but no longer than 14 years from the product’s approval date, which is limited to the approved indication (or any additional indications approved during the period of extension). However, the applicable authorities, including the USPTO in the United States, and any equivalent regulatory authorities in other countries, may not agree with our assessment of whether such extensions are available, and may refuse to grant extensions to our patents, or may grant more limited extensions than we request. If this occurs, our competitors may be able to take advantage of our investment in development and clinical trials by referencing our clinical and preclinical data and launch their products earlier than might otherwise be the case, which could have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

Vidutolimod and future product candidates for which we intend to seek approval as biologic products may face competition sooner than anticipated.

Vidutolimod is a biological product candidate. We believe that any of our product candidates approved in the United States as a biological product under a BLA should qualify for the 12-year period of regulatory exclusivity. The enactment of the Biologics Price Competition and Innovation Act of 2009 (“BPCIA”) as part of the ACA, created an abbreviated pathway for the approval of biosimilar and interchangeable biological products. The abbreviated regulatory pathway establishes legal authority for the FDA to review and approve biosimilar biologics, including the possible designation of a biosimilar as “interchangeable” based on its similarity to an existing brand product. Under the BPCIA, an application for a biosimilar product cannot be approved by the FDA until 12 years after the original branded product was approved under a BLA. Certain changes, however, and supplements to an approved BLA, and subsequent applications filed by the same sponsor, manufacturer, licensor, predecessor in interest, or other related entity do not qualify for the 12-year exclusivity period. The law is complex and is still being interpreted and implemented by the FDA. As a result, its ultimate impact, implementation, and meaning are subject to uncertainty. While it is uncertain when such processes intended to implement the BPCIA may be fully adopted by the FDA, any such processes could have a material adverse effect on the future commercial prospects for our biological products.

However, there is also a risk that this exclusivity could be changed in the future. For example, this exclusivity could be shortened due to congressional action or through other actions, including future proposed budgets, international trade agreements and other arrangements or proposals. The extent to which a biosimilar, once approved, will be substituted for any one of our reference products in a way that is similar to traditional generic substitution for non-biological products is not yet clear, and will depend on a number of marketplace and regulatory factors that are still developing. It is also possible that payers will give reimbursement preference to biosimilars over reference biologics, even absent a determination of interchangeability.

To the extent that we do not receive any anticipated periods of regulatory exclusivity for vidutolimod and future product candidates or the FDA or foreign regulatory authorities approve any biosimilar, interchangeable, or other competing products to vidutolimod and future product candidates, it could have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

83

Intellectual property rights do not necessarily address all potential threats.

The degree of future protection afforded by our intellectual property rights is uncertain because intellectual property rights have limitations and may not adequately protect our business or permit us to maintain our competitive advantage. For example:

• we, or our current or future collaborators, might not have been the first to file patent applications covering certain of our or their inventions;

• others may independently develop similar or alternative technologies or duplicate our technology without infringing our owned or in-licensed intellectual property rights;

• it is possible that our pending patent applications or those we may own or in-license in the future will not lead to issued patents;

• issued patents that we hold rights to may be held invalid or unenforceable, including as a result of legal challenges by our competitors;

• our competitors might conduct research and development activities in countries where we do not have patent rights and then use the information learned from such activities to develop competitive products for sale in our major commercial markets;

• we cannot ensure that any of our pending patent applications, if issued, or those of our licensors, will include claims having a scope sufficient to protect our product candidates;

• we cannot ensure that any patents issued to us or our licensors will provide a basis for an exclusive market for our commercially viable product candidates or will provide us with any competitive advantages;

• we cannot ensure that our commercial activities or product candidates will not infringe upon the patents of others;

• we cannot ensure that we will be able to successfully commercialize our product candidates on a substantial scale, if approved, before the relevant patents that we own or license expire;

• we may not develop additional proprietary technologies that are patentable;

• the patents of others may harm our business; and

• we may choose not to file a patent in order to maintain certain trade secrets or know-how, and a third party may subsequently file a patent covering such intellectual property.

Should any of these events occur, they could have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

Third parties may in the future initiate legal proceedings alleging that we are infringing their intellectual property rights, the outcome of which would be uncertain and could harm our business.

Our commercial success depends on our ability and the ability of our current or future collaborators to develop, manufacture, market and sell vidutolimod and future product candidates, and to use our related proprietary technologies without infringing, misappropriating or otherwise violating the intellectual property and proprietary rights of third parties. The biotechnology and pharmaceutical industries are characterized by extensive litigation regarding patents and other intellectual property rights. We may become party to, or threatened with, adversarial proceedings or litigation regarding intellectual property rights with respect to vidutolimod and future product candidates, including interference proceedings, post-grant review, inter partes review and derivation proceedings before the USPTO. Third parties may assert infringement or other intellectual property claims against us based on existing patents or patents that may be granted in the future. If we are found to infringe a third party’s intellectual property rights, and we are unsuccessful in demonstrating that such intellectual property rights are

84

invalid or unenforceable, we could be required to obtain a license from such third party to continue developing, manufacturing and commercializing vidutolimod and future product candidates. However, we may not be able to obtain any required license on commercially reasonable terms or at all. Even if we were able to obtain a license, it could be non-exclusive, thereby giving our competitors and other third parties access to the same technologies licensed to us, and it could require us to make substantial licensing and royalty payments. We also could be forced, including by court order, to cease developing, manufacturing, and commercializing vidutolimod or any future product candidates. In addition, in any such proceeding or litigation, we could be found liable for significant monetary damages, including treble damages and attorneys’ fees, if we are found to have willfully infringed a patent or other intellectual property right. Any of the foregoing could have a material adverse effect on our business, financial condition, results of operations, stock price and prospects. Any claims by third parties that we have misappropriated their confidential information or trade secrets could have a similar material adverse effect on our business.

In addition, we are developing vidutolimod in combination with certain PD-1 blocking antibodies, including avelumab, pembrolizumab and nivolumab and cemiplimab, which are covered by patents or licenses held by Merck and Pfizer, or Merck US, BMS and Regeneron, respectively, to which we do not have a license other than for use in connection with the applicable clinical trial. We also may develop any future product candidates in combination with products developed by additional companies that are covered by patents or licenses held by those entities to which we do not have a license. In the event that a labeling instruction is required in product packaging recommending that combination, we could be accused of, or held liable for, infringement of the third-party patents covering the product candidate or product recommended for administration with vidutolimod or any future product candidates. In such a case, we could be required to obtain a license from the other company or institution to use the required or desired package labeling, which may not be available on commercially reasonable terms, or at all.

We may become involved in lawsuits to protect or enforce our intellectual property, which could be expensive, time-consuming and unsuccessful and have a material adverse effect on the success of our business.

Competitors may infringe any licensed patents or any patent we own or misappropriate or otherwise violate our intellectual property rights. We may also be required to defend against claims of infringement and our licensed patents and any patents we own may become involved in priority or other intellectual property related disputes. To counter infringement or unauthorized use, litigation may be necessary in the future to enforce or defend our intellectual property rights, to protect our trade secrets or to determine the validity and scope of our own intellectual property rights or the proprietary rights of others. Also, third parties may initiate legal proceedings against us to assert that we are infringing their intellectual property rights or to challenge the validity or scope of our owned or licensed intellectual property rights. These proceedings can be expensive and time consuming. Many of our current and potential competitors have the ability to dedicate substantially greater resources to conduct intellectual property related litigations or proceedings than we can. We may not have sufficient financial or other resources to conduct such litigation or proceedings adequately. Accordingly, despite our efforts, we may not be able to prevent third parties from infringing upon or misappropriating our intellectual property. Litigation and other intellectual property related proceedings could result in substantial costs and diversion of management resources, which could harm our business and financial results. In addition, in an infringement proceeding, a court may decide that a patent owned by or licensed to us is invalid or unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that our patents do not cover the technology in question. An adverse result in any litigation or other intellectual property related proceeding could put one or more of our patents at risk of being invalidated, held unenforceable or interpreted narrowly.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation in the United States, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. There could also be public announcements of the results of hearings, motions or other interim proceedings or developments in any such proceedings. If securities analysts or investors perceive these results to be negative, it could have a material adverse effect on the price of shares of our common

85

stock. Any of the foregoing may have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

We may be subject to claims by third parties asserting that our collaborators, employees or we have misappropriated their intellectual property, or claiming ownership of what we regard as our own intellectual property.

Many of our employees, including our senior management team, were previously employed at, or consulted for, universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Our collaborators’ employees may currently be or previously have been employed at universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Some of these persons, including each member of our senior management team, executed proprietary rights, non-disclosure and non-competition agreements, or similar agreements, in connection with such previous employment or consulting agreements, that assigned ownership of intellectual property relating to work performed under such agreements to the contracting third party. Although we try to ensure that our employees do not use, claim as theirs, or misappropriate the intellectual property, proprietary information or know-how of others in their work for us, we may be subject to claims that we or these employees have used, claimed as theirs, misappropriated or disclosed intellectual property, including trade secrets or other proprietary information, of any such individual’s current or former employer. Litigation may be necessary to defend against such claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel or sustain damages. Such intellectual property rights could be awarded to a third party, and we could be required to obtain a license from such third party to commercialize our technology or products. Such a license may not be available on commercially reasonable terms, or at all. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management. Any of the foregoing may have a material adverse effect on our business, financial condition, results of operations, stock price and prospects.

We may be subject to damages resulting from claims that we or our employees have wrongfully used or disclosed confidential information of third parties or are in breach of non-competition or non-solicitation agreements with our competitors.

We could be subject to claims that we or our employees, including senior management, have inadvertently or otherwise used or disclosed alleged trade secrets or other confidential information of former employers or competitors or others. Although we try to ensure that our employees and consultants do not use the intellectual property, proprietary information, know-how or trade secrets of others in their work for us, we may be subject to claims that we caused an employee to breach the terms of their non-competition or non-solicitation agreement, or that we or these individuals have, inadvertently or otherwise, used or disclosed the alleged trade secrets or other proprietary information of a former employer or competitor or other party. Litigation may be necessary to defend against these claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and could be a distraction to management. If our defenses to these claims fail, in addition to requiring us to pay monetary damages, a court could prohibit us from using technologies or features that are essential to vidutolimod and future product candidates, if such technologies or features are found to incorporate or be derived from the trade secrets or other proprietary information of the former employers, competitors or other parties. An inability to incorporate such technologies or features would have a material adverse effect on our business, and may prevent us from successfully commercializing vidutolimod and future product candidates. In addition, we may lose valuable intellectual property rights or personnel as a result of such claims. Moreover, any such litigation or the threat thereof may adversely affect our ability to hire employees or consultants. A loss of key personnel or their work product could hamper or prevent our ability to develop and commercialize vidutolimod and future product candidates, which could have an adverse effect on our business, financial condition, results of operations, stock price and prospects.

86

If we obtain any issued patents covering our technology, such patents could be found invalid or unenforceable if challenged in court or before the USPTO or comparable foreign regulatory authority.

If we or one of our licensing partners initiate legal proceedings against a third party to enforce a patent covering any of our technology, the defendant could counterclaim that the patent covering vidutolimod and future product candidates is invalid or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity or unenforceability are commonplace, and there are numerous grounds upon which a third party can assert invalidity or unenforceability of a patent. Grounds for a validity challenge could be, among other things, an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness, or non-enablement. Grounds for an unenforceability assertion could be, among other things, an allegation that someone connected with prosecution of the patent withheld relevant information from the USPTO, or made a misleading statement, during prosecution. Third parties may also raise similar claims before administrative bodies in the United States or abroad, even outside the context of litigation. Such mechanisms include re-examination, inter partes review, post-grant review, interference proceedings, derivation proceedings and equivalent proceedings in foreign jurisdictions, such as opposition proceedings. Such proceedings could result in revocation, cancellation or amendment to our patents in such a way that they no longer cover and protect vidutolimod and future product candidates. The outcome following legal assertions of invalidity and unenforceability is unpredictable. For example, with respect to the validity of our licensed patents or any patents we obtain in the future, we cannot be certain that there is no invalidating prior art of which we, our or our licensing partner’s patent counsel, and the patent examiner were unaware during prosecution. If a third party were to prevail on a legal assertion of invalidity or unenforceability, we would lose at least part, and perhaps all, of the patent protection on vidutolimod and future product candidates. Such a loss of patent protection could have a material adverse impact on our business.

Risks related to manufacturing and our reliance on third parties

We currently rely on third-party CMOs, based both in the United States and abroad, for the production of clinical supply of vidutolimod and may continue to rely on CMOs for the production of commercial supply of vidutolimod, if approved. This reliance on CMOs increases the risk that we will not have sufficient quantities of such materials, product candidates, or any therapies that we may develop and commercialize, or that such supply will not be available to us at an acceptable cost, which could delay, prevent, or impair our development or commercialization efforts.

We currently have no plans to build our own clinical or commercial scale manufacturing capabilities. Instead, we expect to rely on third parties for the manufacture of our product candidates and related raw materials for future pre-clinical and clinical development, as well as for commercial manufacture if any of our product candidates receive marketing approval. We have entered into an arrangement with a number of third-party CMOs as part of our clinical development for vidutolimod. These CMOs provide drug substance intermediate and drug product that is subsequently labeled, packaged and distributed to our CROs. We may also enter into agreements with additional companies for the supply of substances for use in the development of vidutolimod or any future product candidates or for the manufacture of such product candidates.

We or our third-party suppliers or manufacturers may encounter shortages in the raw materials or active pharmaceutical ingredient (“API”) necessary to produce vidutolimod and future product candidates we may develop in the quantities needed for our clinical trials or, if vidutolimod or any future product candidates we may develop are approved, in sufficient quantities for commercialization or to meet an increase in demand, as a result of capacity constraints or delays or disruptions in the market for the raw materials or API, including shortages caused by the purchase of such raw materials or API by our competitors or others. Even if raw materials or API are available, we may be unable to obtain sufficient quantities at an acceptable cost or quality. The failure by us or our third-party suppliers or manufacturers to obtain the raw materials or API necessary to manufacture sufficient quantities of vidutolimod or any future product candidates we may develop could delay, prevent or impair our development efforts and may have a material adverse effect on our business.

87

The facilities used by third-party manufacturers to manufacture vidutolimod or any future product candidates must be authorized by the FDA pursuant to inspections that will be conducted after we submit a BLA to the FDA. We do not control the manufacturing process of, and are completely dependent on, third-party manufacturers for compliance with cGMP requirements for manufacture of drug products and other laws and regulations. If these third-party manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or others, they will not be able to secure and maintain regulatory approval for their manufacturing facilities. Some of our contract manufacturers may not have produced a commercially-approved product and therefore may not have obtained the requisite FDA approvals to do so. In addition, we have no control over the ability of third-party manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If the FDA or a comparable foreign regulatory authority does not approve these facilities for the manufacture of our product candidates or if it withdraws any such approval in the future, we may need to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our product candidates, if approved.

Finding new CMOs or third-party suppliers involves additional cost and requires our management’s time and focus. In addition, there is typically a transition period when a new CMO commences work. Although we generally have not, and do not intend to, begin a clinical trial unless we believe we have on hand, or will be able to obtain, a sufficient supply of our product candidates to complete the clinical trial, any significant delay in the supply of our product candidates or the raw materials needed to produce our product candidates, could considerably delay conducting our clinical trials and potential regulatory approval of our product candidates. Additionally, any changes implemented by a new CMO could delay completion of clinical trials, require the conduct of bridging clinical trials or studies, require the repetition of one or more clinical trials, increase clinical trial costs, delay approval of vidutolimod and future product candidates and jeopardize our ability to commence product sales and generate revenue.

If any CMO with whom we contract fails to perform its obligations, we may be forced to manufacture the materials ourselves, for which we may not have the capabilities or resources, or enter into an agreement with a different CMO, which we may not be able to do on reasonable terms, if at all. In either scenario, our clinical trials or commercial supply could be delayed significantly as we establish alternative supply sources. In some cases, the technical skills required to manufacture our products or product candidates may be unique or proprietary to the original CMO and we may have difficulty, or there may be contractual restrictions prohibiting us from, transferring such skills to a back-up or alternate supplier, or we may be unable to transfer such skills at all. In addition, if we are required to change CMOs for any reason, we will be required to verify that the new CMO maintains facilities and procedures that comply with quality standards and with all applicable regulations. We will also need to verify, such as through a manufacturing comparability study, that any new manufacturing process will produce our product candidate according to the specifications previously submitted to or approved by the FDA or another regulatory authority. The delays associated with the verification of a new CMO could negatively affect our ability to develop product candidates or commercialize our products in a timely manner or within budget. Furthermore, a CMO may possess technology related to the manufacture of our product candidate that such CMO owns independently. This would increase our reliance on such CMO or require us to obtain a license from such CMO in order to have another CMO manufacture our product candidates or products. In addition, in the case of CMOs that supply our product candidates, changes in manufacturers often involve changes in manufacturing procedures and processes, which could require that we conduct bridging studies between our prior clinical supply used in our clinical trials and that of any new manufacturer. We may be unsuccessful in demonstrating the comparability of clinical supplies which could require the conduct of additional clinical trials.

As part of their manufacture of our product candidates, our CMOs and third-party suppliers are expected to comply with and respect the intellectual property and proprietary rights of others. If a CMO or third-party supplier fails to acquire the proper licenses or otherwise infringes, misappropriates or otherwise violates the intellectual property or proprietary rights of others in the course of providing services to us, we may have to find alternative CMOs or third-party suppliers or defend against applicable claims, either of which would

88

significantly impact our ability to develop, obtain regulatory approval for or commercialize our product candidates, if approved.

Our failure, or the failure of our third-party manufacturers, to comply with applicable regulations could result in sanctions being imposed on us, including clinical holds, fines, injunctions, civil penalties, delays, suspension or withdrawal of approvals, seizures or recalls of product candidates or products, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect supplies of our products. In addition, we may be unable to establish any agreements with third-party manufacturers or to do so on acceptable terms.

Even if we are able to establish agreements with third-party manufacturers, reliance on third-party manufacturers entails additional risks, including:

• failure of third-party manufacturers to comply with regulatory requirements and maintain quality assurance;

• breach of the manufacturing agreement by the third party;

• failure to manufacture our product according to our specifications;

• failure to manufacture our product according to our schedule or at all;

• production difficulties caused by unforeseen events that may delay the availability of one or more of the necessary raw materials or delay the manufacture of vidutolimod or any future product candidates for use in clinical trials or for commercial supply, including as a result of the COVID-19 pandemic;

• misappropriation of our proprietary information, including our trade secrets and know-how; and

• termination or nonrenewal of the agreement by the third party at a time that is costly or inconvenient for us.

Vidutolimod and any other product candidates that we may develop may compete with other product candidates and products for access to manufacturing facilities. Any performance failure on the part of our existing or future manufacturers could delay clinical development or marketing approval, and any related remedial measures may be costly or time-consuming to implement. We do not currently have arrangements in place for redundant supply or a second source for all required raw materials used in the manufacture of our product candidates. If our current third-party manufacturers cannot perform as agreed, we may be required to replace such manufacturers and we may be unable to replace them on a timely basis or at all. Our current and anticipated future dependence upon others for the manufacture of vidutolimod or any other future product candidates or products may adversely affect our future profit margins and our ability to commercialize any products that receive marketing approval on a timely and competitive basis.

We rely, and expect to continue to rely, on third parties to conduct, supervise, and monitor our preclinical studies and clinical trials. If those third parties do not perform satisfactorily, including failing to meet deadlines for the completion of such trials or failing to comply with regulatory requirements, we may be unable to obtain regulatory approval for vidutolimod or any future product candidates.

We rely on third-party CROs, study sites, clinical investigators and others to conduct, supervise, and monitor our preclinical studies and clinical trials for vidutolimod and future product candidates. We expect to continue to rely on third parties, such as CROs, clinical data management organizations, medical institutions, and clinical investigators, to conduct our preclinical studies and clinical trials. Although we have agreements governing their activities, we have limited influence over their actual performance and control only certain aspects of their activities. The failure of these third parties to successfully carry out their contractual duties or meet expected deadlines, including as a result of the impact of the ongoing COVID-19 pandemic, could substantially harm our business because we may be delayed in completing or unable to complete the studies required to support future approval of vidutolimod and future product candidates, or we may not obtain marketing approval for, or

89

commercialize, vidutolimod and future product candidates in a timely manner or at all. Moreover, these agreements might terminate for a variety of reasons, including a failure to perform by the third parties. If we need to enter into alternative arrangements our product development activities would be delayed and our business, financial condition, results of operations, stock price and prospects may be materially harmed.

Our reliance on these third parties for development activities reduces our control over these activities. Nevertheless, we are responsible for ensuring that each of our studies is conducted in accordance with the applicable protocol, legal, regulatory, and scientific standards and our reliance on third parties does not relieve us of our regulatory responsibilities. For example, we will remain responsible for ensuring that each of our trials is conducted in accordance with the general investigational plan and protocols for the trial. We must also ensure that our preclinical trials are conducted in accordance with the FDA’s GLP regulations, as appropriate. Moreover, the FDA and comparable foreign regulatory authorities require us to comply with GCPs for conducting, recording, and reporting the results of clinical trials to assure that data and reported results are credible and accurate and that the rights, integrity, and confidentiality of trial participants are protected. Regulatory authorities enforce these requirements through periodic inspections of trial sponsors, clinical investigators, and trial sites. If we or any of our third parties fail to comply with applicable GCPs or other regulatory requirements, we or they may be subject to enforcement or other legal actions, the data generated in our trials may be deemed unreliable and the FDA or comparable foreign regulatory authorities may require us to perform additional studies.

In addition, we will be required to report certain financial interests of our third-party investigators if these relationships exceed certain financial thresholds or meet other criteria. The FDA or comparable foreign regulatory authorities may question the integrity of the data from those clinical trials conducted by investigators who may have conflicts of interest.

We cannot assure you that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our trials complies with the applicable regulatory requirements. In addition, our clinical trials must be conducted with product candidates that were produced under cGMP regulations. Failure to comply with these regulations may require us to repeat clinical trials, which would delay the regulatory approval process. We also are required to register certain clinical trials and post the results of certain completed clinical trials on a government-sponsored database, ClinicalTrials.gov, within specified timeframes. Failure to do so can result in enforcement actions and adverse publicity.

The third parties with which we work may also have relationships with other entities, some of which may be our competitors, for whom they may also be conducting trials or other therapeutic development activities that could harm our competitive position. In addition, such third parties are not our employees, and except for remedies available to us under our agreements with such third parties we cannot control whether or not they devote sufficient time and resources to our ongoing clinical, non-clinical, and preclinical programs. If these third parties do not successfully carry out their contractual duties, meet expected deadlines or conduct our preclinical studies or clinical trials in accordance with regulatory requirements or our stated protocols, if these parties are adversely impacted by the ongoing COVID-19 pandemic limiting or materially affecting their ability to carry out their contractual duties, if they need to be replaced or if the quality or accuracy of the data they obtain is compromised due to the failure to adhere to our protocols, regulatory requirements or for other reasons, our trials may be repeated, extended, delayed, or terminated; we may not be able to obtain, or may be delayed in obtaining, marketing approvals for vidutolimod and future product candidates; we may not be able to, or may be delayed in our efforts to, successfully commercialize vidutolimod and future product candidates; or we or they may be subject to regulatory enforcement actions. As a result, our results of operations and the commercial prospects for vidutolimod and future product candidates would be harmed, our costs could increase and our ability to generate revenues could be delayed. To the extent we are unable to successfully identify and manage the performance of third-party service providers in the future, our business, financial condition, results of operations, stock price and prospects may be materially harmed.

90

If any of our relationships with these third parties terminate, we may not be able to enter into arrangements with alternative providers or to do so on commercially reasonable terms. Switching or adding additional third parties involves additional cost and requires management’s time and focus. In addition, there is a natural transition period when a new third party commences work. As a result, delays could occur, which could compromise our ability to meet our desired development timelines.

We also rely on other third parties to store and distribute our products for the clinical trials that we conduct. Any performance failure on the part of our distributors could delay clinical development, marketing approval, or commercialization of vidutolimod and future product candidates, which could result in additional losses and deprive us of potential product revenue.

Our collaboration agreements with any future third-parties may not be successful, which could adversely affect our ability to develop and commercialize vidutolimod or any future product candidates.

We may in the future seek collaboration arrangements with other parties for the development or commercialization of vidutolimod or any future product candidates. The success of existing or any future collaboration arrangements may depend on the efforts and activities of our collaborators. Collaborators generally have significant discretion in determining the efforts and resources that they will apply to these arrangements. Disagreements between parties to a collaboration arrangement regarding clinical development and commercialization matters can lead to delays in the development process or commercializing the applicable product candidate and, in some cases, termination of the collaboration arrangement. These disagreements can be difficult to resolve if neither of the parties has final decision making authority.

Collaborations with biopharmaceutical companies and other third parties often are terminated or allowed to expire by the other party. Any such termination or expiration could adversely affect us financially and could harm our business reputation.

Any future collaborations we might enter into may pose a number of risks, including the following:

• collaborators may not perform their obligations as expected;

• collaborators may not pursue development and commercialization of any product candidates that achieve regulatory approval or may elect not to continue or renew development or commercialization programs based on clinical trial results, changes in the collaborators’ strategic focus or available funding, or external factors, such as an acquisition, that divert resources or create competing priorities;

• collaborators may delay clinical trials, provide insufficient funding for a clinical trial program, stop a clinical trial or abandon a product candidate, repeat or conduct new clinical trials or require a new formulation of a product candidate for clinical testing;

• collaborators could fail to make timely regulatory submissions for a product candidate;

• collaborators may control the public release of information regarding the developments, and we may not be able to make announcements or data presentations on a schedule favorable to us;

• collaborators may not comply with all applicable regulatory requirements or may fail to report safety data in accordance with all applicable regulatory requirements, which could subject them or us to regulatory enforcement actions;

• collaborators could independently develop, or develop with third parties, products that compete directly or indirectly with our products or product candidates if the collaborators believe that competitive products are more likely to be successfully developed or can be commercialized under terms that are more economically attractive than ours;

• product candidates discovered in collaboration with us may be viewed by our collaborators as competitive with their own product candidates or products, which may cause collaborators to cease to devote resources to the commercialization of vidutolimod and future product candidates;

91

• a collaborator with marketing and distribution rights to vidutolimod or any future product candidates that achieve regulatory approval may not commit sufficient resources to the marketing and distribution of such product candidate or product;

• disagreements with collaborators, including disagreements over proprietary rights, contract interpretation or the preferred course of development, might cause delays or termination of the research, development or commercialization of product candidates, might lead to additional responsibilities for us with respect to product candidates or might result in litigation or arbitration, any of which would be time consuming and expensive;

• collaborators may not properly maintain or defend our intellectual property rights or may use our proprietary information in such a way as to invite litigation that could jeopardize or invalidate our intellectual property or proprietary information or expose us to potential litigation; and

• collaborators may infringe the intellectual property rights of third parties, which may expose us to litigation and potential liability.

If any collaborations we might enter into in the future do not result in the successful development and commercialization of products or if one of our collaborators subsequently terminates its agreement with us, we may not receive any future research funding or milestone or royalty payments under such potential future collaboration. If we do not receive the funding we expect under the agreements, our development of vidutolimod and future product candidates could be delayed and we may need additional resources to develop vidutolimod and future product candidates and our product platform.

Additionally, if any future collaborator of ours is involved in a business combination, the collaborator might deemphasize or terminate development or commercialization of any product candidate licensed to it by us. If one of our collaborators terminates its agreement with us, we may find it more difficult to attract new collaborators and our reputation in the business and financial communities could be adversely affected.

We face significant competition in seeking appropriate collaborators. Our ability to reach a definitive agreement for any collaboration will depend, among other things, upon our assessment of the collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors.

If we are unable to reach agreements with suitable collaborators on a timely basis, on acceptable terms, or at all, we may have to curtail the development of a product candidate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or reduce the scope of any sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to fund and undertake development or commercialization activities on our own, we may need to obtain additional expertise and additional capital, which may not be available to us on acceptable terms, or at all. If we fail to enter into collaborations and do not have sufficient funds or expertise to undertake the necessary development and commercialization activities, we may not be able to further develop vidutolimod and future product candidates or bring them to market or continue to develop our product platform and our business may be materially and adversely affected.

If we materially breach or default on our current or future license agreements, the licensor party to such agreement may have the right to terminate the license agreement, which termination may materially harm our business.

Our commercial success will depend in part on the maintenance of our license agreements. Currently, we are a party to the Kuros License Agreement, and we expect to enter into additional license agreements in the future. The Kuros License Agreement imposes, and we expect that future license agreements will impose, various diligence, milestone payment, royalty and other obligations on us. For example, under the Kuros License

92

Agreement, we are required to use commercially reasonable diligence to develop and commercialize a product and to satisfy specified payment obligations. If we fail to comply with our obligations under the Kuros License Agreement or any future license agreements with any party, or we are subject to a bankruptcy, the licensor may have the right to terminate the license, in which event we would not be able to market products covered by the license. The Kuros License Agreement further provides Kuros with a right to terminate the license agreements for our material breach or default under the agreement, including the failure to make any required milestone or other payments. Should Kuros exercise such a termination right, we would lose our right to the intellectual property under the license agreement, and such loss may materially harm our business. Moreover, the termination of the Kuros License Agreement or any reduction in our collaboration with Kuros may delay or impair our development efforts.

Risks related to our operations

Our future success depends on our ability to retain key executives and to attract, retain and motivate qualified personnel.

We are highly dependent on the principal members of our management, scientific and clinical team. Although we have entered into employment agreements with our executive officers, each of them may terminate their employment with us at any time. In addition, we rely on consultants and advisors, including scientific and clinical advisors, to assist us in formulating our research and development and commercialization strategy. Our consultants and advisors may be employed by employers other than us and may have commitments under consulting or advisory contracts with other entities that may limit their availability to us. If we are unable to continue to attract and retain high quality personnel, our ability to pursue our growth strategy will be limited.

Recruiting and retaining qualified scientific, clinical, manufacturing and sales and marketing personnel will also be critical to our success. The loss of the services of our executive officers or other key employees could impede the achievement of our research, development and commercialization objectives and seriously harm our ability to successfully implement our business strategy. Furthermore, replacing executive officers and key employees may be difficult and may take an extended period of time because of the limited number of individuals in our industry with the breadth of skills and experience required to successfully develop, gain regulatory approval of and commercialize drugs. Competition to hire from this limited pool is intense, and we may be unable to hire, train, retain or motivate these key personnel on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies for similar personnel. We also experience competition for the hiring of scientific and clinical personnel from universities and research institutions. Failure to succeed in our clinical trials may make it more challenging to recruit and retain qualified scientific and other personnel. Failure to raise sufficient additional capital may also make it more challenging to recruit and retain qualified personnel.

On October 28, 2021, our Board of Directors, or our Board, accepted the resignation of Barry Labinger as our President and Chief Executive Officer. Our Board appointed Alan Fuhrman, previously Chairman of our Audit Committee, as Interim President and Chief Executive Officer. Effective March 1, 2022, Alan Bash replaced Alan Fuhrman as the Company’s President and Chief Executive Officer. As a result of the recent appointment of Mr. Bash, our senior management team has limited experience working together as a group. This lack of shared experience could negatively impact our senior management team’s ability to quickly and efficiently respond to problems and effectively manage our business. If our management team is not able to work together as a group, our results of operations may suffer and our business may be harmed.

We will need to develop and expand our company, and we may encounter difficulties in managing this development and expansion, which could disrupt our operations.

As of December 31, 2021, we had 30 full-time employees, and we expect to increase our number of employees and the scope of our operations. To manage our anticipated development and expansion, we must continue to implement and improve our managerial, operational and financial systems, expand our facilities and continue to

93

recruit and train additional qualified personnel. Also, our management may need to divert a disproportionate amount of its attention away from its day-to-day activities and devote a substantial amount of time to managing these development activities. Due to our limited resources, we may not be able to effectively manage the expansion of our operations or recruit and train additional qualified personnel. The physical or geographic expansion of our operations may lead to significant costs and may divert financial resources from other projects, such as the development of vidutolimod and future product candidates. If our management is unable to effectively manage our expected development and expansion, our expenses may increase more than expected, our ability to generate or increase our revenue could be reduced and we may not be able to implement our business strategy. Our future financial performance and our ability to commercialize vidutolimod and future product candidates, if approved, and to compete effectively will depend, in part, on our ability to effectively manage the future development and expansion of our company.

If we engage in future acquisitions or strategic partnerships, our capital requirements may increase, our stockholders may be diluted, we may incur debt or assume contingent liabilities, and we may be subject to other risks.

We may evaluate various acquisitions and strategic partnerships, including licensing or acquiring complementary products, intellectual property rights, technologies, or businesses. Any potential acquisition or strategic partnership may entail numerous risks, including:

• increased operating expenses and cash requirements;

• the assumption of additional indebtedness or contingent liabilities;

• the issuance of our equity securities;

• assimilation of operations, intellectual property and products of an acquired company, including difficulties associated with integrating new personnel;

• the diversion of our management’s attention from our existing product programs and initiatives in pursuing such a strategic merger or acquisition;

• retention of key employees, the loss of key personnel, and uncertainties in our ability to maintain key business relationships;

• risks and uncertainties associated with the other party to such a transaction, including the prospects of that party, their regulatory compliance status, and their existing products or product candidates and marketing approvals; and

• our inability to generate revenue from acquired technology or products sufficient to meet our objectives in undertaking the acquisition or even to offset the associated acquisition and maintenance costs.

In addition, if we undertake acquisitions, we may issue dilutive securities, assume or incur debt obligations, incur large one-time expenses and acquire intangible assets that could result in significant future amortization expense. Moreover, we may not be able to locate suitable acquisition opportunities and this inability could impair our ability to grow or obtain access to technology or products that may be important to the development of our business. Any of the foregoing may materially harm our business, financial condition, results of operations, stock price and prospects.

If we fail to maintain proper and effective internal controls over financial reporting our ability to produce accurate and timely financial statements could be impaired.

We are required to maintain internal controls over financial reporting. Commencing this fiscal year, we must perform system and process design evaluation and testing of the effectiveness of our internal controls over financial reporting to allow management to report on the effectiveness of our internal controls over financial reporting in our Form 10-K filing for that year, as required by Section 404 of the Sarbanes-Oxley Act of 2002

94

(“Sarbanes-Oxley Act”). This will require that we incur substantial additional professional fees and internal costs to expand our accounting and finance functions and that we expend significant management efforts. We have not yet been required to test our internal controls within a specified period and, as a result, we may experience difficulty in meeting these reporting requirements in a timely manner. In addition, in connection with the audits of our consolidated financial statements as of and for the years ended December 31, 2019, we identified a material weakness in our internal control over financial reporting. See “—We previously identified a material weakness in our internal control over financial reporting. If our internal control over financial reporting is not effective, we may not be able to accurately report our financial results or file our periodic reports in a timely manner, which may cause adverse effects on our business and may cause investors to lose confidence in our reported financial information and may lead to a decline in our stock price.” In addition, our independent registered public accounting firm will be required to provide an attestation report on our internal control over financial reporting. However, while we remain an emerging growth company, we will not be required to provide the attestation report.

If we are not able to comply with the requirements of Section 404 of the Sarbanes-Oxley Act in a timely manner or we are unable to maintain proper and effective internal controls over financial reporting we may not be able to produce timely and accurate financial statements. As a result, our investors could lose confidence in our reported financial information, the market price of our stock could decline and we could be subject to sanctions or investigations by the SEC or other regulatory authorities.

We believe that any internal controls and procedures, no matter how well-conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. We may discover weaknesses in our system of internal financial and accounting controls and procedures that could result in a material misstatement of our consolidated financial statements. Our internal control over financial reporting will not prevent or detect all errors and all fraud. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud will be detected.

These inherent limitations include the realities that judgments in decision-making can be faulty, and that breakdowns can occur because of simple error or mistake. For example, our directors or executive officers could inadvertently fail to disclose a new relationship or arrangement causing us to fail to make a required related party transaction disclosure. Additionally, controls can be circumvented by the individual acts of some persons, by collusion of two or more people or by an unauthorized override of the controls. Accordingly, because of the inherent limitations in our control system, misstatements due to error or fraud may occur and not be detected.

Our disclosure controls and procedures may not prevent or detect all errors or acts of fraud.

As a public company, we are subject to the periodic reporting requirements of the Exchange Act of 1934, as amended (the “Exchange Act”). We must design our disclosure controls and procedures to reasonably assure that information we must disclose in reports we file or submit under the Exchange Act is accumulated and communicated to management, and recorded, processed, summarized and reported within the time periods specified in the rules and forms of the SEC. Decision-making can be faulty and breakdowns can occur because of simple error or mistake. For example, our directors or executive officers could inadvertently fail to disclose a new relationship or arrangement causing us to fail to make a required related party transaction disclosure. Additionally, controls can be circumvented by the individual acts of some persons, by collusion of two or more people or by an unauthorized override of the controls. Accordingly, because of the inherent limitations in our control system, misstatements due to error or fraud may occur and not be detected.

95

We previously identified a material weakness in our internal control over financial reporting. If our internal control over financial reporting is not effective, we may not be able to accurately report our financial results or file our periodic reports in a timely manner, which may cause adverse effects on our business and may cause investors to lose confidence in our reported financial information and may lead to a decline in our stock price.

Effective internal control over financial reporting is necessary for us to provide reliable financial reports in a timely manner. In connection with the audit of our financial statement for the years ended December 31, 2019, we concluded that there was a material weakness in our internal control over financial reporting. As of December 31, 2020, we concluded that this material weakness had been remediated, but there can be no assurance that we will not identify future material weaknesses or reportable conditions.

The material weaknesses we identified related to the maintenance of an effective control environment commensurate with our financial reporting requirements. Specifically, we lacked sufficient personnel to maintain effective segregation of duties in the processing and recording of financial transactions.

To remediate this weakness, we expanded our finance organization to allow for the segregation of duties in the processing and recording of financial transaction by hiring a full-time chief financial officer and accounting manager to augment our accounting staff and to provide more resources for control environment. We also redesigned our processes and related controls to maintain effective segregation of duties in the processing and recording of financial transactions.

If we identify any future significant deficiencies or material weaknesses, the accuracy and timing of our financial reporting may be adversely affected, a material misstatement in our consolidated financial statements could occur, we may be unable to maintain compliance with securities law requirements regarding timely filing of periodic reports, which may adversely affect our business and our stock price may decline as a result.

Nevertheless, we will be required to expend significant time and resources to further improve our internal controls over financial reporting, including by further expanding our finance and accounting staff to meet the demands that are placed upon us as a public company, including the requirements of the Sarbanes-Oxley Act. If we fail to adequately staff our accounting and finance function, or fail to maintain adequate internal control over financial reporting, any new or recurring material weaknesses could prevent our management from concluding our internal control over financial reporting is effective and impair our ability to prevent material misstatements in our consolidated financial statements, which could cause our business to suffer.

Risks related to our common stock

The price of our common stock has been and may continue to be volatile and the value of an investment in our common stock may decline.

Our stock price is and is likely to continue to be highly volatile. Between January 1, 2022 and March 25, 2022, the trading price of our common stock ranged between a low sales price of $2.00 and a high sales price of $3.49. The stock market in general and the market for biopharmaceutical companies in particular have experienced periods of extreme volatility that has often been unrelated to the operating performance of particular companies. As a result of this volatility, a holder may not be able to sell our common stock at or above the price at which such holder acquired shares of our common stock. The market price for our common stock may be influenced by many factors, including:

• the success of competitive drugs or technologies;

• results of clinical trials of vidutolimod and future product candidates or those of our competitors, including interim or topline results;

• regulatory or legal developments in the United States and other countries;

96

• the regulatory status of our product candidates;

• failure of any of our product candidates, if approved, to achieve commercial success;

• developments or disputes concerning patent applications, issued patents or other proprietary rights;

• the recruitment or departure of key personnel;

• the time it takes and level of expenses related to any of vidutolimod and future product candidates or clinical development programs;

• the results of our efforts to discover, develop, acquire or in-license future product candidates or drugs;

• actual or anticipated changes in estimates as to financial results, development timelines or recommendations by securities analysts;

• variations in our financial results or those of companies that are perceived to be similar to us;

• changes in the structure of healthcare payment systems;

• market conditions in the pharmaceutical and biotechnology sectors;

• the impact of the ongoing COVID-19 pandemic on us or on the U.S. and global economies and global equity markets;

• general economic, industry and market conditions; and

• the other factors described in this “Risk Factors” section.

Anti-takeover provisions under our charter documents and Delaware law could delay or prevent a change of control, which could limit the market price of our common stock and may prevent or frustrate attempts by our stockholders to replace or remove our current management.

Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that could delay or prevent a change of control of our company or changes in our board of directors that our stockholders might consider favorable. Some of these provisions include:

• a board of directors divided into three classes serving staggered three-year terms, such that not all members of the board will be elected at one time;

• a prohibition on stockholder action through written consent, which requires that all stockholder actions be taken at a meeting of our stockholders;

• a requirement that special meetings of stockholders be called only by the board of directors acting pursuant to a resolution approved by the affirmative vote of a majority of the directors then in office;

• advance notice requirements for stockholder proposals and nominations for election to our board of directors;

• a requirement that no member of our board of directors may be removed from office by our stockholders except for cause and, in addition to any other vote required by law, upon the approval of not less than two-thirds of all outstanding shares of our voting stock then entitled to vote in the election of directors;

• a requirement of approval of not less than two-thirds of all outstanding shares of our voting stock to amend any bylaws by stockholder action or to amend specific provisions of our certificate of incorporation; and

• the authority of the board of directors to issue preferred stock on terms determined by the board of directors without stockholder approval and which preferred stock may include rights superior to the rights of the holders of common stock.

97

In addition, because we are incorporated in Delaware, we are governed by the provisions of Section 203 of the Delaware General Corporate Law, which may prohibit certain business combinations with stockholders owning 15% or more of our outstanding voting stock. These anti-takeover provisions and other provisions in our amended and restated certificate of incorporation and amended and restated bylaws could make it more difficult for stockholders or potential acquirers to obtain control of our board of directors or initiate actions that are opposed by the then-current board of directors and could also delay or impede a merger, tender offer, or proxy contest involving our company. These provisions could also discourage proxy contests and make it more difficult for you and other stockholders to elect directors of your choosing or cause us to take other corporate actions you desire. Any delay or prevention of a change of control transaction or changes in our board of directors could cause the market price of our common stock to decline.

Our amended and restated bylaws designate a certain court as the sole and exclusive forum for certain types of actions and proceedings that may be initiated by our stockholders, which could limit our stockholders’ ability to obtain a favorable judicial forum for disputes with us or our directors, officers, or employees.

Pursuant to our amended and restated bylaws, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware is the sole and exclusive forum for any state law claims for (i) any derivative action or proceeding brought on our behalf, (ii) any action asserting a claim of breach of fiduciary duty owed by any of our directors, officers, employees or agents to us or our stockholders, (iii) any action asserting a claim arising pursuant to any provision of the Delaware General Corporation Law, our amended and restated certificate of incorporation and our amended and restated bylaws, (iv) any action to interpret, apply, enforce or determine the validity of our certificate of incorporation or by-laws or (v) any action asserting a claim that is governed by the internal affairs doctrine, in each case subject to the Court of Chancery having personal jurisdiction over the indispensable parties named as defendants therein (the “Delaware Forum Provision”). The Delaware Forum Provision will not apply to any causes of action arising under the Securities Act of 1933, as amended (the “Securities Act”) or the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. Unless we consent in writing to the selection of an alternate forum, the United Stated District Court for the District of Massachusetts shall be the sole and exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act (the “Federal Forum Provision”), as our principal office is located in Cambridge, Massachusetts. In addition, our amended and restated bylaws provide that any person or entity purchasing or otherwise acquiring any interest in our shares of common stock is deemed to have notice of and consented to the Delaware Forum Provision and the Federal Forum Provision; provided, however, that stockholders cannot and will not be deemed to have waived our compliance with the federal securities laws and the rules and regulations thereunder.

The Delaware Forum Provision and the Federal Forum Provision may impose additional litigation costs on stockholders who assert the provision is not enforceable and may impose more general additional litigation costs in pursuing any such claims, particularly if the stockholders do not reside in or near the State of Delaware or the Commonwealth of Massachusetts. In addition, these forum selection clauses in our bylaws may limit our stockholders’ ability to bring a claim in a judicial forum that they find favorable for disputes with us or our directors, officers or employees, which may discourage such lawsuits against us and our directors, officers and employees even though an action, if successful, might benefit our stockholders. Moreover, while the Delaware Supreme Court ruled in March 2020 that federal forum selection provisions purporting to require claims under the Securities Act be brought in federal court were “facially valid” under Delaware law, there is uncertainty as to whether other courts will enforce our Federal Forum Provision. If the Federal Forum Provision is found to be unenforceable, we may incur additional costs associated with resolving such matters. The Federal Forum Provision may also impose additional litigation costs on stockholders who assert that the provision is not enforceable or invalid. The Federal Forum Provision may also impose additional litigation costs on stockholders who assert the provision is not enforceable or invalid. The Court of Chancery of the State of Delaware may also reach different judgments or results than would other courts, including courts where a stockholder considering an action may be located or would otherwise choose to bring the action, and such judgments may be more or less favorable to us than our stockholders.

98

General risk factors

We will continue to incur increased costs as a result of operating as a public company, and our management will be required to devote substantial time to compliance initiatives.

As a relatively newly public company, we have been and will continue to incur significant legal, accounting, and other expenses that we did not incur as a private company. We are subject to the reporting requirements of the Exchange Act, which require, among other things, that we file with the SEC annual, quarterly, and current reports with respect to our business and financial condition. In addition, the Sarbanes-Oxley Act, as well as rules adopted by the SEC and Nasdaq to implement provisions of the Sarbanes-Oxley Act, impose significant requirements on public companies, including requiring establishment and maintenance of effective disclosure and financial controls and changes in corporate governance practices. Further, in July 2010, the Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”) was enacted. There are significant corporate governance and executive compensation related provisions in the Dodd-Frank Act that required the SEC to adopt additional rules and regulations in these areas, such as “say on pay” and proxy access. The Jumpstart Our Business Startups Act (“JOBS Act”) permits emerging growth companies and smaller reporting companies like us to implement many of these requirements over a longer period and up to five years from the pricing of our initial public offering (“IPO”). We intend to take advantage of this extended time period for compliance, but cannot guarantee that we will not be required to implement these requirements sooner than budgeted or planned and thereby incur unexpected expenses. Stockholder activism, the current political and economic environment, and the high levels of government intervention and regulatory reform may lead to substantial new regulations and disclosure obligations, which may lead to additional compliance costs and impact the manner in which we operate our business in ways we cannot currently anticipate.

We expect the rules and regulations applicable to public companies to substantially increase our legal and financial compliance costs and to make some activities more time-consuming and costly. If these requirements divert the attention of our management and personnel from other business concerns, they could have a material adverse effect on our business, financial condition, and results of operations. The increased costs will increase our net loss and may require us to reduce costs in other areas of our business. For example, we expect these rules and regulations to make it more difficult and more expensive for us to obtain director and officer liability insurance and we may be required to incur substantial costs to maintain the same or similar coverage. We cannot predict or estimate the amount or timing of additional costs we may incur to respond to these requirements. The impact of these requirements could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors, our board committees, or as executive officers.

If securities analysts do not continue to publish research or reports about our business or if they publish negative evaluations of our stock, the price of our stock could decline.

The trading market for our common stock relies in part on the research and reports that industry or financial analysts publish about us or our business. If one or more of the analysts covering our business downgrade their evaluations of our stock, the price of our stock could decline. If one or more of these analysts cease to cover our stock, we could lose visibility in the market for our stock, which in turn could cause our stock price to decline. If our public float stays below $75 million, the risk that analysts cease to cover our stock may increase.

We are an emerging growth company and a smaller reporting company, and we cannot be certain if the reduced reporting requirements applicable to emerging growth companies and smaller reporting companies will make our common stock less attractive to investors.

We are an emerging growth company, as defined in the JOBS Act. For as long as we continue to be an emerging growth company, we may take advantage of exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies, including not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements, and exemptions from the

99

requirements of holding nonbinding advisory votes on executive compensation and stockholder approval of any golden parachute payments not previously approved. We will remain an emerging growth company until the earlier of (i) the last day of the fiscal year (a) following the fifth anniversary of the closing of our IPO, (b) in which we have total annual gross revenue of at least $1.07 billion or (c) in which we are deemed to be a large accelerated filer, which requires the market value of our common stock that is held by non-affiliates to exceed $700 million as of the prior June 30th , and (ii) the date on which we have issued more than $1 billion in non-convertible debt during the prior three-year period.

Under the JOBS Act, emerging growth companies can also delay adopting new or revised accounting standards until such time as those standards apply to private companies. We have elected to not “opt out” of this exemption from complying with new or revised accounting standards and, therefore, we will adopt new or revised accounting standards at the time private companies adopt the new or revised accounting standard and will do so until such time that we either (i) irrevocably elect to “opt out” of such extended transition period or (ii) no longer qualify as an emerging growth company.

Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company,” which would allow us to continue to take advantage of many of the same exemptions from disclosure requirements, including not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act and reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements. We cannot predict if investors will find our common stock less attractive because we may rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile.

Because we do not anticipate paying any cash dividends on our capital stock in the foreseeable future, capital appreciation, if any, will be your sole source of gain.

We have never declared or paid cash dividends on our capital stock. We currently intend to retain all of our future earnings, if any, to finance the growth and development of our business. As a result, capital appreciation, if any, of our common stock will be your sole source of gain for the foreseeable future.

Changes in tax law could adversely affect our business and financial condition.

The rules dealing with U.S. federal, state and local income taxation are constantly under review by persons involved in the legislative process and by the Internal Revenue Service and the U.S. Treasury Department. Changes to tax laws (which changes may have retroactive application) could adversely affect us or holders of our common stock. In recent years, many such changes have been made and changes are likely to continue to occur in the future.

It cannot be predicted whether, when, in what form or with what effective dates new tax laws may be enacted, or regulations and rulings may be promulgated or issued under existing or new tax laws, which could result in an increase in our or our shareholders’ tax liability or require changes in the manner in which we operate in order to minimize or mitigate any adverse effects of changes in tax law or in the interpretation thereof.

Our ability to utilize our net operating loss carryforwards and certain other tax attributes may be limited.

As of December 31, 2021, we had U.S. federal NOL carryforwards of $169.3 million, including $138.0 million which have an indefinite carryforward period and $31.3 million which expire at various dates through 2037. As of December 31, 2021, we had state net operating loss carryforwards of $147.9 million which expire at various dates through 2041. As of December 31, 2021, we had federal and state research and development tax credit carryforwards of approximately $9.2 million available to reduce future tax liabilities, which begin to expire in 2031.

Under Sections 382 and 383 of the Code, and certain corresponding provisions of state law, a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change NOL

100

carryforwards or credits to offset future taxable income or taxes. For these purposes, an ownership change generally occurs where the aggregate stock ownership of one or more stockholders or groups of stockholders who owns at least 5% of a corporation’s stock increases its ownership by more than 50 percentage points over its lowest ownership percentage within a specified testing period. We have completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes since its formation. The results of this study indicated that the Company experienced ownership changes as defined by Section 382 of the Code. The Company has identified approximately $1.3 million of NOLs that, as a result of these restrictions, will expire unused. We may experience ownership changes in the future as a result if subsequent shifts in our stock ownership, some of which are outside our control. If finalized, Treasury Regulations currently proposed under Section 382 of the Code may further limit our ability to utilize our pre-change NOL carryforwards or credits if we undergo a future ownership change. The amount of NOLs generated in taxable years beginning after December 31, 2021 that we are permitted to deduct in any taxable year is limited to 80% of our taxable income in such, where taxable income is determined without regard to such NOL deduction itself. Our NOLs or credits may also be impaired under state law. Accordingly, due to these limitations, we may not be able to utilize a material portion of our NOLs or credits. Furthermore, our ability to utilize our NOLs or credits is conditioned upon our attaining profitability and generating U.S. federal and state taxable income. We have incurred significant net losses since our inception and anticipate that we will continue to incur significant losses for the foreseeable future; and therefore, we do not know whether or when we will generate the U.S. federal or state taxable income necessary to utilize our NOLs or credits.

Unstable market, economic and geopolitical conditions may have serious adverse consequences on our business, financial condition and stock price.

Global financial markets have in the past experienced, extreme volatility and disruptions, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. There can be no assurance that further deterioration in credit and financial markets and confidence in economic conditions will not occur. Our general business strategy and ability to raise capital may be adversely affected by any such economic downturn, volatile business environment, geopolitical instability or continued unpredictable and unstable market conditions. If the current equity and credit markets deteriorate, it may make any necessary debt or equity financing more difficult, more costly, and more dilutive. Failure to secure any necessary financing in a timely manner and on favorable terms could have a material adverse effect on our growth strategy, financial performance and stock price and could require us to delay or abandon clinical development plans. In addition, there is a risk that one or more of our current service providers, manufacturers and other third-parties may not survive these difficult economic times, which could directly affect our ability to attain our operating goals on schedule and on budget. Additionally, we have concluded that there is substantial doubt concerning our ability to continue as a going concern.

In addition, the stock markets have experienced extreme price and volume fluctuations that have affected and continue to affect the market prices of equity securities of many companies, including in connection with the ongoing COVID-19 pandemic, which resulted in decreased stock prices for many companies notwithstanding the lack of a fundamental change in their underlying business models or prospects, and more recently as a result of the conflict between Russia and Ukraine. These fluctuations have often been unrelated or disproportionate to the operating performance of those companies. Market and industry factors, including potentially worsening economic and geopolitical conditions and other adverse effects or developments relating to the ongoing COVID-19 pandemic, political, regulatory and other market conditions, may negatively affect the market price of shares of our common stock, regardless of our actual operating performance.

As of December 31, 2021, our cash, cash equivalents and available-for-sale investments were $70.9 million. While we are not aware of any downgrades, material losses, or other significant deterioration in the fair value of our cash equivalents since December 31, 2021, no assurance can be given that further deterioration of the global credit and financial markets would not negatively impact our current portfolio of cash equivalents or our ability to meet our financing objectives. Given these uncertainties, we have concluded that there is substantial doubt

101

concerning our ability to continue operations as a going concern. See “There is substantial doubt regarding our ability to continue as a going concern. We will need to raise additional funding, which may not be available on acceptable terms, or at all. Failure to obtain this necessary capital when needed may force us to delay, limit, reduce or terminate our product development efforts or other operations.”

We, or the third parties upon whom we depend, may be adversely affected by natural or other disasters, and our business continuity and disaster recovery plans may not adequately protect us from a serious disaster.

Any unplanned event, such as earthquake, flood, fire, explosion, extreme weather, medical epidemic, pandemic, power shortage, telecommunication failure or other natural or manmade accidents or incidents, including the COVID-19 pandemic, could severely disrupt our operations, and have a material adverse effect on our business, results of operations, financial condition and prospects. If a natural disaster, power outage or other event occurred that prevented us from using all or a significant portion of our headquarters, that damaged critical infrastructure, such as the manufacturing facilities of our third-party contract manufacturers, or that otherwise disrupted operations, it may be difficult or, in certain cases, impossible for us to continue our business for a substantial period of time. We plan to put disaster recovery and business continuity plans in place; however, these may prove inadequate in the event of a serious disaster or similar event. We may incur substantial expenses as a result of the limited nature of our disaster recovery and business continuity plans, which, could have a material adverse effect on our business.

Our internal computer systems, or those of our third-party CROs or other contractors or consultants, may fail or suffer security breaches, which could result in a material disruption of vidutolimod and future product candidates’ development programs.

Despite our implementation of security measures, our internal computer systems, and those of our CROs, CMOs, IT suppliers and other contractors and consultants are vulnerable to damage from computer viruses, cyber-attacks and other unauthorized access, natural disasters, terrorism, war, and telecommunication and electrical failures. If such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our development programs for vidutolimod and future product candidates. For example, the loss of clinical trial data from completed, ongoing or planned clinical trials could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. To the extent that any disruption or security breach were to result in a loss of or damage to our data or applications, or inappropriate disclosure of personal, confidential or proprietary information, we could incur liability and the further development of any of vidutolimod and future product candidates could be delayed.

We may be unable to adequately protect our information systems from cyberattacks, which could result in the disclosure of confidential or proprietary information, including personal data, damage our reputation, and subject us to significant financial and legal exposure.

We rely on information technology systems that we or our third-party providers operate to process, transmit and store electronic information in our day-to-day operations. In connection with our product discovery efforts, we may collect and use a variety of personal data, such as names, mailing addresses, email addresses, phone numbers and clinical trial information. A successful cyberattack could result in the theft or destruction of intellectual property, data, or other misappropriation of assets, or otherwise compromise our confidential or proprietary information and disrupt our operations. Cyberattacks are increasing in their frequency, sophistication and intensity, and have become increasingly difficult to detect. Cyberattacks could include wrongful conduct by hostile foreign governments, industrial espionage, wire fraud and other forms of cyber fraud, the deployment of harmful malware, denial-of-service, social engineering fraud or other means to threaten data security, confidentiality, integrity and availability. A successful cyberattack could cause serious negative consequences for us, including, without limitation, the disruption of operations, the misappropriation of confidential business information, including financial information, trade secrets, financial loss and the disclosure of corporate strategic plans. Although we devote resources to protect our information systems, we realize that cyberattacks are a threat,

102

and there can be no assurance that our efforts will prevent information security breaches that would result in business, legal, financial or reputational harm to us, or would have a material adverse effect on our results of operations and financial condition. Any failure to prevent or mitigate security breaches or improper access to, use of, or disclosure of our clinical data or patients’ personal data could result in significant liability under state (e.g., state breach notification laws), federal (e.g., HIPAA, as amended by the HITECH Act), and international law (e.g., the GDPR) and may cause a material adverse impact to our reputation, affect our ability to conduct new studies and potentially disrupt our business.

We rely on our third-party providers to implement effective security measures and identify and correct for any such failures, deficiencies or breaches. If we or our third-party providers fail to maintain or protect our information technology systems and data integrity effectively or fail to anticipate, plan for or manage significant disruptions to our information technology systems, we or our third-party providers could have difficulty preventing, detecting and controlling such cyber-attacks and any such attacks could result in the losses described above as well as disputes with physicians, patients and our third-party contractors, regulatory sanctions or penalties, increases in operating expenses, expenses or lost revenues or other adverse consequences, any of which could have a material adverse effect on our business, results of operations, financial condition, prospects and cash flows. Any failure by such third parties to prevent or mitigate security breaches or improper access to or disclosure of such information could have similarly adverse consequences for us. If we are unable to prevent or mitigate the impact of such security or data privacy breaches, we could be exposed to litigation and governmental investigations, which could lead to a potential disruption to our business. By way of example, In California, the California Consumer Privacy Act (CCPA) was enacted in June 2018, became effective on January 1, 2020, and became subject to enforcement by the California Attorney General’s office on July 1, 2020. The CCPA broadly defines personal information, and creates new individual privacy rights and protections for California consumers (as defined in the law), places increased privacy and security obligations on entities handling personal data of consumers or households, and provides for civil penalties for violations and a private right of action for data breaches. The CCPA requires covered companies to provide certain disclosures to consumers about its data collection, use and sharing practices, and to provide affected California residents with ways to opt-out of certain sales or transfers of personal information. While there is an exception for protected health information that is subject to HIPAA and clinical trial regulations, the CCPA may impact our business activities if we become a “Business” regulated by the scope of the CCPA. In addition to the CCPA, new privacy and data security laws have been proposed in more than half of the states in the U.S. and in the U.S. Congress, reflecting a trend toward more stringent privacy legislation in the U.S. The effects of the CCPA, and other similar state or federal laws, are potentially significant and may require us to modify our data processing practices and policies and to incur substantial costs and potential liability in an effort to comply with such legislation.

With respect to foreign laws and regulations with respect to data privacy and security, the GDPR went into effect in the European Union in May 2018 and introduces strict requirements for processing the personal data of EU data subjects. Companies that must comply with the GDPR face increased compliance obligations and risk, including more robust regulatory enforcement of data protection requirements and potential fines for noncompliance of up to €20 million or 4% of the annual global revenues of the noncompliant company, whichever is greater.

Many jurisdictions outside of Europe where we do business directly or through master resellers today and may seek to expand our business in the future, are also considering and/or have enacted comprehensive data protection legislation. These include Australia, Brazil, China, Japan, Mexico and Singapore. We also continue to see jurisdictions imposing data localization laws.For example, Russian laws require personal information of Russian citizens to be, among other data processing operations, initially collected, stored, and modified in Russia. These and similar regulations may interfere with our intended business activities, inhibit our ability to expand into those markets, require modifications to our products or services or prohibit us from continuing to offer services in those markets without significant additional costs.

Many jurisdictions outside of Europe where we may do clinical trials or otherwise conduct business in future, are also considering and/or have enacted comprehensive data protection legislation. We also continue to see

103

jurisdictions imposing data localization laws. These and similar regulations may interfere with our intended business activities, inhibit our ability to expand into those markets, require modifications to our products or services or prohibit us from continuing to offer services in those markets without significant additional costs.

Because the interpretation and application of many privacy and data protection laws (including the GDPR), commercial frameworks, and standards are uncertain, it is possible that these laws, frameworks, and standards may be interpreted and applied in a manner that is inconsistent with our existing data management practices and policies. If so, in addition to the possibility of fines, lawsuits, breach of contract claims, and other claims and penalties, we could be required to fundamentally change our business activities and practices or modify our solutions, which could have an adverse effect on our business. Any inability to adequately address privacy and security concerns, even if unfounded, or comply with applicable privacy and security or data security laws, regulations, and policies, could result in additional cost and liability to us, damage our reputation, inhibit our ability to conduct trials, and adversely affect our business.

Our employees, principal investigators, CROs and consultants may engage in misconduct or other improper activities, including non-compliance with regulatory standards and requirements and insider trading.

We are exposed to the risk that our employees, principal investigators, CROs and consultants may engage in fraudulent conduct or other illegal activity. Misconduct by these parties could include intentional, reckless or negligent conduct or disclosure of unauthorized activities to us that violate the regulations of the FDA and other regulatory authorities, including those laws requiring the reporting of true, complete and accurate information to such authorities; healthcare fraud and abuse laws and regulations in the United States and abroad; or laws that require the reporting of financial information or data accurately. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Activities subject to these laws also involve the improper use of information obtained in the course of clinical trials or creating fraudulent data in our pre-clinical studies or clinical trials, which could result in regulatory sanctions and cause serious harm to our reputation. We adopted a code of conduct applicable to all of our employees, but it is not always possible to identify and deter misconduct by employees and other third parties, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations. Additionally, we are subject to the risk that a person could allege such fraud or other misconduct, even if none occurred. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business, including the imposition of civil, criminal and administrative penalties, damages, monetary fines, possible exclusion from participation in Medicare, Medicaid and other federal healthcare programs, contractual damages, reputational harm, diminished profits and future earnings, and curtailment of our operations, any of which could adversely affect our ability to operate our business and our results of operations.

Our third-party manufacturers and suppliers use biological materials and may use hazardous materials, and any claims relating to improper handling, storage or disposal of these materials could be time consuming or costly and could have a material adverse effect on the success of our business.

Our third-party manufacturers and suppliers may use hazardous materials, including chemicals and biological agents and compounds that could be dangerous to human health and safety or the environment. The operations of our third-party manufacturers and suppliers also produce hazardous waste products. We and our third-party manufacturers are subject to numerous environmental, health and safety laws and regulations, including those governing laboratory procedures and the handling, use, storage, treatment and disposal of hazardous materials and wastes. We cannot entirely eliminate the risk of contamination or injury from these materials or wastes. In the event of contamination or injury resulting from our use of hazardous materials, we could be held liable for any resulting damages, and any liability could exceed our resources.

104

Although we maintain workers’ compensation insurance to cover us for costs and expenses, we may incur due to injuries to our employees resulting from the use of hazardous materials, this insurance may not provide adequate coverage against potential liabilities. We do not maintain insurance for environmental liability or toxic tort claims that may be asserted against us in connection with our storage or disposal of biological, hazardous or radioactive materials. Accordingly, in the event of contamination or injury, we could be held liable for damages or be penalized with civil or criminal fines in an amount exceeding our resources, and our clinical trials or regulatory approvals could be suspended.

In addition, we may incur substantial costs in order to comply with current or future environmental, health and safety laws and regulations. These current or future laws and regulations may impair our research, development or commercialization efforts. Failure to comply with these laws and regulations also may result in substantial fines, penalties or other sanctions.

Item 1B. Unresolved Staff Comments.

None.

Item 2. Properties.

We lease a facility containing of approximately 1,163 square feet of office space for our principal office, which is located at 245 Main Street, 2nd Floor, Cambridge, MA 02142. We license these private offices which are located within a shared workspace on a flexible lease with the Cambridge Innovation Center (“CIC”), which is consistent with CIC’s terms for all tenants.

We believe that our facilities are adequate to meet our current needs and that suitable additional or substitute space at commercially reasonable terms will be available as needed to accommodate any future expansion of our operations.

Item 3. Legal Proceedings.

From time to time, we may be involved in lawsuits, claims, investigations and proceedings, consisting of intellectual property, commercial, employment and other matters which arise in the ordinary course of business. While the outcome of any such proceedings cannot be predicted with certainty, as of December 31, 2021, we were not party to any legal proceedings that we would expect to have a material adverse impact on our financial position, results of operations or cash flows.

Item 4. Mine Safety Disclosures.

Not applicable.

105

PART II

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

On August 7, 2020, our common stock began trading on the Nasdaq Global Select Market under the symbol “CMPI”. Prior to that time, there was no public market for our common stock.

Stockholders

As of March 25, 2022, there were 23 stockholders of record of our common stock. The actual number of holders of our common stock is greater than this number of record holders, and includes stockholders who are beneficial owners, but whose shares are held in street name by brokers or held by other nominees. This number of holders of record also does not include stockholders whose shares may be held in trust by other entities.

Dividend Policy

We have never paid or declared any cash dividends on our common stock, and we do not anticipate paying any cash dividends on our common stock in the foreseeable future. We intend to retain all available funds and any future earnings to fund the development and expansion of our business. Any future determination to pay dividends will be at the discretion of our board of directors and will depend upon a number of factors, including our results of operations, financial condition, future prospects, contractual restrictions, restrictions imposed by applicable law and other factors that our board of directors deems relevant.

Equity Compensation Plans

The information required by Item 5 of Form 10-K regarding equity compensation plans is incorporated herein by reference to Item 12 of Part III of this Annual Report.

Issuer Purchases of Equity Securities

We did not purchase any of our registered equity securities during the period covered by this Annual Report.

Recent Sales of Unregistered Securities and Use of Proceeds

Set forth below is information regarding stock options granted and exercised by us during the period covered by this Annual Report on Form 10-K that were not registered under the Securities Act. Included is the consideration, if any, we received for such shares and options and information relating to the section of the Securities Act or the Securities and Exchange Commission, under which exemption from registration was claimed.

Grants and Exercises of Stock Options under Equity Plans

During the period covered by this Form 10-K, we granted options to purchase an aggregate of 1,484,433 shares of common stock, with exercise prices ranging from $3.12 to $15.65 per share, to directors, employees and consultants pursuant to our 2020 Stock Option and Grant Plan, as amended (the “2020 Plan”). In 2021, 70,174 shares of common stock were issued for gross proceeds of $0.1 million upon the exercise of stock options pursuant to the 2020 Plan.

No underwriters were involved in the foregoing issuance of securities. The issuances of the securities described above were deemed to be exempt from registration pursuant to Section 4(a)(2) of the Securities Act or Rule 701 promulgated under the Securities Act as transactions pursuant to compensatory benefit plans. The

106

shares of common stock issued upon the exercise of options are deemed to be restricted securities. All recipients either received adequate information about us or had access, through employment or other relationships, to such information.

Use of Proceeds from our Public Offering of Common Stock

On August 11, 2020, we closed our IPO, in which we issued and sold 5,000,000 shares of common stock, at a public offering price of $15.00 per share. All of the shares of common stock issued and sold in our IPO were registered under the Securities Act pursuant to a registration statement on Form S-1 (File No. 333-239932), which was declared effective by the SEC on August 6, 2020. BofA Securities, Jefferies and BMO Capital Markets acted as joint book-running managers for the offering.

The aggregate net proceeds to us from the public offering, inclusive of the partial over-allotment exercise, was approximately $67.7 million, after deducting underwriting discounts and commissions and other offering expenses payable by us of approximately $8.9 million. No offering expenses were paid directly or indirectly to any of our directors or officers (or their associates) or persons owning 10% or more of any class of our equity securities or to any other affiliates.

There has been no material change in the planned use of IPO proceeds from that described in the Prospectus filed with the SEC pursuant to Rule 424(b)(4) under the Securities Act of 1933, as amended, on August 7, 2020.

Item 6. [Reserved.]

Not applicable.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following discussion should be read in conjunction with our consolidated financial statements and accompanying footnotes appearing elsewhere in this Annual Report on Form 10-K. Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report on Form 10-K, including information with respect to our plans and strategy for our business and related financing, includes forward-looking statements that involve risks and uncertainties. See “Special Note Regarding Forward-Looking Statements.” Because of many factors, including those factors set forth in Part I, Item 1A “Risk Factors” in this Annual Report on Form 10-K, our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis. We do not assume any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

Overview

We are a clinical-stage biotechnology company focused on developing and commercializing our proprietary technology to harness the power of the immune system to combat cancer. Our product candidate, vidutolimod (formerly CMP-001), is a differentiated Toll-like receptor 9 (“TLR9”), agonist delivered as a noninfectious biologic virus-like particle (“VLP”), utilizing a CpG-A oligonucleotide as a key component. When injected into a tumor, vidutolimod is designed to trigger the body’s innate immune system, thereby altering the tumor microenvironment and directing activated anti-tumor T cells to attack both the injected tumor and also tumors throughout the body. In a clinical trial of vidutolimod in combination with a systemic checkpoint inhibitor (“CPI”), in patients whose tumors were unresponsive or no longer responsive to a CPI, we have observed a best objective response rate (“ORR”), of 28% (27/98), including post-progression responders. We are evaluating vidutolimod across multiple tumor types in combination with other immunotherapy agents. Our founder, Art Krieg, first reported the discovery of immunostimulatory cytosine-phosphate-guanine (“CpG”), DNA in 1995, which, combined with the discovery of TLR9, led to the recognition that synthetic CpG-A oligonucleotides have

107

the potential to stimulate the TLR9 receptor for therapeutic purposes. Our goal is to establish vidutolimod as a foundational immuno-oncology therapy that engages the innate immune system to fight cancer and improve outcomes for patients with a broad range of solid tumors.

Since our inception, we have devoted substantially all of our efforts and financial resources to the research and development activities related to our technology and our vidutolimod program, and the administrative support for such activities including raising capital, business planning, undertaking pre-clinical studies and clinical trials and other support activities. We do not have any products approved for sale and have not generated any revenue from product sales or any other sources and do not expect to generate any revenue for the next several years. We have not yet successfully completed any registrational clinical trials, obtained any regulatory approvals, manufactured a commercial-scale drug, or conducted sales and marketing activities.

We have funded our operations to date primarily with proceeds from the sale of preferred stock, convertible debt and common stock. Since inception, we have received net cash proceeds of $241.7 million from sales of our preferred stock, convertible debt and common stock.

We have incurred recurring losses and had negative operating cash flows since inception and our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of vidutolimod or any other products we acquire or develop. Our net losses were $36.9 million and $61.4 million for the years ended December 31, 2020 and 2021, respectively. We expect to continue to incur significant expenses and to increase operating losses for at least the next several years.

We expect our expenses and capital requirements will increase substantially in connection with our ongoing activities, particularly as we:

• conduct our current and any additional clinical trials of vidutolimod, including, among others, our current Phase 2 trial in anti-PD-1 refractory melanoma, our current randomized Phase 2/3 trial in first-line melanoma, our current Phase 2 proof of concept trial in head and neck squamous cell carcinoma, and our current Phase 2 proof of concept trial with patient cohorts in anti-PD-1 naïve and anti-PD-1 refractory CSCC and MCC;

• conduct the necessary scale-up activities to support the potential commercialization of vidutolimod, if approved;

• conduct research and preclinical development of any future product candiates

• hire additional clinical and scientific personnel to support our ongoing preclinical activities and clinical trials of vidutolimod and any other product candidates we choose to develop;

• seek marketing approval for vidutolimod and any other product candidates that successfully complete clinical development;

• acquire or in-license additional product candidates;

• maintain compliance with applicable regulatory requirements;

• maintain, expand, protect and enforce our intellectual property portfolio;

• develop and expand our sales, marketing and distribution capabilities for vidutolimod and any other product candidates for which we obtain marketing approval;

• expand our operational, financial and management systems and increase administrative personnel, including to support our clinical development and commercialization efforts and our operations as a public company;

• encounter continued delays or interruptions related to current development activities, our supply chain, or the third-parties on whom we rely due to the ongoing COVID-19 pandemic and otherwise; and

• expand our infrastructure and facilities to accommodate the planned growth of our employee base;

108

As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and marketing and distribution or licensing arrangements. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on favorable terms, or at all. If we fail to raise capital or enter into such agreements as, and when, needed, we may have to significantly delay, scale back or discontinue the development and commercialization of vidutolimod or any of our future product candidates.

Since our inception in 2015, through venture funding and our IPO in August 2020, we have raised $241.7 million. Our private rounds included prominent biotechnology institutional investors including Sofinnova Investments, venBio Partners, F-Prime Capital, Decheng Capital, Longitude Capital, Novo Holdings, Medixci, Omega Funds, Clough Capital Partners, Sectoral Asset Management, and BrightEdge, the venture investment fund of the American Cancer Society.

Risks and Uncertainties

We are subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, the outcome of clinical trials, development by competitors of new therapeutics and technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations, ability to secure additional capital to fund operations, and risks associated with the ongoing COVID-19 global pandemic or future pandemics, including known and potential additional delays associated with our ability to enroll our ongoing trials. There can be no assurance that we will be able to successfully raise sufficient additional capital or complete in a timely manner the development of, or receive regulatory approval for, any products developed, and if approved, that any products will be commercially viable. Any products resulting from our current research and development efforts will require significant additional research and development, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel, infrastructure and extensive compliance reporting capabilities. We have not generated any revenues from the sale of any products to date. Even if our product development efforts are successful, it is uncertain when, if ever, we will realize significant revenue from product sales.

We need to obtain significant additional funding and may seek additional funding through private or public equity financings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing agreements. If we are unable to obtain additional funding, we may be forced to delay, reduce or eliminate some or all of our research and development programs, which could adversely affect our business prospects, or we may be unable to continue operations. There is no assurance that we will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all.

We believe that our existing cash, cash equivalents and available-for-sale investments of $70.9 million as of December 31, 2021 will enable us to fund our operating expenses and capital expenditure requirements through the end of 2022. Because our current operating plan does not contain sufficient resources, we require additional external sources of capital to complete our planned clinical programs for vidutolimod, including completing our ongoing clinical trials. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. Because of the uncertainty in securing additional capital, we have concluded that substantial doubt exists with respect to our ability to continue as a going concern within one year after the date of the filing of this Annual Report on Form 10-K.

Because of the numerous risks and uncertainties associated with pharmaceutical product development, we are unable to accurately predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations. To the extent that

109

we raise additional capital through the sale of equity or convertible debt securities, your ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect your rights as a common stockholder.

Inflation generally affects us by increasing our cost of labor and clinical trial costs. We do not believe that inflation had a material effect on our results of operations during the year ended December 31, 2021

COVID-19

In March 2020 the World Health Organization declared the global novel coronavirus disease 2019 (“COVID-19”) a pandemic. Despite progress with distribution and administration of vaccines, COVID-19 and its effects continue to evolve, particularly in light of emerging variants, such as Delta and Omicron. Although we have experienced some impact of the ongoing COVID-19 pandemic on our business and operations, including delays in initiation of study sites and enrolling patients, we cannot currently predict the scope and severity of any potential business shutdowns or disruptions or the resulting impact on clinical trials as the pandemic evolves. Our clinical trials that commenced during the COVID-19 pandemic have been and continue to be adversely affected by the COVID-19 pandemic, resulting in patient enrollment delays. As a result, in December 2021, we revised our expectations with respect to the anticipated timing of clinical data milestones in our Phase 2 clinical trial in anti-PD-1 refractory melanoma patients, our Phase 2/3 trial in first-line melanoma and our Phase 2 clinical trial in head and neck cancer. We are continuing to monitor the latest developments regarding the COVID-19 pandemic, including the emergence of new and potentially more contagious strains of the virus, and the resulting impact on our ability to enroll our clinical trials. The financial impact of the COVID-19 pandemic cannot be reasonably estimated at this time and this pandemicmay continue to have a material adverse impact on our business, financial condition and results of operations.

Components of Our Results of Operations

Revenue

To date, we have not generated any revenue from any sources and do not expect to generate any revenue from the sale of products for the next several years. If our development efforts for vidutolimod or any future product candidates are successful and result in regulatory approval, we may generate revenue in the future from product sales. However, we cannot predict whether, when, or to what extent we will generate revenue from the commercialization and sale of vidutolimod or any future product candidates as we may never succeed in obtaining regulatory approval for any of our product candidates. If we enter into license or collaboration agreements for any of our product candidates or intellectual property, we may generate revenue in the future from payments as a result of such license or collaboration agreements, however there can be no assurance that we will be able to enter into any license or collaboration agreements.

Operating Expenses

Research and Development Expenses

Research and development expenses consist primarily of costs incurred for our research activities and the development of our VLP technology and our vidutolimod program and include:

• expenses incurred in connection with the preclinical and clinical development of our technology and vidutolimod, including clinical trials under agreements with contract research organizations (“CROs”), clinical investigators and consultants;

• employee-related expenses, including salaries, benefits and travel and stock-based compensation expense, for employees engaged in research and development functions;

• the cost of contract manufacturing organizations (“CMOs”), that manufacture drug product for use in our preclinical studies and clinical trials and perform analytical testing, scale-up and other services in connection with our development activities;

110

• costs related to compliance with regulatory requirements;

• payments made under third-party licensing agreements, such as the exclusive license agreement we entered into in 2015 with Cytos Biotechnology LTD (now Kuros Biosciences AG, or “Kuros”) (the “Kuros License Agreement”);

• facilities and other expenses, which include direct and allocated expenses for facilities, insurance and supplies; and

• costs related to compliance with regulatory requirements.

We recognize external development costs based on an evaluation of the progress to completion of specific tasks using information provided to us by our service providers. This process involves reviewing open contracts, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. Any nonrefundable advance payments that we make for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. Such amounts are expensed as the related goods are delivered or the related services are performed, or until it is no longer expected that the goods will be delivered or the services rendered.

Upfront payments under license agreements are expensed upon receipt of the license, and any annual maintenance fees under license agreements are expensed in the period in which they are incurred. Milestone payments under license agreements are accrued and a corresponding expense is recognized in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable.

We do not track our research and development expenses by indication. Our direct external research and development expenses consist primarily of external costs, such as fees paid to CROs, CMOs, research/testing laboratories and outside consultants in connection with our preclinical development, process development, manufacturing and clinical development activities. Our direct research and development expenses also include fees incurred under licensing agreements. We do not allocate these costs to specific indications because they are deployed across the entire the vidutolimod development program and, as such, are not separately classified. We use internal resources primarily to manage our preclinical development, outsourced clinical trials, process development, manufacturing and clinical development activities. These employees work across the entire the vidutolimod development program and, therefore, we do not track their costs by indication.

Research and development activities are central to our business model. Product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. As a result, we expect that our research and development expenses will continue to increase substantially over the next several years as we advance vidutolimod into later stages of clinical development toward potential regulatory approval, advance vidutolimod for additional indications, as well as conduct translational research efforts and other preclinical and clinical development, including submitting regulatory filings for any other product candidates we may acquire or develop. In addition to the expected increase in third-party costs, we expect our personnel costs, including costs associated with stock-based compensation, will also increase substantially in the future. In addition, as we advance vidutolimod into potentially registrational clinical trials and, subject to positive data and regulatory approvals, potentially commercialize vidutolimod, we expect to incur additional expenses from milestone and royalty payments related to the Kuros License Agreement.

We do not believe that it is possible at this time to accurately project total program-specific expenses through commercialization of vidutolimod or any other product candidates we may acquire or develop. This is due to numerous factors, some of which are beyond our control, that are associated with the successful

111

development and commercialization of vidutolimod and any other product candidates we may acquire or develop, including the following:

• the scope, progress, outcome and costs of our preclinical studies and clinical trials for vidutolimod or any other product candidates we may acquire or develop;

• making arrangements with third-party manufacturers for both clinical and commercial supplies of vidutolimod or any other product candidates;

• successful patient enrollment in, and the initiation and completion of clinical trials in a timely manner;

• raising additional funds necessary to complete clinical development and the potential commercialization, of vidutolimod or any other product candidates;

• receipt, timing and related terms of marketing approvals from applicable regulatory authorities;

• the extent of any required post-marketing approval commitments to applicable regulatory authorities;

• developing and implementing marketing and reimbursement strategies;

• establishing sales, marketing and distribution capabilities and launching commercial sales of vidutolimod or any other products, if approved, whether alone or in collaboration with others;

• acceptance of vidutolimod or any other products, if approved, by patients, the medical community and third-party payors;

• effectively competing with other therapies and/or changes in standard of care;

• obtaining and maintaining third-party coverage and adequate reimbursement;

• obtaining and maintaining patent, trade secret and other intellectual property protection and regulatory exclusivity for our product candidates;

• protecting and enforcing our rights in our intellectual property portfolio;

• significant and changing government regulations; and

• maintaining an acceptable tolerability profile of the products following approval, if any.

A change in the outcome of any of these variables with respect to the development of vidutolimod or any future product candidates would significantly change the costs and timing associated with the development of that product candidate. We may never succeed in obtaining regulatory approval for any product candidate.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and benefits, stock-based compensation and travel expense for personnel in executive, business development, finance, human resources, legal and support functions. General and administrative expenses also include direct and allocated facility-related costs as well as insurance costs and professional fees for legal, patent, consulting, accounting and audit services, investor and public relations services and outsourced information technology services.

We anticipate that our general and administrative expenses will continue to increase in the future as we increase our headcount to support the continued advancement of vidutolimod toward potential commercialization and the future development of any other product candidates that we may pursue. We also anticipate that we will continue to experience an increase in accounting, audit, legal, regulatory, compliance and director and officer insurance costs as well as investor and public relations expenses associated with operating as a public company. Additionally, if we believe a regulatory approval of vidutolimod or any other product candidate appears likely, we anticipate an increase in payroll and other employee-related expenses as a result of our preparation for commercial operations to market and sell that product candidate.

112

Interest Income

Interest income consists of interest earned on our cash, cash equivalent and available-for-sale investments balances. We expect that our interest income will fluctuate based on prevailing interest rates, our ability to raise additional funds, as well as the amount of expenditures for our clinical development of vidutolimod and ongoing business operations

Income Taxes

There were no provisions for income taxes for the years ended December 31, 2020 and 2021 because we have historically incurred operating losses and we maintain a full valuation allowance against our net deferred tax assets.

Results of operations

Comparison of the years ended December 31, 2021 and 2020

The following table summarizes our sources and uses of cash for each of the periods presented:

	Year ended December 31,						Increase (Decrease)
	2021			2020
	(in thousands)
Operating expenses:
Research and development	$	45,819		$	26,719		$	19,100
General and administrative		15,651			10,185			5,466
Total operating expenses		61,470			36,904			24,566
Loss from operations		(61,470	)		(36,904	)		24,566
Interest income		100			79			21
Loss on sale of available-for-sale investments		(35	)		—			35
Change in fair value of convertible notes		—			(83	)		(83	)
Total other income (expense)		65			(4	)		69
Net loss	$	(61,405	)	$	(36,908	)	$	24,497

Research and Development Expenses

Research and development expenses were $45.8 million in 2021 compared to $26.7 million in 2020. The increase of approximately $19.1 million was primarily related to combined royalty payments of $6.0 million to Kuros which became payable upon the Company initiating dosing of patients in trials which triggered Phase 2 and Phase 3 milestone payments; an increase in clinical trial costs of $6.3 million and outsourced contract manufacturing costs of $3.7 million related to greater activity in our ongoing clinical trials; and additional personnel and consulting costs of $1.5 and stock-based compensation costs of $1.4 million both associated with increased staffing.

General and Administrative Expenses

General and administrative expenses were $15.7 million in 2021 compared to $10.2 million in 2020. The $5.5 million increase is primarily due to expanding our infrastructure to support being a publicly traded company for all of 2021 and included increases in directors and officers insurance of $2.1 million, stock-based compensation of $2.0 million, and professional fees for legal, accounting, recruiting and other public company related costs of $1.0 million.

113

Other income (expense), net

Other income, net in 2021 included interest income of $0.1 million, which was partially offset by losses on sale of available-for-sale investments of $35,000.    

Other expense, net in 2020 included $0.1 million of interest income slightly more than offset by the change in fair value of convertible notes.

Liquidity and capital resources

Overview

We have funded our operations to date primarily with proceeds from the sale of preferred stock, convertible debt and common stock. Since inception and through December 31, 2021, we have received net cash proceeds of $241.7 million from sales of our preferred stock, convertible debt and common stock. In April 2020, we received $10.0 million from the issuance of convertible loan notes and in June 2020, we received $74.6 million in additional net proceeds from the sale of Series C preferred stock.

In August 2020, we completed an IPO in which we received net proceeds of approximately $67.7 million. In connection with the IPO, all outstanding shares of our redeemable preferred stock were converted to common stock.

On September 7, 2021, we filed a shelf registration statement on Form S-3 (File No. 333-259353), which was declared effective by the SEC on September 15, 2021 (the “Shelf Registration Statement”). Under the Shelf Registration Statement, we may offer and sell, from time to time, various securities in an aggregate amount of up to $150 million. In connection with filing the Registration Statement, we entered into an Open Market Sale AgreementSM (the “2021 Sales Agreement”), with Jefferies LLC (“Jefferies”), pursuant to which we may offer and sell, from time to time, shares of our common stock having an aggregate offering of up to $50.0 million through Jefferies as our sales agent. As of December 31, 2021, no shares of common stock have been sold and no net proceeds have been received by us pursuant to the 2021 Sales Agreement.

As of the date of this Annual Report on Form 10-K, we have not generated any product sales. We do not know when, or if, we will generate revenue from product sales. We will not generate significant revenue from product sales unless and until we obtain regulatory approval and commercialize one of our current or future product candidates. Our primary uses of capital are, and we expect will continue to be, compensation and related expenses, third-party clinical and contract manufacturing costs, legal and other regulatory expenses, and general overhead costs. We expect that we will continue to generate losses for the foreseeable future, and we expect the losses to increase as we continue the development of, and seek regulatory approvals for, our product candidates, and begin to commercialize any approved products. We are subject to risks in the development of our products, and we may encounter unforeseen expenses, difficulties,complications, delays and other unknown factors that may adversely affect our business. We expect that we will need substantial additional funding to support our continuing operations.

As of December 31, 2021, we had an accumulated deficit of $201.5 million. We anticipate operating losses to continue for the foreseeable future due to, among other things, costs related conducting clinical trials and our administrative organization. We will require substantial additional financing to fund our operations and to continue to execute our strategy, and we will pursue a range of options to secure additional capital.

If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may be required to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or to grant licenses on terms that may not be favorable to us. If we are unable to raise capital when needed or on acceptable terms, we could be forced to delay, reduce or eliminate our research and development programs or future commercialization efforts.

114

We believe that our existing cash, cash equivalents, and investments of $70.9 million as of December 31, 2021 will enable us to fund our operating expenses and capital expenditure requirements through the end of 2022. Because our current operating plan does not contain sufficient resources, we will require additional external sources of capital to complete the planned clinical programs for vidutolimod, including completing our ongoing clinical trials. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. Because of the uncertainty in securing additional capital, we have concluded that substantial doubt exists with respect to our ability to continue as a going concern within one year after the date of the filing of this Annual Report on Form 10-K.

Cash Flows

The following table summarizes our sources and uses of cash for each of the periods presented:

	Year ended December 31,						Increase (Decrease)
	2021			2020
	( in thousands)
Net cash used in operating activities	$	(53,715	)	$	(38,111	)	$	15,604
Net cash provided by (used in) investing activities		61,189			(83,290	)		144,479
Net cash provided by financing activities		146			160,271			(160,124	)
Net increase in cash, cash equivalents and restricted cash	$	7,620		$	38,870		$	(31,250	)

Operating Activities

During 2021, net cash used in operating activities was $53.7 million, primarily resulting from our net loss of $61.4 million, partially offset by non-cash charges of $6.3 million and cash provided by changes in our operating assets and liabilities of $1.4 million

During 2020, net cash used in operating activities was $38.1 million, primarily resulting from our net loss of $36.9 million and cash used by changes in our operating assets and liabilities of $3.5 million, partially offset by non-cash charges of $2.3 million.

Investing Activities

Net cash provided by investing activities of $61.2 million in 2021 reflects purchase and sales of the Company’s available-for-sale investments of $62.0 million to fund current and future operating activities, partially offset by purchases of machinery and equipment of $0.8 million.

Net cash used in investing activities of $83.3 million in 2020 reflects the investment of the proceeds from our Series B and Series C preferred stock financings and the IPO into investments.

Financing Activities

Net cash provided by financing activities in 2021 was $0.1 million and consisted of proceeds from the exercise of stock options.

Net cash provided by financing activities in 2020 was $160.3 million and consisted of the net proceeds from our IPO of $67.7 million, the issuance of Series B preferred stock and Series C preferred stock of $82.5 million and the proceeds from the issuance of convertible notes of $10.0 million.

Funding Requirements

We expect our expenses to increase substantially in connection with our ongoing activities, particularly as we advance the preclinical activities and clinical trials for vidutolimod and any other product candidates that we

115

may develop or acquire in the future. In addition, we have incurred, and expect to incur, additional costs associated with operating as a public company, including significant legal, accounting, investor relations and other expenses that we did not incur as a private company. The timing and amount of our operating expenditures will depend largely on:

• the extent to which we experience delays or interruptions to preclinical studies and clinical trials, to our third-party service providers on whom we rely, or to our supply chain due to the ongoing COVID-19 pandemic or otherwise;

• the initiation, progress, timing, costs and results of current and future preclinical studies and clinical trials for vidutolimod and any other product candidates we may develop or acquire in the future;

• the cost and timing of the manufacture of additional clinical trial materials and the completion of commercial-scale outsourced manufacturing activities;

• the costs and timing to seek and obtain regulatory approvals for any product candidates that successfully complete clinical trials;

• the need to hire additional clinical, quality assurance, quality control and other scientificpersonnel;

• the number and characteristics of product candidates that we develop or may in-license;

• the outcome, timing and cost of meeting and maintaining compliance with regulatory requirements established by the U.S. Food and Drug Administration (the “FDA”), the European Medical Agency (the “EMA”) and other comparable foreign regulatory authorities;

• the cost of filing, prosecuting, defending and enforcing our patent claims and other intellectual property rights;

• the terms of any collaboration agreements we may choose to enter into;

• the cost associated with the expansion of our operational, financial and management systems and increased personnel, including personnel to support our operations as a public company; and

• the cost of establishing sales, marketing and distribution capabilities for any product candidates for which we may receive regulatory approval in regions where we choose to commercialize our products, if approved, on our own.

Until such time, if ever, as we can generate substantial product revenue, we expect to finance our operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. We do not currently have any committed external source of funds. To the extent that we raise additional capital through the sale of equity or convertible debt securities, ownership interests may be materially diluted, and the terms of such securities could include liquidation or other preferences that adversely affect your rights as a common stockholder. Debt financing and preferred equity financing, if available, may involve agreements that include restrictive covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. In addition, debt financing would result in fixed payment obligations. If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings or other arrangements when needed, we may be required to delay, limit, reduce or terminate our research, product development or future commercialization efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Contractual obligations and other commitments

We enter into contracts in the normal course of business with CROs, CMOs and other third parties for clinical trials, preclinical research studies and testing and manufacturing services. These contracts are cancelable

116

by us upon prior written notice. Payments due upon cancellation consist only of payments for services provided or expenses incurred, including noncancelable obligations of our service providers, up to the date of cancellation. The amount and timing of such payments are not known.

We have also entered into license and collaboration agreements with third parties, which are in the normal course of business. We have not included future payments under these agreements since obligations under these agreements are contingent upon future events such as our achievement of specified development, regulatory, and commercial milestones, or royalties on net product sales.

Pursuant to the Kuros License Agreement, we are required to make payments to Kuros for each product that achieves certain development and regulatory milestones. We may be obligated to make up to $56.0 million in milestone payments to Kuros related to vidutolimod. We are also required to pay royalties on sales of future products, if any. Through December 31, 2021, the Company has incurred license fees and milestone payments totaling $8.3 million, including $6.0 million in 2021. Cost incurred in 2021 relate to: (i) a $2.0 million milestone payment in connection with the dosing of the first patient in the Phase 2/3 first-line melanoma trial for vidutolimod and (ii) a $4.0 million milestone payment in connection with the dosing of a first patient in a Phase 2 trial of vidutolimod in combination with nivolumab for the treatment of patients with anti-PD-1 refractory melanoma and to potentially support a Biologics License Application (“BLA”) and marketing approval of vidutolimod. Future milestone payments will be due upon filing for regulatory approval in each of the United States, Europe and the Far East and for ultimate approval in each of those regions.

We do not currently have any long-term leases. We rent our office space in Cambridge, Massachusetts based on a month-to-month license agreement with the landlord.

Critical accounting policies and significant judgments and estimates

Our consolidated financial statements are prepared in accordance with GAAP. The preparation of our consolidated financial statements and related disclosures requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, costs and expenses. We base our estimates on historical experience, known trends and events and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ from these estimates under different assumptions or conditions.

While our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements, we believe that the following accounting policies are the most critical to the judgement and estimates used in the preparation of our consolidated financial statements.

Accrued Research and Development Expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued research and development expenses. This process involves reviewing open contracts, communicating with our applicable personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. The majority of our service providers invoice us in arrears for services performed, on a pre-determined schedule or when contractual milestones are met; however, some require advance payments. We make estimates of our accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of the estimates with the service providers and make adjustments if necessary. Examples of estimated accrued research and development expenses include fees paid to:

• CROs in connection with preclinical and clinical trials;

117

• CMOs and other providers in connection with the production of preclinical and clinical trial materials;

• investigative sites in connection with clinical trials; and

• other vendors in connection with our preclinical development activities.

We base our expenses related to preclinical studies and clinical trials on our estimates of the services received and efforts expended pursuant to quotes and contracts with multiple research institutions and CROs that conduct and manage preclinical studies and clinical trials on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, we adjust the accrual or prepaid expense accordingly. Although we do not expect our estimates to be materially different from amounts actually incurred, the estimated status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period.

Stock-Based Compensation

We measure all stock-based awards granted based on their estimated fair value on the date of the grant and recognize the corresponding compensation expense for those awarded to employees and directors over the requisite service period, which is generally the vesting period of the respective award, and for those awarded to nonemployees over the period during which services are rendered by nonemployees until completed. We have typically issued stock options and restricted stock awards with service-based vesting conditions and we record the expense for these awards using the straight-line method.

We estimate the fair value of each stock option grant using the Black-Scholes option-pricing model, which uses assumptions we make for the volatility of our common stock, the expected term of our stock options, the risk-free interest rate for a period that approximates the expected term of our stock options and our expected dividend yield.

The fair value of our common stock is also an input used to determine the fair value of stock options. Prior to the IPO, the estimated fair value of our common stock had been determined by our board of directors as of the date of each award, with input from management, considering our most recently available third-party valuations of common stock and our board of directors’ assessment of additional objective and subjective factors that it believed were relevant and which may have changed from the date of the most recent valuation through the date of the grant, which intended all options granted to be exercisable at price per share not less than the per share fair value of our common stock underlying those options on the grant date. Subsequent to the IPO, the fair value of our common stock is the closing selling price per share of our common stock as reported on the Nasdaq Global Market on the date of grant or other relevant determination date.

Recent accounting pronouncements

A description of recently issued and recently adopted accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our consolidated financial statements included elsewhere in this Annual Report on Form 10-K.

Emerging Growth Company and Smaller Reporting Company Status

The Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), permits an “emerging growth company” such as us to take advantage of an extended transition period to comply with new or revised accounting standards applicable to public companies until those standards would otherwise apply to private

118

companies. We have elected to not “opt out” of this provision and, as a result, we will adopt new or revised accounting standards at the time private companies adopt the new or revised accounting standard and will do so until such time that we either (i) irrevocably elect to “opt out” of such extended transition period or (ii) no longer qualify as an emerging growth company. Other exemptions and reduced reporting requirements under the JOBS Act for emerging growth companies include presentation of only two years of audited consolidated financial statements in a registration statement for an initial public offering, an exemption from the requirement to provide an auditor’s report on internal controls over financial reporting pursuant to the Sarbanes-Oxley Act of 2012, an exemption from any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation, and less extensive disclosure about our executive compensation arrangements. We would cease to be an emerging growth company upon the earliest of: (1) the last day of the fiscal year ending after the fifth anniversary of our initial public offering; (2) the last day of the fiscal year in which we have more than $1.07 billion in annual revenue; (3) the last day of the fiscal year in which we qualify as a “large accelerated filer,” with at least $700.0 million of equity securities held by non-affiliates as of the prior June 30th; or (4) the issuance, in any three-year period, by our company of more than $1.0 billion in non-convertible debt securities held by non-affiliates.

We are also a “smaller reporting company” and we may take advantage of certain of the scaled disclosures available to smaller reporting companies until the fiscal year following the determination that (i) the market value of our stock held by non-affiliates is more than $250 million or (ii) our annual revenue was more than $100 million during the most recently completed fiscal year and the market value of our stock held by non-affiliates is more than $700 million measured on the last business day of our second fiscal quarter. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company we may choose to present only the two most recent fiscal years of audited consolidated financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

Interest rate risk

We are exposed to market risk related to changes in interest rates. Our current investment policy is to maintain an investment portfolio consisting mainly of United States money market, government-secured, and high-grade corporate securities, directly or through managed funds, with maturities of twenty-four months or less. Our cash is deposited in and invested through highly rated financial institutions in North America. Our investments are subject to interest rate risk and will fall in value if market interest rates increase. However, due to the conservative nature of our investments, low prevailing market rates and relatively short effective maturities of debt instruments, interest rate risk is mitigated. If market interest rates were to increase immediately and uniformly by 10% from levels at December 31, 2021, we estimate that the fair value of our investment portfolio would decline by an immaterial amount. We do not own derivative financial instruments in our investment portfolio.Our cash and cash equivalents were held in savings accounts at banking institutions and a money market fund that invests in U.S. Government securities. Our primary exposure to market risk is interest income sensitivity, which is affected by changes in the general level of U.S. interest rates. However, because of the short-term nature of the instruments in our portfolio, an immediate 10% change in the interest rate would not have a material impact on the fair market value of our investment portfolio or on our financial position or results of operations.

As of December 31, 2021, we had no debt outstanding and therefore were not subject to interest rate risk related to debt.

Foreign currency exchange risk

Our primary exposure to market risk is foreign exchange rate sensitivity to the British Pound. We recognized foreign currency losses of approximately $18,000 in the 2021. These foreign currency transaction

119

losses were recorded as a component of general and administrative expense in our consolidated statements of operations. At December 31, 2021, an immediate 5% change in the British Pound exchange rate would not have a material effect on our results of operations.

As we continue to grow our business, our results of operations and cash flows may increasingly be subject to fluctuations due to changes in foreign currency exchange rates, which could adversely impact our results of operations. To date, we have not entered into any foreign currency hedging contracts to mitigate our exposure to foreign currency exchange risk.

Item 8. Financial Statements and Supplementary Data

The financial statement and supplemental data required by this item are included after the signature page of the Annual Report on Form 10-K beginning on page F-1.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

None.

Item 9A. Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

We maintain “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), that are designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is (1) recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms and (2) accumulated and communicated to our management, including our principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure. Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of the design and operation of our disclosure controls and procedures as of December 31, 2021. Based upon that evaluation, our Chief Executive Officer and Chief Financial Officer concluded that as of such date, our disclosure controls and procedures were effective at the reasonable assurance level of December 31, 2021.

Management’s Annual Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act as a process designed by, or under the supervision of, a company’s principal executive officer and principal financial officer, or persons performing similar functions, and effected by a company’s board of directors, management, and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles and includes those policies and procedures that:

• pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of a company’s assets;

• provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that a company’s receipts and expenditures are being made only in accordance with authorizations of the company’s management and directors; and

120

• provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Our management assessed the effectiveness of our internal control over financial reporting as of December 31, 2021. In making this assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in Internal Control-Integrated Framework (2013). Based on this evaluation, management has concluded our internal control over financial reporting at December 31, 2021 was effective.

Changes in Internal Control over Financial Reporting

There has been no change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during the fiscal quarter ended December 31, 2021 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Item 9B. Other Information.

None.

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Not applicable.

PART III

Item 10. Directors, Executive Officers and Corporate Governance

Except as set forth below, the information required by this item is incorporated by reference from our definitive Proxy Statement to be filed with the SEC in connection with our 2022 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2021.

We have adopted a Code of Business Conduct and Ethics that applies to all of our directors, officers and employees, including our principal executive officer and principal financial officer. The Code of Business Conduct and Ethics is posted on our website at http://checkmatepharma.com.

We intend to satisfy the disclosure requirement under Item 5.05 of Form 8-K regarding an amendment to, or waiver from, a provision of this Code of Business Conduct and Ethics by posting such information on our website, at the address and location specified above and, to the extent required by the listing standards of The NASDAQ Global Select Stock Market, by filing a Current Report on Form 8-K with the SEC, disclosing such information.

Item 11. Executive Compensation.

The information called for by this item is incorporated by reference from our definitive Proxy Statement to be filed with the SEC in connection with our 2022 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2021.

121

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

The information called for by this item is incorporated by reference from our definitive Proxy Statement to be filed with the SEC in connection with our 2022 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2021.

Item 13. Certain Relationships and Related Transactions, and Director Independence.

The information called for by this item is incorporated by reference from our definitive Proxy Statement to be filed with the SEC in connection with our 2022 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2021.

Item 14. Principal Accounting Fees and Services

Our independent public accounting firm is KPMG LLP, Boston, Massachusetts, United States, PCAOB Auditor ID 185.

The information called for by this item is incorporated by reference from our definitive Proxy Statement to be filed with the SEC in connection with our 2022 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2021.

Part IV

Item 15. Exhibits, Financial Statement Schedules

(a) The following documents are filed as part of this Annual Report on Form 10-K:

1) The following Report and Consolidated Financial Statements of the Company are included in this Annual Report:

Report of Independent Registered Public Accounting Firm	F-2
Consolidated Balance Sheets	F-3
Consolidated Statements of Operations and Comprehensive Loss	F-4
Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity (Deficit)	F-5
Consolidated Statements of Cash Flows	F-6
Notes to Consolidated Financial Statements	F-7

2) No schedules are submitted because they are not applicable, not required or because information is included in the consolidated financial statements or the notes thereto.

3) The exhibits required by Item 601 of Regulation S-K and Item 15(b) of this Annual Report on Form 10-K are listed in the Exhibit Index immediately preceding the signature page of this Annual Report on Form 10-K. The exhibits listed in the Exhibit Index are incorporated by reference herein.

Item 16. Form 10-K Summary

None.

122

Item 15. Exhibits.

EXHIBIT INDEX1

Exhibit Number	Exhibit Description
3.1	Fourth Amended and Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 of the Registrant’s Current Report on Form 8-K (File No. 001-39425) filed on August 14, 2020)
3.2	Second Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.2 of the Registrant’s Current Report on Form 8-K (File No. 001-39425) filed on August 14, 2020)
4.1	Specimen Common Stock Certificate (incorporated by reference to Exhibit 4.1 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
4.3	Description of Securities (incorporated by reference to Exhibit 4.3 of the Registrant’s Annual Report on Form 10K (File No. 333-239932) filed on March 29, 2021)
10.1#	2015 Stock Option and Grant Plan, as amended, and form of award agreements thereunder (incorporated by reference to Exhibit 10.1 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
10.2#	2020 Stock Option and Grant Plan, and form of award agreements thereunder (incorporated by reference to Exhibit 10.2 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
10.3#	2020 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.3 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
10.4#	Separation Agreement and Release between Checkmate Pharmaceuticals, Inc. and Barry Labinger, dated as of October 27, 2021 (incorporated by reference to Exhibit 10.1 of the Registrant’s Current Report on Form 8-K (File No. 333-239932) filed on October 27, 2021)
10.5#	Form of Indemnification Agreement between the Registrant and each of its executive officers (incorporated by reference to Exhibit 10.4 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
10.6#	Form of Indemnification Agreement between the Registrant and each of its (incorporated by reference to Exhibit 10.5 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
10.7#	Interim CEO Agreement between Checkmate Pharmaceuticals, Inc. and Alan Fuhrman, dated as of October 27, 2021 (incorporated by reference to Exhibit 10.2 of the Registrant’s Current Report on Form 8-K (File No. 333-239932) filed on October 27, 2021)
10.8#†	Supply and Non-Exclusive License Agreement, effective as of May 6, 2021, by and between Checkmate Pharmaceuticals, Inc. and Regeneron Pharmaceuticals, Inc. (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q (File No. 333-239932) filed on August 12, 2021)
10.9#	Employment Agreement between the Registrant and Art Krieg, dated April 8, 2020, as amended on August 2, 2020 (incorporated by reference to Exhibit 10.17 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)
10.10#	Executive Employment Agreement by and between the Registrant and James Wooldridge, dated September 19, 2019, as amended on August 2, 2020 (incorporated by reference to Exhibit 10.18 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-239932) filed on August 3, 2020)

123

Exhibit Number	Exhibit Description
10.11#	Executive Employment Agreement by and between the Registrant and Robert Dolski, dated January 4, 2021 (incorporated by reference to Exhibit 10.1 of the Registrant’s Current Report on Form 8-K (File No. 333-39425) filed on January 5, 2021)
10.12†	Supply and Non-Exclusive License Agreement, effective as of May 6, 2021, by and between Checkmate Pharmaceuticals, Inc. and Regeneron Pharmaceuticals, Inc. (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q (File No. 001-39425) filed on August 12, 2021)
10.13†	Master Clinical Trial Collaboration Agreement by and between the Registrant and Bristol Myers Squibb Company, dated December 7, 2020 (incorporated by reference to Exhibit 10.13 of the Registrant’s Annual Report on Form 10-K (File No. 333-239932) filed on March 29, 2021)
10.14#	Executive Employment Agreement by and between the Registrant and Alan Bash, dated February 1, 2022 (incorporated by reference to Exhibit 10.1 of the Registrant’s Current Report on Form 8-K (File No. 333-39425) filed on February 9, 2022)
21.1	List of Subsidiaries of the Registrant (incorporated by reference to Exhibit 21.1 of the Registrant’s Annual Report on Form 10K (File No. 333-239932) filed on March 29, 2021)
23.1*	Consent of KPMG LLP, independent registered public accounting firm
31.1*	Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as amended
31.2*	Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as amended
32.1+	Certification of Principal Executive Officer and Principal Financial Officer Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
101.INS*	Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCH*	Inline XBRL Taxonomy Extension Schema Document
101.CAL*	Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF*	Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB*	Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE*	Inline XBRL Taxonomy Extension Presentation Linkbase Document
104*	Cover Page Interactive Data File (formatted as inline XBRL with applicable taxonomy extension information contained in Exhibits 101.*)

# Indicates a management contract or any compensatory plan, contract or arrangement.

* Filed herewith.

** Confidential treatment has been granted by the Securities and Exchange Commission as to certain portions.

† Portions of this exhibit (indicated by asterisks) were omitted in accordance with the rules of the Securities and Exchange Commission.

+ The certifications furnished in Exhibit 32.1 hereto are deemed to be furnished with this Annual Report on Form 10-K and will not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, except to the extent that the Registrant specifically incorporates it by reference.

124

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

	CHECKMATE PHARMACEUTICALS, INC.
Date: March 29, 2022	By:	/s/ Alan Bash
		Alan Bash
		President and Chief Executive Officer
		(Principal Executive Officer)

POWER OF ATTORNEY

Each person whose individual signature appears below hereby authorizes and appoints Alan Bash and Robert Dolski, and each of them, with full power of substitution and resubstitution and full power to act without the other, as his or her true and lawful attorney-in-fact and agent to act in his or her name, place and stead and to execute in the name and on behalf of each person, individually and in each capacity stated below, and to file any and all amendments to this annual report on Form 10-K and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing, ratifying and confirming all that said attorneys-in-fact and agents or any of them or their or his substitute or substitutes may lawfully do or cause to be done by virtue thereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this Annual Report on Form 10-K has been signed by the following persons in the capacities indicated below and on the dates indicated:

Signature	Title	Date
/s/ Alan Bash Alan Bash	Chief Executive Officer, President and Director (Principal Executive Officer)	March 25, 2022
/s/ Robert Dolski Robert Dolski	Chief Financial Officer (Principal Financial and Accounting Officer)	March 25, 2022
/s/ Mike Powell Mike Powell	Director, Chairman	March 25, 2022
/s/ Peter Colabuono Peter Colabuono	Director	March 25, 2022
/s/ Keith Flaherty, M.D. Keith Flaherty, M.D.	Director	March 25, 2022
/s/ Alan Fuhrman Alan Fuhrman	Director	March 25, 2022
/s/ Oren K. Isacoff, M.D. Oren K. Isacoff, M.D.	Director	March 25, 2022
/s/ Joy Yan, M.D., Ph.D. Joy Yan, M.D., Ph.D.	Director	March 25, 2022
/s/ Jon Wigginton, M.D. Jon Wigginton, M.D.	Director	March 25, 2022

125

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

CONTENTS

Report of Independent Registered Public Accounting Firm	F-2
Financial Statements for the Years Ended December 31, 2021 and 2020:
Consolidated Balance Sheets	F-3
Consolidated Statements of Operations and Comprehensive Loss	F-4
Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity (Deficit)	F-5
Consolidated Statements of Cash Flows	F-6
Notes to Consolidated Financial Statements	F-7-F-21

F-1

Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors

Checkmate Pharmaceuticals, Inc.:

Opinion on the Consolidated Financial Statements

We have audited the accompanying consolidated balance sheets of Checkmate Pharmaceuticals, Inc. and subsidiary (the Company) as of December 31, 2021 and 2020, the related consolidated statements of operations and comprehensive loss, redeemable convertible preferred stock and stockholders’ equity (deficit), and cash flows for the years then ended, and the related notes (collectively, the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2021 and 2020, and the results of its operations and its cash flows for the years then ended, in conformity with U.S. generally accepted accounting principles.

Going Concern

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 2 to the consolidated financial statements, the Company has incurred recurring losses and negative cash flows from operations that raise substantial doubt about its ability to continue as a going concern. Management’s plans in regard to these matters are also described in Note 2. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

/s/ KPMG LLP

We have served as the Company’s auditor since 2019.

Boston, Massachusetts

March 29, 2022

F-2

CHECKMATE PHARMACEUTICALS, INC. AND SUBSIDIARY

CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share amounts)

	December 31,
	2021			2020
Assets
Current Assets:
Cash and cash equivalents	$	50,675		$	43,055
Restricted cash		20			20
Short-term investments		20,192			51,831
Prepaid expenses and other current assets		3,075			7,195
Total current assets		73,962			102,101
Investments, non-current		—			30,973
Equipment, net		777			—
Other assets		4,099			—
Total assets	$	78,838		$	133,074
Liabilities and Stockholders’ Equity
Current Liabilities:
Accounts payable	$	3,385		$	2,297
Accrued expenses		5,994			5,578
Total current liabilities		9,379			7,875
Total liabilities		9,379			7,875
Commitments and Contingencies (Note 12)
Stockholders’ Equity:
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of December 31, 2021 and 2020; no shares outstanding as of December 31, 2021 and 2020		—			—
Common stock, $0.0001 par value; 300,000,000 shares authorized as of December 31, 2021 and 2020; 21,630,572 and 21,560,398 shares issued and outstanding as of December 31, 2021 and 2020, respectively		2			2
Additional paid-in capital		270,947			265,342
Accumulated other comprehensive gain (loss)		(14	)		(74	)
Accumulated deficit		(201,476	)		(140,071	)
Total stockholders’ equity		69,459			125,199
Total liabilities and stockholders’ equity	$	78,838		$	133,074

The accompanying notes are an integral part of these consolidated financial statements.

F-3

CHECKMATE PHARMACEUTICALS, INC. AND SUBSIDIARY

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except share and per share amounts)

	Year ended December 31,
	2021			2020
Operating expenses:
Research and development	$	45,819		$	26,719
General and administrative		15,651			10,185
Total operating expenses		61,470			36,904
Loss from operations		(61,470	)		(36,904	)
Other income (expense):
Interest income		100			79
Loss on sale of available-for-sale investments		(35	)		—
Change in fair value of convertible notes		—			(83	)
Total other income (expense)		65			(4	)
Net loss	$	(61,405	)	$	(36,908	)
Reconciliation of net loss attributable to common stockholders:
Net loss	$	(61,405	)	$	(36,908	)
Accretion of issuance costs on redeemable convertible preferred stock		—			(461	)
Accrued dividends on redeemable convertible preferred stock		—			(5,536	)
Net loss attributable to common stockholders	$	(61,405	)	$	(42,905	)
Weighted-average common shares outstanding—basic and diluted		21,615,970			9,559,898
Net loss per share attributable to common stockholders—basic and diluted	$	(2.84	)	$	(4.49	)
Comprehensive loss:
Net loss	$	(61,405	)	$	(36,908	)
Unrealized gain (loss) on available-for-sale investments		60			(74	)
Comprehensive loss	$	(61,345	)	$	(36,982	)

The accompanying notes are an integral part of these consolidated financial statements.

F-4

CHECKMATE PHARMACEUTICALS, INC. AND SUBSIDIARY

CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY (DEFICIT)

(In thousands, except share and per share amounts)

	Series A Redeemable Convertible Preferred Stock						Series B Redeemable Convertible Preferred Stock						Series C Redeemable Convertible Preferred Stock						Common Stock				Additional Paid-In Capital			Accumulated Deficit			Accumulated Other Comprehensive Gain/(Loss)			Total Stockholders’ Equity (Deficit)
	Shares			Amount			Shares			Amount			Shares			Amount			Shares		Amount
Balances at December 31, 2019		25,000,000		$	32,482			26,283,386		$	64,446			—		$	—			1,488,489	$	1	$	—		$	(97,437	)		—		$	(97,436	)
Issuance of Series  B preferred stock at $2.1687 per share, net of issuance costs of $27		—			—			3,688,898			7,973			—			—			—		—		—			—			—			—
Exercise of Series B preferred stock tranche right		—			—			—			300			—			—			—		—		—			—			—			—
Issuance of Series C preferred stock at $1.6016 per share, net of issuance costs of $435		—			—			—			—			46,828,167			74,566			—		—		—			—			—			—
Conversion of convertible notes into Series C convertible preferred stock		—			—			—			—			6,295,756			10,083			—		—		—			—			—			—
Accretion of issuance costs related to redeemable convertible preferred stock		—			—			—			27			—			434			—		—		—			(461	)		—			(461	)
Accrued dividends on redeemable convertible preferred stock		—			1,222			—			3,152			—			1,162			—		—		(271	)		(5,265	)		—			(5,536	)
Conversion of redeemable convertible preferred stock to common stock		(25,000,000	)		(33,704	)		(29,972,284	)		(75,898	)		(53,123,923	)		(86,245	)		14,948,241		1		195,846			—			—			195,847
Exercise of stock options		—			—			—			—			—			—			13,807		—		20			—			—			20
Stock-based compensation expense		—			—			—			—			—			—			—		—		2,035			—			—			2,035
Issuance of common shares upon initial public offering net of issuance cost of $3,571		—			—			—			—			—			—			5,109,861		—		67,712			—						67,712
Unrealized loss on  available-for-sale investments		—			—			—			—			—			—			—		—		—			—			(74	)		(74	)
Net loss		—			—			—			—			—			—			—		—		—			(36,908	)		—			(36,908	)
Balances at December 31, 2020		—		$	—			—		$	—			—		$	—			21,560,398	$	2	$	265,342		$	(140,071	)		(74	)	$	125,199
Exercise of stock options		—			—			—			—			—			—			70,174		—		146			—			—			146
Stock-based compensation expense		—			—			—			—			—			—			—		—		5,459			—			—			5,459
Unrealized gain on available-for-sale investments		—			—			—			—			—			—			—		—		—			—			60			60
Net loss		—			—			—			—			—			—			—		—		—			(61,405	)		—			(61,405	)
Balances at December 31, 2021		—		$	—			—		$	—			—		$	—			21,630,572	$	2	$	270,947		$	(201,476	)		(14	)	$	69,459

The accompanying notes are an integral part of these consolidated financial statements.

5

CHECKMATE PHARMACEUTICALS, INC. AND SUBSIDIARY

CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

	Year ended December 31,
	2021			2020
Cash flows from operating activities
Net loss	$	(61,405	)	$	(36,908	)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock based compensation		5,459			2,035
Depreciation		66			—
Amortization/accretion of investments		691			188
Change in fair value of convertible notes		—			83
Loss on sale of available-for-sale investments		35			—
Change in operating assets and liabilities:
Prepaid expenses and other current assets		4,033			(6,049	)
Other assets		(4,099	)		—
Accounts payable		1,089			63
Accrued expenses		416			2,477
Net cash used in operating activities		(53,715	)		(38,111	)
Cash flows from investing activities
Purchases of investments		(10,239	)		(83,290	)
Maturities of investments		41,491			—
Sales of investments		30,780			—
Purchases equipment		(843	)		—
Net cash provided by (used in) investing activities		61,189			(83,290	)
Cash flows from financing activities
Proceeds from stock option exercises		146			20
Proceeds from issuance of convertible preferred stock, net		—			82,539
Proceeds from initial public offering of common stock, net		—			67,712
Proceeds from issuance of convertible notes		—			10,000
Net cash provided by financing activities		146			160,271
Net increase in cash, cash equivalents and restricted cash		7,620			38,870
Cash, cash equivalents and restricted cash at beginning of period		43,075			4,205
Cash, cash equivalents and restricted cash at end of period	$	50,695		$	43,075
Supplemental disclosure of non-cash financing activities:
Accretion of issuance costs related to redeemable convertible preferred stock	$	—		$	461
Exercise of Series B preferred stock tranche right	$	—		$	300
Accrued dividends on redeemable convertible preferred stock	$	—		$	5,536
Conversion of convertible notes into Series C preferred stock	$	—		$	10,083
Conversion of redeemable convertible preferred stock into common stock	$	—		$	195,847

The accompanying notes are an integral part of these consolidated financial statements.

F-6

CHECKMATE PHARMACEUTICALS, INC. AND SUBSIDIARY

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1 – NATURE OF BUSINESS

Nature of Business

Checkmate Pharmaceuticals, Inc. (“Checkmate” or the “Company”), headquartered in Cambridge, Massachusetts, is a clinical stage biotechnology company incorporated under the laws of the State of Delaware in July 2015 that is focused on developing and commercializing its proprietary technology to harness the power of the immune system to combat cancer. Since its inception, the Company has devoted substantially all of its efforts to the research and development activities, including recruiting management and technical staff, raising capital, producing materials for non-clinical and clinical studies and building infrastructure to support such activities, and has not yet generated any revenue. Expenses have primarily been for research and development and related administrative costs. The Company has financed its operations through the issuance of common and redeemable convertible preferred stock.

Initial Public Offering

On August 11, 2020, the Company completed an initial public offering of its common stock, at which time the Company issued and sold 5,000,000 shares of its common stock, at a price to the public of $15.00 per share. On September 3, 2020, the underwriters of the initial public offering exercised a portion of their overallotment option by purchasing an additional 109,861 shares from the Company at the initial public offering price. The Company received approximately $67.7 million in net proceeds, inclusive of the over-allotment exercise and after deducting underwriting discounts and commissions and other offering expenses payable by the Company.

In connection with the closing of the initial public offering, all outstanding shares of the Company’s redeemable convertible preferred stock were converted into 14,948,241 shares of the Company’s common stock. As a result of the conversion, the Company reclassified the carrying value of its preferred stock, which included all cumulative but unpaid dividends, to common stock and additional paid-in-capital and therefore there was no outstanding redeemable convertible preferred stock as of December 31, 2021 and 2020.

On July 31, 2020, the Company effected a one-for-7.4771 reverse stock split of its common stock. All shares, stock options, warrants, redeemable convertible preferred stock conversion prices, ratios and per share information presented in the consolidated financial statements have been adjusted to reflect the reverse stock split on a retroactive basis for all periods presented. The par value per share and the authorized number of shares of common stock were not adjusted as a result of the reverse stock split.

Risks and Uncertainties

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, the outcome of clinical trials, development by competitors of new therapeutics and technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations, ability to secure additional capital to fund operations, and risks associated with the ongoing COVID-19 global pandemic or future pandemics, including known and potential delays associated with its ongoing and anticipated trials and the Company’s ability to raise additional capital to finance its operations. There can be no assurance that the Company will be able to successfully complete the development of, or receive regulatory approval for, any products developed, and if approved, that any products will be commercially viable. Any products resulting from the Company’s current research and development efforts will require significant additional research and development, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel, infrastructure and extensive compliance reporting capabilities. The Company has not generated any revenues from the sale of any products to date. Even if the Company’s product

F-7

development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

2 – GOING CONCERN

Since inception, the Company has incurred recurring losses and negative cash flows from operations. The Company expects to continue to generate operating losses for the foreseeable future. The Company has funded its operations primarily with proceeds from the sale of its common stock, convertible debt and redeemable convertible preferred stock. The Company’s cash, cash equivalents and available-for-sale investments were $70.9 million as of December 31, 2021.

In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40), management is required to assess the Company’s ability to continue as a going concern within one year after the date that the consolidated financial statements are issued. The Company expects to seek additional funding to sustain its future operations through issuances of equity, licenses and other strategic collaborations. If the Company is unable to secure adequate additional funding, the Company may make reductions in certain expenditures. This may include delaying, reducing the scope of, suspending or eliminating one or more research and development or clinical programs.

As a result, management has concluded that substantial doubt exists with respect to the Company’s ability to continue as a going concern within one year after the date that these consolidated financial statements are issued. The Company expects its existing cash, cash equivalents and available-for-sale investments will be sufficient to fund its operating expenses and capital expenditure requirements through the end of 2022. The future viability of the Company beyond that point is dependent on its ability to raise additional capital to finance its operations. The accompanying consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. Accordingly, the consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and that contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

3 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation and Principles of Consolidation

The accompanying financial statements are prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and include the accounts of the Company and its wholly owned subsidiary Checkmate Pharmaceuticals Security Corporation. Any reference in these notes to applicable guidance is meant to refer to the authoritative accounting principles generally accepted in the United States as found in the Accounting Standard Codification (ASC) and ASU of the FASB.

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The Company bases estimates and assumptions on historical experience when available and on various factors that management believes to be reasonable under the circumstances. Significant estimates relied upon in preparing the accompanying financial statements include, but are not limited to the fair value of common stock used in the determination of stock-based compensation expense before the Company’s initial public offering of common stock, the valuation of derivative liabilities, the fair value of convertible notes and the accrual of research and development expenses. The Company assesses these estimates on an ongoing basis; however, actual results could differ materially from those estimates. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. The impact of changes in estimates are recorded in the period in which they become known.

F-8

Segment Information

The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. As of December 31, 2021 and 2020, all of the Company’s long-lived assets were domiciled in the United States.

Cash Equivalents

The Company considers all highly liquid investments purchased with remaining maturities of three months or less on the purchase date to be cash equivalents. The Company’s cash equivalents at December 31, 2021 and 2020 were $49.5 million and $8.8 million, respectively, and were comprised primarily of money market funds.

Restricted Cash

As of December 31, 2021 and 2020, the Company maintained a restricted cash balance of $20,000 relating to a corporate credit card account in a money market account.

Investments

The Company invests excess cash balances in commercial paper and corporate debt securities. The Company considers investments in commercial paper and corporate debt securities with an original maturity when purchased of greater than three months as available-for-sale. The Company reports available-for-sale investments at fair value at each balance sheet date, and includes any unrealized holding gains and losses in other comprehensive gain (loss), a component of stockholders’ equity. Realized gains and losses are determined using the specific-identification method, and are included in other (expense) income, net in its consolidated statements of operations and comprehensive loss. Should any adjustment to fair value reflect a decline in the value of the investment, the Company considers all available evidence to evaluate the extent to which the decline is “other than temporary” and, if so, recognizes the associated unrealized loss through a charge to the consolidated statements of operations and comprehensive loss. The Company did not record any impairment charges related to investments during the years ended December 31, 2021 and 2020.

The Company classifies available-for-sale investments as current or non-current based on each instrument’s underlying effective maturity date and for which it has the intent and ability to hold the investment for a period of greater than 12 months. Investments with maturities of less than 12 months are classified as current and are included in investments in the consolidated balance sheets. Investments with maturities greater than 12 months for which the Company has the intent and ability to hold the investment for greater than 12 months are classified as non-current and are included in investments, non-current in the consolidated balance sheets.

Equipment​​​​​​​

Equipment is recorded at cost less accumulated depreciation. Equipment is comprised of laboratory equipment and is being depreciated using the straight-line method over the estimated useful life of five years for each asset. Accumulated depreciation at December 31, 2021 was $0.1 million. Expenditures for repairs and maintenance are charged to expense as incurred. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in gain or loss from operations.

Impairment of long—lived assets​​​​​​​

Long-lived assets consist of machinery and equipment. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an

F-9

impairment review include significant negative industry or economic trends and significant changes or planned changes in the use of the assets. Recoverability is measured by comparing estimated undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the periods presented.​​​​​​​​​​​​​​

Redeemable Convertible Preferred Stock

The Company issued Series A redeemable convertible preferred stock (“Series A”), Series B redeemable convertible preferred stock (“Series B”) and Series C redeemable convertible preferred stock (“Series C”) under their respective stock purchase agreements. Series A, Series B and Series C are hereinafter individually and collectively referred to as “preferred stock”. Series A, Series B and Series C preferred stock were classified as temporary equity and were initially recorded at their original issuance price, net of issuance costs, initial tranche right liability and the intrinsic value of beneficial conversion feature, if any. The Company recognized changes in the redemption value of preferred stock as they occurred and accreted the carrying amount of preferred stock to its redemption value at the end of each reporting period. These increases were recorded as charges against retained earnings, if any, and then to additional paid-in capital. Then, in the absence of additional paid-in capital, the accretion was charged to the accumulated deficit.

Preferred Stock Tranche Right Liability

The Company classified preferred stock tranche rights as a liability on its balance sheet as each preferred stock tranche right was a freestanding financial instrument that required the Company to transfer assets upon the achievement of specified milestone events. The Company recorded a preferred stock tranche right liability initially at fair value upon the date of issuance of a preferred stock tranche right and subsequently remeasured to fair value at each reporting date. Changes in the fair value of a preferred stock tranche right liability were recognized as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. Changes in the fair value of a preferred stock tranche right liability were recognized until the respective preferred stock tranche right was settled upon achievement of the specified milestone event in January 2020.

Fair Value Measurements

Certain assets and liabilities of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

Level 3 — Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

F-10

Cash, cash equivalents, restricted cash and investments are reported at fair value based on Level 1 and Level 2 inputs (Note 3). Prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities.

The value of the convertible notes (Note 7) and Series B preferred stock tranche right liability (Note 8) were determined according to Level 3 inputs.

There were no transfers among the fair value hierarchy during the years ended December 31, 2021 and 2020.

Fair Value Option

As permitted under ASC 825, Financial Instruments (“ASC 825”), the Company elected the fair value option to account for its convertible notes. In accordance with ASC 825, the Company recorded these convertible notes at fair value with changes in fair value recorded as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. As a result of applying the fair value option, direct costs and fees related to the convertible notes were expensed as incurred and were not deferred. The Company concluded that it was appropriate to apply the fair value option to the convertible notes because there were no non-contingent beneficial conversion options related to the convertible notes.

Foreign Currency Transaction Gains or Losses

Transactions denominated in foreign currencies, which are primarily contract manufacturing services, are recorded in U.S. dollars on the date of those transactions. Adjustments arising from foreign currency transactions between the purchase and the settlement dates are reflected in the consolidated statements of operations and comprehensive loss as a component of operating expenses. The Company recorded foreign currency transaction gains of $18,000 and $0.1 million in the years ended December 31, 2021 and 2020, respectively, in the consolidated statements of operations.

Concentrations of Credit Risk and of Significant Suppliers

The Company has no significant off-balance sheet risk. Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents, restricted cash and investments. The Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality and has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company’s investment policy limits investment instruments to investment-grade securities with the objective to preserve capital and to maintain liquidity until the funds can be used in business operations.

The Company is dependent on third-party manufacturers to supply the drug substance and drug product for its research and development activities. These activities could be adversely affected by a significant interruption in the supply of such drug substance and drug product.

Net Loss per Share Attributable to Common Stockholders

For the year ended December 31, 2021, the Company calculated basic net loss per share by dividing the net loss by the weighted average number of common shares outstanding during the period.

For the year ended December 31, 2020, the Company followed the two-class method for computing net loss per share, as the Company had outstanding shares during that period that met the definition of participating securities. The two-class method determines net loss per share for each class of common and participating

F-11

securities according to dividends declared or accumulated and participation rights in undistributed earnings. Basic net loss per share is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding for the period without consideration for potentially dilutive securities. Net loss attributable to common stockholders is allocated to each share on an as-converted basis as if all of the net loss for the period had been distributed. During periods in which the Company incurred a net loss, the Company does not allocate net loss to participating securities because they do not have a contractual obligation to share in the net loss of the Company.

The Company computes diluted net loss per common share after giving consideration to all potentially dilutive common equivalents, including preferred stock, common stock options and common stock issuable under the Company’s employee stock purchase plan.

Basic and diluted net loss per share attributable to common stockholders was the same for all periods presented as the inclusion of all potentially dilutive securities outstanding was anti-dilutive. Options to purchase common stock at December 31, 2021 and 2020 of 3,169,418 and 2,537,669, respectively, have been excluded from the calculation of diluted net loss per share because their inclusion would have been antidilutive.

Research and Development

Research and development costs are expensed in the period incurred. Research and development costs include payroll and personnel expense; consulting costs; external contract research and development costs; raw materials; drug product manufacturing costs; and allocated overhead such as depreciation and amortization, rent and utilities. Advance payments for goods and services to be used in future research and development activities are recorded as prepaid expenses and are expensed over the service period as the services are provided or when the goods are consumed.

Clinical trial costs are a component of research and development expenses. The Company accrues and expenses clinical trial activities performed by third parties based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activation, and other information provided to the Company by its vendors.

Patent Costs

Costs to secure and maintain patents covering the Company’s technology and drug candidates are expensed as incurred and are classified as general and administrative expenses in the Company’s consolidated statements of operations.

Stock-Based Compensation

The Company issues stock-based awards to employees and non-employees, generally in the form of stock options. The Company accounts for its stock-based compensation awards in accordance with ASC 718, Compensation—Stock Compensation. The majority of the Company’s stock-based awards have been made to employees and board of director members. The Company measures compensation cost for all equity awards at their grant-date fair value and recognize compensation expense over the requisite service period, which is generally the vesting period, on a straight-line basis. The grant date fair value of stock options is estimated using the Black-Scholes option pricing model, which requires management to make assumptions with respect to the fair value of common stock on the grant date (for those stock options granted before the Company’s initial public offering), the expected term of the award, the expected volatility of the Company’ stock, calculated based on a period of time generally commensurate with the expected term of the award, risk-free interest rates and expected dividend yields of stock. The expected term of the Company’s stock options is determined utilizing the “simplified” method for awards that qualify as “plain vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. Forfeitures are accounted for as

F-12

they occur. Historically, for periods before the Company’s initial public offering, the fair value of the shares of common stock was determined on each grant date by the board of directors based on valuation estimates from management considering the most recently available independent third-party valuation of the Company’s common stock. The Company’s board of directors also assessed and considered, with input from management, additional objective and subjective factors that it believed were relevant and which may have changed from the date of the most recent valuation through the grant date. The Company classifies stock-based compensation expense in the consolidated statements of operations in the same manner in which the award recipient’s salary and related costs are classified or in which the award recipient’s service payments are classified.

Income Taxes

The Company accounts for income taxes using the asset and liability approach. Deferred tax assets and liabilities represent future tax consequences of temporary differences between the financial statement carrying amounts and the tax basis of assets and liabilities and for loss carryforwards using enacted tax rates expected to be in effect in the years in which the differences reverse. A valuation allowance is established to reduce deferred tax assets to the amounts expected to be realized. The Company also recognizes a tax benefit from uncertain tax positions only if it is “more likely than not” that the position is sustainable based on its technical merits. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. To date, the Company has not incurred interest and penalties related to uncertain tax positions. Should such costs be incurred, they would be classified as a component of provision for income taxes.

Emerging Growth Company Status

The Company is an “emerging growth company,” (EGC) as defined in the Jumpstart Our Business Startups Act, (JOBS Act), and may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not EGCs. The Company may take advantage of these exemptions until it is no longer an EGC under Section 107 of the JOBS Act and has elected to use the extended transition period for complying with new or revised accounting standards. As a result of this election, the Company’s financial statements may not be comparable to companies that comply with public company FASB standards’ effective dates. The Company may take advantage of these exemptions up until the last day of the fiscal year following the fifth anniversary of an offering or such earlier time that it is no longer an EGC.

Recently issued accounting pronouncements

In June 2016, the FASB issued ASU 2016-13, “Credit Losses (Topic 326).” ASU 2016-13 requires that financial assets measured at amortized cost, such as trade receivables and investments, be represented net of expected credit losses, which may be estimated based on relevant information such as historical experience, current conditions, and future expectation for each pool of similar financial asset. The new guidance requires enhanced disclosures related to trade receivables and associated credit losses. In May 2019, the FASB issued ASU No. 2019-05, “Financial Instruments—Credit Losses (Topic 326) Targeted Transition Relief,” which allows for a transition election on certain instruments. The guidance is effective for Small Reporting Companies for fiscal years beginning after December 15, 2022 and interim periods in those fiscal years. In November 2019, the FASB issued ASU No. 2019-11 which amends certain aspects of ASU No. 2016-13, including transition relief for trouble debt restructuring, among other topics. The Company is currently evaluating the impact of this pronouncement on its consolidated financial statements.

F-13

4 – FAIR VALUE MEASUREMENT

The following tables set forth the fair value of the Company’s financial assets and liabilities by level within the fair value hierarchy that are measured at fair value on a recurring basis:

	December 31, 2021
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets:
Money markets funds (included in cash equivalents)	$	49,482	$	—	$	—	$	49,482
Corporate debt securities		—		20,192		—		20,192
Total assets	$	49,482	$	20,192	$	—	$	69,674

	December 31, 2020
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets:
Money markets funds (included in cash equivalents)	$	7,839	$	—	$	—	$	7,839
Corporate debt securities		—		42,701		—		42,701
Commercial paper		—		41,103		—		41,103
Total assets	$	7,839	$	83,804	$	—	$	91,643

Marketable securities classified as Level 2 within the valuation hierarchy consist of commercial paper and corporate debt securities. The Company estimates the fair values of these marketable securities by taking into consideration valuations obtained from third-party pricing sources.

5 – INVESTMENTS

The following tables summarize the amortized cost and estimated fair value of the Company’s investments, which are considered to be available-for-sale investments as of December 31, 2021 and 2020:

As of December 31, 2021

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Short-term Investments		Investments, non-current
	(in thousands)
Corporate debt securities	$	20,206	$	—	$	(14	)	$	20,192	$	20,192	$	—

As of December 31, 2020

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Short-term Investments		Investments, non-current
	(in thousands)
Commercial paper	$	42,709	$	8	$	(16	)	$	42,701	$	42,701	$	—
Corporate debt securities		41,169		—		(66	)		41,103		10,130		30,973
Total	$	83,878	$	8	$	(82	)	$	83,804	$	52,831	$	30,973

At December 31, 2021, all available-for-sale investments had contractual maturities of one year or less, and there were no securities in the Company’s total investment portfolio that were in a continuous unrealized loss

F-14

position for more than 12 months. The Company concluded that the net declines in market value of available-for-sale securities were temporary in nature and did not consider any of investments to be other-than-temporarily impaired.

6 – ACCRUED EXPENSES

Accrued expenses consist of the following:

	December 31,
	2021		2020
	(in thousands)
Payroll and employee related expenses	$	2,499	$	1,555
External research and development		3,291		3,633
Other accrued expenses		204		390
Total accrued expenses	$	5,994	$	5,578

7 – CONVERTIBLE NOTES

On April 21, 2020, the Company entered into a note purchase agreement, pursuant to which the Company issued unsecured convertible notes to investors for a total of $10.0 million in principal.

On June 2, 2020, upon the Series C preferred stock financing, the outstanding principal and unpaid accrued interest of the convertible notes of $10.1 million converted into 6,295,756 shares of Series C preferred stock.

The change in fair value of the convertible notes prior to close of the Series C preferred stock financing of $0.1 million primarily related to the accrued interest earned on the convertible notes prior to such financing.

8 – REDEEMABLE CONVERTIBLE PREFERRED STOCK

As of December 31, 2021, the Company has 10,000,000 shares of undesignated preferred stock authorized. No shares of preferred stock have been issued.

As of December 31, 2019, the Company had 51,283,386 shares of preferred stock issued and outstanding, comprised of 25,000,000 shares designated as Series A preferred stock and 26,283,386 shares designated as Series B preferred stock.

In January 2020, the Company issued 3,688,898 shares of Series B preferred stock resulting in net proceeds received of $8.0 million.

In June 2020, the Company entered into a Series C preferred stock purchase agreement, pursuant to which the Company issued 46,828,167 shares of Series C preferred stock, resulting in net proceeds received of $74.6 million and an additional 6,295,756 shares of Series C preferred stock in satisfaction of the conversion of $10.0 million convertible notes and $0.1 million of accrued interest.

In connection with the Company’s IPO, all shares of preferred stock converted into 14,948,241 shares of common stock.

9 – COMMON STOCK

The voting, dividend and liquidation rights of the common stockholders are subject to and qualified by the rights, powers, and preferences of the preferred stock. The holders of the common stock are entitled to one vote

F-15

for each share of common stock held at all meetings of stockholders. Common stockholders are entitled to receive dividends declared out of funds legally available, subject to the payment in full of all preferential dividends to which the holders of preferred stock are entitled.

10 – STOCK-BASED COMPENSATION

Stock Options

In August 2015, the Company’s board of directors approved the Checkmate Pharmaceuticals, Inc. 2015 Stock Option and Grant Plan (the “2015 Plan”), to encourage and enable the officers, employees, directors, consultants and other key persons to acquire a proprietary interest in the Company. The 2015 Plan provided for the granting of incentive stock options, non-statutory stock options and restricted stock awards as determined by the board of directors.

In August 2020, the Company’s board of directors and stockholders adopted and approved the Checkmate Pharmaceuticals, Inc. 2020 Stock Option and Incentive Plan (the “2020 Plan”). The 2020 Plan allows for the issuance of stock awards in the form of options, stock appreciation rights, restricted stock awards, restricted stock units, unrestricted stock awards and cash-based awards to its officers, employees, non-employee directors and consultants of the Company. The maximum number of stock awards to be issued under the 2020 Plan is 4,797,421 shares, which is comprised of the initial limit of 3,205,430 shares, 729,575 shares that were remaining available for issuance under the Company’s 2015 Plan and 862,416 added to the 2020 Plan in 2021 by the Board of Directors in accordance with the Company’s “evergreen” provision. Under the terms of this provision, each January 1, beginning on January 1, 2021, the number of shares of stock reserved and available for issuance under the 2020 Plan shall be cumulatively increased by 4% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or such lesser number of shares as approved by the 2020 Plan administrator. Upon the creation of the 2020 Plan, no new stock awards will be issued from the 2015 Plan. Any awards granted from the 2015 Plan that are forfeited, canceled, or held back will be added back to shares issuable under the 2020 Plan. As of December 31, 2021, an aggregate of 2,617,066 shares of common stock was available for future grant.

The Company estimates the fair value of stock option awards on the grant date using the Black-Scholes option valuation model with the following weighted-average assumptions:

	Year ended December 31,
	2021			2020
Risk-free interest rate		0.94	%		0.31	%
Expected term (in years)		5.90			5.92
Expected volatility		83.02	%		78.84	%
Dividend yield		—			—

The per share weighted average grant date fair value of stock options granted during the years ended December 31, 2021 and 2020 was $6.46 and $14.50, respectively. As of December 31, 2021, total unrecognized compensation expense related to stock options totaled $11.4 million, which is expected to be recognized over a

F-16

weighted average period of 2.5 years. The following table summarizes the activity under the Company’s stock option plan during the year ended December 31, 2021:​​​​​​​

	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2020		2,537,669		$	9.61		8.2	$	13,177
Granted		1,484,433		$	9.28
Forfeited		(782,510	)	$	11.49
Exercised		(70,174	)	$	2.07
Outstanding at December 31, 2021		3,169,418		$	9.16		8.0	$	336
Vested and expected to vest at December 31, 2021		3,169,418		$	9.16		8.0	$	336
Exercisable at December 31, 2021		1,316,691		$	7.43		6.9	$	310

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock for those options that had exercise prices lower than the fair value of the Company’s common stock. The intrinsic value of options exercised during the year ended December 31, 2021 was $0.8 million.

Stock-based Compensation Expense

Total stock-based compensation expense was classified in the accompanying consolidated statements of operations as follows:

	Year ended December 31,
	2021		2020
	(in thousands)
Research and development	$	2,381	$	942
General and administrative		3,078		1,093
Total stock-based compensation expense	$	5,459	$	2,035

Employee Stock Purchase Plan

In July 2020, the Company’s board of directors and stockholders adopted and approved the Checkmate Pharmaceuticals, Inc. 2020 Employee Stock Purchase Plan (the “2020 ESPP”). The 2020 ESPP was created to provide eligible employees of the Company and other qualified participants to purchase the Company’s common stock at 85% of the fair market value of the common stock on the offering date or the exercise date, whichever is lower, for up to 15% of such employee’s compensation for each pay period. The Company reserved 267,119 shares of common stock for the 2020 ESPP. The 2020 ESPP provides for an annual increase in the number of shares of common stock to be reserved for future issuance under the 2020 ESPP. Each January 1, beginning on January 1, 2022, the number of shares of stock reserved and available for issuance under the 2020 ESPP shall be cumulatively increased by the lesser of (i) 267,119 shares of common stock, (ii) 1% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or (iii) such lesser number of shares of common stock as determined by the 2020 ESPP administrator. No shares of the Company’s common stock were purchased under the ESPP for the years ended December 31, 2021 and 2020.

F-17

11 – INCOME TAXES

For the year ended December 31, 2021 and 2020, the Company did not record a current or deferred income tax expense or benefit. The following table reconciles the federal statutory income rate to the Company’s effective income tax rate:​​​​​​​

	Year ended December 31,
	2021			2020
Tax at U.S. statutory rate		21.00	%		21.00	%
Changes from statutory rate:
State taxes, net of federal benefit		6.54	%		4.61	%
Non-deductible permanent items		(0.46	)%		—
Tax credits		6.12	%		1.97	%
Stock-based compensation		(0.51	)%		(1.11	)%
Change in valuation allowance		(32.69	)%		(26.47	)%
Effective income tax rate		0.00	%		0.00	%

​​​​​​​

The components of the Company’s deferred tax assets are as follows:

	Year ended December 31,
	2021			2020
	(in thousands)
Deferred tax assets
Net operating loss carryforwards	$	44,919		$	30,120
Tax credits		9,239			4,891
Stock-based compensation expenses		1,032			108
Accrued expenses and other		627			612
Gross deferred tax assets		55,817			35,731
Valuation allowance		(55,806	)		(35,731	)
Total deferred tax assets, net	$	11		$	—
Deferred tax liabilities
Depreciation and amortization	$	(11	)	$	—
Total deferred tax liabilities, net	$	(11	)	$	—
Net deferred tax asset (liability)	$	—		$	—

The Company has weighed the positive and negative evidence to assess the recoverability of its deferred tax assets. Realization of future tax benefits is dependent on many factors, including the Company’s ability to generate taxable income. After this assessment, the Company determined it was more likely than not that the Company will not realize the benefit of its deferred tax assets. As a result, the Company has provided a full valuation allowance against its net deferred tax assets. The valuation allowance for deferred tax assets as of December 31, 2021 and 2020 was $55.8 million and $35.7 million, respectively. For the years ended December 31, 2021 and 2020, the Company recorded a net valuation increase of $20.1 million and $9.8 million, respectively, primarily related to net operating losses (“NOLs”) and tax credits.

As of December 31, 2021, the Company had gross U.S. federal net operating loss carryforwards of $169.3 million including $138.0 million that had an indefinite carryforward period with utilization limited to 80% and $31.3 million that were subject to expiration at various dates through 2037. The Company had state net operating loss carryforwards of $147.9 million which will expire at various times through 2041. As of December 31, 2021, the Company had combined U.S. federal and state research and development tax credit

F-18

carryforwards of $12.2 million which will begin to expire in 2031. The net operating loss and research and development tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities.

Net operating loss and research and development tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes since its formation through December 31, 2021. The results of this study indicated that the Company experienced ownership changes as defined by Section 382 of the Code. The Company has identified approximately $1.3 million of NOLs that, as a result of these restrictions, will expire unused, and therefore have been excluded from the deferred tax assets in the table above.

The Company files income tax returns in the United States and various states. As of December 31, 2021, there are currently no income tax audits in progress. The federal and state income tax returns are generally subject to examinations for the tax years ended December 31, 2018 through December 31, 2021. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service or state tax authorities to the extent utilized in a future period.

The Company accounts for uncertainty in income taxes under the provisions of AC740 which defines the thresholds for recognizing the benefits of tax return positions in the consolidated financial statements as “more likely than not” to be sustained by the taxing authority. The tax benefit is measured based on the largest benefit that has a greater than 50% likelihood of being realized upon the ultimate settlement. As of December 31, 2021 and 2020, the Company has recorded $2.4 million and $1.3 million, respectively in unrecognized tax benefits. Any future interest and penalties related to income tax matters would be recognized in the provision for income tax. As of December 31, 2021 and 2020, no liability was recorded on the consolidated balance sheets for uncertain tax positions since the balance is fully offset by deferred tax assets, and the Company did not have a balance of accrued interest and penalties related to uncertain tax positions.

The following is reconciliation of the total amounts of unrecognized benefits:

	December 31,
	2021		2020
	(in thousands)
Unrecognized benefits at the beginning of the year	$	1,307	$	—
Additions for the tax positions related to the current year		1,126		1,307
Unrecognized benefits at the end of the year	$	2,433	$	1,307

12 – COMMITMENTS AND CONTINGENCIES

Operating Lease

The Company has a month-to-month lease agreement for its corporate space in Cambridge, Massachusetts. Rent expense is recognized as incurred. Rent expense for the years ended December 31, 2021 and 2020 was $0.6 million and $0.5 million, respectively.

F-19

Clinical Trial Collaboration and Supply Agreements

On May 10, 2021, the Company entered into a Supply and Non-Exclusive License Agreement (“SNLA”) with Regeneron Pharmaceuticals, Inc. (“Regeneron”). The SNLA dictates the general terms that govern specific collaborative studies between the Company and Regeneron, including a Phase 2 proof of concept trial, with patient cohorts in anti-PD-1 naïve and anti-PD-1 refractory cutaneous squamous cell carcinoma and anti-PD-1 refractory Merkel cell carcinoma. Pursuant to the SNLA, Regeneron agreed to provide cemiplimab, a drug to be used concurrently or in combination with vidutolimod in the aforementioned studies, at its own expense. As part of the SNLA, the parties granted each other non-exclusive licenses to use background intellectual property and regulatory documentation to seek regulatory approval of the other party’s compound solely for use as a combination therapy. The Company does not expect any future consideration to be payable to Regeneron pursuant to the SNLA.

On December 7, 2020, the Company entered into the Master Clinical Trial Collaboration Agreement (“MCTCA”) with Bristol-Myers Squibb Company (“BMS”). The MCTCA dictates the general terms that govern specific collaborative studies between the companies, including the Company’s Phase 2 refractory melanoma study and Phase 2 front-line melanoma study (collectively, the “collaborative studies”). Pursuant to the MCTCA, BMS agreed to provide nivolumab, a drug to be used in combination with vidutolimod in the collaborative studies, at its own expense. As part of the MCTCA, the parties granted each other non-exclusive licenses to use background intellectual property and regulatory documentation to seek regulatory approval of the other party’s compound solely for use as a combination therapy. The Company does not expect any further consideration to be payable to BMS pursuant to the MCTCA.

License Agreement

In June 2015, the Company entered into an exclusive license agreement with Cytos Biotechnology LTD (now Kuros Biosciences AG, or “Kuros”) as amended in August 2017 and as further amended in January 2018 (the “Kuros License Agreement”). Pursuant to the Kuros License Agreement, in return for payments made, the Company was granted an exclusive, royalty-bearing, sublicensable, worldwide license, under all of Kuros’ intellectual property rights, including any intellectual property rights arising during the term of the agreement, to commercially develop, manufacture, use, distribute, and sell certain therapeutic products, including vidutolimod, (the “Licensed Products”) for the diagnosis, treatment and prevention of all indications in humans and animals. Under the terms of the Kuros License Agreement, the Company is required to use commercially reasonable efforts to develop at least one Licensed Product. Under the Kuros License Agreement, the Company agreed to make payments to Kuros for each product that achieves certain development and regulatory milestones, including payments of up to $56.0 million for the Company’s current oncology programs. Through December 31, 2021, the Company has incurred license fees and milestone payments totaling $8.3 million, including $6.0 million in 2021. Cost incurred in 2021 relate to: (i) a $2.0 million milestone payment in connection with the dosing of the first patient in the Phase 2/3 first-line melanoma trial for vidutolimod and (ii) a $4.0 million milestone payment in connection with the patient dosing in a Phase 2 trial of vidutolimod in combination with nivolumab for the treatment of patients with anti-PD-1 refractory melanoma and to potentially support a Biologics License Application (“BLA”) and marketing approval of vidutolimod. Future milestone payments will be due upon filing for regulatory approval in each of the United States, Europe and the Far East and for ultimate approval in each of those regions.

The Company is also required to pay tiered royalties of high single-digit to low teens percentages on annual net sales of Licensed Products that are covered by a licensed patent, as well as royalties at 50% of the foregoing amounts with respect to sales of Licensed Products that are not covered by a licensed patent, but are covered by licensed know-how. The Kuros License Agreement expires upon the expiration of the last-to-expire royalty term for the Licensed Products in the territory. Either party has the right to terminate the agreement in full for an uncured material breach of the agreement upon written 60 days’ notice to the other party. The Company has the right to terminate the agreement for any reason upon 90 days’ written notice to Kuros.

F-20

Other Contingencies

During the ordinary course of its operations, the Company may become a party to contractual disputes, litigation, and potential claims. The Company does not believe that the resolution of any of these matters, if any, will have a material adverse effect on its financial position or results of operations.

13 – DEFINED CONTRIBUTION PLAN

The Company maintains a defined contribution plan under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”). The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pretax basis. The 401(k) Plan provides for matching contributions on a portion of participant contributions pursuant to the 401(k) Plan’s matching formula. The Company contributed $0.2 million and $0.1 million to the 401(k) Plan for the years ended December 31, 2021 and 2020, respectively

F-21

EX-23.1

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the registration statements (No. 333-254829) on Form S-8 and (No. 333-259353) on Form S-3 of our report dated March 29, 2022, with respect to the consolidated financial statements of Checkmate Pharmaceuticals, Inc. and subsidiary.

/s/ KPMG LLP

Boston, Massachusetts

March 29, 2022

EX-31.1

Exhibit 31.1

CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER PURSUANT TO RULES 13A-14 (A) AND

15D-14 (A) OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

I, Alan Bash, certify that:

1. I have reviewed this Annual Report on Form 10-K of Checkmate Pharmaceuticals, Inc.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant’s disclosure controls and procedures, and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: March 29, 2022

/s/ Alan Bash

Alan Bash

President and Chief Executive Officer

(Principal Executive Officer)

EX-31.2

Exhibit 31.2

CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER PURSUANT TO RULES 13A-14(A)

AND 15D-14(A) OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

I, Robert Dolski, certify that:

1. I have reviewed this Annual Report on Form 10-K of Checkmate Pharmaceuticals, Inc.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;c.Evaluated the effectiveness of the registrant’s disclosure controls and procedures, and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: March 29, 2022

/s/ Robert Dolski

Robert Dolski

Chief Financial Officer

(Principal Financial and Accounting Officer)

EX-32.1

Exhibit 32.1

CERTIFICATIONS OF PRINCIPAL EXECUTIVE OFFICER AND PRINCIPAL

FINANCIAL OFFICER PURSUANT TO 18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of Checkmate Pharmaceuticals, Inc. (the “Company”) on Form 10-K for the year ended December 31, 2021, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to the best of their knowledge:

1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

2) The information contained in the Report fairly presents, in all material respects, the financial condition of the Company and results of operations of the Company.

Date: March 29, 2022	/s/ Alan Bash
	Alan Bash
	President and Chief Executive Officer
	(Principal Executive Officer)

/s/ Robert Dolski

Robert Dolski

Chief Financial Officer

(Principal Financial and Accounting Officer)

XML

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2021	Mar. 29, 2022	Jun. 30, 2021
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Document Annual Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes
Entity Registrant Name	Checkmate Pharmaceuticals, Inc.
Entity Central Index Key	0001651431
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Shell Company	false
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Incorporation, State or Country Code	DE
Entity Address, State or Province	MA
Title of 12(b) Security	Common Stock
Trading Symbol	CMPI
Security Exchange Name	NASDAQ
Entity Public Float			$ 124,028,535
Entity Common Stock, Shares Outstanding		21,630,627
ICFR Auditor Attestation Flag	false
Entity File Number	001-39425
Entity Address, Address Line One	245 Main Street
Entity Address, Address Line Two	2nd Floor
Entity Address, City or Town	Cambridge
Entity Address, Postal Zip Code	02142
Entity Tax Identification Number	36-4813934
City Area Code	617
Local Phone Number	682-3625
Auditor Name	KPMG LLP
Auditor Firm ID	185
Auditor Location	Boston, Massachusetts

XML

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current Assets:
Cash and cash equivalents	$ 50,675	$ 43,055
Restricted cash	20	20
Short-term investments	20,192	51,831
Prepaid expenses and other current assets	3,075	7,195
Total current assets	73,962	102,101
Investments, non-current		30,973
Equipment, net	777
Other assets	4,099
Total assets	78,838	133,074
Current Liabilities:
Accounts payable	3,385	2,297
Accrued expenses	5,994	5,578
Total current liabilities	9,379	7,875
Total liabilities	9,379	7,875
Commitments and Contingencies (Note 12)
Stockholders' Equity:
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of December 31, 2021 and 2020; no shares outstanding as of December 31, 2021 and 2020	0	0
Common stock, $0.0001 par value; 300,000,000 shares authorized as of December 31, 2021 and 2020; 21,630,572 and 21,560,398 shares issued and outstanding as of December 31, 2021 and 2020, respectively	2	2
Additional paid-in capital	270,947	265,342
Accumulated other comprehensive gain (loss)	(14)	(74)
Accumulated deficit	(201,476)	(140,071)
Total stockholders' equity	69,459	125,199
Total liabilities and stockholders' equity	$ 78,838	$ 133,074

XML

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Common stock par value per share	$ 0.0001	$ 0.0001
Common stock number of shares authorised	300,000,000	300,000,000
Common stock number of shares issued	21,630,572	21,560,398
Common stock number of shares outstanding	21,630,572	21,560,398
Preferred stock par value per share	$ 0.0001	$ 0.0001
Preferred stock number of shares authorised	10,000,000	10,000,000
Preferred stock number of shares outstanding	0	0

XML

Consolidated Statements of Operations And Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating expenses:
Research and development	$ 45,819	$ 26,719
General and administrative	15,651	10,185
Total operating expenses	61,470	36,904
Loss from operations	(61,470)	(36,904)
Other income (expense):
Interest income	100	79
Loss on sale of available-for-sale investments	(35)
Change in fair value of convertible loan notes		(83)
Total other income (expense)	65	(4)
Net loss	(61,405)	(36,908)
Net loss	(61,405)	(36,908)
Accretion of issuance costs on redeemable convertible preferred stock		(461)
Accrued dividends on redeemable convertible preferred stock		(5,536)
Net loss attributable to common stockholders	$ (61,405)	$ (42,905)
Weighted-average common shares outstanding—basic and diluted	21,615,970	9,559,898
Net loss per share attributable to common stockholders—basic and diluted	$ (2.84)	$ (4.49)
Comprehensive loss:
Net loss	$ (61,405)	$ (36,908)
Unrealized gain (loss) on available-for-sale investments	60	(74)
Comprehensive loss	$ (61,345)	$ (36,982)

XML

Consolidated Statements of Redeemable Convertible Preferred Stock And Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Series A Redeemable Convertible Preferred Stock [Member]	Series B Redeemable Convertible Preferred Stock [Member]	Series C Redeemable Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Gain/(Loss) [Member]
Beginning balance at Dec. 31, 2019		$ 32,482	$ 64,446
Beginning balance, shares at Dec. 31, 2019	51,283,386	25,000,000	26,283,386
Beginning balance at Dec. 31, 2019	$ (97,436)				$ 1		$ (97,437)
Beginning balance, shares at Dec. 31, 2019					1,488,489
Issuance of series redeemable convertible preferred stock, net of issuance costs			$ 7,973	$ 74,566
Issuance of series redeemable convertible preferred stock, net of issuance costs, shares			3,688,898	46,828,167
Conversion of convertible loan notes into redeemable preferred stock				$ 10,083
Conversion of convertible loan notes into redeemable preferred stock, shares				6,295,756
Exercise of series B preferred stock tranche right	300		$ 300
Accretion of issuance costs related to redeemable convertible preferred stock	(461)		27	$ 434			(461)
Exercise of stock options	20					$ 20
Exercise of stock options, shares					13,807
Stock-based compensation expense	2,035					2,035
Accrued dividends on redeemable convertible preferred stock	5,536	$ 1,222	3,152	1,162		(271)	(5,265)
Conversion of redeemable convertible preferred stock	195,847	$ (33,704)	$ (75,898)	$ (86,245)	$ 1	195,846
Conversion of redeemable convertible preferred stock, shares		(25,000,000)	(29,972,284)	(53,123,923)	14,948,241
Issuance of common shares upon initial public offering net of issuance cost	67,712					$ 67,712
Issuance of common shares upon initial public offering net of issuance cost, shares					5,109,861
Unrealized gain on available-for-sale investments	(74)							$ (74)
Net loss	(36,908)						(36,908)
Ending balance at Dec. 31, 2020	$ 125,199				$ 2		(140,071)	(74)
Ending balance, shares at Dec. 31, 2020					21,560,398	265,342
Beginning balance, shares at Dec. 31, 2020	0
Exercise of stock options	$ 146					$ 146
Exercise of stock options, shares	70,174				70,174
Stock-based compensation expense	$ 5,459					$ 5,459
Unrealized gain on available-for-sale investments	60							60
Net loss	(61,405)						(61,405)
Ending balance at Dec. 31, 2021	$ 69,459				$ 2		$ (201,476)	$ (14)
Ending balance, shares at Dec. 31, 2021					21,630,572	270,947

XML

Consolidated Statements of Redeemable Convertible Preferred Stock And Stockholders' Equity (Deficit) (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares
IPO [Member]
Cash paid for redeemable convertible preferred stock issuance	$ 3,571
Series B Redeemable Convertible Preferred Stock [Member]
Shares Issued, Price Per Share | $ / shares	$ 2.1687
Cash paid for redeemable convertible preferred stock issuance	$ 27
Series C Redeemable Convertible Preferred Stock [Member]
Shares Issued, Price Per Share | $ / shares	$ 1.6016
Cash paid for redeemable convertible preferred stock issuance	$ 435

XML

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities
Net loss	$ (61,405)	$ (36,908)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock based compensation	5,459	2,035
Depreciation	66
Amortization/accretion of investments	691	188
Change in fair value of notes payable		83
Loss on sale of available-for-sale investments	35
Change in operating assets and liabilities:
Prepaid expenses and other current assets	4,033	(6,049)
Other assets	(4,099)
Accounts payable	1,089	63
Accrued expenses	416	2,477
Net cash used in operating activities	(53,715)	(38,111)
Cash flows from investing activities
Purchases of investments	(10,239)	(83,290)
Maturities of investments	41,491
Sale of investments	30,780
Purchases equipment	(843)
Net cash provided by (used in) investing activities	61,189	(83,290)
Cash flows from financing activities
Proceeds from stock option exercises	146	20
Proceeds from issuance of convertible preferred stock, net		82,539
Proceeds from initial public offering of common stock, net		67,712
Proceeds from issuance of convertible notes		10,000
Net cash provided by financing activities	146	160,271
Net increase in cash, cash equivalents and restricted cash	7,620	38,870
Cash, cash equivalents and restricted cash at beginning of period	43,075	4,205
Cash, cash equivalents and restricted cash at end of period	$ 50,695	43,075
Supplemental disclosure of non-cash investing and financing activities:
Accretion of issuance costs to redeemable convertible preferred stock		461
Exercise of Series B preferred stock tranche right		300
Accrued dividends on redeemable convertible preferred stock		5,536
Conversion of convertible notes into Series C preferred stock		10,083
Issuance of common stock upon conversion of redeemable convertible preferred stock		$ 195,847

XML

Nature of Business

12 Months Ended

Dec. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of Business

1 – NATURE OF BUSINESS

Nature of Business

Checkmate Pharmaceuticals, Inc. (“Checkmate” or the “Company”), headquartered in Cambridge, Massachusetts, is a clinical stage biotechnology company incorporated under the laws of the State of Delaware in July 2015 that is focused on developing and commercializing its proprietary technology to harness the power of the immune system to combat cancer. Since its inception, the Company has devoted substantially all of its efforts to the research and development activities, including recruiting management and technical staff, raising capital, producing materials for non-clinical and clinical studies and building infrastructure to support such activities, and has not yet generated any revenue. Expenses have primarily been for research and development and related administrative costs. The Company has financed its operations through the issuance of common and redeemable convertible preferred stock.

Initial Public Offering

On August 11, 2020, the Company completed an initial public offering of its common stock, at which time the Company issued and sold 5,000,000 shares of its common stock, at a price to the public of $15.00 per share. On September 3, 2020, the underwriters of the initial public offering exercised a portion of their overallotment option by purchasing an additional 109,861 shares from the Company at the initial public offering price. The Company received approximately $67.7 million in net proceeds, inclusive of the over-allotment exercise and after deducting underwriting discounts and commissions and other offering expenses payable by the Company.

In connection with the closing of the initial public offering, all outstanding shares of the Company’s redeemable convertible preferred stock were converted into 14,948,241 shares of the Company’s common stock. As a result of the conversion, the Company reclassified the carrying value of its preferred stock, which included all cumulative but unpaid dividends, to common stock and additional paid-in-capital and therefore there was no outstanding redeemable convertible preferred stock as of December 31, 2021 and 2020.

On July 31, 2020, the Company effected a one-for-7.4771 reverse stock split of its common stock. All shares, stock options, warrants, redeemable convertible preferred stock conversion prices, ratios and per share information presented in the consolidated financial statements have been adjusted to reflect the reverse stock split on a retroactive basis for all periods presented. The par value per share and the authorized number of shares of common stock were not adjusted as a result of the reverse stock split.

Risks and Uncertainties

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, the outcome of clinical trials, development by competitors of new therapeutics and technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations, ability to secure additional capital to fund operations, and risks associated with the ongoing COVID-19 global pandemic or future pandemics, including known and potential delays associated with its ongoing and anticipated trials and the Company’s ability to raise additional capital to finance its operations. There can be no assurance that the Company will be able to successfully complete the development of, or receive regulatory approval for, any products developed, and if approved, that any products will be commercially viable. Any products resulting from the Company’s current research and development efforts will require significant additional research and development, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel, infrastructure and extensive compliance reporting capabilities. The Company has not generated any revenues from the sale of any products to date. Even if the Company’s product

development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

XML

Going Concern

12 Months Ended

Dec. 31, 2021

Going Concern [Abstract]

Going Concern

2 – GOING CONCERN

Since inception, the Company has incurred recurring losses and negative cash flows from operations. The Company expects to continue to generate operating losses for the foreseeable future. The Company has funded its operations primarily with proceeds from the sale of its common stock, convertible debt and redeemable convertible preferred stock. The Company’s cash, cash equivalents and available-for-sale investments were $70.9 million as of December 31, 2021.

In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40), management is required to assess the Company’s ability to continue as a going concern within one year after the date that the consolidated financial statements are issued. The Company expects to seek additional funding to sustain its future operations through issuances of equity, licenses and other strategic collaborations. If the Company is unable to secure adequate additional funding, the Company may make reductions in certain expenditures. This may include delaying, reducing the scope of, suspending or eliminating one or more research and development or clinical programs.

As a result, management has concluded that substantial doubt exists with respect to the Company’s ability to continue as a going concern within one year after the date that these consolidated financial statements are issued. The Company expects its existing cash, cash equivalents and available-for-sale investments will be sufficient to fund its operating expenses and capital expenditure requirements through the end of 2022. The future viability of the Company beyond that point is dependent on its ability to raise additional capital to finance its operations. The accompanying consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. Accordingly, the consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and that contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

XML

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

3 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation and Principles of Consolidation

The accompanying financial statements are prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and include the accounts of the Company and its wholly owned subsidiary Checkmate Pharmaceuticals Security Corporation. Any reference in these notes to applicable guidance is meant to refer to the authoritative accounting principles generally accepted in the United States as found in the Accounting Standard Codification (ASC) and ASU of the FASB.

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The Company bases estimates and assumptions on historical experience when available and on various factors that management believes to be reasonable under the circumstances. Significant estimates relied upon in preparing the accompanying financial statements include, but are not limited to the fair value of common stock used in the determination of stock-based compensation expense before the Company’s initial public offering of common stock, the valuation of derivative liabilities, the fair value of convertible notes and the accrual of research and development expenses. The Company assesses these estimates on an ongoing basis; however, actual results could differ materially from those estimates. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. The impact of changes in estimates are recorded in the period in which they become known.

Segment Information

The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. As of December 31, 2021 and 2020, all of the Company’s long-lived assets were domiciled in the United States.

Cash Equivalents

The Company considers all highly liquid investments purchased with remaining maturities of three months or less on the purchase date to be cash equivalents. The Company’s cash equivalents at December 31, 2021 and 2020 were $49.5 million and $8.8 million, respectively, and were comprised primarily of money market funds.

Restricted Cash

As of December 31, 2021 and 2020, the Company maintained a restricted cash balance of $20,000 relating to a corporate credit card account in a money market account.

Investments

The Company invests excess cash balances in commercial paper and corporate debt securities. The Company considers investments in commercial paper and corporate debt securities with an original maturity when purchased of greater than three months as available-for-sale. The Company reports available-for-sale investments at fair value at each balance sheet date, and includes any unrealized holding gains and losses in other comprehensive gain (loss), a component of stockholders’ equity. Realized gains and losses are determined using the specific-identification method, and are included in other (expense) income, net in its consolidated statements of operations and comprehensive loss. Should any adjustment to fair value reflect a decline in the value of the investment, the Company considers all available evidence to evaluate the extent to which the decline is “other than temporary” and, if so, recognizes the associated unrealized loss through a charge to the consolidated statements of operations and comprehensive loss. The Company did not record any impairment charges related to investments during the years ended December 31, 2021 and 2020.

The Company classifies available-for-sale investments as current or non-current based on each instrument’s underlying effective maturity date and for which it has the intent and ability to hold the investment for a period of greater than 12 months. Investments with maturities of less than 12 months are classified as current and are included in investments in the consolidated balance sheets. Investments with maturities greater than 12 months for which the Company has the intent and ability to hold the investment for greater than 12 months are classified as non-current and are included in investments, non-current in the consolidated balance sheets.

Equipment​​​​​​​

Equipment is recorded at cost less accumulated depreciation. Equipment is comprised of laboratory equipment and is being depreciated using the straight-line method over the estimated useful life of five years for each asset. Accumulated depreciation at December 31, 2021 was $0.1 million. Expenditures for repairs and maintenance are charged to expense as incurred. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in gain or loss from operations.

Impairment of long—lived assets​​​​​​​

Long-lived assets consist of machinery and equipment. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an

impairment review include significant negative industry or economic trends and significant changes or planned changes in the use of the assets. Recoverability is measured by comparing estimated undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the periods presented.​​​​​​​​​​​​​​

Redeemable Convertible Preferred Stock

The Company issued Series A redeemable convertible preferred stock (“Series A”), Series B redeemable convertible preferred stock (“Series B”) and Series C redeemable convertible preferred stock (“Series C”) under their respective stock purchase agreements. Series A, Series B and Series C are hereinafter individually and collectively referred to as “preferred stock”. Series A, Series B and Series C preferred stock were classified as temporary equity and were initially recorded at their original issuance price, net of issuance costs, initial tranche right liability and the intrinsic value of beneficial conversion feature, if any. The Company recognized changes in the redemption value of preferred stock as they occurred and accreted the carrying amount of preferred stock to its redemption value at the end of each reporting period. These increases were recorded as charges against retained earnings, if any, and then to additional paid-in capital. Then, in the absence of additional paid-in capital, the accretion was charged to the accumulated deficit.

Preferred Stock Tranche Right Liability

The Company classified preferred stock tranche rights as a liability on its balance sheet as each preferred stock tranche right was a freestanding financial instrument that required the Company to transfer assets upon the achievement of specified milestone events. The Company recorded a preferred stock tranche right liability initially at fair value upon the date of issuance of a preferred stock tranche right and subsequently remeasured to fair value at each reporting date. Changes in the fair value of a preferred stock tranche right liability were recognized as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. Changes in the fair value of a preferred stock tranche right liability were recognized until the respective preferred stock tranche right was settled upon achievement of the specified milestone event in January 2020.

Fair Value Measurements

Certain assets and liabilities of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

Level 3 — Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

Cash, cash equivalents, restricted cash and investments are reported at fair value based on Level 1 and Level 2 inputs (Note 3). Prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities.

The value of the convertible notes (Note 7) and Series B preferred stock tranche right liability (Note 8) were determined according to Level 3 inputs.

There were no transfers among the fair value hierarchy during the years ended December 31, 2021 and 2020.

Fair Value Option

As permitted under ASC 825, Financial Instruments (“ASC 825”), the Company elected the fair value option to account for its convertible notes. In accordance with ASC 825, the Company recorded these convertible notes at fair value with changes in fair value recorded as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. As a result of applying the fair value option, direct costs and fees related to the convertible notes were expensed as incurred and were not deferred. The Company concluded that it was appropriate to apply the fair value option to the convertible notes because there were no non-contingent beneficial conversion options related to the convertible notes.

Foreign Currency Transaction Gains or Losses

Transactions denominated in foreign currencies, which are primarily contract manufacturing services, are recorded in U.S. dollars on the date of those transactions. Adjustments arising from foreign currency transactions between the purchase and the settlement dates are reflected in the consolidated statements of operations and comprehensive loss as a component of operating expenses. The Company recorded foreign currency transaction gains of $18,000 and $0.1 million in the years ended December 31, 2021 and 2020, respectively, in the consolidated statements of operations.

Concentrations of Credit Risk and of Significant Suppliers

The Company has no significant off-balance sheet risk. Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents, restricted cash and investments. The Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality and has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company’s investment policy limits investment instruments to investment-grade securities with the objective to preserve capital and to maintain liquidity until the funds can be used in business operations.

The Company is dependent on third-party manufacturers to supply the drug substance and drug product for its research and development activities. These activities could be adversely affected by a significant interruption in the supply of such drug substance and drug product.

Net Loss per Share Attributable to Common Stockholders

For the year ended December 31, 2021, the Company calculated basic net loss per share by dividing the net loss by the weighted average number of common shares outstanding during the period.

For the year ended December 31, 2020, the Company followed the two-class method for computing net loss per share, as the Company had outstanding shares during that period that met the definition of participating securities. The two-class method determines net loss per share for each class of common and participating

securities according to dividends declared or accumulated and participation rights in undistributed earnings. Basic net loss per share is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding for the period without consideration for potentially dilutive securities. Net loss attributable to common stockholders is allocated to each share on an as-converted basis as if all of the net loss for the period had been distributed. During periods in which the Company incurred a net loss, the Company does not allocate net loss to participating securities because they do not have a contractual obligation to share in the net loss of the Company.

The Company computes diluted net loss per common share after giving consideration to all potentially dilutive common equivalents, including preferred stock, common stock options and common stock issuable under the Company’s employee stock purchase plan.

Basic and diluted net loss per share attributable to common stockholders was the same for all periods presented as the inclusion of all potentially dilutive securities outstanding was anti-dilutive. Options to purchase common stock at December 31, 2021 and 2020 of 3,169,418 and 2,537,669, respectively, have been excluded from the calculation of diluted net loss per share because their inclusion would have been antidilutive.

Research and Development

Research and development costs are expensed in the period incurred. Research and development costs include payroll and personnel expense; consulting costs; external contract research and development costs; raw materials; drug product manufacturing costs; and allocated overhead such as depreciation and amortization, rent and utilities. Advance payments for goods and services to be used in future research and development activities are recorded as prepaid expenses and are expensed over the service period as the services are provided or when the goods are consumed.

Clinical trial costs are a component of research and development expenses. The Company accrues and expenses clinical trial activities performed by third parties based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activation, and other information provided to the Company by its vendors.

Patent Costs

Costs to secure and maintain patents covering the Company’s technology and drug candidates are expensed as incurred and are classified as general and administrative expenses in the Company’s consolidated statements of operations.

Stock-Based Compensation

The Company issues stock-based awards to employees and non-employees, generally in the form of stock options. The Company accounts for its stock-based compensation awards in accordance with ASC 718, Compensation—Stock Compensation. The majority of the Company’s stock-based awards have been made to employees and board of director members. The Company measures compensation cost for all equity awards at their grant-date fair value and recognize compensation expense over the requisite service period, which is generally the vesting period, on a straight-line basis. The grant date fair value of stock options is estimated using the Black-Scholes option pricing model, which requires management to make assumptions with respect to the fair value of common stock on the grant date (for those stock options granted before the Company’s initial public offering), the expected term of the award, the expected volatility of the Company’ stock, calculated based on a period of time generally commensurate with the expected term of the award, risk-free interest rates and expected dividend yields of stock. The expected term of the Company’s stock options is determined utilizing the “simplified” method for awards that qualify as “plain vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. Forfeitures are accounted for as

they occur. Historically, for periods before the Company’s initial public offering, the fair value of the shares of common stock was determined on each grant date by the board of directors based on valuation estimates from management considering the most recently available independent third-party valuation of the Company’s common stock. The Company’s board of directors also assessed and considered, with input from management, additional objective and subjective factors that it believed were relevant and which may have changed from the date of the most recent valuation through the grant date. The Company classifies stock-based compensation expense in the consolidated statements of operations in the same manner in which the award recipient’s salary and related costs are classified or in which the award recipient’s service payments are classified.

Income Taxes

The Company accounts for income taxes using the asset and liability approach. Deferred tax assets and liabilities represent future tax consequences of temporary differences between the financial statement carrying amounts and the tax basis of assets and liabilities and for loss carryforwards using enacted tax rates expected to be in effect in the years in which the differences reverse. A valuation allowance is established to reduce deferred tax assets to the amounts expected to be realized. The Company also recognizes a tax benefit from uncertain tax positions only if it is “more likely than not” that the position is sustainable based on its technical merits. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. To date, the Company has not incurred interest and penalties related to uncertain tax positions. Should such costs be incurred, they would be classified as a component of provision for income taxes.

Emerging Growth Company Status

The Company is an “emerging growth company,” (EGC) as defined in the Jumpstart Our Business Startups Act, (JOBS Act), and may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not EGCs. The Company may take advantage of these exemptions until it is no longer an EGC under Section 107 of the JOBS Act and has elected to use the extended transition period for complying with new or revised accounting standards. As a result of this election, the Company’s financial statements may not be comparable to companies that comply with public company FASB standards’ effective dates. The Company may take advantage of these exemptions up until the last day of the fiscal year following the fifth anniversary of an offering or such earlier time that it is no longer an EGC.

Recently issued accounting pronouncements

In June 2016, the FASB issued ASU 2016-13, “Credit Losses (Topic 326).” ASU 2016-13 requires that financial assets measured at amortized cost, such as trade receivables and investments, be represented net of expected credit losses, which may be estimated based on relevant information such as historical experience, current conditions, and future expectation for each pool of similar financial asset. The new guidance requires enhanced disclosures related to trade receivables and associated credit losses. In May 2019, the FASB issued ASU No. 2019-05, “Financial Instruments—Credit Losses (Topic 326) Targeted Transition Relief,” which allows for a transition election on certain instruments. The guidance is effective for Small Reporting Companies for fiscal years beginning after December 15, 2022 and interim periods in those fiscal years. In November 2019, the FASB issued ASU No. 2019-11 which amends certain aspects of ASU No. 2016-13, including transition relief for trouble debt restructuring, among other topics. The Company is currently evaluating the impact of this pronouncement on its consolidated financial statements.

XML

Fair Value Measurement

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurement

4 – FAIR VALUE MEASUREMENT

The following tables set forth the fair value of the Company’s financial assets and liabilities by level within the fair value hierarchy that are measured at fair value on a recurring basis:

	December 31, 2021
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets:
Money markets funds (included in cash equivalents)	$	49,482	$	—	$	—	$	49,482
Corporate debt securities		—		20,192		—		20,192
Total assets	$	49,482	$	20,192	$	—	$	69,674

	December 31, 2020
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets:
Money markets funds (included in cash equivalents)	$	7,839	$	—	$	—	$	7,839
Corporate debt securities		—		42,701		—		42,701
Commercial paper		—		41,103		—		41,103
Total assets	$	7,839	$	83,804	$	—	$	91,643

Marketable securities classified as Level 2 within the valuation hierarchy consist of commercial paper and corporate debt securities. The Company estimates the fair values of these marketable securities by taking into consideration valuations obtained from third-party pricing sources.

XML

Investments

12 Months Ended

Dec. 31, 2021

Investments, All Other Investments [Abstract]

Investments

5 – INVESTMENTS

The following tables summarize the amortized cost and estimated fair value of the Company’s investments, which are considered to be available-for-sale investments as of December 31, 2021 and 2020:

As of December 31, 2021

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Short-term Investments		Investments, non-current
	(in thousands)
Corporate debt securities	$	20,206	$	—	$	(14	)	$	20,192	$	20,192	$	—

As of December 31, 2020

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Short-term Investments		Investments, non-current
	(in thousands)
Commercial paper	$	42,709	$	8	$	(16	)	$	42,701	$	42,701	$	—
Corporate debt securities		41,169		—		(66	)		41,103		10,130		30,973
Total	$	83,878	$	8	$	(82	)	$	83,804	$	52,831	$	30,973

At December 31, 2021, all available-for-sale investments had contractual maturities of one year or less, and there were no securities in the Company’s total investment portfolio that were in a continuous unrealized loss

position for more than 12 months. The Company concluded that the net declines in market value of available-for-sale securities were temporary in nature and did not consider any of investments to be other-than-temporarily impaired.

XML

Accrued Expenses

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Accrued Expenses

6 – ACCRUED EXPENSES

Accrued expenses consist of the following:

	December 31,
	2021		2020
	(in thousands)
Payroll and employee related expenses	$	2,499	$	1,555
External research and development		3,291		3,633
Other accrued expenses		204		390
Total accrued expenses	$	5,994	$	5,578

XML

Convertible Notes

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Convertible Notes

7 – CONVERTIBLE NOTES

On April 21, 2020, the Company entered into a note purchase agreement, pursuant to which the Company issued unsecured convertible notes to investors for a total of $10.0 million in principal.

On June 2, 2020, upon the Series C preferred stock financing, the outstanding principal and unpaid accrued interest of the convertible notes of $10.1 million converted into 6,295,756 shares of Series C preferred stock.

The change in fair value of the convertible notes prior to close of the Series C preferred stock financing of $0.1 million primarily related to the accrued interest earned on the convertible notes prior to such financing.

XML

Redeemable Convertible Preferred Stock

12 Months Ended

Dec. 31, 2021

Temporary Equity Disclosure [Abstract]

Redeemable Convertible Preferred Stock

8 – REDEEMABLE CONVERTIBLE PREFERRED STOCK

As of December 31, 2021, the Company has 10,000,000 shares of undesignated preferred stock authorized. No shares of preferred stock have been issued.

As of December 31, 2019, the Company had 51,283,386 shares of preferred stock issued and outstanding, comprised of 25,000,000 shares designated as Series A preferred stock and 26,283,386 shares designated as Series B preferred stock.

In January 2020, the Company issued 3,688,898 shares of Series B preferred stock resulting in net proceeds received of $8.0 million.

In June 2020, the Company entered into a Series C preferred stock purchase agreement, pursuant to which the Company issued 46,828,167 shares of Series C preferred stock, resulting in net proceeds received of $74.6 million and an additional 6,295,756 shares of Series C preferred stock in satisfaction of the conversion of $10.0 million convertible notes and $0.1 million of accrued interest.

In connection with the Company’s IPO, all shares of preferred stock converted into 14,948,241 shares of common stock.

XML

Common Stock

12 Months Ended

Dec. 31, 2021

Equity [Abstract]

Common Stock

9 – COMMON STOCK

The voting, dividend and liquidation rights of the common stockholders are subject to and qualified by the rights, powers, and preferences of the preferred stock. The holders of the common stock are entitled to one vote

for each share of common stock held at all meetings of stockholders. Common stockholders are entitled to receive dividends declared out of funds legally available, subject to the payment in full of all preferential dividends to which the holders of preferred stock are entitled.

XML

Stock-Based Compensation

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation

10 – STOCK-BASED COMPENSATION

Stock Options

In August 2015, the Company’s board of directors approved the Checkmate Pharmaceuticals, Inc. 2015 Stock Option and Grant Plan (the “2015 Plan”), to encourage and enable the officers, employees, directors, consultants and other key persons to acquire a proprietary interest in the Company. The 2015 Plan provided for the granting of incentive stock options, non-statutory stock options and restricted stock awards as determined by the board of directors.

In August 2020, the Company’s board of directors and stockholders adopted and approved the Checkmate Pharmaceuticals, Inc. 2020 Stock Option and Incentive Plan (the “2020 Plan”). The 2020 Plan allows for the issuance of stock awards in the form of options, stock appreciation rights, restricted stock awards, restricted stock units, unrestricted stock awards and cash-based awards to its officers, employees, non-employee directors and consultants of the Company. The maximum number of stock awards to be issued under the 2020 Plan is 4,797,421 shares, which is comprised of the initial limit of 3,205,430 shares, 729,575 shares that were remaining available for issuance under the Company’s 2015 Plan and 862,416 added to the 2020 Plan in 2021 by the Board of Directors in accordance with the Company’s “evergreen” provision. Under the terms of this provision, each January 1, beginning on January 1, 2021, the number of shares of stock reserved and available for issuance under the 2020 Plan shall be cumulatively increased by 4% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or such lesser number of shares as approved by the 2020 Plan administrator. Upon the creation of the 2020 Plan, no new stock awards will be issued from the 2015 Plan. Any awards granted from the 2015 Plan that are forfeited, canceled, or held back will be added back to shares issuable under the 2020 Plan. As of December 31, 2021, an aggregate of 2,617,066 shares of common stock was available for future grant.

The Company estimates the fair value of stock option awards on the grant date using the Black-Scholes option valuation model with the following weighted-average assumptions:

	Year ended December 31,
	2021			2020
Risk-free interest rate		0.94	%		0.31	%
Expected term (in years)		5.90			5.92
Expected volatility		83.02	%		78.84	%
Dividend yield		—			—

The per share weighted average grant date fair value of stock options granted during the years ended December 31, 2021 and 2020 was $6.46 and $14.50, respectively. As of December 31, 2021, total unrecognized compensation expense related to stock options totaled $11.4 million, which is expected to be recognized over a

weighted average period of 2.5 years. The following table summarizes the activity under the Company’s stock option plan during the year ended December 31, 2021:​​​​​​​

	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2020		2,537,669		$	9.61		8.2	$	13,177
Granted		1,484,433		$	9.28
Forfeited		(782,510	)	$	11.49
Exercised		(70,174	)	$	2.07
Outstanding at December 31, 2021		3,169,418		$	9.16		8.0	$	336
Vested and expected to vest at December 31, 2021		3,169,418		$	9.16		8.0	$	336
Exercisable at December 31, 2021		1,316,691		$	7.43		6.9	$	310

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock for those options that had exercise prices lower than the fair value of the Company’s common stock. The intrinsic value of options exercised during the year ended December 31, 2021 was $0.8 million.

Stock-based Compensation Expense

Total stock-based compensation expense was classified in the accompanying consolidated statements of operations as follows:

	Year ended December 31,
	2021		2020
	(in thousands)
Research and development	$	2,381	$	942
General and administrative		3,078		1,093
Total stock-based compensation expense	$	5,459	$	2,035

Employee Stock Purchase Plan

In July 2020, the Company’s board of directors and stockholders adopted and approved the Checkmate Pharmaceuticals, Inc. 2020 Employee Stock Purchase Plan (the “2020 ESPP”). The 2020 ESPP was created to provide eligible employees of the Company and other qualified participants to purchase the Company’s common stock at 85% of the fair market value of the common stock on the offering date or the exercise date, whichever is lower, for up to 15% of such employee’s compensation for each pay period. The Company reserved 267,119 shares of common stock for the 2020 ESPP. The 2020 ESPP provides for an annual increase in the number of shares of common stock to be reserved for future issuance under the 2020 ESPP. Each January 1, beginning on January 1, 2022, the number of shares of stock reserved and available for issuance under the 2020 ESPP shall be cumulatively increased by the lesser of (i) 267,119 shares of common stock, (ii) 1% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or (iii) such lesser number of shares of common stock as determined by the 2020 ESPP administrator. No shares of the Company’s common stock were purchased under the ESPP for the years ended December 31, 2021 and 2020.

XML

Income taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income taxes

11 – INCOME TAXES

For the year ended December 31, 2021 and 2020, the Company did not record a current or deferred income tax expense or benefit. The following table reconciles the federal statutory income rate to the Company’s effective income tax rate:​​​​​​​

	Year ended December 31,
	2021			2020
Tax at U.S. statutory rate		21.00	%		21.00	%
Changes from statutory rate:
State taxes, net of federal benefit		6.54	%		4.61	%
Non-deductible permanent items		(0.46	)%		—
Tax credits		6.12	%		1.97	%
Stock-based compensation		(0.51	)%		(1.11	)%
Change in valuation allowance		(32.69	)%		(26.47	)%
Effective income tax rate		0.00	%		0.00	%

​​​​​​​

The components of the Company’s deferred tax assets are as follows:

	Year ended December 31,
	2021			2020
	(in thousands)
Deferred tax assets
Net operating loss carryforwards	$	44,919		$	30,120
Tax credits		9,239			4,891
Stock-based compensation expenses		1,032			108
Accrued expenses and other		627			612
Gross deferred tax assets		55,817			35,731
Valuation allowance		(55,806	)		(35,731	)
Total deferred tax assets, net	$	11		$	—
Deferred tax liabilities
Depreciation and amortization	$	(11	)	$	—
Total deferred tax liabilities, net	$	(11	)	$	—
Net deferred tax asset (liability)	$	—		$	—

The Company has weighed the positive and negative evidence to assess the recoverability of its deferred tax assets. Realization of future tax benefits is dependent on many factors, including the Company’s ability to generate taxable income. After this assessment, the Company determined it was more likely than not that the Company will not realize the benefit of its deferred tax assets. As a result, the Company has provided a full valuation allowance against its net deferred tax assets. The valuation allowance for deferred tax assets as of December 31, 2021 and 2020 was $55.8 million and $35.7 million, respectively. For the years ended December 31, 2021 and 2020, the Company recorded a net valuation increase of $20.1 million and $9.8 million, respectively, primarily related to net operating losses (“NOLs”) and tax credits.

As of December 31, 2021, the Company had gross U.S. federal net operating loss carryforwards of $169.3 million including $138.0 million that had an indefinite carryforward period with utilization limited to 80% and $31.3 million that were subject to expiration at various dates through 2037. The Company had state net operating loss carryforwards of $147.9 million which will expire at various times through 2041. As of December 31, 2021, the Company had combined U.S. federal and state research and development tax credit

carryforwards of $12.2 million which will begin to expire in 2031. The net operating loss and research and development tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities.

Net operating loss and research and development tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes since its formation through December 31, 2021. The results of this study indicated that the Company experienced ownership changes as defined by Section 382 of the Code. The Company has identified approximately $1.3 million of NOLs that, as a result of these restrictions, will expire unused, and therefore have been excluded from the deferred tax assets in the table above.

The Company files income tax returns in the United States and various states. As of December 31, 2021, there are currently no income tax audits in progress. The federal and state income tax returns are generally subject to examinations for the tax years ended December 31, 2018 through December 31, 2021. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service or state tax authorities to the extent utilized in a future period.

The Company accounts for uncertainty in income taxes under the provisions of AC740 which defines the thresholds for recognizing the benefits of tax return positions in the consolidated financial statements as “more likely than not” to be sustained by the taxing authority. The tax benefit is measured based on the largest benefit that has a greater than 50% likelihood of being realized upon the ultimate settlement. As of December 31, 2021 and 2020, the Company has recorded $2.4 million and $1.3 million, respectively in unrecognized tax benefits. Any future interest and penalties related to income tax matters would be recognized in the provision for income tax. As of December 31, 2021 and 2020, no liability was recorded on the consolidated balance sheets for uncertain tax positions since the balance is fully offset by deferred tax assets, and the Company did not have a balance of accrued interest and penalties related to uncertain tax positions.

The following is reconciliation of the total amounts of unrecognized benefits:

	December 31,
	2021		2020
	(in thousands)
Unrecognized benefits at the beginning of the year	$	1,307	$	—
Additions for the tax positions related to the current year		1,126		1,307
Unrecognized benefits at the end of the year	$	2,433	$	1,307

XML

Commitments And Contingencies

12 Months Ended

Dec. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Commitments And Contingencies

12 – COMMITMENTS AND CONTINGENCIES

Operating Lease

The Company has a month-to-month lease agreement for its corporate space in Cambridge, Massachusetts. Rent expense is recognized as incurred. Rent expense for the years ended December 31, 2021 and 2020 was $0.6 million and $0.5 million, respectively.

Clinical Trial Collaboration and Supply Agreements

On May 10, 2021, the Company entered into a Supply and Non-Exclusive License Agreement (“SNLA”) with Regeneron Pharmaceuticals, Inc. (“Regeneron”). The SNLA dictates the general terms that govern specific collaborative studies between the Company and Regeneron, including a Phase 2 proof of concept trial, with patient cohorts in anti-PD-1 naïve and anti-PD-1 refractory cutaneous squamous cell carcinoma and anti-PD-1 refractory Merkel cell carcinoma. Pursuant to the SNLA, Regeneron agreed to provide cemiplimab, a drug to be used concurrently or in combination with vidutolimod in the aforementioned studies, at its own expense. As part of the SNLA, the parties granted each other non-exclusive licenses to use background intellectual property and regulatory documentation to seek regulatory approval of the other party’s compound solely for use as a combination therapy. The Company does not expect any future consideration to be payable to Regeneron pursuant to the SNLA.

On December 7, 2020, the Company entered into the Master Clinical Trial Collaboration Agreement (“MCTCA”) with Bristol-Myers Squibb Company (“BMS”). The MCTCA dictates the general terms that govern specific collaborative studies between the companies, including the Company’s Phase 2 refractory melanoma study and Phase 2 front-line melanoma study (collectively, the “collaborative studies”). Pursuant to the MCTCA, BMS agreed to provide nivolumab, a drug to be used in combination with vidutolimod in the collaborative studies, at its own expense. As part of the MCTCA, the parties granted each other non-exclusive licenses to use background intellectual property and regulatory documentation to seek regulatory approval of the other party’s compound solely for use as a combination therapy. The Company does not expect any further consideration to be payable to BMS pursuant to the MCTCA.

License Agreement

In June 2015, the Company entered into an exclusive license agreement with Cytos Biotechnology LTD (now Kuros Biosciences AG, or “Kuros”) as amended in August 2017 and as further amended in January 2018 (the “Kuros License Agreement”). Pursuant to the Kuros License Agreement, in return for payments made, the Company was granted an exclusive, royalty-bearing, sublicensable, worldwide license, under all of Kuros’ intellectual property rights, including any intellectual property rights arising during the term of the agreement, to commercially develop, manufacture, use, distribute, and sell certain therapeutic products, including vidutolimod, (the “Licensed Products”) for the diagnosis, treatment and prevention of all indications in humans and animals. Under the terms of the Kuros License Agreement, the Company is required to use commercially reasonable efforts to develop at least one Licensed Product. Under the Kuros License Agreement, the Company agreed to make payments to Kuros for each product that achieves certain development and regulatory milestones, including payments of up to $56.0 million for the Company’s current oncology programs. Through December 31, 2021, the Company has incurred license fees and milestone payments totaling $8.3 million, including $6.0 million in 2021. Cost incurred in 2021 relate to: (i) a $2.0 million milestone payment in connection with the dosing of the first patient in the Phase 2/3 first-line melanoma trial for vidutolimod and (ii) a $4.0 million milestone payment in connection with the patient dosing in a Phase 2 trial of vidutolimod in combination with nivolumab for the treatment of patients with anti-PD-1 refractory melanoma and to potentially support a Biologics License Application (“BLA”) and marketing approval of vidutolimod. Future milestone payments will be due upon filing for regulatory approval in each of the United States, Europe and the Far East and for ultimate approval in each of those regions.

The Company is also required to pay tiered royalties of high single-digit to low teens percentages on annual net sales of Licensed Products that are covered by a licensed patent, as well as royalties at 50% of the foregoing amounts with respect to sales of Licensed Products that are not covered by a licensed patent, but are covered by licensed know-how. The Kuros License Agreement expires upon the expiration of the last-to-expire royalty term for the Licensed Products in the territory. Either party has the right to terminate the agreement in full for an uncured material breach of the agreement upon written 60 days’ notice to the other party. The Company has the right to terminate the agreement for any reason upon 90 days’ written notice to Kuros.

Other Contingencies

During the ordinary course of its operations, the Company may become a party to contractual disputes, litigation, and potential claims. The Company does not believe that the resolution of any of these matters, if any, will have a material adverse effect on its financial position or results of operations.

XML

Defined Contribution Plan

12 Months Ended

Dec. 31, 2021

Retirement Benefits [Abstract]

Defined Contribution Plan

13 – DEFINED CONTRIBUTION PLAN

The Company maintains a defined contribution plan under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”). The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pretax basis. The 401(k) Plan provides for matching contributions on a portion of participant contributions pursuant to the 401(k) Plan’s matching formula. The Company contributed $0.2 million and $0.1 million to the 401(k) Plan for the years ended December 31, 2021 and 2020, respectively

XML

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Basis of Presentation and Principles of Consolidation

Basis of Presentation and Principles of Consolidation

The accompanying financial statements are prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and include the accounts of the Company and its wholly owned subsidiary Checkmate Pharmaceuticals Security Corporation. Any reference in these notes to applicable guidance is meant to refer to the authoritative accounting principles generally accepted in the United States as found in the Accounting Standard Codification (ASC) and ASU of the FASB.

Use of Estimates

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The Company bases estimates and assumptions on historical experience when available and on various factors that management believes to be reasonable under the circumstances. Significant estimates relied upon in preparing the accompanying financial statements include, but are not limited to the fair value of common stock used in the determination of stock-based compensation expense before the Company’s initial public offering of common stock, the valuation of derivative liabilities, the fair value of convertible notes and the accrual of research and development expenses. The Company assesses these estimates on an ongoing basis; however, actual results could differ materially from those estimates. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. The impact of changes in estimates are recorded in the period in which they become known.

Segment Information

Segment Information

The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. As of December 31, 2021 and 2020, all of the Company’s long-lived assets were domiciled in the United States.

Cash Equivalents

Cash Equivalents

The Company considers all highly liquid investments purchased with remaining maturities of three months or less on the purchase date to be cash equivalents. The Company’s cash equivalents at December 31, 2021 and 2020 were $49.5 million and $8.8 million, respectively, and were comprised primarily of money market funds.

Restricted Cash

Restricted Cash

As of December 31, 2021 and 2020, the Company maintained a restricted cash balance of $20,000 relating to a corporate credit card account in a money market account.

Investments

Investments

The Company invests excess cash balances in commercial paper and corporate debt securities. The Company considers investments in commercial paper and corporate debt securities with an original maturity when purchased of greater than three months as available-for-sale. The Company reports available-for-sale investments at fair value at each balance sheet date, and includes any unrealized holding gains and losses in other comprehensive gain (loss), a component of stockholders’ equity. Realized gains and losses are determined using the specific-identification method, and are included in other (expense) income, net in its consolidated statements of operations and comprehensive loss. Should any adjustment to fair value reflect a decline in the value of the investment, the Company considers all available evidence to evaluate the extent to which the decline is “other than temporary” and, if so, recognizes the associated unrealized loss through a charge to the consolidated statements of operations and comprehensive loss. The Company did not record any impairment charges related to investments during the years ended December 31, 2021 and 2020.

The Company classifies available-for-sale investments as current or non-current based on each instrument’s underlying effective maturity date and for which it has the intent and ability to hold the investment for a period of greater than 12 months. Investments with maturities of less than 12 months are classified as current and are included in investments in the consolidated balance sheets. Investments with maturities greater than 12 months for which the Company has the intent and ability to hold the investment for greater than 12 months are classified as non-current and are included in investments, non-current in the consolidated balance sheets.

Equipment

Equipment​​​​​​​

Equipment is recorded at cost less accumulated depreciation. Equipment is comprised of laboratory equipment and is being depreciated using the straight-line method over the estimated useful life of five years for each asset. Accumulated depreciation at December 31, 2021 was $0.1 million. Expenditures for repairs and maintenance are charged to expense as incurred. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in gain or loss from operations.

Impairment of long—lived assets

Impairment of long—lived assets​​​​​​​

Long-lived assets consist of machinery and equipment. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an

impairment review include significant negative industry or economic trends and significant changes or planned changes in the use of the assets. Recoverability is measured by comparing estimated undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the periods presented.​​​​​​​

Redeemable Convertible Preferred Stock

Redeemable Convertible Preferred Stock

The Company issued Series A redeemable convertible preferred stock (“Series A”), Series B redeemable convertible preferred stock (“Series B”) and Series C redeemable convertible preferred stock (“Series C”) under their respective stock purchase agreements. Series A, Series B and Series C are hereinafter individually and collectively referred to as “preferred stock”. Series A, Series B and Series C preferred stock were classified as temporary equity and were initially recorded at their original issuance price, net of issuance costs, initial tranche right liability and the intrinsic value of beneficial conversion feature, if any. The Company recognized changes in the redemption value of preferred stock as they occurred and accreted the carrying amount of preferred stock to its redemption value at the end of each reporting period. These increases were recorded as charges against retained earnings, if any, and then to additional paid-in capital. Then, in the absence of additional paid-in capital, the accretion was charged to the accumulated deficit.

Preferred Stock Tranche Right Liability

Preferred Stock Tranche Right Liability

The Company classified preferred stock tranche rights as a liability on its balance sheet as each preferred stock tranche right was a freestanding financial instrument that required the Company to transfer assets upon the achievement of specified milestone events. The Company recorded a preferred stock tranche right liability initially at fair value upon the date of issuance of a preferred stock tranche right and subsequently remeasured to fair value at each reporting date. Changes in the fair value of a preferred stock tranche right liability were recognized as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. Changes in the fair value of a preferred stock tranche right liability were recognized until the respective preferred stock tranche right was settled upon achievement of the specified milestone event in January 2020.

Fair Value Measurements

Fair Value Measurements

Certain assets and liabilities of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

Level 3 — Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

Cash, cash equivalents, restricted cash and investments are reported at fair value based on Level 1 and Level 2 inputs (Note 3). Prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities.

The value of the convertible notes (Note 7) and Series B preferred stock tranche right liability (Note 8) were determined according to Level 3 inputs.

There were no transfers among the fair value hierarchy during the years ended December 31, 2021 and 2020.

Fair Value Option

Fair Value Option

As permitted under ASC 825, Financial Instruments (“ASC 825”), the Company elected the fair value option to account for its convertible notes. In accordance with ASC 825, the Company recorded these convertible notes at fair value with changes in fair value recorded as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. As a result of applying the fair value option, direct costs and fees related to the convertible notes were expensed as incurred and were not deferred. The Company concluded that it was appropriate to apply the fair value option to the convertible notes because there were no non-contingent beneficial conversion options related to the convertible notes.

Foreign Currency Transaction Gains or Losses

Foreign Currency Transaction Gains or Losses

Transactions denominated in foreign currencies, which are primarily contract manufacturing services, are recorded in U.S. dollars on the date of those transactions. Adjustments arising from foreign currency transactions between the purchase and the settlement dates are reflected in the consolidated statements of operations and comprehensive loss as a component of operating expenses. The Company recorded foreign currency transaction gains of $18,000 and $0.1 million in the years ended December 31, 2021 and 2020, respectively, in the consolidated statements of operations.

Concentrations of Credit Risk and of Significant Suppliers

Concentrations of Credit Risk and of Significant Suppliers

The Company has no significant off-balance sheet risk. Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents, restricted cash and investments. The Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality and has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company’s investment policy limits investment instruments to investment-grade securities with the objective to preserve capital and to maintain liquidity until the funds can be used in business operations.

The Company is dependent on third-party manufacturers to supply the drug substance and drug product for its research and development activities. These activities could be adversely affected by a significant interruption in the supply of such drug substance and drug product.

Net Loss per Share Attributable to Common Stockholders

Net Loss per Share Attributable to Common Stockholders

For the year ended December 31, 2021, the Company calculated basic net loss per share by dividing the net loss by the weighted average number of common shares outstanding during the period.

For the year ended December 31, 2020, the Company followed the two-class method for computing net loss per share, as the Company had outstanding shares during that period that met the definition of participating securities. The two-class method determines net loss per share for each class of common and participating

securities according to dividends declared or accumulated and participation rights in undistributed earnings. Basic net loss per share is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding for the period without consideration for potentially dilutive securities. Net loss attributable to common stockholders is allocated to each share on an as-converted basis as if all of the net loss for the period had been distributed. During periods in which the Company incurred a net loss, the Company does not allocate net loss to participating securities because they do not have a contractual obligation to share in the net loss of the Company.

The Company computes diluted net loss per common share after giving consideration to all potentially dilutive common equivalents, including preferred stock, common stock options and common stock issuable under the Company’s employee stock purchase plan.

Basic and diluted net loss per share attributable to common stockholders was the same for all periods presented as the inclusion of all potentially dilutive securities outstanding was anti-dilutive. Options to purchase common stock at December 31, 2021 and 2020 of 3,169,418 and 2,537,669, respectively, have been excluded from the calculation of diluted net loss per share because their inclusion would have been antidilutive.

Research and Development

Research and Development

Research and development costs are expensed in the period incurred. Research and development costs include payroll and personnel expense; consulting costs; external contract research and development costs; raw materials; drug product manufacturing costs; and allocated overhead such as depreciation and amortization, rent and utilities. Advance payments for goods and services to be used in future research and development activities are recorded as prepaid expenses and are expensed over the service period as the services are provided or when the goods are consumed.

Clinical trial costs are a component of research and development expenses. The Company accrues and expenses clinical trial activities performed by third parties based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activation, and other information provided to the Company by its vendors.

Patent Costs

Patent Costs

Costs to secure and maintain patents covering the Company’s technology and drug candidates are expensed as incurred and are classified as general and administrative expenses in the Company’s consolidated statements of operations.

Stock-Based Compensation

Stock-Based Compensation

The Company issues stock-based awards to employees and non-employees, generally in the form of stock options. The Company accounts for its stock-based compensation awards in accordance with ASC 718, Compensation—Stock Compensation. The majority of the Company’s stock-based awards have been made to employees and board of director members. The Company measures compensation cost for all equity awards at their grant-date fair value and recognize compensation expense over the requisite service period, which is generally the vesting period, on a straight-line basis. The grant date fair value of stock options is estimated using the Black-Scholes option pricing model, which requires management to make assumptions with respect to the fair value of common stock on the grant date (for those stock options granted before the Company’s initial public offering), the expected term of the award, the expected volatility of the Company’ stock, calculated based on a period of time generally commensurate with the expected term of the award, risk-free interest rates and expected dividend yields of stock. The expected term of the Company’s stock options is determined utilizing the “simplified” method for awards that qualify as “plain vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. Forfeitures are accounted for as

they occur. Historically, for periods before the Company’s initial public offering, the fair value of the shares of common stock was determined on each grant date by the board of directors based on valuation estimates from management considering the most recently available independent third-party valuation of the Company’s common stock. The Company’s board of directors also assessed and considered, with input from management, additional objective and subjective factors that it believed were relevant and which may have changed from the date of the most recent valuation through the grant date. The Company classifies stock-based compensation expense in the consolidated statements of operations in the same manner in which the award recipient’s salary and related costs are classified or in which the award recipient’s service payments are classified.

Income Taxes

Income Taxes

The Company accounts for income taxes using the asset and liability approach. Deferred tax assets and liabilities represent future tax consequences of temporary differences between the financial statement carrying amounts and the tax basis of assets and liabilities and for loss carryforwards using enacted tax rates expected to be in effect in the years in which the differences reverse. A valuation allowance is established to reduce deferred tax assets to the amounts expected to be realized. The Company also recognizes a tax benefit from uncertain tax positions only if it is “more likely than not” that the position is sustainable based on its technical merits. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. To date, the Company has not incurred interest and penalties related to uncertain tax positions. Should such costs be incurred, they would be classified as a component of provision for income taxes.

Emerging Growth Company Status

Emerging Growth Company Status

The Company is an “emerging growth company,” (EGC) as defined in the Jumpstart Our Business Startups Act, (JOBS Act), and may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not EGCs. The Company may take advantage of these exemptions until it is no longer an EGC under Section 107 of the JOBS Act and has elected to use the extended transition period for complying with new or revised accounting standards. As a result of this election, the Company’s financial statements may not be comparable to companies that comply with public company FASB standards’ effective dates. The Company may take advantage of these exemptions up until the last day of the fiscal year following the fifth anniversary of an offering or such earlier time that it is no longer an EGC.

Recently issued accounting pronouncements

Recently issued accounting pronouncements

In June 2016, the FASB issued ASU 2016-13, “Credit Losses (Topic 326).” ASU 2016-13 requires that financial assets measured at amortized cost, such as trade receivables and investments, be represented net of expected credit losses, which may be estimated based on relevant information such as historical experience, current conditions, and future expectation for each pool of similar financial asset. The new guidance requires enhanced disclosures related to trade receivables and associated credit losses. In May 2019, the FASB issued ASU No. 2019-05, “Financial Instruments—Credit Losses (Topic 326) Targeted Transition Relief,” which allows for a transition election on certain instruments. The guidance is effective for Small Reporting Companies for fiscal years beginning after December 15, 2022 and interim periods in those fiscal years. In November 2019, the FASB issued ASU No. 2019-11 which amends certain aspects of ASU No. 2016-13, including transition relief for trouble debt restructuring, among other topics. The Company is currently evaluating the impact of this pronouncement on its consolidated financial statements.

XML

Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of Fair Value Assets And Liabilities Measured On Recurring Basis

The following tables set forth the fair value of the Company’s financial assets and liabilities by level within the fair value hierarchy that are measured at fair value on a recurring basis:

	December 31, 2021
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets:
Money markets funds (included in cash equivalents)	$	49,482	$	—	$	—	$	49,482
Corporate debt securities		—		20,192		—		20,192
Total assets	$	49,482	$	20,192	$	—	$	69,674

	December 31, 2020
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets:
Money markets funds (included in cash equivalents)	$	7,839	$	—	$	—	$	7,839
Corporate debt securities		—		42,701		—		42,701
Commercial paper		—		41,103		—		41,103
Total assets	$	7,839	$	83,804	$	—	$	91,643

XML

Investments (Tables)

12 Months Ended

Dec. 31, 2021

Investments, All Other Investments [Abstract]

Summary of Amortized Cost and Estimated Fair Value Company's Available For Sale Investments

The following tables summarize the amortized cost and estimated fair value of the Company’s investments, which are considered to be available-for-sale investments as of December 31, 2021 and 2020:

As of December 31, 2021

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Short-term Investments		Investments, non-current
	(in thousands)
Corporate debt securities	$	20,206	$	—	$	(14	)	$	20,192	$	20,192	$	—

As of December 31, 2020

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Short-term Investments		Investments, non-current
	(in thousands)
Commercial paper	$	42,709	$	8	$	(16	)	$	42,701	$	42,701	$	—
Corporate debt securities		41,169		—		(66	)		41,103		10,130		30,973
Total	$	83,878	$	8	$	(82	)	$	83,804	$	52,831	$	30,973

XML

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Accrued Expenses

Accrued expenses consist of the following:

	December 31,
	2021		2020
	(in thousands)
Payroll and employee related expenses	$	2,499	$	1,555
External research and development		3,291		3,633
Other accrued expenses		204		390
Total accrued expenses	$	5,994	$	5,578

XML

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of fair value of stock option awards on the grant date using the black-scholes option valuation model

The Company estimates the fair value of stock option awards on the grant date using the Black-Scholes option valuation model with the following weighted-average assumptions:

	Year ended December 31,
	2021			2020
Risk-free interest rate		0.94	%		0.31	%
Expected term (in years)		5.90			5.92
Expected volatility		83.02	%		78.84	%
Dividend yield		—			—

Summary of activity under the company's stock option plan

The following table summarizes the activity under the Company’s stock option plan during the year ended December 31, 2021:

	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2020		2,537,669		$	9.61		8.2	$	13,177
Granted		1,484,433		$	9.28
Forfeited		(782,510	)	$	11.49
Exercised		(70,174	)	$	2.07
Outstanding at December 31, 2021		3,169,418		$	9.16		8.0	$	336
Vested and expected to vest at December 31, 2021		3,169,418		$	9.16		8.0	$	336
Exercisable at December 31, 2021		1,316,691		$	7.43		6.9	$	310

Summary of Total Stock-Based Compensation Expense

Total stock-based compensation expense was classified in the accompanying consolidated statements of operations as follows:

	Year ended December 31,
	2021		2020
	(in thousands)
Research and development	$	2,381	$	942
General and administrative		3,078		1,093
Total stock-based compensation expense	$	5,459	$	2,035

XML

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate and Effective Income Tax Rate

The following table reconciles the federal statutory income rate to the Company’s effective income tax rate:

	Year ended December 31,
	2021			2020
Tax at U.S. statutory rate		21.00	%		21.00	%
Changes from statutory rate:
State taxes, net of federal benefit		6.54	%		4.61	%
Non-deductible permanent items		(0.46	)%		—
Tax credits		6.12	%		1.97	%
Stock-based compensation		(0.51	)%		(1.11	)%
Change in valuation allowance		(32.69	)%		(26.47	)%
Effective income tax rate		0.00	%		0.00	%

Schedule of Components of Company Deferred Tax Assets

The components of the Company’s deferred tax assets are as follows:

	Year ended December 31,
	2021			2020
	(in thousands)
Deferred tax assets
Net operating loss carryforwards	$	44,919		$	30,120
Tax credits		9,239			4,891
Stock-based compensation expenses		1,032			108
Accrued expenses and other		627			612
Gross deferred tax assets		55,817			35,731
Valuation allowance		(55,806	)		(35,731	)
Total deferred tax assets, net	$	11		$	—
Deferred tax liabilities
Depreciation and amortization	$	(11	)	$	—
Total deferred tax liabilities, net	$	(11	)	$	—
Net deferred tax asset (liability)	$	—		$	—

Summary of Unrecognized Benefits

The following is reconciliation of the total amounts of unrecognized benefits:

	December 31,
	2021		2020
	(in thousands)
Unrecognized benefits at the beginning of the year	$	1,307	$	—
Additions for the tax positions related to the current year		1,126		1,307
Unrecognized benefits at the end of the year	$	2,433	$	1,307

XML

Nature of Business - Additional Information (Detail) $ / shares in Units, $ in Thousands				12 Months Ended
	Sep. 03, 2020 shares	Aug. 11, 2020 USD ($) $ / shares shares	Jul. 31, 2020	Dec. 31, 2021 shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 shares
Subsidiary, Sale of Stock [Line Items]
Proceeds from initial public offering of common stock, net of underwriting discounts, commissions and issuance costs | $		$ 67,700			$ 82,539
Temporary Equity, Shares Outstanding				0	0	51,283,386
Common Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Shares Issued During Period					5,109,861
Reverse stock split, conversion ratio			7.4771
Description of the reverse stock split arrangement			On July 31, 2020, the Company effected a one-for-7.4771 reverse stock split of its common stock. All shares, stock options, warrants, redeemable convertible preferred stock conversion prices, ratios and per share information presented in the consolidated financial statements have been adjusted to reflect the reverse stock split on a retroactive basis for all periods presented. The par value per share and the authorized number of shares of common stock were not adjusted as a result of the reverse stock split.	On July 31, 2020, the Company effected a one-for-7.4771 reverse stock split of its common stock. All shares, stock options, warrants, redeemable convertible preferred stock conversion prices, ratios and per share information presented in the consolidated financial statements have been adjusted to reflect the reverse stock split on a retroactive basis for all periods presented. The par value per share and the authorized number of shares of common stock were not adjusted as a result of the reverse stock split.
Convertible Preferred Stock, Shares Issued upon Conversion		14,948,241
IPO [Member] | Common Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Shares Issued During Period		5,000,000
Shares Issued, Price Per Share | $ / shares		$ 15.00
Over-Allotment Option [Member] | Common Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Shares Issued During Period	109,861

XML

Going Concern - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Going Concern [Abstract]
Cash and cash equivalrents and short term investments	$ 70,900
Cash	70,900
Available for sale investments	$ 70,900	$ 83,804

XML

Summary of Significant Accounting Policies -Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash Equivalents	$ 49,500,000	$ 8,800,000
Restricted cash	20,000	20,000
Foreign currency transaction gains	$ 18,000	$ 100,000
Antidilutive securities excluded from computation of earnings per share amount	3,169,418	2,537,669
Machinery and Equipment [Member]
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 100

XML

Fair Value Measurement - Schedule of Fair Value Assets And Liabilities Measured On Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Assets, Fair Value Disclosure	$ 69,674	$ 91,643
Money markets funds (included in cash equivalents) [Member]
Assets:
Assets, Fair Value Disclosure	49,482	7,839
Commercial Paper [Member]
Assets:
Assets, Fair Value Disclosure		41,103
Corporate Debt Securities [Member]
Assets:
Assets, Fair Value Disclosure	20,192	42,701
Fair Value, Inputs, Level 1 [Member]
Assets:
Assets, Fair Value Disclosure	49,482	7,839
Fair Value, Inputs, Level 1 [Member] | Money markets funds (included in cash equivalents) [Member]
Assets:
Assets, Fair Value Disclosure	49,482	7,839
Fair Value, Inputs, Level 2 [Member]
Assets:
Assets, Fair Value Disclosure	20,192	83,804
Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member]
Assets:
Assets, Fair Value Disclosure		41,103
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member]
Assets:
Assets, Fair Value Disclosure	$ 20,192	$ 42,701

XML

Investments - Summary of Amortized Cost and Estimated Fair Value Company's Available For Sale Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		$ 83,878
Debt Securities, Available-for-sale, Unrealized Gain		8
Debt Securities, Available-for-sale, Unrealized Loss		(82)
Debt Securities, Available-for-sale, Fair Value	$ 70,900	83,804
Debt Securities, Available-for-sale, Short-term Investments		52,831
Debt Securities, Available-for-sale, Investments, non-current		30,973
Commercial Paper [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		42,709
Debt Securities, Available-for-sale, Unrealized Gain		8
Debt Securities, Available-for-sale, Unrealized Loss		(16)
Debt Securities, Available-for-sale, Fair Value		42,701
Debt Securities, Available-for-sale, Short-term Investments		42,701
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	20,206	41,169
Debt Securities, Available-for-sale, Unrealized Gain	0
Debt Securities, Available-for-sale, Unrealized Loss	(14)	(66)
Debt Securities, Available-for-sale, Fair Value	20,192	41,103
Debt Securities, Available-for-sale, Short-term Investments	20,192	10,130
Debt Securities, Available-for-sale, Investments, non-current	$ 0	$ 30,973

XML

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Payroll and employee related expenses	$ 2,499	$ 1,555
External research and development	3,291	3,633
Other accrued expenses	204	390
Total accrued expenses	$ 5,994	$ 5,578

XML

Convertible Notes - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Jun. 02, 2020	Dec. 31, 2021	Apr. 21, 2020
Convertible Notes Payable [Member]
Disclosure of Convertible Loan Notes [Line Items]
Debt Face Amount			$ 10.0
Change in fair value of convertible notes		$ 0.1
Series C Redeemable Convertible Preferred Stock [Member]
Disclosure of Convertible Loan Notes [Line Items]
Debt conversion, shares issued		6,295,756
Series C Redeemable Convertible Preferred Stock [Member] | Convertible Notes Payable [Member]
Disclosure of Convertible Loan Notes [Line Items]
Debt Instrument benenficial conversion feature	$ 10.1

XML

Redeemable Convertible Preferred Stock - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Jun. 30, 2020	Jan. 31, 2020	Dec. 31, 2020	Dec. 31, 2021	Aug. 11, 2020	Dec. 31, 2019
Temporary Equity [Line Items]
Gross Proceeds from temporary equity			$ 195,847
Temporary equity, shares outstanding			0	0		51,283,386
Temporary Equity, Shares Issued						51,283,386
Common Stock [Member]
Temporary Equity [Line Items]
Convertible Preferred Stock, Shares Issued upon Conversion					14,948,241
Series A Redeemable Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity, shares outstanding						25,000,000
Temporary Equity, Shares Issued						25,000,000
Series B Redeemable Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Net proceeds from temporary equity		$ 8,000
Temporary equity, shares outstanding						26,283,386
Temporary equity shares issued during the period		3,688,898
Temporary Equity, Shares Issued						26,283,386
Series C Redeemable Convertible Preferred Stock [Member] | Series C Preferred Stock Purchase Agreement [Member]
Temporary Equity [Line Items]
Gross Proceeds from temporary equity	$ 74,600
Temporary equity shares issued during the period	46,828,167
Series C Redeemable Convertible Preferred Stock [Member] | Series C Preferred Stock Purchase Agreement [Member] | Convertible Notes Payable [Member] | Unsecured Debt [Member]
Temporary Equity [Line Items]
Temporary equity shares issued during the period	6,295,756
Debt instrument converted value In excess of principal	$ 100
Debt conversion original debt amount	$ 10,000
Undesignated Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity shares authorised				10,000,000
Temporary Equity, Shares Issued				0

XML

Stock based compensation - Schedule of fair value of stock option awards on the grant date using the Black-Scholes option valuation model (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk-free interest rate	0.94%	0.31%
Expected term (in years)	5 years 10 months 24 days	5 years 11 months 1 day
Expected volatility	83.02%	78.84%
Dividend yield	0.00%	0.00%

XML

Stock based compensation - Summary the activity under the Company's stock option plan (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Outstanding Number, Beginning balance	2,537,669
Outstanding Number, Granted	1,484,433
Outstanding Number, Forfeited	(782,510)
Outstanding Number ,Exercised	(70,174)
Outstanding Number , Ending balance	3,169,418	2,537,669
Outstanding Number, Vested and expected to vest	3,169,418
Outstanding Number, Exercisable	1,316,691
Weighted Average Exercise price, Beginning balance	$ 9.61
Weighted Average Exercise price, Granted	9.28
Weighted Average Exercise price, Forfeited	11.49
Weighted Average Exercise price, Exercised	2.07
Weighted Average Exercise price, Ending balance	9.16	$ 9.61
Weighted Average Exercise price, Vested and expected to vest	9.16
Weighted Average Exercise price, Exercisable	$ 7.43
Weighted-Average Remaining Contractual Term	8 years	8 years 2 months 12 days
Weighted-Average Remaining Contractual Term, Vested and expected to vest	8 years
Weighted-Average Remaining Contractual Term, Exercisable	6 years 10 months 24 days
Aggregate Intrinsic Value	$ 336	$ 13,177
Aggregate Intrinsic Value, Vested and expected to vest	336	$ 13,177
Aggregate Intrinsic Value, Exercisable	$ 310

XML

Stock-Based Compensation - Summary of Total Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,459	$ 2,035
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	2,381	942
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,078	$ 1,093

XML

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Jan. 01, 2021	Jul. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Aug. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised			70,174
2015 Stock Option and Grant Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Award, Number of Shares Available for Issuance					729,575
Unrecognized compensation expense related to stock option			$ 11.4
Unrecognized compensation expense expected to be recognized, Weighted average period			2 years 6 months
Options exercised			800,000
Weighted average grant date fair value of stock options granted, fair value			$ 6.46	$ 14.50
2020 Stock Option and Grant Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Award, Number of Shares Available for Issuance				2,617,066	3,205,430
Discount on purchase		85.00%
Shares of common stock reserved for issuance under 2015 plan		267,119
Share-based Payment Award, Percentage of Outstanding Stock Maximum	4.00%
2020 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance under 2015 plan				267,119
Share-based Payment Award, Percentage of Outstanding Stock Maximum		1.00%
Number of stock awards issued			0	0
Share-based payment award number of additional shares authorized			862,416
Maximum [Member] | 2020 Stock Option and Grant Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount on purchase		15.00%
Share-based Payment Award, Number of Shares Authorized for Issuance			4,797,421

XML

Income Taxes - Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate and Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Tax at U.S. statutory rate	21.00%	21.00%
Changes from statutory rate:
State taxes, net of federal benefit	6.54%	4.61%
Non-deductible permanent items	(0.46%)	0.00%
Tax credits	6.12%	1.97%
Stock-based compensation	(0.51%)	(1.11%)
Change in valuation allowance	(32.69%)	(26.47%)
Effective income tax rate	0.00%	0.00%

XML

Income Taxes - Schedule of Components of Company Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets
Net operating loss carryforwards	$ 44,919	$ 30,120
Tax credits	9,239	4,891
Stock-based compensation expenses	1,032	108
Accrued expenses and other	627	612
Gross deferred tax assets	55,817	35,731
Valuation allowance	(55,806)	(35,731)
Total Deferred tax assets, net	11	0
Deferred tax liabilities
Depreciation and amortization	(11)	0
Total deferred tax liabilities, net	(11)	0
Net deferred tax asset (liability)	$ 0	$ 0

XML

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Line Items]
Valuation allowance	$ 55,806	$ 35,731
Increase in valuation allowance	20,100	9,800
Operating loss carryforwards	1,300
Research and development tax credit carryforward, amount	$ 12,200
Operating loss carry forward limitation description	Net operating loss and research and development tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions.
Unrecognized tax benefits	$ 2,433	1,307	$ 0
Uncetain tax positions related to accrued interest and penalities	$ 0	$ 0
Description Income tax examinations	The federal and state income tax returns are generally subject to examinations for the tax years ended December 31, 2018 through December 31, 2021.
Domestic Tax Authority [Member]
Income Tax Disclosure [Line Items]
Operating loss carryforwards	$ 169,300
Operating loss carryforwards indefinite carryforward period	138,000
Operating loss carryforwards subject to expiration	$ 31,300
Operating loss carryforwards expiration year	2037
State and Local Jurisdiction [Member]
Income Tax Disclosure [Line Items]
Operating loss carryforwards	$ 147,900
Maximum [Member] | State and Local Jurisdiction [Member]
Income Tax Disclosure [Line Items]
Operating loss carryforwards expiration year	2041

XML

Income Taxes - Summary of Unrecognized Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Uncertainties [Abstract]
Unrecognized benefits at the beginning of the year	$ 1,307	$ 0
Additions for the tax positions related to the current year	1,126	1,307
Unrecognized benefits at the end of the year	$ 2,433	$ 1,307

XML

Commitments And Contingencies - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Long-term Purchase Commitment [Line Items]
Research and development expenses recognised				$ 45,819	$ 26,719
Operating lease rental expenses				$ 600	$ 500
No of days that agreement to be terminated by both parties				60 days
No of days that agreement to be Voluntary terminated by company				90 days
Kuros License Agreement [Member]
Long-term Purchase Commitment [Line Items]
Long-term Agreement commitment amount	$ 56,000
Milestone Payments				$ 8,300
Percentage of royalities on licensed knowhow				50.00%
Kuros License Agreement [Member] | Research And Development Expense Two Thousand Sixteen [Member] | Phase Two Trial [member]
Long-term Purchase Commitment [Line Items]
Research and development expenses recognised			$ 4,000
Kuros License Agreement [Member] | Research And Development Expense Two Thousand Twenty One [Member] | Phase Two Trial [member]
Long-term Purchase Commitment [Line Items]
Research and development expenses recognised				$ 2,000
Master Clinical Trial Collaboration Agreement [Member]
Long-term Purchase Commitment [Line Items]
Long-term Agreement commitment amount		$ 0
CMPI Kuros License Agreement [Member]
Long-term Purchase Commitment [Line Items]
License agreement license fees and milestone costs Incurred				$ 6,000

XML

Defined Contribution Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Retirement Benefits [Abstract]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 0.2	$ 0.1