10-Q

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q

(Mark One)

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

For the quarterly period ended September 30, 2022

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: 001-38586

RUBIUS THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Delaware	46-2688109
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
399 Binney Street, Suite 300 Cambridge, Massachusetts (Address of principal executive offices)	02139 (Zip code)

(617) 679-9600

(Registrant’s telephone number, including area code)

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 $0.001 per share	RUBY	The Nasdaq Global Select Market

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, if any, every Interactive Data File required to be submitted 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 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	☐

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

As of October 31, 2022, the registrant had 90,371,532 shares of common stock, $0.001 par value per share, outstanding.

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FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains express or implied forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, that are based on our management’s belief and assumptions and on information currently available to our management. These statements reflect our current views with respect to, among other things, our operations and financial performance. All statements other than statements of historical facts contained in this Quarterly Report on Form 10-Q, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plan, objectives of management, results of preclinical studies or clinical trials and expected market growth are forward-looking statements. You can identify these forward-looking statements by the use of words such as “outlook,” “believes,” “expects,” “potential,” “continues,” “may,” “will,” “should,” “seeks,” “approximately,” “predicts,” “intends,” “plans,” “estimates,” “anticipates” or the negative version of these words or other comparable words. Such forward-looking statements involve various risks and uncertainties that could cause actual outcomes or results to differ materially from those indicated in these statements. Forward-looking statements in this Quarterly Report on Form 10-Q include, but are not limited to, statements about:

•our recently announced plan to review strategic alternatives and significantly and immediately reduce our operations;

•our ability to fund our planned operations for the next twelve months and our ability to continue to operate as a going concern;

•expectations that our cash will be sufficient to fund our operating expenses and capital expenditure requirements into the first quarter of 2023, particularly in light of our recent payoff with SLR;

•expectations that we will be able to obtain funding for our operations, including funding necessary to complete further development, any future clinical trials we may conduct and, if approved, commercialization of any product candidates we may develop;

•beliefs about developments relating to cellular therapies, including red blood cell therapies;

•beliefs regarding and plans for our identified research priorities to advance our technologies;

•our plans to research, develop and commercialize any future product candidates;

•estimates for expenses, future revenue, capital requirements and needs for, and ability to obtain, additional financing;

•expectations regarding the success, cost and timing of our product development activities and any future clinical trials we may conduct, including statements regarding the timing of initiation, enrollment in and completion of any such trials and related preparatory work, the period during which the results of such trials will become available, and our research and development programs;

•plans to advance product candidates into or successfully complete any clinical trial;

•beliefs about data results and analyses, including what early data demonstrates or suggests, as well as expectations regarding the safety and efficacy, and overall potential and advantages, of any product candidates we may develop and our expected timing for data;

•beliefs that we can obtain or manufacture adequate and timely supply of any product candidates we may develop for future clinical trials or for commercial use, if approved;

•expectations regarding the potential sale of our manufacturing facility;

•our expectations regarding our ability to obtain and maintain intellectual property protection for any product candidates we may develop;

•plans to license additional intellectual property relating to any product candidates we may develop and expectations that we will be able to comply with our existing license agreements;

•beliefs about the intellectual property rights of others and our ability to commercialize any product candidates we may develop in light of such third-party rights;

•expectations for competing therapies that are or become available;

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•plans for the commercialization of, and expectations for the market for, any product candidates we may develop, if approved;

•our plans to attract collaborators with development, regulatory and commercialization expertise;

•expectations to enter into agreements with third parties in connection with the commercialization of any product candidates we may develop, if approved;

•beliefs about the size and growth potential of the markets for any product candidates we may develop, and our ability to serve those markets;

•expectations for the impact of global economic and political developments on our business and on any future clinical trials we may conduct, including economic slowdowns or recessions that may result from the ongoing COVID-19 pandemic;

•expectations for the rate and degree of market acceptance of any product candidates we may develop, if approved;

•anticipated regulatory developments in the United States and foreign countries;

•expectations that we will be able to contract with third-party suppliers and manufacturers and their ability to perform adequately; and

•the expected impact of laws and regulations and legislative and regulatory changes.

All of our forward-looking statements are as of the date of this Quarterly Report on Form 10-Q only. In each case, actual results may differ materially from such forward-looking information. We can give no assurance that such expectations or forward-looking statements will prove to be correct. An occurrence of or any material adverse change in one or more of the risk factors or risks and uncertainties referred to in this Quarterly Report on Form 10-Q or included in our other public disclosures or our other periodic reports or other documents or filings filed with or furnished to the Securities and Exchange Commission, or the SEC, could materially and adversely affect our business, prospects, financial condition and results of operations. Except as required by law, we do not undertake or plan to update or revise any such forward-looking statements to reflect actual results, changes in plans, assumptions, estimates or projections or other circumstances affecting such forward-looking statements occurring after the date of this Quarterly Report on Form 10-Q, even if such results, changes or circumstances make it clear that any forward-looking information will not be realized. Any public statements or disclosures by us following this Quarterly Report on Form 10-Q that modify or impact any of the forward-looking statements contained in this Quarterly Report on Form 10-Q will be deemed to modify or supersede such statements in this Quarterly Report on Form 10-Q.

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Summary of the Material Risks Associated with Our Business

Our business is subject to numerous risks and uncertainties that you should be aware of in evaluating our business. These risks include, but are not limited to, the following:

•we do not currently have sufficient working capital to fund our planned operations for the next 12 months and may not be able to continue as a going concern, and our cash has been significantly depleted by our recent payoff of the SLR loan. Further, we have recently announced a strategic plan, which significantly reduced our operations to focus on our pursuit of strategic alternatives;

•we have significantly reduced our employee base;

•we will require additional capital to fund our operations and if we fail to obtain necessary financing (which will be challenging if not impossible to obtain), we will not be able to complete the development and commercialization of our product candidates;

•we have incurred net losses in every year since our inception and anticipate that we will continue to incur net losses in the future;

•we have a limited operating history, which may make it difficult to evaluate our technology and product development capabilities and predict our future performance;

•our business is highly dependent on the success of our preclinical programs targeting cancer and autoimmune diseases. Any of our product candidates that we may develop will require significant additional nonclinical, preclinical and clinical development before we can seek regulatory approval for and launch a product commercially;

•the successful development of cellular therapeutics, such as our Red Cell Therapeutics, or RCTs, is highly uncertain;

•our future product candidates are based on a new technology, which makes it difficult to predict the time and cost of development and of subsequently obtaining regulatory approval, if at all;

•the FDA, the EMA and other regulatory authorities may implement additional regulations or restrictions on the development and commercialization of our product candidates, which may be difficult to predict;

•clinical development involves a lengthy and expensive process, with an uncertain outcome. We may incur additional costs or experience delays in completing, or ultimately be unable to complete, the development and commercialization of any product candidates;

•the clinical trials we conduct or those of our future collaborators may reveal significant adverse events not seen in our preclinical or nonclinical studies and may result in a safety profile that could inhibit regulatory approval or market acceptance of any of our product candidates;

•positive results from early preclinical studies or early clinical trials are not necessarily predictive of the results of later preclinical studies or later clinical trials;

•if we encounter difficulties enrolling patients in any clinical trials we may conduct in the future, our clinical development activities could be delayed or otherwise adversely affected;

•cellular therapies are a novel approach and negative perception of any product candidates that we may develop could adversely affect our ability to conduct our business or obtain regulatory approvals for such product candidates;

•we are subject to numerous laws and regulations, noncompliance with which would subject us to possible legal or regulatory action;

•the effects of health epidemics like the ongoing COVID-19 pandemic, including recurring surges and waves of infection and emergent variants of the coronavirus, in regions where we, or the third parties on which we rely, have business operations has affected, and may continue to affect, our business, including our preclinical studies and research and development efforts;

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•if we are unable to obtain and maintain patent protection for any product candidates we develop or for our next generation red blood cell platform, our competitors could develop and commercialize products or technology similar or identical to ours, and our ability to successfully commercialize any product candidates we may develop, and our technology may be adversely affected;

•we intend to rely on patent and other rights and available regulatory exclusivities, including the status of our future product candidates, if approved, as products eligible for reference product exclusivity under the Biologics Price Competition and Innovation Act, or BPCIA. If we are unable to obtain or maintain exclusivity from the combination of these approaches, we may not be able to compete effectively in our markets;

•third-party claims of intellectual property infringement, misappropriation or other violation against us, our licensors or our collaborators may prevent or delay the development and commercialization of our product candidates, our next generation red blood cell platform and other technologies;

•the manufacturing process we have been developing is unique. If we or any third-party manufacturers that we may engage encounter difficulties in manufacturing our future product candidates or any of their components, our ability to provide supply of our such product candidates for clinical trials or our products for patients, if approved, could be delayed or stopped, or we may be unable to maintain a commercially viable cost structure; and

•if we fail to maintain the listing of our common stock with a United States national securities exchange, the liquidity of our common stock could be adversely affected.

The summary risk factors described above should be read together with the text of the full risk factors below and in the other information set forth in this Quarterly Report on Form 10-Q, including our condensed consolidated financial statements and the related notes, as well as in other documents that we file with the SEC. If any such risks and uncertainties actually occur, our business, prospects, financial condition and results of operations could be materially and adversely affected. The risks summarized above or described in full below are not the only risks that we face. Additional risks and uncertainties not currently known to us, or that we currently deem to be immaterial may also materially adversely affect our business, prospects, financial condition and results of operations.

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Rubius Therapeutics, Inc.

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		Page No.
PART I - FINANCIAL INFORMATION
Item 1.	Condensed Consolidated Financial Statements	1
	Condensed Consolidated Balance Sheets (Unaudited)	1
	Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)	2
	Condensed Consolidated Statements of Cash Flows (Unaudited)	3
	Condensed Consolidated Statements of Stockholders’ Equity (Unaudited)	4
	Notes to Condensed Consolidated Financial Statements (Unaudited)	6
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	17
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	31
Item 4.	Controls and Procedures	31
PART II - OTHER INFORMATION
Item 1.	Legal Proceedings	33
Item 1A.	Risk Factors	33
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	89
Item 3.	Defaults Upon Senior Securities	89
Item 4.	Mine Safety Disclosures	89
Item 5.	Other Information	89
Item 6.	Exhibits	90
Signatures		92

Solely for convenience, the trademarks, service marks and trade names referred to in this quarterly report are listed without the ®, (sm) and ™ symbols, but we will assert, to the fullest extent under applicable law, our rights or the rights of the applicable licensors to these trademarks, service marks and trade names.

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PART I—FINANCIAL INFORMATION

Item 1. Condensed Consolidated Financial Statements (Unaudited)

RUBIUS THERAPEUTICS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share amounts)

(Unaudited)

	September 30, 2022		December 31, 2021
Assets
Current assets:
Cash and cash equivalents	$	103,884	$	225,848
Assets held for sale	4,257		—
Prepaid expenses and other current assets	2,682		3,975
Total current assets	110,823		229,823
Operating lease, right-of-use asset	31,207		35,095
Property, plant and equipment, net	27,094		51,530
Restricted cash	1,573		1,573
Total assets	$	170,697	$	318,021
Liabilities and Stockholders' Equity
Current liabilities:
Accounts payable	$	8,717	$	11,572
Accrued expenses and other current liabilities	14,695		14,072
Operating lease liabilities	9,212		9,015
Total current liabilities	32,624		34,659
Long-term debt, net of discount	76,829		76,154
Other long-term liabilities	—		135
Operating lease liabilities, net of current portion	24,657		28,291
Total liabilities	134,110		139,239
Commitments and contingencies (see Note 9)
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized at September 30, 2022 and December 31, 2021; no shares issued or outstanding at September 30, 2022 and December 31, 2021	—		—
Common stock, $0.001 par value; 300,000,000 and 150,000,000 shares authorized at September 30, 2022 and December 31, 2021, respectively; 90,370,532 and 90,063,770 shares issued and outstanding at September 30, 2022 and December 31, 2021, respectively	90		90
Additional paid-in capital	873,041		855,710
Accumulated deficit	(836,544)		(677,018)
Total stockholders' equity	36,587		178,782
Total liabilities and stockholders' equity	$	170,697	$	318,021

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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RUBIUS THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except share and per share amounts)

(Unaudited)

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Revenue	$	—	$	—	$	—	$	—
Operating expenses:
Research and development	24,229		38,014		95,526		101,763
General and administrative	7,301		12,035		29,772		39,126
Restructuring and impairment charges	30,052		—		30,052		—
Total operating expenses	61,582		50,049		155,350		140,889
Loss from operations	(61,582)		(50,049)		(155,350)		(140,889)
Other income (expense):
Interest income	392		23		695		75
Interest expense	(1,736)		(1,711)		(4,995)		(4,771)
Other income, net	53		2,721		124		4,059
Total other income (expense), net	(1,291)		1,033		(4,176)		(637)
Net loss	$	(62,873)	$	(49,016)	$	(159,526)	$	(141,526)
Net loss per share, basic and diluted	$	(0.70)	$	(0.55)	$	(1.77)	$	(1.62)
Weighted average common shares outstanding, basic and diluted	90,364,222		89,807,383		90,262,487		87,240,694
Comprehensive loss:
Net loss	$	(62,873)	$	(49,016)	$	(159,526)	$	(141,526)
Other comprehensive income (loss):
Unrealized gains (losses) on investments, net of tax of $0	122		(1)		—		(4)
Comprehensive loss	$	(62,751)	$	(49,017)	$	(159,526)	$	(141,530)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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RUBIUS THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

(Unaudited)

	Nine Months Ended September 30,
	2022		2021
Cash flows from operating activities:
Net loss	$	(159,526)	$	(141,526)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	17,099		26,428
Depreciation and amortization expense	5,827		4,331
Amortization (accretion) of premium (discount) on investments	(305)		118
Non-cash interest expense	621		1,036
Impairment charges	17,787		—
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	1,131		(1,226)
Operating lease, right-of-use-asset	3,888		4,156
Accounts payable	(2,551)		2,773
Accrued expenses and other current liabilities	1,976		(416)
Other long-term liabilities	(135)		(102)
Operating lease liabilities	(3,437)		(3,477)
Net cash used in operating activities	(117,625)		(107,905)
Cash flows from investing activities:
Purchases of property, plant and equipment	(5,038)		(2,280)
Purchases of investments	(78,445)		—
Sales and maturities of investments	78,750		85,000
Net cash provided by (used in) investing activities	(4,733)		82,720
Cash flows from financing activities:
Proceeds from underwritten public offering of common stock, net of commissions and underwriting discounts	—		188,000
Payments of offering costs	—		(360)
Payments of debt issuance costs	—		(150)
Proceeds from issuance of common stock upon exercise of stock options and under employee stock purchase plan	232		10,547
Net cash provided by financing activities	232		198,037
Net increase (decrease) in cash, cash equivalents and restricted cash	(122,126)		172,852
Cash, cash equivalents and restricted cash at beginning of period	227,583		92,901
Cash, cash equivalents and restricted cash at end of period	$	105,457	$	265,753
Supplemental cash flow information:
Cash paid for interest	$	4,374	$	3,635
Cash paid for leases	$	5,386	$	5,675
Supplemental disclosure of non-cash investing and financing information:
Purchases of property, plant and equipment included in accounts payable or accrued expenses	$	333	$	1,145
Offering costs included in accounts payable and accrued expenses	$	—	$	35

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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RUBIUS THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(In thousands, except share amounts)

(Unaudited)

						Accumulated
				Additional		other				Total
	Common stock			paid-in		comprehensive		Accumulated		stockholders’
	Shares	Amount		capital		loss		deficit		equity
Balances at December 31, 2021	90,063,770	$	90	$	855,710	$	—	$	(677,018)	$	178,782
Issuance of common stock upon exercise of stock options	18,228	—		76		—		—		76
Vesting of restricted stock units	104,628	—		—		—		—		—
Stock-based compensation expense	—	—		8,260		—		—		8,260
Unrealized losses on investments	—	—		—		(57)		—		(57)
Net loss	—	—		—		—		(52,412)		(52,412)
Balances at March 31, 2022	90,186,626	$	90	$	864,046	$	(57)	$	(729,430)	$	134,649
Issuance of common stock upon exercise of stock options	24,000	—		22		—		—		22
Vesting of restricted stock units	2,500	—		—		—		—		—
Issuance of common stock under    employee stock purchase plan	143,906	—		134		—		—		134
Stock-based compensation expense	—	—		5,041		—		—		5,041
Unrealized losses on investments	—	—		—		(65)		—		(65)
Net loss	—	—		—		—		(44,241)		(44,241)
Balances at June 30, 2022	90,357,032	$	90	$	869,243	$	(122)	$	(773,671)	$	95,540
Vesting of restricted stock units	13,500	—		—		—		—		—
Stock-based compensation expense	—	—		3,798		—		—		3,798
Unrealized gains on investments	—	—		—		122		—		122
Net loss	—	—		—		—		(62,873)		(62,873)
Balances at September 30, 2022	90,370,532	$	90	$	873,041	$	—	$	(836,544)	36,587

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RUBIUS THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(In thousands, except share amounts)

(Unaudited)

						Accumulated
				Additional		other				Total
	Common stock			paid-in		comprehensive		Accumulated		stockholders’
	Shares	Amount		capital		income		deficit		equity
Balances at December 31, 2020	81,053,651	$	81	$	621,946	$	4	$	(480,471)	$	141,560
Issuance of common stock    from public offering, net of    commissions, underwriting    discounts and offering costs of    $800	6,896,552	7		187,193		—		—		187,200
Issuance of common stock upon exercise of stock options	1,237,324	1		5,907		—		—		5,908
Stock-based compensation expense	—	—		8,642		—		—		8,642
Unrealized gains on investments	—	—		—		3		—		3
Net loss	—	—		—		—		(42,330)		(42,330)
Balances at March 31, 2021	89,187,527	$	89	$	823,688	$	7	$	(522,801)	$	300,983
Issuance of common stock upon exercise of stock options	532,400	1		3,719		—		—		3,720
Stock-based compensation expense	—	—		9,597		—		—		9,597
Unrealized losses on investments	—	—		—		(6)		—		(6)
Net loss	—	—		—		—		(50,180)		(50,180)
Balances at June 30, 2021	89,719,927	$	90	$	837,004	$	1	$	(572,981)	$	264,114
Issuance of common stock upon exercise of stock options	142,555	—		919		—		—		919
Stock-based compensation expense	—	—		8,189		—		—		8,189
Unrealized losses on investments	—	—		—		(1)		—		(1)
Net loss	—	—		—		—		(49,016)		(49,016)
Balances at September 30, 2021	89,862,482	$	90	$	846,112	$	—	$	(621,997)	$	224,205

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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RUBIUS THERAPEUTICS, INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

1. Nature of the Business and Basis of Presentation

Rubius Therapeutics, Inc. (“Rubius” or the “Company”) is a biopharmaceutical company that is using chemical conjugation to turn red blood cells into medicines, called Red Cell Therapeutics, for the treatment of cancer and autoimmune diseases. Rubius was incorporated in April 2013 as VL26, Inc. under the laws of the State of Delaware. In January 2015, the Company changed its name to Rubius Therapeutics, Inc.

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations, the ability to establish clinical- and commercial-scale manufacturing processes and the ability to secure additional capital to fund operations. In addition, the Company is subject to uncertainty regarding the performance and safety of its product candidates in humans. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s drug development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

The Company is monitoring the potential impact of the novel coronavirus (“COVID-19”), if any, on the carrying value of certain assets. To date, the Company has not experienced material business disruption, nor has it incurred impairment of any assets as a result of COVID-19. The extent to which these events may impact the Company’s business will depend on future developments, which are highly uncertain and cannot be predicted at this time. The duration and intensity of these impacts and resulting disruption to the Company’s operations is uncertain and the Company will continue to assess the financial impact.

On July 20, 2018, the Company completed its initial public offering (“IPO”), pursuant to which it issued and sold 12,055,450 shares of common stock, inclusive of 1,572,450 shares sold by the Company pursuant to the full exercise of the underwriters’ option to purchase additional shares. The aggregate net proceeds received by the Company from the IPO were $254.3 million, after deducting underwriting discounts and commissions and other offering costs. Upon the closing of the IPO, all of the shares of the Company’s outstanding convertible preferred stock then outstanding automatically converted into 51,845,438 shares of common stock.

On March 18, 2021, the Company completed an underwritten public offering (the “March 2021 Offering”), pursuant to which it issued and sold 6,896,552 shares of common stock. The aggregate net proceeds received by the Company from the March 2021 Offering were $187.2 million, after deducting underwriting discounts and commissions and other offering costs.

In September 2022, the Company's Board of Directors approved certain operational and organizational steps that the Company will undertake in connection with a new strategic reorganization plan and related cost-saving measures (collectively, the “Reorganization Plan”). The Company discontinued its ongoing Phase 1 clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors and restructured the organization to support advancing drug candidates based on its next generation platform. Under the Reorganization Plan, the Company also reduced its overall workforce by approximately 75%, primarily consisting of employees who were focused on clinical development of RTX-240 and RTX-224, with the remainder coming from its manufacturing and general and administrative functions. Additionally, the Company is exploring the sale of its manufacturing facility in Smithfield, Rhode Island.

The Company’s cash and cash equivalents as of September 30, 2022 is $103.9 million. In October 2022, the Company used $75.7 million of its cash and cash equivalents to extinguish its long-term debt and satisfy its obligations under the loan and security agreement with SLR Investment Corp (Note 6).

On November 2, 2022, the Company announced that, in light of the Company’s financial condition, including the repayment and termination of its $75.0 million credit facility with SLR Investment Corp., and the early stage of its programs, its Board of Directors approved a plan to review strategic alternatives, including a sale or merger of the Company or one or more sales of its assets, and to significantly and immediately reduce its operations (the “Strategic Plan”). In connection with the Strategic Plan, the Company has terminated 42 of its employees (representing 82% of its current employee base), leaving a core team of individuals to lead the strategic review process.

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As a result of the Strategic Plan, the Company’s current financial resources and currently forecasted operating plan would allow the Company to operate into the first quarter of 2023. The Company expects its Strategic Plan will reduce its operating expenses with the goal of allowing the Company to pursue any viable strategic alternatives. There is no guarantee that this plan will be successful. The Company may not be able to successfully pursue any strategic alternatives and, even if certain strategic alternatives may be available, the Company cannot provide any assurance that the strategic alternatives review process will result in any particular alternative, transaction or value.

Under Accounting Standards Update (“ASU”) 2014-15, Presentation of Financial Statements—Going Concern (Subtopic 205-40) (“ASC 205-40”), the Company has the responsibility to evaluate whether conditions and/or events raise substantial doubt about its ability to meet its future financial obligations as they become due within one year after the date that the financial statements are issued.

As of September 30, 2022, the Company had an accumulated deficit of $836.5 million, and cash and cash equivalents of $103.9 million. For the nine months ended September 30, 2022, the Company incurred a loss of $159.5 million and used $117.6 million of cash in operations. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future. Management has assessed the Company’s ability to continue as a going concern in accordance with the requirements of ASC 205-40 and based on its recurring losses from operations incurred since inception, expectation of continuing operating losses for the foreseeable future, and the need to raise additional capital to finance its future operations, as of November 9, 2022, the issuance date of the interim condensed consolidated financial statements for the three and nine month periods ended September 30, 2022, the Company has concluded that there is substantial doubt about its ability to continue as a going concern for a period of one year from the date that these interim condensed consolidated financial statements are issued. The accompanying condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Accordingly, the condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

The Company’s condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”).

The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation.

2. Summary of Significant Accounting Policies

Unaudited Interim Financial Information

The condensed consolidated balance sheet at December 31, 2021 was derived from audited financial statements but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of September 30, 2022 and for the three and nine months ended September 30, 2022 and 2021 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K for the year-ended December 31, 2021, on file with the SEC. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position as of September 30, 2022 and condensed consolidated results of operations for the three and nine months ended September 30, 2022 and 2021 and the condensed consolidated cash flows for the nine months ended September 30, 2022 and 2021 have been made. The Company’s condensed consolidated results of operations for the three and nine months ended September 30, 2022 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2022.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the accrual of research and development expenses, the valuation of stock-based awards and the valuation of long-lived assets. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that

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it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts and experience. Actual results may differ from those estimates or assumptions.

The full extent to which the ongoing COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, including clinical trials, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19. As of the date of issuance of these unaudited condensed consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update estimates, judgments or revise the carrying value of any assets or liabilities. Actual results may differ from those estimates or assumptions.

Concentrations of Credit Risk and of Significant Suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company’s cash and cash equivalents, as of September 30, 2022, consisted of cash and money market accounts. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and raw materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services or the availability of raw materials.

Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents.

Restricted Cash

As of September 30, 2022 and December 31, 2021, the Company maintained letters of credit for the benefit of the landlords of its leased properties totaling $1.6 million and $1.7 million, respectively. The Company was required to maintain separate cash balances of these amounts to secure the letters of credit. Related to these separate cash balances, the Company included $1.6 million in restricted cash (non-current) in its condensed consolidated balance sheet as of September 30, 2022. As of December 31, 2021, the Company included $0.1 million in prepaid expenses and other current assets and $1.6 million in restricted cash (non-current) in its condensed consolidated balance sheet.

Cash, cash equivalents and restricted cash presented in the accompanying condensed consolidated statement of cash flows was $105.5 million and $265.8 million for the nine months ended September 30, 2022 and 2021, respectively, of which $1.6 million and $1.7 million was restricted cash, respectively.

Fair Value Measurements

Certain assets and liabilities are carried at fair value under 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 and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

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The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. The carrying value of the Company’s long-term debt approximates its fair value due to its variable interest rate, which approximates a market interest rate.

Investments

The Company’s investments are classified as available-for-sale and are carried at fair value. Realized gains and losses and declines in value are based on the specific identification method and are included as a component of other income (expense), net in the condensed consolidated statements of operations and comprehensive loss. The Company classifies its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such investments are available for current operations.

The Company evaluates its investments with unrealized losses for impairment. When assessing investments for unrealized declines in value, the Company considers whether the decline in value is related to a credit loss or non-credit loss. For credit losses, the Company reduces the investment to fair value through an allowance for credit losses recorded to the balance sheet and corresponding charge to the statement of operations. The allowance for credit losses and corresponding impairment charge is adjusted each period for changes in fair value. For non-credit losses, the Company reduces the investment to fair value through a charge to the statement of comprehensive loss, reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. No such credit losses were recorded during the periods presented.

Assets Held for Sale

The Company classifies its long-lived assets to be sold as held for sale in the period (i) the Company has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures a long-lived asset that is classified as held for sale at the lower of its carrying value or fair value, less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a long-lived asset until the date of sale. Upon designation as an asset held for sale, the Company stops recording depreciation and amortization expense on long-lived assets. The Company assesses the fair value of a long-lived asset, less any costs to sell, at each reporting period and until the asset is no longer classified as held for sale.

Leases

At the inception of an arrangement as lessee or lessor, the Company determines whether the arrangement is or contains a lease. Operating lease cost is recognized over the lease term on a straight-line basis. Variable lease cost and short-term leases (lease terms less than 12 months) are recognized as incurred. For both lessee and lessor arrangements, variable lease payments are the amounts owed by the Company to a lessor that are not fixed, such as reimbursement for common area maintenance and utilities costs, and are expensed when incurred. When determining the lease term, the Company includes options to extend or terminate the lease when it is reasonably certain that it will exercise that option.

For lessee arrangements, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes its incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. Operating leases are recognized on the balance sheet as right-of-use assets, operating lease liabilities current and operating lease liabilities non-current.

The Company has elected the following lease policies at the inception of a lease: (1) for lessee and lessor arrangements within all asset classes, combine lease and non-lease components as a single component, with the lease expense recognized over the expected term on a straight-line basis and (2) for lessee arrangements, apply short-term lease exemption for all leases that qualify, where a right-of-use asset or lease liability will not be recognized for leases with terms of one year or less.

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Impairment of Long-Lived Assets

Long-lived assets consist of property, plant and equipment and operating lease, right-of-use asset. 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 underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of 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 and eventual disposition 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.

3. Investments and Fair Value of Financial Assets and Liabilities

The Company had no investments as of September 30, 2022 or December 31, 2021.

The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):

	September 30, 2022
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. government money market funds	$	96,729	$	—	$	—	$	96,729
	$	96,729	$	—	$	—	$	96,729

	December 31, 2021
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S government money market funds	$	217,009	$	—	$	—	$	217,009
	$	217,009	$	—	$	—	$	217,009

U.S. government money market funds were valued by the Company based on quoted market prices, which represent a Level 1 measurement within the fair value hierarchy. There were no changes to the valuation methods used during the nine months ended September 30, 2022. The Company evaluates transfers between levels at the end of each reporting period. There were no transfers between Level 1, Level 2 or Level 3 during the nine months ended September 30, 2022.

4. Property, Plant and Equipment, Net and Assets Held for Sale

Property, plant and equipment, net and assets held for sale consisted of the following, after the effects of impairment charges and held-for-sale reclassifications (in thousands):

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	September 30, 2022		December 31, 2021
Land	$	1,300	$	1,300
Manufacturing facility	25,469		33,203
Manufacturing equipment	7,329		8,831
Laboratory equipment	1,333		17,501
Computer equipment	2,160		2,645
Furniture and fixtures	17		1,281
Leasehold improvements	570		444
Construction-in-progress	—		4,181
	38,178		69,386
Less: Accumulated depreciation and amortization	(11,084)		(17,856)
	$	27,094	$	51,530
Assets held for sale	$	4,257	$	—

During the three and nine months ended September 30, 2022, the Company recorded impairment charges of $17.8 million due to its Reorganization Plan (Note 11).

5. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):

	September 30, 2022		December 31, 2021
Accrued employee compensation and benefits	$	2,507	$	7,451
Accrued external research and development expenses	1,185		2,713
Accrued manufacturing facility expenses	123		2,349
Accrued general and administrative expenses	780		889
Accrued employee termination benefits	4,904		—
Accrued contract termination costs	4,591		—
Other	605		670
	$	14,695	$	14,072

6. Debt

On December 21, 2018 (the “Closing Date”), the Company entered into a loan and security agreement (the "Original Loan Agreement," and, as amended, the “Loan Agreement”) with Solar Capital Ltd., now SLR Investment Corp. ("SLR"), as collateral agent for the lenders party thereto for an aggregate principal amount of $75.0 million. The aggregate principal amount was funded in three tranches of term loans of $25.0 million each. On the Closing Date, the Company made an initial borrowing of $25.0 million. In June 2019, the Company made a second borrowing of $25.0 million and in June 2020, the Company made a third and final borrowing of $25.0 million.

On June 22, 2021 (the “Amendment Closing Date”), the Company entered into an amendment (the “Amendment”) to the Original Loan Agreement. Pursuant to the Amendment, the Company and its lenders agreed to extend the interest-only period applicable to borrowings under the Loan Agreement from December 21, 2021 until July 1, 2024 and the final maturity date from December 21, 2023 until June 1, 2026. An additional tranche in the amount of $35.0 million is available at the request of the Company prior to the final maturity date, to be provided at the sole discretion of the lenders. The Amendment increases the LIBOR interest rate floor from 0.00% to 2.10%. Interest on the outstanding loan balance will accrue at a rate of 5.50%, plus the greater of 2.10% or the one-month U.S. LIBOR rate. Certain back-end fees are due to the lender at the time of final repayment based on the total funded term loans. The Company accrues the back-end fees that will be due at final repayment to outstanding debt by charges to interest expense over the term of the loans using the effective interest method. The term loans are subject to a prepayment fee of 1.00% if prepayment occurs within the first year subsequent to the Amendment Closing Date, 0.50% in the second year and 0.25% in the third year through final maturity date.

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As the terms of the Amendment were not substantially different than the terms of the Original Loan Agreement, the Amendment was accounted for as a debt modification. In conjunction with the Amendment, the Company incurred issuance costs of $0.2 million payable to the lenders, which were recorded as an additional debt discount and will be amortized to interest expense over the remaining term, together with unamortized original issuance costs as of the Amendment Closing Date, using the effective interest method.

The Loan Agreement contains financial covenants that require the Company to maintain either a minimum cash balance of $10.0 million plus accounts payable that are aged longer than ninety days or a minimum market capitalization threshold. The Company was in compliance with all such financial covenants as of September 30, 2022. The Loan Agreement contains customary representations, warranties and covenants and also includes customary events of default, including payment defaults, breaches of covenants, change of control and a material adverse change default. Upon the occurrence of an event of default, a default interest rate of an additional 4.00% per annum may be applied to the outstanding loan balances, and the lenders may declare all outstanding obligations immediately due and payable. Borrowings under the Loan Agreement are collateralized by substantially all of the Company’s assets, other than its intellectual property.

As of September 30, 2022, the estimated future principal payments due under the Loan Agreement were as follows (in thousands):

Year ending December 31,
2022 (three months ending December 31)	$	—
2023	—
2024	18,750
2025	37,500
2026 and thereafter	18,750
	$	75,000

On October 13, 2022, the Company entered into a payoff letter with SLR, under which the Company voluntarily prepaid SLR approximately $75.7 million, in full satisfaction of all obligations, including all outstanding principal, accrued interest, fees, costs, expenses and other amounts chargeable, under the Loan Agreement. The payoff letter also provided for the termination of all commitments and obligations under the Loan Agreement and release of all liens held by SLR on the Company’s assets.

7. Equity

Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are not entitled to receive dividends, unless declared by the board of directors.

On July 20, 2018, the Company filed a restated certificate of incorporation in the State of Delaware, which, among other things, restated the number of shares of all classes of stock that the Company has authority to issue to 160,000,000 shares, consisting of (i) 150,000,000 shares of common stock, $0.001 par value per share, and (ii) 10,000,000 shares of preferred stock, $0.001 par value per share. The preferred stock will have such rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences, as shall be determined by the Company’s board of directors upon issuance. The shares of preferred stock are currently undesignated.

On August 1, 2019, the Company entered into a Distribution Agreement (the “Distribution Agreement”) with J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC (the “Sales Agents”), pursuant to which the Company was able to issue and sell, from time to time, shares of its common stock having an aggregate offering price of up to $100.0 million through the Sales Agents. As of September 30, 2022, no shares of common stock were issued and sold pursuant to the Distribution Agreement, which expired in accordance with its terms on August 21, 2022, and the applicable registration statement is no longer effective.

On March 18, 2021, the Company completed the March 2021 Offering, pursuant to which it issued and sold 6,896,552 shares of common stock. The aggregate net proceeds received by the Company from the March 2021 Offering were $187.2 million, after deducting underwriting discounts and commissions and other offering costs.

On July 7, 2022, the Company filed an amendment to its Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware which increased the number of shares of common stock that the Company has

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authority to issue from 150,000,000 to 300,000,000 shares. The number of shares of preferred stock authorized for issuance was not impacted by this amendment.

8. Stock-Based Compensation

Service-Based Stock Options

During the nine months ended September 30, 2022, the Company granted options with service-based vesting conditions for the purchase of 4,104,403 shares of common stock with a weighted average exercise price of $4.37 per share and a weighted average grant-date fair value of $2.98 per share.

Stock-Based Compensation

The Company recorded stock-based compensation expense in the following expense categories of its condensed consolidated statements of operations and comprehensive loss (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development expenses	$	2,266	$	3,408	$	7,958	$	8,995
General and administrative expenses	1,532		4,781		9,141		17,433
	$	3,798	$	8,189	$	17,099	$	26,428

As of September 30, 2022, total unrecognized compensation cost related to the unvested stock-based awards was $36.2 million, which is expected to be recognized over a weighted average period of 2.3 years.

9. Commitments and Contingencies

License Agreement with the Whitehead Institute for Biomedical Research

The Company has a license agreement with the Whitehead Institute for Biomedical Research (“WIBR”), as amended, under which the Company has been granted an exclusive, sublicensable, nontransferable license under certain patent families related to the development of the Company’s red blood cell therapies (as amended, the “WIBR License”). The Company is obligated to pay WIBR annual license maintenance fees of less than $0.1 million, as well as patent-related costs, including legal fees, and low single-digit royalties based on annual net sales of licensed products and licensed services by the Company and its sublicensees. Based on the progress the Company makes in the advancement of products covered by the licensed patent rights, the Company is required to make aggregate milestone payments of up to $1.6 million upon the achievement of specified preclinical, clinical and regulatory milestones. In addition, the Company is required to pay to WIBR a percentage of the non-royalty payments that it receives from sublicensees of the patent rights licensed by WIBR. This percentage varies from low single-digit to low double-digit percentages and will be based upon the clinical stage of the product that is the subject of the sublicense. Royalties shall be paid by the Company on a licensed product-by-licensed product and country-by-country basis, beginning on the first commercial sale of such licensed product in such country until expiration of the last valid patent claim covering such licensed product in such country.

The Company has the right to terminate the WIBR License in its entirety, on a patent-by-patent or country-by-country basis, at will upon three months’ notice to WIBR. WIBR may terminate the agreement upon breach of contract or in the event of the Company’s bankruptcy, liquidation, insolvency or cessation of business related to the license.

401(k) Plan

In January 2018, the Company established 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 pre-tax basis. The Company makes matching contributions at a rate of 50% of each employee’s contribution up to a maximum employee contribution of 6% of eligible plan compensation. For the three and nine months ended September 30, 2022, the Company made matching contributions of $0.2 million and $0.8 million, respectively.

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Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, contract research organizations, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and executive officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims.

Legal Proceedings

The Company is not currently party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses as incurred the costs related to such legal proceedings.

10. Net Loss per Share

Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Numerator:
Net loss	$	(62,873)	$	(49,016)	$	(159,526)	$	(141,526)
Denominator:
Weighted average common shares outstanding, basic and diluted	90,364,222		89,807,383		90,262,487		87,240,694
Net loss per share, basic and diluted	$	(0.70)	$	(0.55)	$	(1.77)	$	(1.62)

The Company’s potential dilutive securities have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following potential common shares from the periods in the table above, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:

	September 30,
	2022	2021
Unvested restricted common stock	1,207,110	985,364
Stock options to purchase common stock	18,814,424	17,782,603
	20,021,534	18,767,967

11. Restructuring and Impairment Charges

The Company estimates that it will incur approximately $30.6 million in costs to implement the Reorganization Plan, as described in Note 1. The actions associated with the Reorganization Plan commenced in September 2022 and are expected to be substantially completed by January 31, 2023.

As a result of these events, the Company incurred the following restructuring and impairment charges, which are recorded in the condensed consolidated statements of operations and comprehensive loss (in thousands):

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	Three Months Ended September 30, 2022		Nine Months Ended September 30, 2022
Employee termination benefits	$	5,667	$	5,667
Impairment of property, plant and equipment	17,787		17,787
Contract termination costs	6,598		6,598
	$	30,052	$	30,052

Employee Termination Benefits

Employees affected by the reduction in workforce under the Company's Reorganization Plan obtained involuntary termination benefits that are provided pursuant to a one-time benefit arrangement. For employees who were notified of their termination in September 2022 and have no requirements to provide future service, the Company recognized the liability for the termination benefits in full at fair value in the current period. For employees who are required to render services beyond a minimum retention period to receive their one-time termination benefits, the Company is recognizing the termination benefits ratably over their future service periods. The service periods began in September 2022 and all will end at various dates through December 31, 2022. The Company expects that it will incur approximately $6.3 million of employee termination benefits expense to implement the Reorganization Plan.

The following table shows the liability related to employee termination benefits as of September 30, 2022:

	Employee Termination Benefits
Accrued employee termination benefits beginning balance	$	—
Employee termination benefits charges incurred during the period	5,667
Amounts paid or otherwise settled during the period	(763)
Accrued employee termination benefits as of September 30, 2022	$	4,904

Impairment of Property, Plant and Equipment

As a result of the Reorganization Plan, the Company determined that sufficient indicators exist to trigger the performance of an interim long-lived asset impairment analysis as of September 30, 2022. In the third quarter of 2022, the Company tested the recoverability of its asset group using entity-specific undiscounted cash flows. Based on these undiscounted cash flows, the Company concluded the undiscounted future cash flows expected to result from the use and eventual disposition of its long-lived assets were less than the carrying value of the asset group. Therefore, the Company measured the long-lived asset impairment as the amount by which the carrying value of the asset group exceeds its fair value. The loss was allocated to the long-lived assets of the group on a pro rata basis using the relative carrying amounts of those assets, except that the loss allocated to an individual long-lived asset of the group did not reduce the carrying value of that asset below its fair value. The fair value of the asset group was determined from a third-party commercial real estate appraisal which represents a Level 3 fair value measurement.

Additionally, in conjunction with its Reorganization Plan, the Company committed to a plan to actively sell specific assets within its asset group, primarily of its laboratory equipment and furniture and fixtures. The laboratory equipment and furniture and fixtures met all of the prescribed criteria required to classify it as held for sale. At September 30, 2022, $4.3 million of laboratory equipment and furniture and fixtures was classified as held for sale as current assets on the condensed consolidated balance sheet as the disposal is expected to be consummated within one year of the balance sheet date and the Company does not expect to use the sale proceeds to reduce any long-term borrowings. The sale is expected to be completed by January 31, 2023.

For the three and nine months ended September 30, 2022, the Company recorded impairment charges of $17.8 million. The long-lived asset impairment charge was recorded within restructuring and impairment charges on the condensed consolidated statements of operations and comprehensive loss and as a reduction to the related asset balances on the condensed consolidated balance sheets.

See Note 4 for property, plant and equipment, net and assets held for sale carrying amounts after the effects of impairment charges and held for sale reclassifications.

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Contract Termination Costs

The discontinuation of the RTX-240 and RTX-224 clinical trials resulted in the termination of vendor contracts before the end of their term, as well as costs that continue to be incurred under certain contracts with no future economic benefit to the Company. The Company recognized these contract termination costs in full in the current period. During the three and nine months ended September 30, 2022, the Company incurred $6.6 million of contract termination costs, which it estimates to be the full amount of such costs to be incurred related to the Reorganization Plan.

The following table shows the liability related to contract termination costs as of September 30, 2022:

	Contract Termination Costs
Accrued contract termination costs	$	—
Contract termination costs incurred during the period	6,598
Amounts paid or otherwise settled during the period	(2,007)
Accrued contract termination costs as of September 30, 2022	$	4,591

12. Subsequent Events

Strategic Plan

On November 2, 2022, the Company announced that, in light of the Company’s financial condition, including the repayment and termination of its $75.0 million credit facility with SLR Investment Corp., and the early stage of its programs, its Board of Directors approved a plan to review strategic alternatives, including a sale or merger of the Company or one or more sales of its assets, and to significantly and immediately reduce its operations. In connection with the Strategic Plan, the Company has terminated 42 of its employees (representing 82% of its current employee base), leaving a core team of individuals to lead the strategic review process.

The Company expects that these measures will reduce its operating expenses with the goal of allowing the Company to pursue any viable strategic alternatives. As a result of the Plan, the Company estimates that it will incur charges of approximately $4.4 million in the fourth quarter of 2022, which include termination benefits principally comprised of severance payments.

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Objective

The purpose of the following discussion and analysis is to provide material information relevant to an assessment of our financial condition and results of operations from management’s perspective, including to describe and explain key trends, events and other factors that impacted our reported results and that are reasonably likely to impact our future performance.

As such, the following discussion and analysis of our financial condition and results of operations should be read in conjunction with our condensed consolidated financial statements and related notes appearing elsewhere in this Quarterly Report on Form 10-Q and our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the Securities and Exchange Commission, or SEC, on February 25, 2022, and should also take into account our recently announced Strategic Plan described below. Some of the information contained in this discussion and analysis or set forth elsewhere in this Quarterly Report on Form 10-Q, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties, including risks associated with our Strategic Plan. As a result of many factors, including those factors set forth in the “Risk Factors” section of this Quarterly Report on Form 10-Q, 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.

Overview

We are a biopharmaceutical company that is developing an entirely new class of cellular medicines called RCTs, for the treatment of cancer and autoimmune diseases.

On November 2, 2022, we announced that, in light of our financial condition, including the repayment and termination of our $75.0 million credit facility with SLR Investment Corp., and the early stage of our programs, our Board of Directors approved a plan to review strategic alternatives, including a sale or merger of the Company or one or more sales of our assets, and to significantly and immediately reduce our operations (the “Strategic Plan”). In connection with the Strategic Plan, we have terminated 42 of our employees (representing 82% of our current employee base), leaving a core team of individuals to lead the strategic review process.

Our ability to pursue the research and clinical development activities and other initiatives discussed in this report will require significant funding, which is unlikely to be available, or may only be pursued if we are able to successfully complete a strategic alternative.

Although we have ceased enrolling patients, with more than 80 patients dosed across three clinical trials to date, we demonstrated that engineered red blood cells, or RBCs, can be manufactured at scale and observed initial evidence of tolerability clinical activity in certain cancer patients, including evidence of tumor shrinkage and prolonged stable disease in PD-(L)-1 refractory solid tumors. Based on these early findings, we firmly believe in the potential of RCTs for the treatment of cancer and autoimmune diseases.

Following careful review of recent technical progress in an alternative format for making RCTs, we believe that this alternative process has the potential for substantive improvements over our existing RED PLATFORM, and, therefore, continued investment in our two current clinical candidates is no longer justified. In September 2022, we announced a new strategic reorganization plan focused on advancing a next generation RBC-based cell conjugation platform and related cost-saving measures.

This next generation platform has the potential to improve upon the benefits of our existing RED PLATFORM, with the potential for greater efficacy and enhanced versatility, while maintaining a favorable tolerability profile. As a result, we have discontinued our ongoing Phase 1 clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors and restructured the organization to support advancing drug candidates based on the next generation platform.

Next Generation Red Blood Cell-Based Cell Conjugation Platform Overview

The next generation platform leverages chemical conjugation to produce RCTs. Cell conjugation creates a covalent link between the cell surface and the molecule of interest. Compared to our existing RED PLATFORM, this new approach is intended to:

•deliver a higher effective dose by enabling a longer circulation time and/or administering a higher cell dose;

•be more versatile, enabling the conjugation of different payloads, immunomodulatory agents, small molecules and proteins on the cell for enhanced potency; and

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•reduce the cost of goods manufacturing by utilizing blood-banked RBCs versus biologically engineering and differentiating early progenitor cells into reticulocytes that express proteins.

These attributes have the potential to result in greater efficacy, a similar safety profile given the restricted biodistribution of RBCs to the spleen and vasculature, and a significant reduction in overall cost structure.

Business & Strategy Update

To enable continued investment in the new platform, we had restructured our business and implemented a series of cost-saving measures. These measures include:

•implementing an approximately 75% reduction in workforce, primarily focused on clinical development, manufacturing and general and administrative personnel;

•discontinuing our ongoing Phase 1 clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors; and

•exploring the sale of our manufacturing facility in Smithfield, Rhode Island.

With these cost-saving measures, together with the implementation of the Strategic Plan, our operations are significantly reduced and will be focused on maintaining the new platform and related preclinical programs for purposes of exploring strategic alternatives.

Overview of Discontinued Clinical Programs

Phase 1/2 Clinical Trial of Monotherapy RTX-240

36 patients were dosed in the monotherapy arm of the Phase 1/2 clinical trial of RTX-240 in advanced solid tumors. One patient with renal cell carcinoma remained on study with stable disease for more than one year after developing progressive disease on prior treatment with nivolumab. This patient was dose-escalated from the 3e10 x 3 + 1e10 Q3W dose level to the 5e10 Q3W dose level after Cycle 12. To date, RTX-240 has been well tolerated with no treatment-related Grade 3/4 adverse events (AEs) and no dose-limiting toxicities.

Phase 1 Clinical Trial of RTX-240 + Pembrolizumab in Advanced Solid Tumors

Sixteen patients were dosed in the dose-escalation/expansion portion of the Phase 1 clinical trial evaluating RTX-240 in combination with pembrolizumab in advanced solid tumors. One colorectal cancer patient remained on study with stable disease of greater than 4 months. To date, the combination of RTX-240 with pembrolizumab has been well tolerated with no treatment or investigator-identified immune-related Grade 3/4 AEs and no dose-limiting toxicities.

Phase 1 Clinical Trial of RTX-224 in Select Advanced Solid Tumors

Seven patients were dosed across two dose cohorts in the Phase 1 clinical trial evaluating RTX-224 in select advanced solid tumors, including non-small cell lung cancer, cutaneous melanoma, head and neck squamous cell carcinoma, urothelial (bladder) carcinoma and triple-negative breast cancer. To date, there have been no treatment-related Grade 3/4 AEs and no dose-limiting toxicities.

Funding Overview

Since our inception, we have focused substantially all of our resources on building our proprietary RED PLATFORM, establishing and protecting our intellectual property portfolio, conducting research and development activities, developing our manufacturing process and manufacturing product candidate material, organizing and staffing our company, business planning, raising capital and providing general and administrative support for these operations. We do not have any products approved for sale and have not generated any revenue from product sales. To date, we have funded our operations with proceeds from the sale of preferred stock and issuance of debt and with proceeds from our public offerings.

On July 20, 2018, we completed our IPO pursuant to which we issued and sold 12,055,450 shares of common stock, inclusive of 1,572,450 shares pursuant to the full exercise of the underwriters’ option to purchase additional shares. We received proceeds of $254.3 million after deducting underwriting discounts and commissions and other offering costs. In August 2019, we entered into a Distribution Agreement with J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC with respect to an at-the-market, or ATM, offering program under which we were able to offer and sell, from time to time at our sole discretion, shares of our common stock, having aggregate gross proceeds of up to $100.0 million. No shares of common stock were issued and sold pursuant to the Distribution Agreement, which expired in accordance with its

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terms on August 21, 2022, and the applicable registration statement is no longer effective. In March 2021, we completed an underwritten public offering, or the March 2021 Offering, pursuant to which we issued and sold 6,896,552 shares of common stock. We received proceeds of $187.2 million, after deducting underwriting discounts and commissions and other offering costs. In October 2022, pursuant to a payoff letter, we voluntarily prepaid approximately $75.7 million, in full satisfaction of all obligations, including all outstanding principal, accrued interest, fees, costs, expenses and other amounts chargeable, under our loan agreement.

Since our inception, we have incurred significant operating losses. Our ability to generate any product revenue or product revenue sufficient to achieve profitability will depend on the successful development and eventual commercialization of one or more of our product candidates. We reported net losses of $159.5 million for the nine months ended September 30, 2022 and $196.5 million for the year ended December 31, 2021. As of September 30, 2022, we had an accumulated deficit of $836.5 million. Further, our cash resources have been significantly depleted due to the $75.7 million used to extinguish our long-term debt and satisfy our obligations under the loan and security agreement with SLR Investment Corp. As noted elsewhere in this report, there is substantial doubt as to our ability to fund our planned operations for the next twelve months and to continue to operate as a going concern. Further, our recently announced Strategic Plan will significantly reduce our operations. We expect to continue to incur significant expenses and operating losses for at least the next several years. If we were able to continue our operations long-term, we would expect that our expenses and capital requirements would increase in connection with our ongoing activities, particularly if, and as, we:

•continue to discover and develop additional product candidates;

•conduct preclinical studies and clinical trials for any product candidates we may develop and to the extent we continue to experience delays, setbacks or disruptions to our preclinical studies or supply chain due to the ongoing COVID-19 pandemic;

•further develop our next generation red blood cell-based conjugation platform;

•maintain, expand and protect our intellectual property portfolio;

•hire additional clinical, scientific, manufacturing and commercial personnel;

•establish a clinical and commercial manufacturing source and secure supply chain capacity sufficient to provide commercial quantities of any product candidates for which we may obtain regulatory approval;

•acquire or in-license other product candidates and technologies;

•seek regulatory approvals for any product candidates that successfully complete clinical trials;

•establish a sales, marketing and distribution infrastructure to commercialize any products for which we may obtain regulatory approval; and

•add operational, financial and management information systems and personnel, including personnel to support our product development and planned future commercialization efforts, as well as to continue to support the requirements of a public company.

We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for any product candidates we may develop. If we obtain regulatory approval for any such product candidates, we expect to incur significant expenses related to developing our commercialization capability to support product sales, marketing and distribution. Further, we expect to continue to incur costs associated with operating as a public company.

As a result of the Reorganization and Strategic Plans, our current financial resources and currently forecasted operating plan would allow us to operate into the first quarter of 2023. We expect our Strategic Plan will reduce our operating expenses with the goal of allowing us to pursue any viable strategic alternatives. There is no guarantee that this plan will be successful. We may not be able to successfully pursue any strategic alternatives and, even if certain strategic alternatives may be available, we cannot provide any assurance that the strategic alternatives review process will result in any particular alternative, transaction or value.

As of September 30, 2022, we had an accumulated deficit of $836.5 million, and cash and cash equivalents of $103.9 million. For the nine months ended September 30, 2022, we incurred a loss of $159.5 million and used $117.6 million of cash in operations. We expect that our operating losses and negative cash flows will continue for the foreseeable future. We

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have assessed our ability to continue as a going concern, and, based on our recurring losses from operations incurred since inception, expectation of continuing operating losses for the foreseeable future, and the need to raise additional capital to finance our future operations, as of November 9, 2022, the issuance date of the interim condensed consolidated financial statements for the three and nine month periods ended September 30, 2022, we have concluded that there is substantial doubt about our ability to continue as a going concern for a period of one year from the date that these condensed consolidated financial statements are issued.

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. Even if we are able to continue operations beyond the next twelve months, 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.

See “—Liquidity and Capital Resources.”

Nasdaq Delisting Notification

On July 27, 2022, we received a deficiency letter from the Listing Qualifications Department, or the Staff, of The Nasdaq Stock Market LLC, or Nasdaq, notifying us that, for the last 30 consecutive business days, the bid price for our common stock had closed below the $1.00 per share minimum bid price requirement for continued inclusion on the Nasdaq Global Select Market pursuant to Nasdaq Listing Rule 5450(a)(1) (which we refer to as the “Minimum Bid Price Requirement”). The Nasdaq deficiency letter has no immediate effect on the listing of our common stock, and our common stock will continue to trade on the Nasdaq Global Select Market under the symbol “RUBY” at this time.

In accordance with Nasdaq Listing Rule 5810(c)(3)(A), or the Compliance Period Rule, we have been provided a period of 180 calendar days, or until January 23, 2023 (which we refer to as the “Compliance Date”), to regain compliance with the Minimum Bid Price Requirement. If, at any time ending January 23, 2023, the bid price for our common stock closes at $1.00 or more for a minimum of ten consecutive business days, as required under the Compliance Period Rule, the Staff will provide written notification to us that we have regained compliance with the Minimum Bid Price Requirement and our common stock will continue to be eligible for listing on the Nasdaq Global Select Market, unless the Staff exercises its discretion to extend this ten-day period pursuant to Nasdaq Listing Rule 5810(c)(3)(H).

If we do not regain compliance with the Minimum Bid Price Requirement by the Compliance Date, we may be eligible for an additional 180 calendar day compliance period. To qualify, we would need to transfer the listing of our common stock to The Nasdaq Capital Market, provided that we meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, with the exception of the Minimum Bid Price Requirement, and would need to provide written notice to Nasdaq of our intention to cure the deficiency during the additional compliance period. To effect such a transfer, we would also need to pay an application fee to Nasdaq and provide written notice to the Staff of our intention to cure the deficiency during the second compliance period by effecting a reverse stock split if necessary. As part of its review process, the Staff will make a determination of whether it believes we will be able to cure the deficiency. Should the Staff conclude that we will not be able to cure the deficiency, the Staff will provide written notification to us that our common stock will be subject to delisting. At that time, we may appeal the Staff’s delisting determination to a Nasdaq Listing and Hearing Review Panel. However, there can be no assurance that, if we receive a delisting notice and appeal the delisting determination by the Staff to the panel, such appeal would be successful.

We intend to monitor the closing bid price of our common stock and may, if appropriate, consider available options to regain compliance with the Minimum Bid Price Requirement, which could include seeking to effect a reverse stock split. However, there can be no assurance that we will be able to regain, or even pursue, compliance with the Minimum Bid Price Requirement, secure a second period of 180 days to regain compliance, or maintain compliance with any of the other Nasdaq continued listing requirements.

Impact of the Ongoing COVID-19 Pandemic

Since March of 2020 and throughout the ongoing COVID-19 pandemic, we have implemented various precautionary measures to protect the health and safety of our employees, partners and prospective clinical trial participants, to comply with applicable national, state and local governmental orders, proclamations and/or directives in effect at any time aimed at minimizing the spread of COVID-19 and to minimize disruption to our operations. Such measures have included, at certain times, the elimination of business travel, shifting to remote work wherever possible and implementing rotating laboratory work schedules to reduce the number of people onsite at our facilities, advance ordering of certain raw materials impacted

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by delays in the global supply chain, as well as working with our external partners and clinical sites to utilize virtual clinical trial site training and monitoring, minimizing patient visits and instituting telemedicine to minimize patient exposure. We will continue to use these, and other precautionary measures, as required until such time as the ongoing COVID-19 pandemic, including any subsequent outbreak whether or not due to emerging variants thereof, is contained.

While the ongoing COVID-19 pandemic has impacted manufacturing, supply chain and clinical trial activities worldwide, including those of our suppliers, vendors and clinical trial sites, these disruptions have not significantly impacted our results of operations to date. The ultimate impact on our operations, however, is unknown and will depend on future developments, such as the duration, spread and intensity of the pandemic, among others, which are highly uncertain and cannot be predicted with confidence. In particular, global developments concerning COVID-19, including the identification of new strains of coronavirus, and the magnitude of interventions to contain the spread of viruses, such as government-mandated quarantines, shelter-in-place mandates, restrictions on travel, shutdowns for non-essential businesses, requirements regarding social distancing, impact of government-imposed restrictions on the global supply chain, including through use of the Defense Production Act, distribution of vaccines and other public health safety measures, will determine the impact of the pandemic on our business. We are continuing to monitor the latest developments regarding the ongoing COVID-19 pandemic and its impact on our business, financial condition, results of operations and prospects. However, any resulting financial impact cannot be reasonably estimated at this time and may 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 product sales and do not expect to generate any revenue from the sale of products in the near future. If our development efforts for our potential product candidates are successful and result in regulatory approval or license or collaboration agreements with third parties, we may generate revenue in the future from product sales, payments from collaboration or license agreements that we may enter into with third parties, or any combination thereof.

Operating Expenses

Research and Development Expenses

Research and development expenses consist of costs incurred for our research activities, including our drug discovery efforts, and the development and manufacturing of our pipeline products and discontinued product candidates, which include:

•employee-related expenses, including salaries, related benefits and stock-based compensation expense for employees engaged in research and development functions;

•expenses incurred in connection with the preclinical and clinical development of future product candidates and wind-down of our discontinued product candidates and research programs, including under agreements with third parties, such as consultants, contractors and contract research organizations, or CROs;

•the cost of developing and scaling our manufacturing process and manufacturing future product candidates and discontinued product candidates for use in our preclinical studies and clinical trials, including those produced in our manufacturing facility as well as components that are produced under agreements with third parties, such as consultants, contractors and any contract manufacturing organizations, or CMOs, that we may engage;

•laboratory supplies and research materials;

•facilities, depreciation and other expenses, which include direct and allocated expenses for rent and maintenance of facilities and insurance; and

•payments made under third-party licensing agreements.

We expense research and development costs as incurred. 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. The prepaid amounts are expensed as the related goods are delivered or the services are performed.

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Our direct research, manufacturing and development expenses are tracked on a program-by-program basis. These consist mostly of fees, reimbursed materials, testing and other costs paid to consultants, contractors, CMOs and CROs, as well as the cost of materials incurred for internal manufacturing. In addition, we allocate the cost of operating our manufacturing facility to research and development program costs, consisting of associated personnel costs, other than stock-based compensation expense, and manufacturing facility costs, including depreciation. We do not allocate costs associated with our platform development, early-stage research and shared research and development, including associated personnel costs, laboratory supplies, non-manufacturing facilities expenses and other indirect costs, to research and development programs, because these costs are deployed across multiple programs and our technology platform and, as such, are not separately classified.

The successful development and commercialization of our potential product candidates is highly uncertain. This is due to the numerous risks and uncertainties associated with product development and commercialization, including the following:

•the timing and progress of preclinical and clinical development activities;

•the number and scope of preclinical and clinical programs we decide to pursue;

•our ability to raise the additional funds necessary to complete preclinical and clinical development of and commercialize our drug candidates;

•the progress of the development efforts of parties with whom we may enter into collaboration arrangements;

•our ability to maintain our current research and development programs and to establish new ones;

•our ability to establish new licensing or collaboration arrangements;

•the successful initiation and completion of clinical trials with safety, tolerability and efficacy profiles that are satisfactory to the U.S. Food and Drug Administration, or FDA, or any comparable foreign regulatory authority;

•the continued impact of the ongoing COVID-19 pandemic on our operations;

•the receipt and related terms of regulatory approvals from applicable regulatory authorities;

•the availability of specialty raw materials for use in production of our product candidates;

•our ability to consistently manufacture any product candidates we may develop for use in future clinical trials;

•our ability to secure manufacturing supply through relationships with third parties;

•our ability to obtain and maintain patents, trade secret protection and regulatory exclusivity, both in the United States and internationally;

•our ability to protect our rights in our intellectual property portfolio;

•our ability to successfully commercialize any product candidates we may develop, if and when approved;

•our ability to obtain and maintain third-party insurance coverage and adequate reimbursement;

•the acceptance of any product candidates we may develop, if approved, by patients, the medical community and third-party payors;

•competition with other products; and

•a continued acceptable safety profile of our therapies following approval.

A change in the outcome of any of these variables with respect to the development of any of product candidates we may develop could significantly change the costs and timing associated with the development of that product candidate. We may never succeed in obtaining regulatory approval for any of our product candidates.

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General and Administrative Expenses

General and administrative expenses include salaries and related costs, including stock-based compensation, for personnel in executive, finance and administrative functions. General and administrative expenses also include direct and allocated facility-related costs, as well as professional fees for legal, patent, consulting, investor and public relations, accounting and audit services.

Restructuring and Impairment Charges

In September 2022, the Company undertook certain operational and organizational steps in connection with our new strategic Reorganization Plan and related cost-saving measures. These measures included discontinuing the ongoing clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors and reducing the Company's overall workforce by approximately 75%.

Other Income (Expense)

Interest Income

Interest income consists of interest earned on our invested cash balances.

Interest Expense

Interest expense consists of interest owed on outstanding borrowings under our Loan Agreement (as defined below), as well as amortization of debt discount.

Other Income, Net

Other income, net consists of miscellaneous income and expense unrelated to our core operations.

Income Taxes

Since our inception, we have not recorded any income tax benefits for the net losses we have incurred in each year or for our research and development tax credits generated, as we believe, based upon the weight of available evidence, that it is more likely than not that all of our net operating loss, or NOL, carryforwards and tax credits will not be realized. As of December 31, 2021, we had U.S. federal and state net operating loss carryforwards of $534.2 million and $534.8 million, respectively, which may be available to offset future taxable income. The federal NOLs include $37.2 million, which expire at various dates through 2037, and $497.0 million, which carryforward indefinitely. The state NOLs expire at various dates through 2041. As of December 31, 2021, we also had U.S. federal and state research and development tax credit carryforwards of $22.7 million and $15.6 million, respectively, which may be available to offset future tax liabilities and begin to expire in 2034 and 2026, respectively. We have recorded a full valuation allowance against our net deferred tax assets at each balance sheet date.

Results of Operations

Comparison of the Three Months Ended September 30, 2022 and 2021

The following table summarizes our results of operations for the three months ended September 30, 2022 and 2021:

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	Three Months Ended September 30,
	2022		2021		Change
	(in thousands)
Revenue	$	—	$	—	$	—
Operating expenses:
Research and development	24,229		38,014		(13,785)
General and administrative	7,301		12,035		(4,734)
Restructuring and impairment charges	30,052		—		30,052
Total operating expenses	61,582		50,049		11,533
Loss from operations	(61,582)		(50,049)		(11,533)
Other income (expense):
Interest income	392		23		369
Interest expense	(1,736)		(1,711)		(25)
Other income, net	53		2,721		(2,668)
Total other income (expense), net	(1,291)		1,033		(2,324)
Net loss	$	(62,873)	$	(49,016)	$	(13,857)

Research and Development Expenses

	Three Months Ended September 30,
	2022		2021		Change
	(in thousands)
Research and development program expenses:
Cancer	$	11,061	$	20,181	$	(9,120)
Platform development, early-stage research and unallocated expenses:
Personnel-related	3,824		7,111		(3,287)
Stock-based compensation expense	2,266		3,408		(1,142)
Contract research and development	2,297		2,242		55
Laboratory supplies and research materials	1,096		1,226		(130)
Facility-related and other	3,685		3,846		(161)
Total research and development expenses	$	24,229	$	38,014	$	(13,785)

Research and development expenses were $24.2 million for the three months ended September 30, 2022, compared to $38.0 million for the three months ended September 30, 2021. The decrease in research and development program expenses of $9.1 million relates to the deprioritization of RTX-321 and RTX-240 AML and monotherapy studies. This decrease was partially offset by an increase in clinical costs related to RTX-224 that were incurred prior to the discontinuation of the ongoing clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors. We expect these costs to continue to decrease in future periods due to the discontinuation of these clinical trials. Platform development, early-stage research and unallocated expenses decreased by $4.7 million primarily due to a decrease of $3.3 million in personnel-related expenses due to headcount reductions in research and development functions during 2022 and a $1.1 million reduction in stock-based compensation expense related to the decrease in the market price of our common stock, resulting in a lower valuation of stock options granted in 2022. Additionally, facility-related and other expenses decreased by $0.2 million related to lower spend on non-capitalized software costs and a reduction in building operating costs in the current year.

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General and Administrative Expenses

	Three Months Ended September 30,
	2022		2021		Change
	(in thousands)
Personnel-related	$	1,859	$	3,408	$	(1,549)
Stock-based compensation expense	1,532		4,781		(3,249)
Professional and consultant fees	2,228		2,230		(2)
Facility-related and other	1,682		1,616		66
Total general and administrative expenses	$	7,301	$	12,035	$	(4,734)

General and administrative expenses were $7.3 million for the three months ended September 30, 2022, compared to $12.0 million for the three months ended September 30, 2021. The decrease in general and administrative expenses of $4.7 million was primarily due to a decrease in stock-based compensation expense of $3.2 million, which was driven by stock option awards that fully vested during the second half of 2021 and first half of 2022, as well as a reduction in the market price of our common stock, resulting in a lower valuation of stock options granted in 2022. Additionally, personnel-related expenses decreased by $1.5 million due to headcount reductions in general and administrative functions during 2022.

Restructuring and Impairment Charges

	Three Months Ended September 30,
	2022		2021		Change
	(in thousands)
Employee termination benefits	$	5,667	$	—	$	5,667
Impairment of property, plant and equipment	17,787		—		17,787
Contract termination costs	6,598		—		6,598
Total restructuring and impairment charges	$	30,052	$	—	$	30,052

During the three months ended September 30, 2022, we recorded charges of $5.7 million, $17.8 million and $6.6 million related to employee termination benefits, impairment of property, plant and equipment and contract termination costs, respectively, due to the strategic Reorganization Plan we initiated in the third quarter of 2022. We paid or otherwise settled $2.8 million of employee termination benefits and contract termination costs during the three months ended September 30, 2022 and expect to pay or otherwise settle approximately $12.9 million in total to implement the strategic Reorganization Plan.

Interest Income

Interest income was $0.4 million for the three months ended September 30, 2022, compared to less than $0.1 million for the three months ended September 30, 2021. Interest income increased due to higher prevailing interest rates.

Interest Expense

Interest expense was $1.7 million for the three months ended September 30, 2022, compared to $1.7 million for the three months ended September 30, 2021. The change in interest expense was not significant during the period.

Other Income, Net

Other income, net was $0.1 million for the three months ended September 30, 2022, compared to $2.7 million for the three months ended September 30, 2021. The decrease in other income, net was due to the monetization of certain tax credits during the prior period.

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Comparison of the Nine Months Ended September 30, 2022 and 2021

The following table summarizes our results of operations for the nine months ended September 30, 2022 and 2021:

	Nine Months Ended September 30,
	2022		2021		Change
	(in thousands)
Revenue	$	—	$	—	$	—
Operating expenses:
Research and development	95,526		101,763		(6,237)
General and administrative	29,772		39,126		(9,354)
Restructuring and impairment charges	30,052		—		30,052
Total operating expenses	155,350		140,889		14,461
Loss from operations	(155,350)		(140,889)		(14,461)
Other income (expense):
Interest income	695		75		620
Interest expense	(4,995)		(4,771)		(224)
Other income, net	124		4,059		(3,935)
Total other income (expense), net	(4,176)		(637)		(3,539)
Net loss	$	(159,526)	$	(141,526)	$	(18,000)

Research and Development Expenses

	Nine Months Ended September 30,
	2022		2021		Change
	(in thousands)
Research and development program expenses:
Rare disease	$	—	$	197	$	(197)
Cancer	44,990		51,778		(6,788)
Platform development, early-stage research and unallocated expenses:
Personnel-related	20,057		20,437		(380)
Stock-based compensation expense	7,959		8,995		(1,036)
Contract research and development	7,052		5,278		1,774
Laboratory supplies and research materials	4,707		3,791		916
Facility-related and other	10,761		11,287		(526)
Total research and development expenses	$	95,526	$	101,763	$	(6,237)

Research and development expenses were $95.5 million for the nine months ended September 30, 2022, compared to $101.8 million for the nine months ended September 30, 2021. The decrease in research and development program expenses of $7.0 million related to the deprioritization of RTX-321 and RTX-240 AML and monotherapy studies. This decrease was partially offset by an increase in clinical costs related to RTX-224 that were incurred prior to the discontinuation of the ongoing clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors. We expect these costs to continue to decrease in future periods due to the discontinuation of these clinical trials. Platform development, early-stage research and unallocated expenses increased by $0.7 million principally due to an increase of $1.8 million in contract research and development and $0.9 million in laboratory supplies and research materials for drug discovery activities and platform development. These increases were offset by a decrease of $1.0 million in stock-based compensation expenses related to the decrease in the market price of our common stock, resulting in a lower valuation of stock options granted in 2022, and a reduction in facility-related and other expenses of $0.5 million due to lower spend on non-capitalized software costs and a reduction in building operating costs in the current year.

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General and Administrative Expenses

	Nine Months Ended September 30,
	2022		2021		Change
	(in thousands)
Personnel-related	$	8,741	$	9,961	$	(1,220)
Stock-based compensation expense	9,141		17,433		(8,292)
Professional and consultant fees	6,910		6,745		165
Facility-related and other	4,980		4,987		(7)
Total general and administrative expenses	$	29,772	$	39,126	$	(9,354)

General and administrative expenses were $29.8 million for the nine months ended September 30, 2022, compared to $39.1 million for the nine months ended September 30, 2021. The decrease in general and administrative expenses of $9.4 million was primarily due to a decrease in stock-based compensation expense of $8.3 million, which was driven by stock option awards that fully vested during the second half of 2021 and first half of 2022, as well as a reduction in the market price of our common stock, resulting in a lower valuation of stock options granted in 2022. Additionally, personnel-related expenses decreased by $1.2 million driven by headcount reductions in general and administrative functions during 2022.

Restructuring and Impairment Charges

	Nine Months Ended September 30,
	2022		2021		Change
	(in thousands)
Employee termination benefits	$	5,667	$	—	$	5,667
Impairment of property, plant and equipment	17,787		—		17,787
Contract termination costs	6,598		—		6,598
Total restructuring and impairment charges	$	30,052	$	—	$	30,052

During the nine months ended September 30, 2022, we recorded charges of $5.7 million, $17.8 million and $6.6 million related to employee termination benefits, impairment of property, plant and equipment and contract termination costs, respectively, due to the strategic Reorganization Plan we initiated in the third quarter of 2022. We paid or otherwise settled $2.8 million of employee termination benefits and contract termination costs during the three months ended September 30, 2022 and expect to pay or otherwise settle approximately $12.9 million in total to implement the strategic Reorganization Plan.

Interest Income

Interest income was $0.7 million for the nine months ended September 30, 2022, compared to $0.1 million for the nine months ended September 30, 2021. Interest income increased due to higher prevailing interest rates.

Interest Expense

Interest expense was $5.0 million for the nine months ended September 30, 2022, compared to $4.8 million for the nine months ended September 30, 2021. Interest expense increased due to higher prevailing interest rates.

Other Income, Net

Other income, net was $0.1 million for the nine months ended September 30, 2022, compared to $4.1 million for the nine months ended September 30, 2021. The decrease in other income, net was principally due to the monetization of certain tax credits during the prior period.

Liquidity and Capital Resources

Since our inception, we have incurred significant operating losses. We have not yet commercialized any product candidates and we do not expect to generate revenue from sales of any product candidates we may develop for several years, if at all.

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To date, we have funded our operations with proceeds from the sale of preferred stock, with the issuance of debt, with proceeds from our IPO and, most recently, with proceeds from our March 2021 Offering, described and defined further below. In July 2018, we completed our IPO, pursuant to which we issued and sold 12,055,450 shares of common stock, inclusive of 1,572,450 shares pursuant to the full exercise of the underwriters’ option to purchase additional shares. We received proceeds of $254.3 million, after deducting underwriting discounts and commissions and other offering costs. In December 2018, we entered into a loan and security agreement, which was amended in June 2021, and provides for aggregate borrowings of up to $75.0 million. As of September 30, 2022, $75.0 million was outstanding under the agreement. In March 2021, we completed the March 2021 Offering, pursuant to which we issued and sold 6,896,552 shares of common stock. We received proceeds of $187.2 million, after deducting underwriting discounts and commissions and other offering costs. As of September 30, 2022, we had cash and cash equivalents of $103.9 million. In October 2022, pursuant to a payoff letter, we voluntarily prepaid approximately $75.7 million, in full satisfaction of all obligations, including all outstanding principal, accrued interest, fees, costs, expenses and other amounts chargeable, under the Loan Agreement, considerably depleting our cash resources. As noted elsewhere in this report, there is substantial doubt as to our ability to fund our planned operations for the next twelve months and to continue to operate as a going concern, and we have recently announced our Strategic Plan which significantly reduced our operations, which will be focused on pursuing strategic alternatives.

Cash Flows

The following table summarizes our sources and uses of cash for each of the periods presented:

	Nine Months Ended September 30,
	2022		2021
	(in thousands)
Cash used in operating activities	$	(117,625)	$	(107,905)
Cash provided by (used in) investing activities	(4,733)		82,720
Cash provided by financing activities	232		198,037
Net increase (decrease) in cash, cash equivalents and restricted cash	$	(122,126)	$	172,852

Operating Activities

During the nine months ended September 30, 2022, operating activities used $117.6 million of cash, primarily resulting from our net loss of $159.5 million, offset by net non-cash charges of $41.0 million, predominantly consisting of impairment charges and stock-based compensation expense. Net cash used in our operating assets and liabilities for the nine months ended September 30, 2022 consisted of a net increase in prepaid expenses and other current assets, operating lease, and right-of-use assets of $5.0 million, offset by an $4.1 million decrease in accounts payable, accrued expenses and other current liabilities, other long-term liabilities and operating lease liabilities.

During the nine months ended September 30, 2021, operating activities used $107.9 million of cash, primarily resulting from our net loss of $141.5 million, offset by net non-cash charges of $31.9 million, predominantly consisting of stock-based compensation expense. Net cash used in our operating assets and liabilities for the nine months ended September 30, 2021 consisted of a $1.2 million decrease in accounts payable, accrued expenses and other current liabilities, other long-term liabilities and operating lease liabilities, offset by a decrease in prepaid expenses and other current assets and operating lease, right-of-use asset of $2.9 million.

Investing Activities

During the nine months ended September 30, 2022, net cash used in investing activities was $4.7 million, consisting of purchases of investments of $78.4 million and purchases of property, plant and equipment of $5.0 million, offset by sales and maturities of investments of $78.8 million. Our cash purchases of property, plant and equipment primarily relate to the purchase of computer and laboratory equipment installed in our manufacturing facility in Smithfield, Rhode Island and our laboratory space in Cambridge, Massachusetts.

During the nine months ended September 30, 2021, net cash provided by investing activities was $82.7 million, consisting of sales and maturities of investments of $85.0 million, offset by purchases of property, plant and equipment of $2.3 million. Our cash purchases of property, plant and equipment primarily relate to the purchase of computer and laboratory equipment installed in our manufacturing facility in Smithfield, Rhode Island and our laboratory space in Cambridge, Massachusetts.

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Financing Activities

During the nine months ended September 30, 2022, net cash provided by financing activities of $0.2 million consisted of proceeds received from issuance of common stock upon exercise of stock options of $0.2 million.

During the nine months ended September 30, 2021, net cash provided by financing activities of $198.0 million consisted primarily of proceeds of $187.2 million, after deducting underwriting discounts and commissions and other offering costs, from the March 2021 Offering, as well as proceeds received from issuance of common stock upon exercise of stock options of $10.5 million. Net cash used in financing activities includes $0.4 million of offering cost payments in connection with the March 2021 Offering and $0.2 million of debt issuance cost payments related to our Loan Agreement in June 2021.

Contractual Obligations and Commitments

The following table summarizes our contractual obligations as of September 30, 2022 and the effects that such obligations are expected to have on our liquidity and cash flows in future periods:

	Payments Due by Period
	Total		Less Than 1 Year		1 to 3 Years		4 to 5 Years		More Than 5 Years
	(in thousands)
Operating lease commitments (1)	$	40,735	$	9,212	$	15,311	$	7,985	$	8,227
Debt obligations (2)	96,005		6,100		56,851		33,054		—
Total	$	136,740	$	15,312	$	72,162	$	41,039	$	8,227

(1)    Amounts in table reflect payments due for our leases of office and laboratory space in Cambridge, Massachusetts under two operating lease agreements that expire in January 2027 and August 2028, respectively.

(2)    Amounts in table reflect the contractually required principal and interest payments payable under the Loan Agreement. For purposes of this table, the interest due under the Loan Agreement was calculated using an assumed interest rate of 9.39% per annum, which was the interest rate in effect as of September 30, 2022.

Loan and Security Agreement

In December 2018, or the Closing Date, we entered into a loan and security agreement (the Original Loan Agreement, or, as amended, the Loan Agreement) with SLR Investment Corp., or SLR, (formerly Solar Capital Ltd.) as collateral agent for the lenders party thereto for an aggregate principal amount of $75.0 million. The aggregate principal amount was funded in three tranches of term loans of $25.0 million each, on the Closing Date, in June 2019, and in June 2020. On October 13, 2022, we entered into a payoff letter with SLR, under which we voluntarily prepaid SLR approximately $75.7 million, in full satisfaction of all obligations, including all outstanding principal, accrued interest, fees, costs, expenses and other amounts chargeable, under the Loan Agreement. The payoff letter also provided for the termination of all commitments and obligations under the Loan Agreement and release of all liens held by SLR on our assets.

Common Stock Sales Agreement

On August 1, 2019, we entered into a Distribution Agreement, or the Distribution Agreement, with multiple sales agents, pursuant to which the Company was able to offer and sell to or through the agents, from time to time, shares of the Company's common stock, par value $0.001 per share, having an aggregate gross sales price of up to $100.0 million. No shares of the Company's common stock were sold under the Distribution Agreement, which expired in accordance with its terms on August 21, 2022, and the applicable registration statement is no longer effective.

Funding Requirements

If we conduct the activities necessary to advance potential product candidates through development our expenses, to the extent we are able to support such operations, will increase substantially. The timing and amount of our operating and capital expenditures will depend largely on:

•the timing and progress of preclinical and clinical development activities;

•the commencement, enrollment or results of any future clinical trials we may conduct, or changes in the development status of any future product candidates;

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•the timing and outcome of regulatory review of any product candidates we may develop;

•the continued impact of the ongoing COVID-19 pandemic, including from any subsequent outbreak whether or not due to emerging variants thereof, on our operations;

•our decision to initiate a clinical trial, not to initiate a clinical trial or to terminate an existing clinical trial;

•changes in laws or regulations applicable to any product candidates we may develop, including but not limited to clinical trial requirements for approvals;

•developments concerning our key vendors;

•our ability to obtain materials to produce adequate product supply for any approved product or inability to do so at acceptable prices;

•the costs associated with manufacturing clinical supply of any product candidates we may develop;

•our ability to establish collaborations if needed;

•the costs and timing of future commercialization activities, including product manufacturing, marketing, sales and distribution, for any of our product candidates for which we obtain marketing approval;

•the legal patent costs involved in prosecuting patent applications and enforcing patent claims and other intellectual property claims;

•additions or departures of key scientific or management personnel;

•unanticipated serious safety concerns related to the use of our product candidates; and

•the terms and timing of any collaboration, license or other arrangement, including the terms and timing of any milestone payments thereunder.

Until such time, if ever, as we can generate substantial product revenue, we would need to finance our operations through a combination of public and private equity financings, debt financings, liquidation of assets no longer in use, strategic alliances and marketing, distribution and licensing arrangements, and our ability to do so is highly speculative. To the extent that we are able to raise additional capital through the sale of equity or convertible debt securities (which is unlikely given our current financial position), investors’ ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect investors’ rights as a common stockholder. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. If we raise additional funds through strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or drug candidates, or grant licenses on terms that may not be favorable to us. We implemented certain cost reduction actions in September 2022, which are intended to focus our capital on advancing our next generation red blood cell technology platform. If we are unable to obtain additional funding, we will implement further cost reduction actions that will delay, scale back or discontinue some or all of our research and development programs and technology platform activities in order to preserve cash. These actions are likely to adversely affect our business prospects.

As of September 30, 2022, we had an accumulated deficit of $836.5 million, and cash and cash equivalents of $103.9 million. For the nine months ended September 30, 2022, we incurred a loss of $159.5 million and used $117.6 million of cash in operations. We expect that our operating losses and negative cash flows will continue for the foreseeable future. We have assessed our ability to continue as a going concern and, based on our recurring losses from operations incurred since inception, the early payoff of our SLR Loan Agreement, expectation of continuing operating losses for the foreseeable future, and the need to raise additional capital to finance our future operations (which will be challenging if not impossible given our financial position), as of November 9, 2022, the issuance date of the interim condensed consolidated financial statements for the three and nine month periods ended September 30, 2022, we have concluded that there is substantial doubt about our ability to continue as a going concern for a period of one year from the date that these condensed consolidated financial statements are issued.

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Off-Balance Sheet Arrangements

We did not have during the periods presented, and we do not currently have, any off-balance sheet arrangements, as defined in the rules and regulations of the SEC.

Critical Accounting Policies and Significant Judgments and Estimates

Our condensed consolidated financial statements are prepared in accordance with generally accepted accounting principles in the United States, or GAAP. The preparation of our condensed consolidated financial statements and related disclosures requires us to make estimates, assumptions and judgments that affect the reported amounts of assets, liabilities, revenue, costs and expenses, and related disclosures. Our critical accounting policies are described under the heading “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Significant Judgments and Estimates” in our Annual Report on Form 10-K for the year ended December 31, 2021, filed with the SEC on February 25, 2022. If actual results or events differ materially from the estimates, judgments and assumptions used by us in applying these policies, our reported financial condition and results of operations could be materially affected.

There have been no significant changes to our critical accounting policies from those described in our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on February 25, 2022.

Recently Issued Accounting Pronouncements

A description of recently issued accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our condensed consolidated financial statements appearing elsewhere in this Quarterly Report on Form 10-Q.

Item 3. Quantitative and Qualitative Disclosures About Market Risk.

As of September 30, 2022, we had cash and cash equivalents of $103.9 million, which consisted of cash and money market accounts. Interest income is sensitive to changes in the general level of interest rates; however, due to the nature of these investments, an immediate 10% change in interest rates would not have a material effect on the fair market value of our investment portfolio.

As of September 30, 2022, we had $75.0 million of borrowings outstanding under the Loan Agreement. Interest on the outstanding borrowings under the Loan Agreement accrues at a rate of 5.50%, plus the greater of 2.10% or the one-month U.S. LIBOR rate. An immediate 10% change in the one-month U.S. LIBOR rate would not have a material impact on our debt-related obligations, financial position or results of operations.

On October 13, 2022, we entered into a payoff letter with SLR, under which we voluntarily prepaid SLR approximately $75.7 million, in full satisfaction of all obligations, including all outstanding principal, accrued interest, fees, costs, expenses and other amounts chargeable, under the Loan Agreement. The payoff letter also provided for the termination of all commitments and obligations under the Loan Agreement and release of all liens held by SLR on our assets.

We are not currently exposed to significant market risk related to changes in foreign currency exchange rates; however, we have contracted with and may continue to contract with foreign vendors that are located in Europe, Canada and China. Our operations may be subject to fluctuations in foreign currency exchange rates in the future.

Inflation generally affects us by increasing our cost of labor, research supplies and materials and manufacturing raw materials. We do not believe that inflation had a material effect on our business, financial condition or results of operations during the nine months ended September 30, 2022.

Item 4. Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer (our principal executive officer and principal financial officer, respectively), evaluated the effectiveness of our disclosure controls and procedures as of September 30, 2022. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act means controls and other procedures of an issuer that are designed to ensure that information required to be disclosed by an issuer in the reports that it files or submits under the Exchange Act is recorded,

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processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by an issuer in the reports that it files or submits under the Exchange Act is accumulated and communicated to the issuer’s management, including its principal executive and principal financial officers, or persons performing similar functions, as appropriate 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. Based on the evaluation of our disclosure controls and procedures as of September 30, 2022, 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.

Changes in Internal Control over Financial Reporting

There were no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the quarter ended September 30, 2022 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II — OTHER INFORMATION

Item 1. Legal Proceedings

We are not currently a party to any material legal proceedings.

Item 1A. Risk Factors

Our business is subject to numerous risks. You should carefully consider the risks described below, as well as the other information in this Quarterly Report on Form 10-Q, including our condensed consolidated financial statements and the related notes and “Management’s discussion and analysis of financial condition and results of operations,” and in our other filings with the Securities and Exchange Commission. The occurrence of any of the events or developments described below could harm our business, financial condition, results of operations and growth prospects. In such an event, the market price of our common stock could decline and you may lose all or part of your investment. Additional risks and uncertainties not presently known to us or that we currently deem immaterial also may impair our business operations.

Risks related to our financial condition and capital requirements

We do not currently have sufficient working capital to fund our planned operations for the next twelve months and may not be able to continue as a going concern, and our cash has been significantly depleted by our recent payoff of the SLR loan. Further, we have recently announced a strategic plan, which significantly reduced our operations to focus on our pursuit of strategic alternatives.

As of November 9, 2022, the issuance date of the interim condensed consolidated financial statements, there is substantial doubt about our ability to continue as a going concern, as we currently do not have adequate financial resources to fund our forecasted operating costs for at least twelve months from the filing of this Quarterly Report on Form 10-Q. As of September 30, 2022, we have incurred a cumulative net loss of $836.5 million. During the nine months ended September 30, 2022, we recorded a net loss of $159.5 million. In addition, during the nine months ended September 30, 2022, we used $122.4 million in operating and investing activities resulting in a cash and cash equivalents balance of $103.9 million as of September 30, 2022, without taking into account the early payoff of our SLR Loan Agreement, which used $75.7 million of our available cash and cash equivalents. As a result, our existing cash resources are not sufficient to meet our anticipated needs over the next twelve months from the date hereof, even after taking into account our significantly reduced operations, and we would need to raise additional capital to continue our operations and to implement our business plan, which capital is unlikely to be available on favorable terms or at all.

Our operating history and near-term forecast of incurring net losses and negative operating cash flows raise substantial doubt about our ability to continue as a going concern. If we raise funds from the issuance of equity securities (which will be challenging if not impossible in light of our financial position), substantial dilution to our existing stockholders would likely result. If we raise additional funds by incurring debt financing (also challenging in light of our financial position), the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict our ability to operate our business. Further, any contracts or license arrangements we enter into to raise funds may require us to relinquish our rights to our products or technology, and we may not be able to enter into any such contracts or license arrangements on favorable terms, or at all. Our cash position has required us to delay and scale back our development programs and other activities and liquidate certain assets to remain afloat. If we continue to have insufficient funds, particularly if we are unable to undertake any strategic alternative, we may be required to cease our operations altogether.

With the implementation of our Strategic Plan, our primary goal is to successfully complete the review of strategic alternatives and consummate a transaction or series of transactions to seek to realize value for our platform and programs. Our ability to identify and complete such a strategic alternative is highly speculative, and such transactions can be costly to pursue and implement.

Our ability to pursue the research and clinical development activities and other initiatives discussed in the following risk factors and elsewhere in this report will require significant funding, which is unlikely to be available, or may only be pursued if we are able to undertake a strategic alternative.

The Company cautions that trading in the Company’s securities is highly speculative and poses substantial risks. Trading prices for the Company’s securities may bear little or no relationship to the actual value realized, if any, by holders of the Company’s securities. Accordingly, the Company urges extreme caution with respect to existing and future investments in its securities.

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We have significantly reduced our employee base and operations.

In September 2022, we announced a corporate restructuring that will result in a 75% reduction in workforce and refocused the Company's efforts on preclinical research and platform development. In November 2022, we announced the Strategic Plan, significantly reducing our operations and personnel and shifting our focus to a review of strategic alternatives Following these restructurings, we have only nine full-time employees who are focused on reviewing and, if appropriate, pursuing strategic alternatives. Despite this focus, pursuing any strategic alternatives, which we cannot guarantee will be available on favorable terms or at all, is costly and time consuming. If we are unable to identify and pursue a strategic alternative, we may have to cease operations altogether. Even if we were able to obtain additional financing or consummate a strategic alternative such as a merger or sale of the company, we may be unable to resume the research and development efforts and other potential growth initiatives that were curtailed as a result of our cost-reduction plans, which efforts would be critical to any future growth of our business. Further, if our corporate restructuring is not executed successfully, it could have material adverse effects on the effectiveness of our internal control over financial reporting.

We have incurred net losses in every year since our inception and anticipate that we will continue to incur net losses in the future.

We are a preclinical-stage biopharmaceutical company with a limited operating history. 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 effect or an acceptable safety profile, gain regulatory approval and become commercially viable. 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. As a result, we are not profitable and have incurred losses in each period since our inception in 2013. For the nine months ended September 30, 2022 and 2021, we reported net losses of $159.5 million and $141.5 million, respectively. As of September 30, 2022, we had an accumulated deficit of $836.5 million. Further, our cash resources have been significantly depleted, including because of the $75.7 million used to extinguish our long-term debt and satisfy our obligations under the loan and security agreement with SLR Investment Corp. As noted elsewhere in this report, there is substantial doubt as to our ability to fund our planned operations for the next twelve months and to continue to operate as a going concern, and we have recently announced our Strategic Plan which significantly reduced our operations, which will be focused on pursuing strategic alternatives.

As a result of the Strategic Plan, our current financial resources and currently forecasted operating plan would allow us to operate into the first quarter of 2023. We expect our Strategic Plan will reduce our operating expenses with the goal of allowing us to pursue any viable strategic alternatives. There is no guarantee that this plan will be successful. We may not be able to successfully pursue any strategic alternatives and, even if certain strategic alternatives may be available, we cannot provide any assurance that the strategic alternatives review process will result in any particular alternative, transaction or value.

If we were able to continue our operations long-term, we would expect to continue to incur significant expenses and operating losses for at least the next several years. If we were able to continue our operations long-term, we would expect that our expenses and capital requirements would increase in connection with our ongoing activities, particularly if, and as, we:

•conduct preclinical studies and clinical trials for our potential product candidates and if we continue to experience delays, setbacks or disruptions to our preclinical studies or other operations due to the ongoing COVID-19 pandemic, including from any subsequent outbreak whether or not due to emerging variants thereof;

•further develop our next generation red blood cell platform;

•continue to discover and develop potential product candidates;

•maintain, expand and protect our intellectual property portfolio;

•establish clinical and commercial manufacturing sources, as applicable, and secure supply chain capacity sufficient to provide clinical supply for any product candidates that we may develop and commercial quantities of any product candidates for which we may obtain regulatory approval;

•acquire or in-license product candidates and technologies;

•seek regulatory approvals for any product candidates that successfully complete clinical trials;

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•establish a sales, marketing and distribution infrastructure to commercialize any products for which we may obtain regulatory approval; and

•add scientific, clinical, operational, regulatory, financial and management information systems and personnel, including personnel to support our product development and future commercialization efforts, as well as any additional infrastructure necessary to function as a public company.

To become and remain profitable, we or any potential future collaborator must develop and eventually commercialize products with significant market potential at an adequate profit margin after cost of goods sold and other expenses. This will require us to be successful in a range of challenging activities, including completing preclinical studies and clinical trials, obtaining marketing approval for product candidates, obtaining adequate reimbursement for product candidates, manufacturing, marketing and selling products for which we may obtain marketing approval and satisfying any post-marketing requirements. We may never succeed in any or all of these activities and, even if we do, we may never generate revenue that is significant or large enough to achieve profitability. If we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis. Our failure to become and remain profitable would decrease the value of our company and could impair our ability to raise capital, maintain our research and development efforts, expand our business or continue our operations. A decline in the value of our company also could cause our stockholders to lose all or part of their investment.

Even if we succeed in commercializing one or more product candidates, we will continue to incur substantial research and development and other expenditures to develop and market additional product candidates. 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 will require additional capital to fund our operations and if we fail to obtain necessary financing (which will be challenging if not impossible to obtain), we will not be able to complete the development and commercialization of our product candidates.

Our operations have consumed substantial amounts of cash since inception and our available cash has been substantially depleted in light of our October 2022 repayment under the SLR Loan Agreement. We would have to spend substantial amounts to conduct research and development and preclinical or nonclinical testing and studies and clinical trials, to build a supply chain, to seek regulatory approvals for any product candidates we may develop and to launch and commercialize any products for which we receive regulatory approval, including potentially building our own commercial organization. As of September 30, 2022, we had $103.9 million of cash and cash equivalents, without taking into account our early payment of amounts outstanding under our Loan Agreement with SLR. However, our future capital requirements and the period for which our existing resources will support our operations may vary significantly from what we expect, and we will in any event require additional capital (which is unlikely to be available in light of our financial position) in order to complete preclinical and clinical development of any of our current and future programs, if we are able to pursue such initiatives. Our monthly spending levels will vary based on our pursuit of strategic alternatives.

Future financing is unlikely to be available at all, or in sufficient amounts or on terms acceptable to us. 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 even further. We implemented certain cost reduction actions in April and September 2022, respectively, which were intended to focus our capital on advancing our cancer and autoimmune programs and technology platform. If we are unable to obtain additional funding (which will be challenging given our financial position), we will implement further cost reduction actions that delay, scale back or discontinue some or all of our research and development programs and technology platform activities in order to further extend our forecasted cash runway, or may need to cease operations altogether. These actions could significantly harm our business, prospects, financial condition and results of operations, cause the price of our common stock to decline, or even result in holders of our common stock and other securities suffering a total loss of their investment.

If we were able to raise additional capital, such capital may cause dilution to our existing stockholders or require us to relinquish rights to our technologies or product candidates.

To the extent that we are able to raise additional capital through the sale of common stock or securities convertible into, or exchangeable for, common stock, our stockholders’ ownership interest will be diluted, and the terms may include liquidation or other preferences that adversely affect their rights as a stockholder.

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If we raise additional funds through licensing, marketing or distribution arrangements or other collaborations or strategic alliances with third parties, we may have to relinquish valuable rights to our technologies or product candidates, future revenue streams or research programs or grant licenses on terms unfavorable to us. We also could be required to seek collaborators for one or more of our future product candidates at an earlier stage than otherwise would be desirable.

We have an effective shelf registration statement on Form S-3 on file with the Securities and Exchange Commission, or the SEC, pursuant to which we may, from time to time, sell up to an aggregate of $250.0 million (as of September 30, 2022) of our common stock, preferred stock, debt securities, warrants or units. Future sales of securities under the registration statement (or otherwise) would result in dilution of our stockholders and could have a negative impact on our stock price.

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

Our results of operations and general business strategy could be adversely affected by general conditions in the global economy and in the global financial markets. In the past several years, global credit and financial markets have experienced volatility, instability and disruptions, including as a result of the ongoing COVID-19 pandemic. From time to time, this volatility, instability and disruption has caused, and may cause in the future, severely diminished liquidity and credit availability, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. For example, since early 2020, the coronavirus, or COVID-19, pandemic has caused disruption in the financial markets both globally and in the United States. While certain negative effects of the ongoing COVID-19 pandemic have lessened as vaccines are distributed and administered and prevention and treatment methods improve, there have been and may continue to be resurgences of cases, including as a result of the emergence of variants that may be more contagious or more resistant to the vaccine and treatment options available, placing renewed and prolonged strain on both health care facilities and our workforce. Given the inter-connectivity of the global economy, pandemic disease and health events have the potential to continue to negatively impact economic activities in many countries, including the United States. The ongoing spread of the coronavirus, including variants thereof and resurgences in geographies experiencing some relief, could have a negative material impact on our business, prospects, financial condition and results of operations of the Company.

In addition, our general business strategy may be adversely affected by any such economic downturn, volatile business environment or continued unpredictable and unstable market conditions. If the current equity and credit markets deteriorate, or do not improve, 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, scale back or abandon the development or commercialization of one or more of our future product candidates or one or more of our other research and development initiatives. In addition, there is a risk that one or more of our current service providers, manufacturers or other partners may not survive these difficult economic times, which could directly affect our ability to attain our operating goals on schedule and on budget.

Geopolitical developments, such as the Russian invasion of Ukraine or deterioration in the bilateral relationship between the United States and China, may impact government spending, international trade and market stability, and cause weaker macro-economic conditions. The impact of these developments, including any resulting sanctions, export controls or other restrictive actions that may be imposed against governmental or other entities in, for example, Russia, have in the past contributed and may in the future contribute to disruption, instability and volatility in the global markets, which in turn could adversely impact our operations and weaken our financial results. Russia’s invasion of Ukraine, which has persisted for months, and the global response, including the imposition of sanctions by the United States and other countries, could create or exacerbate risks facing our business. The continuing conflict has had a significant impact on the global supply chain, impeding the flow of goods and fueling dramatic cost increases and product shortages, which could adversely affect our supply chain as well. Further, state-sponsored cyberattacks could expand as part of the conflict, which could adversely affect our and our suppliers’ ability to maintain or enhance key cyber security and data protection measures.

Certain political developments may also lead to uncertainty to regulations and rules that may materially affect our business. For example, Brexit could result in the United Kingdom or the European Union significantly altering its regulations affecting the clearance or approval of any product candidates that may in the future be developed in the United Kingdom. Any new regulations could add time and expense to the conduct of our business, as well as the process by which any future product candidates receive regulatory approval, if any, in the United Kingdom, the European Union and elsewhere.

As of September 30, 2022, we had cash and cash equivalents of $103.9 million, without taking into account the early payoff of our SLR Loan Agreement. While we are not aware of any downgrades, material losses, or other significant deterioration in the fair value of our cash equivalents since September 30, 2022, no assurance can be given that further deterioration of the global credit and financial markets would not negatively impact our current portfolio of cash

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equivalents or our ability to meet our financing objectives, and our stock price is likely to suffer as a result of our overall financial condition. Furthermore, our stock price may decline due in part to the volatility of the stock market and the general economic downturn.

Recent increases in interest rates may increase our borrowing costs.

To meet our liquidity needs, we have relied in part on borrowed funds, and may continue to do so in the future, if available. Continued increases in interest rates may increase the cost of any indebtedness we may incur in the future, and could materially and adversely affect our results of operations, financial condition, liquidity and cash flows.

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 our business. In recent years, many such changes have been made and changes are likely to continue to occur in the future. Future changes in tax laws could have a material adverse effect on our business, cash flow, financial condition or results of operations. We urge investors to consult with their legal and tax advisers regarding the implications of potential changes in tax laws on an investment in our common stock.

The amount of and our ability to use net operating losses and research and development credits to offset future taxable income may be subject to certain limitations and uncertainty.

As of December 31, 2021, we had federal and state net operating loss, or NOL, carryforwards of $534.2 million and $534.8 million, respectively, which may be available to offset future taxable income. The federal NOLs include $37.2 million which expire at various dates through 2037 and $497.0 million which carryforward indefinitely. The state NOLs expire at various dates through 2041. As of December 31, 2021, we also had federal and state research and development tax credit carryforwards of $22.7 million and $15.6 million, respectively, which may be available to offset future tax liabilities and begin to expire in 2034 and 2026, respectively.

Federal NOLs generated in taxable years after December 31, 2017 generally may not be carried back to prior taxable years, and while such federal NOLs generated in taxable years beginning after December 31, 2017 will not be subject to expiration, the deduction for such NOL in any taxable year will be limited to 80% of our taxable income in such year, where taxable income is determined without regard to the NOL deduction itself. However, the Coronavirus Aid, Relief and Economic Security Act repeals the 80% limitation on the utilization of such federal NOLs generated in taxable years beginning after December 31, 2017 and beginning before January 1, 2021 and allows for federal NOLs generated in taxable years beginning after December 31, 2017 and before January 1, 2021, to be carried back to each of the five taxable years preceding the taxable year in which the loss arises. It is uncertain whether this change in law temporarily allowing for the carryback of federal NOLs will produce any material benefit for our business.

In addition, in general, under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, or the Code, a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change NOLs or tax credits, or NOLs or credits (including federal research and development tax 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. Our existing NOLs or credits may be subject to limitations arising from previous ownership changes, including in connection with our earlier private placements, IPO, our March 2021 underwritten offering and other transactions. In addition, future changes in our stock ownership, many of which are outside of our control, could result in an ownership change under Sections 382 and 383 of the Code and limit our ability to utilize our NOLs and our credits. Our NOLs or credits may also be impaired under state law. Accordingly, 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. As described above under this section captioned “Risk factors—Risks related to our financial condition and capital requirements,” 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 that are subject to limitation by Sections 382 and 383 of the Code.

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Risks related to future performance

We have a limited operating history, which may make it difficult to evaluate our technology and product development capabilities and predict our future performance.

We were formed in 2013, have no products approved for commercial sale and have not generated any revenue from product sales. We are early in our development efforts for our oncology and autoimmune programs, each of which will require additional preclinical research and development, clinical development, regulatory approval in multiple jurisdictions, obtaining manufacturing supply, capacity and expertise, building of a commercial organization, substantial investment and significant marketing efforts before we generate any revenue from product sales. In addition, any product candidates we may develop must be approved for marketing by the FDA or certain other health regulatory agencies, such as the EMA, before we may commercialize any product. Our ability to generate product revenue or profits, which we do not expect will occur for many years, if ever, will depend on the successful development and eventual commercialization of product candidates, which may never occur.

Our limited operating history, particularly in light of the rapidly evolving cellular therapeutics field, may make it difficult to evaluate our technology and industry and predict our future performance. Our short history as an operating company makes any assessment of our future success or viability subject to significant uncertainty. We will encounter risks and difficulties frequently experienced by early-stage companies in rapidly evolving fields. If we do not address these risks successfully, our business will suffer. Similarly, we expect that our financial condition and operating results will fluctuate significantly from quarter to quarter and year to year due to a variety of factors, many of which are beyond our control. As a result, our shareholders should not rely upon the results of any quarterly or annual period as an indicator of future operating performance.

In addition, as an early-stage company, we have encountered unforeseen expenses, difficulties, complications, delays and other known and unknown circumstances, including, for example, the manufacturing and enrollment challenges we faced in connection with our Phase 1b clinical trial for RTX-134, which we discontinued in March 2020, and the clinical development challenges we faced in connection with our Phase 1 trials for RTX-224 and RTX-240, which we discontinued in September 2022, and RTX-321, which we discontinued in May 2022.

With the implementation of our Strategic Plan, our primary goal is to successfully complete the review of strategic alternatives and consummate a transaction or series of transactions to seek to realize value for our platform and programs. Our ability to identify and complete such a strategic alternative is highly speculative, and such transactions can be costly to pursue and implement.

Our ability to pursue the research and clinical development activities and other initiatives discussed in our risk factors and elsewhere in this report will require significant funding, which is unlikely to be available, or may only be pursued if we are able to undertake a strategic alternative.

The Company cautions that trading in the Company’s securities is highly speculative and poses substantial risks. Trading prices for the Company’s securities may bear little or no relationship to the actual value realized, if any, by holders of the Company’s securities. Accordingly, the Company urges extreme caution with respect to existing and future investments in its securities.

Our business is highly dependent on the success of our preclinical programs targeting cancer and autoimmune diseases. Any of our product candidates that we may develop will require significant additional nonclinical, preclinical and clinical development before we can seek regulatory approval for and launch a product commercially.

Our business and future success depends on our ability to obtain regulatory approval of and then successfully launch and commercialize product candidates targeting cancer and autoimmune diseases that may be selected from our preclinical programs. If we were to continue or resume such activities, we may experience delays or setbacks in advancing any such product candidates, including the inability to generate sufficient preclinical, toxicology, or other in vivo or in vitro data to support the initiation of clinical trials and complications surrounding trial execution, such as complexities surrounding trial design, establishing trial protocols and interpretability of results, clinical site access and initiation, patient recruitment and enrollment, quality and supply of clinical doses, safety issues, or a lack of clinically relevant activity. For example, we encountered manufacturing and enrollment challenges in connection with our Phase 1b clinical trial for our discontinued product candidate, RTX-134, and clinical development challenges with our Phase 1 clinical trials for our discontinued product candidates RTX-224, RTX-240 and RTX-321.

All of our pipeline products are in the early stages of development and will require additional nonclinical and preclinical development, clinical development, regulatory review and approval in multiple jurisdictions, substantial investment, access

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to sufficient commercial manufacturing capacity and significant marketing efforts before we can generate any revenue from product sales. If any product candidates we may develop encounter safety, efficacy, supply or manufacturing problems, developmental or unexpected delays, regulatory or commercialization issues or other problems, our development plans and business would be significantly harmed.

The successful development of cellular therapeutics, such as our Red Cell Therapeutics, is highly uncertain.

Successful development of cellular therapeutics, such as the RCTs that we have been developing, is highly uncertain and is dependent on numerous factors, many of which are beyond our control. Cellular therapeutics that appear promising in the early phases of development may fail to reach the market for several reasons, including:

•nonclinical or preclinical testing or study results may show our RCTs to be less effective than desired or to have harmful or problematic side effects or toxicities;

•clinical trial results may show our RCTs to be less effective than expected (e.g., a clinical trial could fail to meet its primary endpoint(s)) or to have unacceptable side effects or toxicities;

•clinical trial results may show that our RCTs may not have the circulating time we expect based on preclinical studies and models, which may negatively affect the activity observed in clinical trials;

•failure to receive the necessary regulatory approvals or a delay in receiving such approvals. Among other things, such delays may be caused by slow enrollment in clinical trials, manufacturing delays, patients dropping out of trials, length of time to achieve trial endpoints, additional time requirements for data analysis, or biologics license application, or BLA, preparation, discussions with the FDA, an FDA request for additional nonclinical or clinical data, including bridging studies, or unexpected safety or manufacturing issues;

•manufacturing issues and costs, formulation issues, dosage requirements, pricing or reimbursement issues, or other factors that make our RCT therapies uneconomical; and

•proprietary rights of others and their competing products and technologies that may prevent our RCT therapies from being commercialized.

The length of time necessary to complete clinical trials and to submit an application for marketing approval for a final decision by a regulatory authority may be difficult to predict for cellular therapies, in large part because of the limited regulatory history.

Even if we are successful in obtaining market approval, commercial success of any approved products will also depend in large part on the availability of insurance coverage and adequate reimbursement from third-party payors, including government payors, such as the Medicare and Medicaid programs, and managed care organizations, which may be affected by existing and future healthcare reform measures designed to reduce the cost of healthcare. Even if coverage is provided, the approved reimbursement amount may not be high enough to allow us to establish or maintain pricing sufficient to realize a sufficient return on our investment. Government authorities and third-party payors may decide which medications to pay for and establish their own reimbursement levels, limit the definition of the target treatment population to one smaller than that implied in the label granted by regulatory authorities, and could require us to conduct additional studies, including post-marketing studies related to the cost-effectiveness of a product, to qualify for reimbursement, which could be costly and divert our resources. If government and other healthcare payors were not to provide adequate insurance coverage and reimbursement levels for one any of our products once approved, market acceptance and commercial success would be reduced.

In addition, if any of our future product candidates are approved for marketing, we will be subject to significant regulatory obligations regarding the submission of safety and other post-marketing information and reports and registration and will need to comply (or ensure that our third-party providers comply) with current good manufacturing practices, or cGMPs, for the commercial supply of such product, and good clinical practices, or GCPs, for any clinical trials that we conduct post-approval. In addition, there is always the risk that we or a regulatory authority might identify previously unknown problems with a product post-approval, such as adverse events of unanticipated severity or frequency. Compliance with these requirements is costly and any failure to comply or other issues with our product candidates post-approval could have a material adverse effect on our business, financial condition and results of operations.

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Our future product candidates are based on a new technology, which makes it difficult to predict the time and cost of development and of subsequently obtaining regulatory approval, if at all.

Our red blood cell technology is relatively new and no products that use red blood cell-based cell conjugation technology have been approved to date in the United States, the United Kingdom, or the European Union. As such, it is difficult to accurately predict the challenges we may experience with any of our future product candidates as they proceed through product discovery or identification, preclinical studies and clinical trials.

In addition, because we have not completed any clinical trials, we have not yet been able to meaningfully assess safety of our red blood cell technology in humans, and there may be short-term or long-term effects from treatment with any product candidates that we may develop that we cannot predict at this time. Further, animal models may not exist for some of the diseases we choose to pursue in our programs. Cellular therapies, such as the potential product candidates we have been developing, have a limited circulating time in animals as they are recognized as foreign by the host animal and therefore cleared by the complement-mediated reticuloendothelial system, which limits the safety and toxicology assessments that we can conduct in preclinical studies.

As a result of these factors, it is more difficult for us to predict the time and cost of product candidate development, and we cannot predict whether the application of our next generation red blood cell platform, or any similar or competitive cellular technologies, will result in the successful identification, development, and regulatory approval of any product candidates. Any development problems we experience in the future related to our red blood cell platform or any of our research programs could cause significant delays or unanticipated costs and may be challenging or impossible to resolve. Any of these factors may prevent us from completing our preclinical studies or any clinical trials that we may initiate or commercializing any product candidates we may develop on a timely or profitable basis, if at all.

The clinical trial requirements of the FDA, the EMA and other 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 product candidate. Because no product that uses red blood-cell based cell conjugation technology has been approved to date by regulators, the regulatory approval process and timeline for product candidates such as our future product candidates are uncertain and may be more expensive and take longer than the approval process and timeline for product candidates based on other, better known or more extensively studied technologies. It is difficult to determine how long it will take or how much it will cost to obtain regulatory approvals for any product candidates we may develop in either the United States or the European Union or other regions of the world or how long it will take to commercialize any such product candidates. Delay or failure to obtain, or unexpected costs in obtaining, the regulatory approval necessary to bring a potential product candidate to market could result in increased costs and decrease our ability to generate sufficient product revenue, and our business, financial condition, results of operations and prospects may be harmed.

Our operating results may fluctuate significantly, which makes our future operating results difficult to predict and could cause our operating results to fall below expectations or our guidance.

Our quarterly and annual operating results may fluctuate significantly in the future, which makes it difficult for us to predict our future operating results. From time to time, we may enter into license or collaboration agreements with other companies that include development funding and significant upfront and milestone payments and/or royalties, which may become an important source of our revenue. Accordingly, our revenue may depend on development funding and the achievement of development and clinical milestones under any potential future license and collaboration agreements and sales of our products, if approved. These upfront and milestone payments may vary significantly from period to period and any such variance could cause a significant fluctuation in our operating results from one period to the next.

In addition, we measure compensation cost for stock-based awards made to employees, directors and non-employee consultants based on the fair value of the award on either the grant date or service completion date, and we recognize the cost as an expense over the recipient’s service period. Because the variables that we use as a basis for valuing stock-based awards change over time, including our underlying stock price and stock price volatility, the magnitude of the expense that we must recognize may vary significantly.

Furthermore, our operating results may fluctuate due to a variety of other factors, many of which are outside of our control and may be difficult to predict, including, if we were to continue or resume research and development activities, the following:

•the timing and cost of, and level of investment in, research and development activities relating to our pipeline products and any future product candidates, which will change from time to time;

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•our ability to enroll patients in any future clinical trials and the timing of enrollment;

•the cost of manufacturing any future product candidates, which may vary depending on FDA guidelines and requirements, the quantity of production and the terms of our agreements with any third-party manufacturers we may engage;

•expenditures that we may incur to acquire or develop product candidates and technologies;

•the timing and outcomes of preclinical studies and clinical trials for any product candidates we may develop or competing product candidates;

•competition from existing and potential future products that compete with any product candidates we may develop, and changes in the competitive landscape of our industry, including consolidation among our competitors or partners;

•any delays in regulatory review or approval of any product candidates we may develop;

•the level of demand for any future product candidates for which we obtain regulatory approval, which may fluctuate significantly and be difficult to predict;

•the risk/benefit profile, cost and reimbursement policies with respect to any future product candidates for which we obtain regulatory approval, and existing and potential future products that compete with any product candidates we may develop;

•our ability to commercialize any future product candidates for which we obtain regulatory approval, inside and outside of the United States, either independently or working with third parties;

•our ability to adequately support future growth;

•potential unforeseen business disruptions that increase our costs or expenses;

•future accounting pronouncements or changes in our accounting policies; and

•the changing and volatile global economic environment.

The cumulative effect of these factors could result in large fluctuations and unpredictability in our quarterly and annual operating results. As a result, comparing our operating results on a period-to-period basis may not be meaningful. Investors should not rely on our past results as an indication of our future performance. This variability and unpredictability could also result in our failing to meet the expectations of industry or financial analysts or investors for any period. If our revenue or operating results fall below the expectations of analysts or investors or below any forecasts we may provide to the market, or if the forecasts we provide to the market are below the expectations of analysts or investors, the price of our common stock could decline substantially. Such a stock price decline could occur even when we have met any previously publicly stated revenue and/or earnings guidance we may provide.

Risks related to product development and clinical trials

The FDA, the EMA and other regulatory authorities may implement additional regulations or restrictions on the development and commercialization of our product candidates, which may be difficult to predict.

The FDA, the EMA and regulatory authorities in other countries have each expressed interest in further regulating biotechnology products, such as cellular therapies. Agencies at both the federal and state level in the United States, as well as the U.S. Congressional committees and other governments or governing agencies, have also expressed interest in further regulating the biotechnology industry. Such action may delay or prevent commercialization of some or all of the product candidates we may develop. Adverse developments in clinical trials of cellular therapy products conducted by others may cause the FDA or other oversight bodies to change the requirements for approval of any of our future product candidates. Similarly, the EMA governs the development of cellular therapies in the European Union and may issue new guidelines concerning the development and marketing authorization for cellular therapy products and require that we comply with these new guidelines. These and other regulatory review agencies and committees and the new requirements or guidelines they promulgate may lengthen the regulatory review process, require us to perform additional studies or trials, increase our development costs, lead to changes in regulatory positions and interpretations, delay or prevent approval and commercialization of any product candidates we may develop or lead to significant post-approval limitations or restrictions. As we advance our potential product candidates, we will be required to consult with these regulatory agencies

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and comply with applicable requirements and guidelines. If we fail to do so, we may be required to delay or discontinue development of such product candidates. These additional processes may result in a review and approval process that is longer than we otherwise would have expected. Regulatory authorities in different jurisdictions do not always agree on required nonclinical or clinical data or other requirements for product development and approval and may provide contradictory guidance, thus potentially further complicating or delaying product development or approval. Additionally, any delays in the regulatory approval process resulting from the ongoing COVID-19 pandemic could increase our costs and negatively impact our ability to initiate or complete clinical trials and commercialize any future product candidates in a timely manner, if at all.

Clinical development involves a lengthy and expensive process, with an uncertain outcome. We may incur additional costs or experience delays in completing, or ultimately be unable to complete, the development and commercialization of any product candidates.

To obtain the requisite regulatory approvals to commercialize any product candidates, we must demonstrate through extensive preclinical studies and clinical trials that such product candidates are safe and effective in humans. Clinical testing is expensive, difficult to design and implement and can take many years to complete, and its outcome is inherently uncertain. We may be unable to establish clinical endpoints that applicable regulatory authorities would consider clinically meaningful, and a clinical trial can fail at any stage of testing. The outcome of nonclinical studies and early clinical trials may not be predictive of the success of later clinical trials, and interim results of a clinical trial do not necessarily predict final results. Differences in trial design between early-stage clinical trials and later-stage clinical trials make it difficult to extrapolate the results of earlier clinical trials to later clinical trials. Moreover, nonclinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that have believed their product candidates performed satisfactorily in nonclinical studies and clinical trials have nonetheless failed to obtain marketing approval of their products.

Successful completion of clinical trials is a prerequisite to submitting a BLA to the FDA, a marketing authorization application, or MAA, to the EMA, and similar marketing applications to comparable foreign regulatory authorities, for each product candidate and, consequently, the ultimate approval and commercial marketing of any product candidates. We do not know whether we will be able to commence any future clinical trials, or, if commenced, whether any such clinical trials will be completed on schedule, if at all.

In addition, certain of our product candidate development programs may contemplate the development of companion diagnostics, which are assays or tests to identify an appropriate patient population. Companion diagnostics are subject to regulation as medical devices and must themselves be cleared or approved for marketing by the FDA or certain other foreign regulatory agencies before we may commercialize any such product candidates, if approved. We may experience numerous unforeseen events that could delay or prevent our ability to initiate, resume or complete our preclinical or nonclinical testing and studies or clinical trials, receive marketing approval or launch and commercialize any product candidates we may develop, including:

•we may be unable to generate sufficient preclinical, toxicology, or other in vivo or in vitro data to support the initiation of clinical trials;

•regulators or institutional review boards, or IRBs, or ethics committees may not authorize us or our investigators to commence a clinical trial or conduct a clinical trial at a prospective trial site;

•we may experience delays in reaching, or fail to reach, agreement on acceptable terms with prospective trial sites and prospective contract research organizations, or CROs, the terms of which can be subject to extensive negotiation and may vary significantly among different CROs and trial sites;

•clinical trials of any product candidates we may develop may fail to show safety, purity or potency, or produce negative or inconclusive results and we may decide, or regulators may require us, to conduct additional nonclinical studies or clinical trials, such as bridging studies, or revise our trial design or testing protocols, which could adversely affect the approvability and commercial viability of such product candidates, or we may decide to abandon product development programs as we did with RTX-321, RTX-240 and RTX-224;

•the number of patients required for clinical trials of any product candidates we may develop may be larger than we anticipate, enrollment in these clinical trials may be slower than we anticipate, as was the case in our Phase 1b trial for our discontinued product candidate, RTX-134, or participants may drop out of these clinical trials or fail to return for post-treatment follow-up at a higher rate than we anticipate, and patient enrollment and participation may continue to be affected by the ongoing COVID-19 pandemic;

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•we may need to add new or additional clinical trial sites;

•we may not be successful in developing, clearing or obtaining approval of companion diagnostics for use with certain of our future product candidates;

•our third-party contractors may fail to comply with regulatory requirements or meet their contractual obligations to us in a timely manner, or at all, or may deviate from the clinical trial protocol or drop out of the trial, which may require that we add new clinical trial sites or investigators;

•the cost of preclinical or nonclinical testing and studies and clinical trials of any product candidates may be greater than we anticipate or greater than our available financial resources;

•the supply or quality of any product candidates we may develop or other materials necessary to conduct clinical trials of any product candidates we may develop, including raw materials, may be untimely, insufficient or inadequate and we or our suppliers, contract manufacturing organizations, or CMOs, and CROs may experience interruptions or delays, including on account of man-made or natural disasters, medical epidemics or pandemics, including the ongoing COVID-19 pandemic, shortages in the donor blood supply chain, and the U.S. government’s utilization of its Defense Production Act authority and the resulting impact on the biologic supply chain;

•RCTs may circulate longer or shorter in humans than anticipated;

•we may not be able to successfully enforce and defend our intellectual property rights and claims;

•any product candidates we may develop may have undesirable side effects or other unexpected characteristics, causing us or our investigators, regulators or IRBs or ethics committees to suspend or terminate the trials, or reports may arise from preclinical or clinical testing of other therapies for cancer and autoimmune diseases or additional diseases that we target that raise safety or efficacy concerns about our product candidates;

•unforeseen global instability, including political instability or instability from an outbreak of pandemic or contagious disease, such as COVID-19 and variants thereof, in or around the cities and countries in which we conduct our clinical trials or where our third-party contractors operate; and

•the FDA or other regulatory authorities may require us to submit additional data, such as long-term toxicology studies, or impose other requirements before permitting us to initiate a clinical trial and, as seen with gene therapies, could impose long-term safety follow-up for any of our clinical trials.

We could also encounter delays if a clinical trial is suspended or terminated by us, the IRBs of the institutions in which such trials are being conducted, or the FDA or other regulatory authorities, or recommended for suspension or termination by the Data Safety Monitoring Board, or DSMB, for such trial. A suspension or termination 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 other 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 product or treatment, failure to establish or achieve clinically meaningful trial endpoints, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. Many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of a given product candidate. Further, the FDA or other regulatory authorities may disagree with our clinical trial design and our interpretation of data from clinical trials or may change the requirements for approval even after they have reviewed and commented on the design for our clinical trials.

Additionally, if we conduct any clinical trials in the future, they may be open label in study design and may be conducted at a limited number of clinical sites on a limited number of patients. An “open-label” clinical trial is one where both the patient and investigator know whether the patient is receiving the investigational product candidate or either an existing approved drug or placebo. 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. Moreover, patients selected for early clinical studies often include the most severe sufferers and their symptoms may have been bound to improve notwithstanding the new 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.

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Our product development costs will increase if we experience delays in clinical testing or marketing approvals. We do not know whether any of our preclinical or nonclinical testing and studies or clinical trials will begin as planned, will need to be restructured or will be completed on schedule, or at all. Significant preclinical or nonclinical testing and studies or clinical trial delays also could shorten any periods during which we may have the exclusive right to commercialize any product candidates we may develop and may allow our competitors to bring products to market before we do, potentially impairing our ability to successfully commercialize such product candidates and harming our business and results of operations. Any delays in our nonclinical or future clinical development programs may harm our business, financial condition and prospects significantly.

Preclinical development is uncertain. Our preclinical programs may experience delays or may never advance to clinical trials, which would adversely affect our ability to obtain regulatory approvals or commercialize these programs on a timely basis or at all, which would have an adverse effect on our business.

All of our potential product candidates are still in the preclinical stage, and their risk of failure is high. Before we can commence clinical trials for a product candidate, we must complete extensive preclinical testing and studies that support our planned INDs in the United States, or similar applications in other jurisdictions. We cannot be certain of the timely completion or outcome of our preclinical testing and studies and cannot predict if the FDA or other regulatory authorities will accept our proposed clinical programs or if the outcome of our preclinical testing and studies will ultimately support the further development of our programs. As a result, we cannot be sure that we will be able to submit INDs or similar applications, or subsequent protocol amendments, for our preclinical programs on the timelines we expect, if at all, and we cannot be sure that submission of INDs or similar applications will result in the FDA or other regulatory authorities allowing testing and clinical trials to begin or proceed, or that, once begun, issues will not arise that lead to the suspension or termination of such clinical trials. Additionally, even if such regulatory authorities agree with the design and implementation of the clinical trials set forth in an IND or similar application, we cannot guarantee that such regulatory authorities will not change their requirements in the future.

The clinical trials we conduct or those of our future collaborators may reveal significant adverse events not seen in our preclinical or nonclinical studies and may result in a safety profile that could inhibit regulatory approval or market acceptance of any of our future product candidates.

Before obtaining regulatory approvals for the commercial sale of any of our future product candidates, we must demonstrate through lengthy, complex and expensive preclinical studies and clinical trials that such product candidates are both safe and effective for use in each target indication. Clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Failure can occur at any time during the clinical trial process. The results of preclinical studies and early clinical trials of any product candidates we may develop may not be predictive of the results of later-stage clinical trials. In addition, initial success in clinical trials may not be indicative of results obtained when such trials are completed. There is typically an extremely high rate of attrition from the failure of product candidates proceeding through clinical trials. As is the case with many treatments for cancer and autoimmune diseases, it is likely that there may be side effects associated with their use. For example, the RCTs we have been developing are produced from O negative donor red blood cells and we believe can therefore be used as allogeneic therapies in approximately 95% of patients. However, following repeated dosing, some patients may develop antibodies to blood antigens on our RCTs. These antibodies could reduce the efficacy of our RCTs or result in undesirable side effects.

Product candidates in later stages of clinical trials also may fail to show the desired safety and efficacy profile despite having progressed through nonclinical and preclinical studies and earlier clinical trials. A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to lack of efficacy or unacceptable safety issues, notwithstanding promising results in earlier trials. Most product candidates that commence clinical trials are never approved as products and there can be no assurance that any of our future clinical trials will ultimately be successful or support further clinical development of any of our future product candidates.

We may develop future product candidates in combination with one or more therapies. The uncertainty resulting from the use of any such product candidates in combination with such other therapies may make it difficult to accurately predict side effects in future clinical trials.

Results of any clinical trials we may conduct could reveal a high and unacceptable severity and prevalence of these or other side effects. Further, if significant adverse events or other side effects are observed in any of the clinical trials we may conduct, including the discontinued clinical trials for RTX-240, RTX-224, and RTX-321, we may have difficulty recruiting patients to our clinical trials, patients may drop out of our trials, or the FDA or comparable foreign regulatory authorities could order us to cease further development of or deny approval of our product candidates for any or all targeted indications, or interrupt, delay or halt the trials or our development efforts of one or more product candidates. We, the FDA or other applicable regulatory authorities, or an IRB may suspend clinical trials of a product candidate at any time for

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various reasons, including a belief that subjects in such trials are being exposed to unacceptable health risks or adverse side effects. Some potential therapeutics developed in the biotechnology industry that initially showed therapeutic promise in early-stage trials have later been found to cause side effects that prevented their further development. Even if the side effects do not preclude the drug from obtaining or maintaining marketing approval, undesirable side effects may cause delays in such approval, result in a more restrictive label or inhibit market acceptance of the approved product due to its tolerability or label versus other therapies.

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 given product candidate may only be uncovered with a significantly larger number of patients exposed to such product candidate. If any of our future product candidates receive marketing approval and we or others identify undesirable side effects caused by such product candidates (or any other similar drugs) after such approval, a number of potentially significant negative consequences could result, including that regulatory authorities may withdraw or limit their approval of such product candidates, we may be subject to regulatory investigations and government enforcement actions, we may be required to change the way such product candidates are distributed or administered, conduct additional clinical trials or change the labeling of the product candidates and our reputation may suffer.

We believe that any of these events or developments could prevent us from achieving or maintaining market acceptance of the affected product candidates and could materially harm our business, financial condition and prospects.

If we encounter difficulties enrolling patients in any clinical trials we may conduct in the future, our clinical development activities could be delayed or otherwise adversely affected.

We may experience difficulties in patient enrollment in any future clinical trials we may conduct for a variety of reasons. The timely completion of clinical trials in accordance with their protocols depends, among other things, on the ability to enroll a sufficient number of patients who remain in the study until its conclusion. The enrollment of patients depends on many factors, including:

•the severity of the disease under investigation;

•the patient eligibility and exclusion criteria defined in the protocol;

•clinical development programs in the same patient population, resulting in competition for clinical trial enrollment;

•the size of the patient population required for analysis of the trial’s primary endpoints;

•the proximity of patients to trial sites, and the ability or willingness of patients to travel to trial sites during the ongoing COVID-19 pandemic;

•the design of the trial;

•impacts of the ongoing COVID-19 pandemic on clinical trial site activation;

•the ability to recruit clinical trial investigators and other personnel with the appropriate competencies and experience, and the availability of qualified investigators and other personnel to conduct clinical trials during the ongoing COVID-19 pandemic;

•clinicians’ and patients’ perceptions as to the potential advantages and risks of the product candidate being studied in relation to other available therapies, including any new drugs that may be in clinical development or approved for the indications we are investigating;

•the efforts to facilitate timely enrollment in clinical trials;

•the patient referral practices of physicians;

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

•the availability of adequate supply or quality of the product candidates or other materials necessary to conduct clinical trials, including as a result of the ongoing COVID-19 pandemic;

•the ability to obtain and maintain patient consents; and

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

Any clinical trials we may conduct in the future will compete with other clinical trials of product candidates that are in the same therapeutic areas as our future product candidates, and this competition will reduce the number and types of patients available to us, because some patients who might have opted to enroll in our trials may instead opt to enroll in a trial being conducted by one of our competitors. Additionally, since the number of qualified clinical investigators is limited, we expect to conduct some of our future clinical trials at the same clinical trial sites that some of our competitors use, which may reduce the number of investigators who are available for our clinical trials in such clinical trial sites. Moreover, because our future product candidates will represent a departure from more commonly used methods for our targeted therapeutic areas, potential patients and their doctors may be inclined to use conventional or newly launched competitive therapies, rather than enroll patients in any future clinical trial. For example, we experienced patient enrollment challenges in our Phase 1 clinical trial of RTX-321, which was discontinued in May 2022, likely as a result of competition for patient enrollment, alongside the impacts of the ongoing COVID-19 pandemic on staffing and site activation in general.

Delays in patient enrollment may result in increased costs or may affect the timing or outcome of any future clinical trials we may conduct, which could prevent completion of these trials and adversely affect our ability to advance the development of our future product candidates.

Interim, top-line and preliminary data from preclinical studies and future clinical trials that we announce or publish from time to time may change as more preclinical and 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 publish interim, top-line or preliminary data from our preclinical studies and clinical trials, which are based on a preliminary analysis of then-available data. Interim, preliminary or top-line data from any clinical trials that we may complete 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. 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. As a result, the topline 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 and preliminary data should be viewed with caution until the final data are available. Adverse differences between preliminary or interim data and final data could significantly harm our business prospects. Further, disclosure of interim data by us or by our competitors could result in volatility in the price of our common stock.

Positive results from early preclinical studies or early clinical trials are not necessarily predictive of the results of later preclinical studies or later clinical trials. If we cannot replicate the positive results from our earlier preclinical studies or earlier clinical trials in our later preclinical studies or later clinical trials, we may be unable to successfully develop, obtain regulatory approval for and commercialize our product candidates.

Any positive results from our preclinical studies or early clinical trials may not necessarily be predictive of the results from later preclinical studies or later clinical trials. Similarly, even if we are able to complete our ongoing or planned preclinical studies or future clinical trials according to our development timelines, the positive results from such preclinical studies or clinical trials may not be replicated in subsequent preclinical studies or clinical trial results.

Many companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in late-stage clinical trials after achieving positive results in early-stage development and we cannot be certain that we will not face similar setbacks. These setbacks have been caused by, among other things, preclinical and other nonclinical findings made while clinical trials were underway, or safety or efficacy observations made in preclinical studies and clinical trials, including previously unreported adverse events. Moreover, preclinical, nonclinical and clinical data are often susceptible to varying interpretations and analyses and many companies that believed their product candidates performed satisfactorily in preclinical studies and clinical trials nonetheless failed to obtain FDA or EMA approval.

We may develop future product candidates in combination with other therapies, and safety or supply issues with combination-use products may delay or prevent development and approval of any such product candidates.

We may develop future product candidates in combination with one or more therapies, both approved and unapproved. Even if any product candidate we may develop were to receive marketing approval or be commercialized for use in combination with other existing therapies, we would continue to be subject to the risks that the FDA or similar regulatory

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authorities outside of the United States could revoke approval of the therapy used in combination with such product candidate or that safety, efficacy, manufacturing or supply issues could arise with these existing therapies. Combination therapies are commonly used for the treatment of cancer, and we would be subject to similar risks if we develop any of our product candidates for use in combination with other drugs for indications other than cancer. Similarly, if the therapies we use in combination with any of our future product candidates are replaced as the standard of care for the indications we choose for such product candidates, the FDA or similar regulatory authorities outside of the United States may require us to conduct additional clinical trials. The occurrence of any of these risks could result in our own products, if approved, being removed from the market or being less successful commercially.

We may also evaluate future product candidates in combination with one or more therapies that have not yet been approved for marketing by the FDA or similar regulatory authorities outside of the United States. We will not be able to market and sell any product candidate we may develop in combination with any such unapproved therapies if such therapies do not ultimately obtain marketing approval. The regulations prohibiting the promotion of products for unapproved uses are complex and subject to substantial interpretation by the FDA and other government agencies. In addition, there are additional risks that result from the fact that such therapies are unapproved, such as the potential for serious adverse effects and delay in their clinical trials.

If the FDA or similar regulatory authorities outside of the United States do not approve these other drugs or revoke their approval, or if safety, efficacy, manufacturing, or supply issues arise with the drugs we choose to evaluate in combination with any product candidate we may develop, we may be unable to obtain approval of or market such product candidate.

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

Because we have limited financial and managerial resources, we intend to focus on developing product candidates for specific indications that we identify as most likely to succeed, in terms of both their potential for regulatory approval and commercialization. As a result, we may forego or delay pursuit of opportunities with other product candidates or for other indications that may prove to have greater commercial potential.

Our resource allocation decisions may cause us to fail to capitalize on viable commercial drugs or profitable market opportunities. Our spending on current and future research and development programs and product candidates for specific indications may not yield any commercially viable product candidates. If we do not accurately evaluate the commercial potential or target market for a particular product candidate, we may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to the product candidate.

We may not be successful in our efforts to identify product candidates. Due to our limited resources and access to capital, we must prioritize development of certain product candidates, which may prove to be wrong and may adversely affect our business.

Although we intend to explore other therapeutic opportunities in addition to the pipeline products that we have been developing, we may fail to identify viable product candidates for clinical development for a number of reasons. If we fail to identify potential product candidates, our business could be materially harmed.

Research programs to pursue the development of our planned product candidates for additional indications and to identify new product candidates and disease targets require substantial technical, financial and human resources whether or not they are ultimately successful. Our research programs may initially show promise in identifying potential indications and/or product candidates, yet fail to yield results for clinical development for a number of reasons, including:

•the research methodology used may not be successful in identifying potential indications and/or product candidates;

•potential product candidates may, after further study, be shown to have harmful adverse effects or other characteristics that indicate they are unlikely to be effective drugs; or

•it may take greater human and financial resources than we will possess to identify additional therapeutic opportunities for our product candidates or to develop suitable potential product candidates through internal research programs, thereby limiting our ability to develop, diversify and expand our product portfolio.

Because we have limited financial and human resources, we intend to initially focus on research programs and product candidates for a limited set of indications. As a result, we may forego or delay pursuit of opportunities with other product

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candidates or for other indications that later prove to have greater commercial potential or a greater likelihood of success. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities.

Accordingly, there can be no assurance that we will ever be able to identify additional therapeutic opportunities for any future product candidates or to develop suitable potential product candidates through internal research programs, which could materially adversely affect our future growth and prospects. We may focus our efforts and resources on potential product candidates or other potential programs that ultimately prove to be unsuccessful.

Risks related to sales, marketing and competition

The market opportunities for our product candidates may be limited to those patients who are ineligible for other therapies or who have failed prior treatments and may be small, and our estimates of the prevalence of our target patient populations may be inaccurate.

Cancer and autoimmune therapies are sometimes characterized as first-line, second-line, third-line and even fourth-line, and the FDA often approves new therapies initially only for last-line use. Initial approvals for new cancer and autoimmune therapies are often restricted to later lines of therapy, and in the case of cancer specifically, for patients with advanced or metastatic disease. This will limit the number of patients who may be eligible for such new therapies, which may include our future product candidates.

Our projections of both the number of people who have the diseases we are targeting, as well as the subset of people with these diseases in a position to receive our therapies, if approved, are based on our beliefs and estimates. These estimates have been derived from a variety of sources, including scientific literature, input from key opinion leaders, patient foundations, or secondary market research databases, and may prove to be incorrect. For example, the number of new products in development for the diseases we are targeting continues to grow, and it is conceivable that patients will have multiple treatment options in the future. Further, new studies may change the estimated incidence or prevalence of these diseases. The number of patients may turn out to be lower than expected. Additionally, the potentially addressable patient population for our future product candidates may be limited or may not be amenable to treatment with such product candidates. Furthermore, regulators and payors may further narrow the therapy-accessible treatment population. Even if we obtain significant market share for our future product candidates, because certain of the potential target populations are small, we may never achieve profitability without obtaining regulatory approval for additional indications.

We face significant competition from other biotechnology and pharmaceutical companies, and our operating results will suffer if we fail to compete effectively.

The biopharmaceutical industry is characterized by intense competition and rapid innovation. Our competitors may be able to develop other compounds, drugs, cellular or gene therapies that are able to achieve similar or better results. Our potential competitors include major multinational pharmaceutical companies, established biotechnology companies, specialty pharmaceutical companies and universities and other research institutions. Many of our competitors have substantially greater financial, technical and other resources, such as larger research and development staff, experienced marketing and manufacturing organizations and well-established sales forces. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large, established companies. Established pharmaceutical companies may also invest heavily to accelerate discovery and development of novel therapeutics or to in-license novel therapeutics that could make the product candidates that we may develop obsolete. Mergers and acquisitions in the biotechnology and pharmaceutical industries may result in even more resources being concentrated in our competitors. Competition may increase further as a result of advances in the commercial applicability of technologies and greater availability of capital for investment in these industries. Our competitors, either alone or with collaborative partners, may succeed in developing, acquiring or licensing, on an exclusive basis, drug, biologic, cellular or gene therapy products that are more effective, safer, more easily commercialized or less costly than the product candidates we may develop or they may develop proprietary technologies or secure patent protection that we may need for the development of our technologies and products. We believe the key competitive factors that will affect the development and commercial success of our future product candidates are efficacy, safety, tolerability, reliability, convenience of use, price and reimbursement.

We anticipate competing with the largest biopharmaceutical companies in the world, as well as a broad range of smaller biotechnology companies which are currently conducting research in cellular therapies, either alone or in partnerships with other parties, and all of which have or may have greater financial and human resources than we currently have. In addition to these fully integrated biopharmaceutical companies, we also compete with those companies whose products target the same indications as our potential product candidates. Many third parties compete with us in developing various approaches to cancer and autoimmune therapies. They include pharmaceutical companies, biotechnology companies, academic

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institutions and other research organizations. Any treatments developed by our competitors could be superior to any product candidates we may develop. It is possible that these competitors will succeed in developing technologies that are more effective than the RCTs that we have been developing or that would render any cancer targeted RCTs that we may develop obsolete or noncompetitive. We anticipate that we will face increased competition in the future as additional companies enter our market and scientific developments surrounding other cancer and autoimmune therapies continue to accelerate.

There are at least two companies leveraging red blood cells to develop therapeutics for cancer and/or immune tolerance. Erytech Pharma SA is using reversible hypotonic and hypertonic osmotic stress to encapsulate drug substances inside of red blood cells to create product candidates for use in cancer and orphan diseases. SQZ Biotechnologies Company is pursuing applications in cancer, infectious disease and autoimmune diseases using a variety of cell-based approaches, including red blood cells.

Outside of RBC-based competition, there are a number of companies competing in our target therapeutic areas. Within oncology, multiple large and small companies are developing novel immune stimulatory agents, such as Nektar Therapeutics, which is developing a polymer-conjugated IL-15, and Genmab, which is developing a bispecific antibody targeting PD-L1 and 4-1BB. Others are developing activated and engineered NK cell product candidates as cancer therapeutics against both hematologic and solid tumor malignancies, such as Fate Therapeutics. Many companies are developing therapies to generate antigen-specific immune responses against HPV-positive cancers, such as BioNTech SE using RNA and Inovio Pharmaceuticals, Inc. using DNA-based therapy. Finally, multiple companies are developing novel approaches to restore immune tolerance, such as Anokion SA, which is developing engineered proteins for celiac disease, Type 1 diabetes and multiple sclerosis, Cour Pharmaceuticals, which is developing nanoparticle technology for the treatment of celiac disease and Type 1 diabetes, and Cellerys AG, which is developing a peptide-coupled cell therapy for the treatment of multiple sclerosis.

In addition to the companies described above, we anticipate competing with the largest biopharmaceutical companies in the world, such as Novartis AG, Gilead Sciences, Inc., Amgen, Inc., F. Hoffman-La Roche AG (Roche), Johnson & Johnson and Pfizer, Inc.

Even if we obtain regulatory approval to market any product candidates we may develop, the availability and price of our competitors’ products could limit the demand and the price we are able to charge for such product candidates. We may not be able to implement our business plan if the acceptance of our product candidates is inhibited by price competition or the reluctance of physicians to switch from existing methods of treatment to our product candidates, or if physicians switch to other new drug or biologic products or choose to reserve our product candidates for use in limited circumstances.

Even if a product candidate we may develop receives marketing approval, it may fail to achieve the degree of market acceptance by physicians, patients, third-party payors and others in the medical community necessary for commercial success.

If any product candidate we may develop receives marketing approval, whether as a single agent or in combination with other therapies, it may nonetheless fail to gain sufficient market acceptance by physicians, patients, third-party payors, and others in the medical community. For example, other cancer treatments like chemotherapy, radiation therapy and immunotherapy are well established in the medical community, and doctors may continue to rely on these therapies. If the product candidates we may develop do not achieve an adequate level of acceptance, we may not generate significant product revenues and we may not become profitable. The degree of market acceptance of any product candidate, if approved for commercial sale, will depend on a number of factors, including:

•efficacy, safety and potential advantages compared to alternative treatments;

•product labeling, product insert, or warning requirements of the FDA or other regulatory authorities;

•any restrictions on the use of our products together with other medications or restrictions on the use of our products in certain types of patients;

•convenience and ease of administration compared to alternative treatments;

•the timing of market introduction of our product candidates as well as competitive products;

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

•public perception of new therapies, including cellular therapies;

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•the strength of marketing and distribution support;

•the ability to offer our products, if approved, for sale at competitive prices;

•the ability to obtain sufficient third-party insurance coverage and adequate reimbursement, including with respect to the use of the approved product as a combination therapy;

•the willingness of patients to pay out-of-pocket in the absence of sufficient payor coverage;

•adoption of a companion diagnostic and/or complementary diagnostic; and

•the prevalence and severity of any side effects associated with our product candidates.

If any of the product candidates we may develop are approved but do not achieve an adequate level of acceptance by patients, physicians and payors, we may not recognize sufficient revenue from such product candidates to become or remain profitable. Before granting reimbursement approval, healthcare payors may require us to demonstrate that our product candidates, in addition to treating these target indications, also provide incremental health benefits to patients. Our efforts to educate the medical community and third-party payors about the benefits of our product candidates may require significant resources and may never be successful.

Cellular therapies are a novel approach and negative perception of any product candidates that we may develop could adversely affect our ability to conduct our business or obtain regulatory approvals for such product candidates.

Cellular therapies in general, and red blood cell therapies in particular, remain novel and unproven therapies, with no red blood cell therapy approved to date in the United States, the United Kingdom or the European Union. Red blood cell therapies may not gain the acceptance of the public or the medical community. For example, CAR-Ts and other cellular therapies have in some cases caused severe side effects and even mortality and their broader use may therefore be limited. Although the therapies we have been developing are fundamentally different than these earlier cellular therapies, they may be viewed in the same vein, limiting their market acceptance. Further, the use of potent T cell and NK cell stimulation as a potential treatment for solid or hematological cancers is a recent scientific development and may not become broadly accepted by physicians, patients, hospitals, cancer treatment centers and others in the medical community.

Our success will depend upon physicians who specialize in the treatment of diseases targeted by our future product candidates prescribing treatments that involve the use of such product candidates in lieu of, or in addition to, existing treatments with which they are more familiar and for which greater clinical data may be available. Adverse events in clinical trials of any product candidates we may develop or in clinical trials of others developing similar products and the resulting publicity, as well as any other adverse events in the field of cellular therapies, could result in a decrease in demand for any product that we may develop. In addition, responses by the U.S., state or foreign governments to negative public perception or ethical concerns may result in new legislation or regulations that could limit our ability to develop or commercialize any product candidates, obtain or maintain regulatory approval or otherwise achieve profitability. More restrictive statutory regimes, government regulations or negative public opinion would have an adverse effect on our business, financial condition, results of operations and prospects and may delay or impair the development and commercialization of our potential product candidates or demand for any products we may develop.

We currently have no marketing and sales organization and have no experience in marketing products. If we are unable to establish marketing and sales capabilities or enter into agreements with third parties to market and sell any products we may develop, we may not be able to generate product revenue.

We currently have no sales, marketing or distribution capabilities and have no experience in marketing products. We may develop an in-house marketing organization and sales force, which will require significant capital expenditures, management resources and time. In the event we develop and deploy these capabilities, we will have to compete with other pharmaceutical and biotechnology companies to recruit, hire, train and retain marketing and sales personnel.

In addition to establishing internal sales, marketing and distribution capabilities, we may pursue collaborative arrangements regarding the sales and marketing of any product candidates we may develop for which we have obtained marketing approval, however, there can be no assurance that we will be able to establish or maintain such collaborative arrangements, or if we are able to do so, that they will have effective sales forces. Any revenue we receive will depend upon the efforts of such third parties, which may not be successful. We may have little or no control over the marketing and sales efforts of such third parties and our revenue from product sales may be lower than if we had commercialized the product candidates

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ourselves. We also face competition in our search for third parties to assist us with the sales and marketing efforts of any future products we may develop.

There can be no assurance that we will be able to develop in-house sales and distribution capabilities or establish or maintain relationships with third-party collaborators to commercialize any product in the United States or overseas.

A variety of risks associated with marketing our product candidates internationally could materially adversely affect our business.

If we were to seek regulatory approval of our product candidates outside of the United States and, accordingly, be subject to additional risks related to operating in foreign countries if we obtain the necessary approvals, including:

•differing regulatory requirements in foreign countries;

•unexpected changes in tariffs, trade barriers, price and exchange controls and other regulatory requirements;

•economic weakness in domestic or foreign markets, including weaknesses caused by geopolitical instability;

•rising inflation in the economies in which we operate, which could increase our current and future cost of labor, clinical trial costs, supply costs, manufacturing costs, and other operating expenses;

•compliance with tax, employment, immigration and labor laws for employees living or traveling abroad;

•foreign taxes, including withholding of payroll taxes;

•foreign currency fluctuations, which could result in increased operating expenses and reduced revenue, and other obligations incident to doing business in another country;

•difficulties staffing and managing foreign operations;

•workforce uncertainty in countries where labor unrest is more common than in the United States;

•potential liability under the Foreign Corrupt Practices Act, or FCPA, or comparable foreign regulations;

•challenges enforcing our contractual and intellectual property rights, especially in those foreign countries that do not respect and protect intellectual property rights to the same extent as the United States;

•production shortages resulting from any events affecting raw material supply or manufacturing capabilities abroad; and

•business interruptions resulting from geo-political actions, including war and terrorism or global pandemics, including but not limited to, the ongoing COVID-19 pandemic.

These and other risks associated with our international operations may materially adversely affect our ability to attain or maintain profitable operations.

Risks related to our business operations

The effects of health epidemics like the ongoing COVID-19 pandemic, including recurring surges and waves of infection and emergent variants of the coronavirus, in regions where we, or the third parties on which we rely, have business operations has affected, and may continue to affect, our business, including our preclinical studies and research and development efforts. The ongoing COVID-19 pandemic could materially affect our operations, including at our headquarters in Massachusetts, as well as the businesses or operations of the third parties with whom we conduct business, or may conduct business with.

In response to the ongoing COVID-19 pandemic, national, state, and local governments have continued to implement orders and recommendations to attempt to reduce the further spread of the disease, including travel restrictions, limitations on public gatherings, remote schooling, social distancing requirements and limitations on services and infrastructure. Although many restrictions have been eased or lifted in light of vaccination rates and as cases in the United States, including Massachusetts and Rhode Island, have decreased, protocols may be reinstated or become more restrictive if the United States or certain areas experience a resurgence of infections, as has been the case with the Omicron variant.

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Fluctuation in infection rates in the regions in which we have business operations has resulted in periodic changes in restrictions that vary from region to region and require vigilant attention and rapid response to new or reinstated restrictions. The duration and severity of the pandemic, as well as periodic spikes in infection rates, new strains of the virus that causes COVID-19, local outbreaks and resurgence of the virus, and the broad availability of effective vaccines and treatments have impacted, and may continue to impact, our preclinical studies and other business operations. Our suppliers and vendors are subject to such restrictions and orders and have been and may continue to be impacted. While not materially adversely affected, our business continues to experience the impact of COVID-19 on our supply chain and vendor operations. The ultimate extent of such impact, including on the supply chain for our preclinical activities, will depend on future developments, which are highly uncertain and cannot be predicted with confidence, such as the duration of the pandemic, the severity of COVID-19, or the effectiveness of actions and vaccinations to contain and treat COVID-19. The continued effects of COVID-19 globally, including the identification of new strains of COVID-19, could continue to adversely impact our preclinical studies and other business operations in the United States. Any continuing negative impact COVID-19 has on the advancement of any product candidates we may develop, including on the availability of study data, could cause costly delays to future clinical trial activities, which could adversely affect our ability to obtain regulatory approval for and to commercialize any future product candidates, increase our operating expenses, and have a material adverse effect on our financial results. To the extent the ongoing COVID-19 pandemic adversely affects our business and financial results and those of third parties on which we rely, it may also have the effect of heightening many of the other risks described in this “Risk Factors” section.

We have seen in the past, and may continue to see in the future, the effect that the ongoing COVID-19 pandemic has had on the ability to recruit and retain principal investigators and site staff who, as healthcare providers, may have heightened exposure to COVID-19 if an outbreak occurs in their geography. COVID-19 may also affect the availability of, and access to, study sites generally. Key clinical trial activities, such as site monitoring, have experienced interruptions due to restrictions in travel, and some patients have been, and may continue to be, unwilling to enroll in our trials or unable to comply with clinical trial protocols, including as a result of quarantines or travel restrictions which impede patient movement or interrupt healthcare services. Such interruptions to clinical activities and impacts on enrollment could delay our ability to conduct future clinical trials or release clinical trial results. While not material, the spread of COVID-19 has in some cases negatively affected the operations at our third-party vendors, which has resulted in delays and disruptions in the supply of some components of our past product candidates and could impact the supply of any future product candidates. COVID-19 may also affect employees of third-party CROs located in affected geographies that we may rely upon to carry out future clinical trials. In addition, we have in the past taken, and may in the future take, temporary precautionary measures intended to help minimize the risk of the virus to our employees, including temporarily requiring all employees to work remotely, suspending all non-essential travel worldwide for our employees, and discouraging employee attendance at industry events and in-person work-related meetings, which could negatively affect our business.

Additionally, since the beginning of the ongoing COVID-19 pandemic, several vaccines for COVID-19 have received Emergency Use Authorization by the FDA and a number of those later received marketing approval. Additional vaccines may be authorized or approved in the future. The resultant demand for vaccines and potential for manufacturing facilities and materials to be commandeered under the Defense Production Act of 1950, or equivalent foreign legislation, has in some instances made it more difficult, or has delayed our ability, to timely obtain materials for our research and development efforts and other business operations.

We cannot presently predict the scope and severity of the impact of the COVID-19 pandemic or its impact on our business. Despite the availability of vaccines and improved treatment options, we may continue to see widespread effects from the ongoing COVID-19 pandemic, including as a result of resurgences of cases, particularly with recently emerged or future variants that are resistant to the vaccines and treatment alternatives. If we or any of the third parties with whom we engage were to experience 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 operation and financial condition.

Actions that we have taken to streamline our business, including the discontinuation of clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors and our workforce reductions, may not be as effective as anticipated and could have a negative impact on our results of operations.

As previously disclosed, in connection with our Reorganization Plan we implemented a workforce reduction and discontinued our ongoing clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors. We undertook these steps in an effort to streamline our business, reduce expenses and conserve cash. However, there can be no assurance that these efforts will result in the expected cost-cutting and cash-savings, or otherwise create any shareholder value, particularly in light of the recent depletion of cash from the repayment of amounts outstanding under our SLR Loan Agreement and the implementation of our Strategic Plan, which is focused on pursuing strategic alternatives and significantly reduced our operations. These undertakings were, and the reduction in our workforce may continue to be,

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disruptive to our limited operations, particularly given the challenges posed by the COVID-19 pandemic, including by distracting management from our core business, affecting employee productivity and morale, or impacting our ability to hire or retain key personnel, any of which could, in turn materially and adversely impact our operations. In addition, such actions could impair our development efforts could make it more difficult for us to deploy resources towards business development, or financial or other strategic, opportunities.

If we lose any team members, our ability to pursue strategic alternatives will be materially and adversely effected.

Our ability to pursue strategic alternatives depends upon our ability to retain our core team of personnel through this process. The loss of the services of any of our remaining key employees and officers, and our inability to find suitable replacements, could prevent us from pursuing or implementing any strategic alternative.

Our internal computer systems, or those used by our CROs, any future CROs or CMOs or other contractors or consultants, may fail or suffer security breaches, and our intellectual property is potentially vulnerable to cyber-attacks.

Our intellectual property, other proprietary technology, and other sensitive company information is dependent on sophisticated information technology systems and is potentially vulnerable to cyber-attack, loss, damage, destruction from system malfunction, computer viruses, loss of data privacy, or misappropriation or misuse of it by those with permitted access, and other events. While we have invested to protect our intellectual property and other information, and continue to upgrade and enhance our systems to keep pace with continuing changes in information processing technology, there can be no assurance that our precautionary measures will prevent breakdowns, breaches, cyber-attacks, or other events. Such events could have a material adverse effect on our reputation, financial condition, or results of operations.

Further, despite the implementation of security measures, the internal computer systems of our CROs, any future CROs or CMOs and other contractors and consultants we may work with are likewise subject to such vulnerabilities. While we have not experienced any such material system failure or security breach to date (and while we are not aware of such a failure or breach at any of such third parties), if such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our or their development programs and our business operations. For example, the loss of clinical trial data from any future clinical trials we may conduct could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. Likewise, we currently rely on outside vendors to supply raw materials and other important components, such as red blood cells, which are used in our product development efforts, and similar events relating to their computer systems could also have a material adverse effect on our business. 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 confidential or proprietary information, we could incur liability and the further development and commercialization of our product candidates could be delayed.

Risks related to litigation and noncompliance with applicable laws or regulations

If product liability lawsuits are brought against us, we may incur substantial liabilities and may be required to limit commercialization of any product candidates we may develop.

We face an inherent risk of product liability as a result of testing past and future product candidates in clinical trials and will face an even greater risk if we commercialize any products. For example, we may be sued if any of our product candidates cause or are perceived to cause injury or are found to be otherwise unsuitable during clinical trials, manufacturing, marketing or sale. Any such product liability claims may include allegations of defects in manufacturing, defects in design, a failure to warn of dangers inherent in the product, negligence, strict liability or a breach of warranties. Claims could also be asserted under state consumer protection acts. If we cannot successfully defend ourselves against product liability claims, we may incur substantial liabilities or be required to limit commercialization of our product candidates. Even successful defense would require significant financial and management resources. Regardless of the merits or eventual outcome, liability claims may result in:

•inability to bring a product candidate to the market;

•decreased demand for our products;

•injury to our reputation;

•withdrawal of clinical trial participants and inability to continue clinical trials;

•initiation of investigations by regulators;

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•costs to defend the related litigation;

•diversion of management’s time and our resources;

•substantial monetary awards to trial participants or patients;

•product recalls, withdrawals or labeling, marketing or promotional restrictions;

•loss of revenue;

•exhaustion of any available insurance and our capital resources;

•the inability to commercialize any product candidate; and

•declines in our share price.

Our inability to obtain sufficient product liability insurance at an acceptable cost to protect against potential product liability claims could prevent or inhibit the commercialization of products we may develop, alone or with collaborators. If and when coverage is secured, our insurance policies may also have various exclusions, and we may be subject to a product liability claim for which we have no coverage. We may have to pay any amounts awarded by a court or negotiated in a settlement that exceed our coverage limitations or that are not covered by our insurance, and we may not have, or be able to obtain, sufficient capital to pay such amounts. Even if our agreements with any future corporate collaborators entitle us to indemnification against losses, such indemnification may not be available or adequate should any claim arise.

Our employees, independent contractors, consultants, commercial partners and vendors may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements.

We are exposed to the risk of employee fraud or other illegal activity by our employees, independent contractors, consultants, commercial partners and vendors. Misconduct by these parties could include intentional, reckless and/or negligent conduct, including failure to comply with the laws of the FDA and other similar foreign regulatory bodies, failure to provide true, complete and accurate information to the FDA and other similar foreign regulatory bodies, failure to comply with manufacturing standards we have established, failure to comply with healthcare fraud and abuse laws in the United States and similar foreign fraudulent misconduct laws, and failure to report financial information or data accurately or to disclose unauthorized activities to us. If we obtain FDA approval of any product candidates we may develop and begin commercializing those products in the United States, our potential exposure under applicable law will increase significantly, and our costs associated with compliance with such laws are also likely to increase. These laws may impact, among other things, our activities with principal investigators and research patients, as well as proposed and future sales, marketing and education programs.

Our relationships with healthcare providers and physicians 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, contractual damages, reputational harm and diminished profits and future earnings.

Healthcare providers, physicians and third-party payors in the United States and elsewhere play a primary role in the recommendation and prescription of pharmaceutical products. Arrangements with third-party payors and customers can expose pharmaceutical manufacturers to broadly applicable fraud and abuse and other healthcare laws and regulations, including, without limitation, the federal Anti-Kickback Statute and the federal False Claims Act, which may constrain the business or financial arrangements and relationships through which such companies sell, market and distribute pharmaceutical products. In particular, the promotion, sales and marketing of healthcare items and services, as well as certain business arrangements in the healthcare industry, are subject to extensive laws designed to prevent fraud, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, structuring and commission practices, certain customer incentive programs and other business arrangements generally. Activities subject to these laws also involve the improper use of information obtained in the course of patient recruitment for clinical trials. See the section entitled, “Business — Government Regulation — Other healthcare laws” in our Annual Report on Form 10-K for the year ended December 31, 2021.

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. 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. Additionally, the

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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.

Ensuring that our internal operations and business arrangements with third parties comply with applicable healthcare laws and regulations can be time- and resource-consuming, can divert our attention from our business and have involved, and will continue to involve, substantial costs. We have adopted a code of business conduct and ethics, but it is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent inappropriate conduct 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 be in compliance with such laws or regulations. It is possible that governmental and enforcement authorities will conclude that our business practices may not comply with current or future statutes, regulations or case law interpreting applicable fraud and abuse or other healthcare laws and regulations. If any enforcement 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, disgorgement, monetary fines, possible exclusion from participation in Medicare, Medicaid and other federal healthcare programs, individual imprisonment, contractual damages, reputational harm, diminished profits and future earnings, and curtailment 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, any of which could adversely affect our ability to operate our business and our results of operations. 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, manufacturers or other providers or entities with whom we do business is 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. Prohibitions or restrictions on sales or withdrawal of future marketed products due to noncompliance with applicable laws could materially affect business in an adverse way. If any of the above occur, our ability to operate our business and our results of operations could be adversely affected.

We may become involved in lawsuits to protect or enforce our patents and other intellectual property rights, which could be expensive, time-consuming, and unsuccessful.

Competitors may infringe our patents or the patents of our licensing partners, or we may be required to defend against claims of infringement. In addition, our patents or the patents of our licensing partners also may become involved in inventorship, priority or validity disputes. To counter or defend against such claims can be expensive and time-consuming. In an infringement proceeding, a court may decide that a patent owned or in-licensed by us is invalid or unenforceable or that the other party’s use of our patented technology falls under the safe harbor to patent infringement under 35 U.S.C. §271(e)(1), or may refuse to stop the other party from using the technology at issue on the grounds that our owned and in-licensed patents do not cover the technology in question. An adverse result in any litigation proceeding could put one or more of our owned or in-licensed patents at risk of being invalidated or interpreted narrowly. Even if we establish infringement, the court may decide not to grant an injunction against further infringing activity and instead award only monetary damages, which may or may not be an adequate remedy. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation.

Even if resolved in our favor, litigation or other legal proceedings relating to intellectual property claims may cause us to incur significant expenses and could distract our personnel from their normal responsibilities. In addition, there could be public announcements of the results of hearings, motions, or other interim proceedings or developments, and if securities analysts or investors perceive these results to be negative, it could have a substantial adverse effect on the price of our common stock. Such litigation or proceedings could substantially increase our operating losses and reduce the resources available for development activities or any future sales, marketing, or distribution activities. We may not have sufficient financial or other resources to conduct such litigation or proceedings adequately. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their greater financial resources and more mature and developed intellectual property portfolios. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace.

If we fail to comply with environmental, health and safety laws and regulations, we could become subject to fines or penalties or incur costs that could have a material adverse effect on the success of our business.

We 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. Our research and development activities involve the use of biological and hazardous materials and produce hazardous waste products. We generally contract with third parties for the disposal of these materials and wastes. We cannot eliminate the risk of

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contamination or injury from these materials, which could cause an interruption of our research and development efforts, business operations and any future commercialization efforts or environmental damage resulting in costly clean-up and liabilities under applicable laws and regulations governing the use, storage, handling and disposal of these materials and specified waste products. Although we believe that the safety procedures we have implemented for handling and disposing of these materials generally comply with the standards prescribed by these laws and regulations, we cannot guarantee that this is the case. In the event of accidental contamination or injury from hazardous materials, we may be held liable for any resulting damages and such liability could exceed our resources and state or federal or other applicable authorities may curtail our use of certain materials and/or interrupt our business operations. Furthermore, environmental laws and regulations are complex, change frequently and have tended to become more stringent. We cannot predict the impact of any changes in, and cannot be certain of our future compliance with, such laws and regulations. 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 production efforts. Failure to comply with these laws and regulations also may result in substantial fines, penalties or other sanctions.

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 or other work-related injuries, this insurance may not provide adequate coverage against potential liabilities. We do not carry specific biological waste or hazardous waste insurance coverage or workers compensation, property and casualty or general liability insurance policies that include coverage for damages and fines arising from biological or hazardous waste exposure or contamination.

We are subject to certain U.S. and foreign anti-corruption, anti-money laundering, export control, sanctions, and other trade laws and regulations. We can face serious consequences for violations.

Among other matters, U.S. and foreign anti-corruption, anti-money laundering, export control, sanctions, and other trade laws and regulations, which we collectively refer to as Trade Laws, prohibit companies and their employees, agents, clinical research organizations, legal counsel, accountants, consultants, contractors, and other partners from authorizing, promising, offering, providing, soliciting, or receiving, directly or indirectly, corrupt or improper payments or anything else of value to or from recipients in the public or private sector. Violations of Trade Laws can result in substantial criminal fines and civil penalties, imprisonment, the loss of trade privileges, debarment, tax reassessments, breach of contract and fraud litigation, reputational harm, and other consequences. We have direct or indirect interactions with officials and employees of government agencies and government-affiliated hospitals, universities, and other organizations. We also expect our non-U.S. activities to increase in time. We currently engage, and plan to continue to engage, third parties for clinical trials and/or to obtain necessary permits, licenses, patent registrations, and other regulatory approvals and we can be held liable for the corrupt or other illegal activities of our personnel, agents, or partners, even if we do not explicitly authorize or have prior knowledge of such activities.

Risks related to government regulation

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

We intend to submit marketing applications in both the U.S. and in selected foreign jurisdictions. 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 and maintaining regulatory approval of any of our 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 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 nonclinical 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.

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 and/or receive applicable marketing approvals, our target market will be reduced and our ability to realize the full market potential of any product candidates we may develop will be harmed.

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If we are not able to obtain, or if there are delays in obtaining, required regulatory approvals for the product candidates we may develop, we will not be able to commercialize, or will be delayed in commercializing, such product candidates, and our ability to generate revenue will be materially impaired.

Our future product candidates and the activities associated with their development and commercialization, including their design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale, distribution, import and export are subject to comprehensive regulation by the FDA and other regulatory agencies in the United States and by comparable authorities in other countries. Before we can commercialize any of the product candidates we may develop, we must obtain marketing approval. As a preclinical stage company, we have not received approval to market any product candidate from regulatory authorities in any jurisdiction and it is possible that none of the product candidates we may develop in the future will ever obtain regulatory approval. We, as a company, have no experience in filing and supporting the applications necessary to gain regulatory approvals and expect to have to rely on third-party CROs and/or regulatory consultants to assist us in this process. Securing regulatory approval requires the submission of extensive preclinical and clinical data and supporting information to the various regulatory authorities for each therapeutic indication to establish the drug candidate’s safety and efficacy. Securing regulatory approval also requires the submission of information about the drug manufacturing process to, and inspection of manufacturing facilities and clinical sites by, the relevant regulatory authority. Our future product candidates may not be effective, may be only moderately effective or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude our obtaining marketing approval or prevent or limit commercial use.

The process of obtaining regulatory approvals, both in the United States and abroad, if approval is obtained at all, is expensive, may take many years, particularly if additional clinical trials are required, and can vary substantially based upon a variety of factors, including the type, complexity and novelty of the product candidates involved. Changes in marketing approval policies during the development period, changes in or the enactment of additional statutes or regulations, or changes in regulatory review for each submitted IND, Premarket Approval, or PMA, BLA or equivalent application types, may cause delays in the approval or rejection of an application. The FDA and comparable authorities in other countries 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. Any product candidates we may develop could be delayed in receiving, or fail to receive, regulatory approval for many reasons, including the following:

•the FDA or comparable foreign regulatory authorities may disagree with the design or implementation of our clinical trials;

•we may be unable to demonstrate to the satisfaction of the FDA or comparable foreign regulatory authorities that a drug candidate is safe and effective for its proposed indication or a related companion diagnostic is suitable to identify appropriate patient populations;

•the results of clinical trials may not meet the level of statistical significance required by the FDA or comparable foreign regulatory authorities for approval;

•we may be unable to demonstrate that a product candidate’s clinical and other benefits outweigh its safety risks;

•the FDA or comparable foreign regulatory authorities may disagree with our interpretation of data from preclinical studies or clinical trials;

•the data collected from clinical trials of our product candidates may not be sufficient to support the submission of an BLA or other submission or to obtain regulatory approval in the United States or elsewhere;

•the FDA or comparable foreign regulatory authorities may fail to approve our manufacturing processes or facilities or those of third-party manufacturers with which we may contract for clinical and commercial supplies; and

•the approval policies or regulations of the FDA or comparable foreign regulatory authorities may significantly change in a manner rendering our clinical data insufficient for approval.

Of the large number of drugs in development, only a small percentage successfully complete the FDA or foreign regulatory approval processes and are commercialized. The lengthy approval process, as well as the unpredictability of future clinical trial results may result in our failing to obtain regulatory approval to market our future product candidates, which would significantly harm our business, results of operations and prospects.

We expect the novel nature of our future product candidates to create further challenges in obtaining regulatory approval. As a result, our ability to develop product candidates and obtain regulatory approval may be significantly impacted.

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For example, the general approach for FDA approval of a new biologic or drug is for sponsors to seek licensure or approval based on dispositive data from well-controlled, Phase 3 clinical trials of the relevant product candidate in the relevant patient population. Phase 3 clinical trials typically involve hundreds of patients, have significant costs and take years to complete.

The FDA may also require a panel of experts, referred to as an Advisory Committee, to deliberate on the adequacy of the safety and efficacy data to support approval. The opinion of the Advisory Committee, although not binding, may have a significant impact on our ability to obtain approval of any product candidates that we may develop based on the completed clinical trials. Additionally, due to the ongoing COVID-19 pandemic, the conduct of Advisory Committee meetings may be disrupted or delayed and the impact that may have on the overall timing of regulatory approvals is uncertain.

Moreover, regulatory agencies may require the development and approval of genetic or biomarker diagnostic tests in order to advance our future product candidates to clinical trials or potential commercialization. Accordingly, the regulatory approval pathway for such product candidates may be uncertain, complex, expensive and lengthy, and approval may not be obtained.

In addition, even if we were to obtain approval, regulatory authorities may approve our future product candidates for fewer or more limited indications than we request, may not approve the price we intend to charge for our products, may grant approval contingent on the performance of costly post-marketing clinical trials, or may approve a product candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that product candidate. Any of the foregoing scenarios could materially harm the commercial prospects for our future product candidates.

If we experience delays in obtaining approval or if we fail to obtain approval of our future product candidates, the commercial prospects for our product candidates may be harmed and our ability to generate revenues will be materially impaired.

Breakthrough Therapy Designation, Fast Track Designation or Regenerative Medicine Advanced Therapy Designation by the FDA, even if granted for any future product candidates, may not lead to a faster development, regulatory review or approval process, and it does not increase the likelihood that any such product candidates will receive marketing approval in the United States.

We may seek a Breakthrough Therapy Designation for some of our future product candidates. A breakthrough therapy is defined as a therapy that is intended, alone or in combination with one or more other therapies, to treat a serious or life-threatening disease or condition, and preliminary clinical evidence indicates that the therapy may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. For therapies that have been designated as breakthrough therapies, interaction and communication between the FDA and the sponsor of the trial can help to identify the most efficient path for clinical development while minimizing the number of patients placed in ineffective control regimens. Therapies designated as breakthrough therapies by the FDA may also be eligible for priority review and accelerated approval. Designation as a breakthrough therapy is within the discretion of the FDA. Accordingly, even if we believe one of our future product candidates meets the criteria for designation as a breakthrough therapy, the FDA may disagree and instead determine not to make such designation. In any event, the receipt of a Breakthrough Therapy Designation for a product candidate may not result in a faster development process, review or approval compared to therapies considered for approval under conventional FDA procedures and does not assure ultimate approval by the FDA. In addition, even if one or more of our future product candidates qualify as breakthrough therapies, the FDA may later decide that such product candidates no longer meet the conditions for qualification.

We may seek Fast Track Designation for some of our future product candidates. If a therapy is intended for the treatment of a serious or life-threatening condition and the therapy demonstrates the potential to address unmet medical needs for this condition, the therapy sponsor may apply for Fast Track Designation. The FDA has broad discretion whether or not to grant this designation, so even if we believe a particular product candidate is eligible for this designation; we cannot assure our stockholders that the FDA would decide to grant it. Even if we do receive Fast Track Designation, we may not experience a faster development process, review or approval compared to conventional FDA procedures. The FDA may withdraw Fast Track Designation if it believes that the designation is no longer supported by data from our clinical development program. Fast Track Designation alone does not guarantee qualification for the FDA’s priority review procedures.

We may seek Regenerative Medicine Advanced Therapy, or RMAT, designation for one or more of our future product candidates. RMAT designation by the FDA is intended to expedite development and review of any drug that meets the following criteria: it qualifies as a RMAT, which is defined as a cell therapy, therapeutic tissue engineering product, human

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cell and tissue product, or any combination product using such therapies or products, with limited exceptions; it is intended to treat, modify, reverse, or cure a serious or life-threatening disease or condition; and preliminary clinical evidence indicates that the drug has the potential to address unmet medical needs for such a disease or condition. Like Breakthrough Therapy Designation, RMAT designation provides potential benefits that include more frequent meetings with the FDA to discuss the development plan for the product candidate, and eligibility for rolling review and priority review. Products granted RMAT designation may also be eligible for accelerated approval on the basis of a surrogate or intermediate endpoint reasonably likely to predict long-term clinical benefit, or reliance upon data obtained from a meaningful number of sites, including through expansion to additional sites. RMAT-designated products that receive accelerated approval may, as appropriate, fulfill their post-approval requirements through the submission of clinical evidence, clinical trials, patient registries, or other sources of real-world evidence, such as electronic health records; through the collection of larger confirmatory data sets; or via post-approval monitoring of all patients treated with such therapy prior to approval of the therapy. There is no assurance that we will be able to obtain RMAT designation for any of our future product candidates. RMAT designation does not change the FDA’s standards for product approval, and there is no assurance that such designation will result in expedited review or approval or that the approved indication will not be narrower than the indication covered by the designation. Additionally, RMAT designation can be revoked if the criteria for eligibility cease to be met as clinical data emerges.

We may seek priority review designation for one or more of our future product candidates, but we might not receive such designation, and even if we do, such designation may not lead to a faster development or regulatory review or approval process.

If the FDA determines that a product candidate offers a treatment for a serious condition and, if approved, the product would provide a significant improvement in safety or effectiveness, the FDA may designate the product candidate for priority review. A priority review designation means that the goal for the FDA to review an application is six months, rather than the standard review period of ten months. We may request priority review for our future product candidates. The FDA has broad discretion with respect to whether or not to grant priority review status to a product candidate, so even if we believe a particular product candidate is eligible for such designation or status, the FDA may decide not to grant it. Moreover, a priority review designation does not necessarily result in expedited development or regulatory review or approval process or necessarily confer any advantage with respect to approval compared to conventional FDA procedures. Receiving priority review from the FDA does not guarantee approval within the six-month review cycle or at all.

Our future product candidates may face competition from biosimilars approved through an abbreviated regulatory pathway.

The Biologics Price Competition and Innovation Act of 2009, or BPCIA, created an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with an FDA-approved reference biological product. 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 approved 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 approved. During this 12-year period of exclusivity, another company may still market a competing version of the reference product if the FDA approves a BLA for the competing product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity, and potency of the other company’s product. 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.

We believe that any of our product candidates approved as a biological product under a BLA should qualify for the 12-year period of exclusivity. However, there is a risk that this exclusivity could be shortened due to congressional action or otherwise, or that the FDA will not consider our investigational medicines to be reference products for competing products, potentially creating the opportunity for generic competition sooner than anticipated. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. Moreover, 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.

We may fail to obtain and maintain orphan drug designations from the FDA for our future product candidates.

Our strategy includes filing for orphan drug designation for our future product candidates, where available. Under the Orphan Drug Act, the FDA may grant orphan drug designation to a drug or biologic intended to treat a rare disease or condition, which is defined as one occurring in a patient population of fewer than 200,000 in the United States, or a patient population greater than 200,000 in the United States where 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 drug designation entitles

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a party to financial incentives, such as opportunities for grant funding toward clinical trial costs, tax advantages and user-fee waivers. In addition, if a product that has orphan drug designation subsequently receives the first FDA approval for the disease for which it has such designation, the product is entitled to orphan drug exclusivity, which means that the FDA may not approve any other applications, including a full new drug application, or NDA, or BLA, to market the same drug or biologic for the same indication for seven years, except in limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity or where the original manufacturer is unable to assure sufficient product quantity.

We do not know if, when, or how the FDA may change the orphan drug regulations and policies in the future, and it is uncertain how any changes might affect our business. Depending on what changes the FDA may make to its orphan drug regulations and policies, our business could be adversely impacted.

In addition, exclusive marketing rights in the United States may be limited if we seek approval for an indication broader than the orphan-designated indication or may be lost if the FDA later determines that the request for designation was materially defective or if we are unable to assure sufficient quantities of the product to meet the needs of patients with the orphan-designated disease or condition. Further, even if we obtain orphan drug exclusivity for a product, that exclusivity may not effectively protect the product from competition because different drugs with different active moieties may receive and be approved for the same condition, and only the first applicant to receive approval will receive the benefits of marketing exclusivity. Even after an orphan-designated product is approved, the FDA can subsequently approve a later drug with the same active moiety for the same condition if the FDA concludes that the later drug is clinically superior if 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. In addition, while we may seek orphan drug designation for our future product candidates, we may never receive such designations.

Even if we receive regulatory approval of any product candidates or therapies we may develop, we will be subject to ongoing regulatory obligations and continued regulatory review, which may result in significant additional expense and we may be subject to penalties if we fail to comply with regulatory requirements or experience unanticipated problems with our product candidates.

If any product candidates we may develop are approved, they will be subject to ongoing regulatory requirements for manufacturing, labeling, packaging, storage, advertising, promotion, sampling, record-keeping, export, import, conduct of post-marketing studies and submission of safety, efficacy and other post-market information, including both federal and state requirements in the United States and requirements of comparable foreign regulatory authorities. In addition, we will be subject to continued compliance with cGMP and GCP requirements for any clinical trials that we conduct post-approval.

Manufacturers and manufacturers’ facilities are required to comply with extensive FDA, and comparable foreign regulatory authority requirements, including ensuring that quality control and manufacturing procedures conform to cGMP regulations and applicable product tracking and tracing requirements. As such, we and any contract manufacturers we may engage will be subject to continual review and inspections to assess compliance with cGMP and adherence to commitments made in any BLA, other marketing application, and previous responses to inspection observations. Accordingly, we and others with whom we work must continue to expend time, money, and effort in all areas of regulatory compliance, including manufacturing, production and quality control.

Any regulatory approvals that we receive for our future product candidates may be subject to limitations on the approved indicated uses for which the product may be marketed or to the conditions of approval, or contain requirements for potentially costly post-marketing testing, including Phase 4 clinical trials and surveillance to monitor the safety and efficacy of the product candidate. The FDA may also require a risk evaluation and mitigation strategies, or REMS, program as a condition of approval of our future product candidates, which could entail requirements for long-term patient follow-up, a medication guide, physician communication plans or additional elements to ensure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. In addition, if the FDA or a comparable foreign regulatory authority approves any of our future product candidates, we will have to comply with requirements including submissions of safety and other post-marketing information and reports and registration.

The FDA may impose consent decrees or 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 our product candidates, including adverse events of unanticipated severity or frequency, or with our third-party manufacturers or manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution restrictions or other restrictions under a REMS program. Other potential consequences include, among other things:

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•restrictions on the marketing or manufacturing of our products, withdrawal of the product from the market or voluntary or mandatory product recalls;

•fines, warning letters or holds on clinical trials;

•refusal by the FDA to approve pending applications or supplements to approved applications filed by us or suspension or revocation of license approvals;

•product seizure or detention or refusal to permit the import or export of our product candidates; and

•injunctions or the imposition of civil or criminal penalties.

The FDA strictly regulates marketing, labeling, advertising, and promotion of products that are placed on the market. Products may be promoted only for the approved indications and in accordance with the provisions of the approved label. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses of an approved product, and a company that is found to have improperly promoted off-label uses may be subject to significant liability and regulatory enforcement actions.

The policies of the FDA and of other regulatory authorities may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our future product candidates. 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 which would adversely affect our business, prospects and ability to achieve or sustain profitability.

We also cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative or executive action, either in the United States or abroad. For example, certain policies of the current administration in the United States may impact our business and industry. Namely, the current administration has taken several executive actions, including the issuance of a number of executive orders, that could impose significant burdens on, or otherwise materially delay, the FDA’s ability to engage in routine regulatory and oversight activities, such as implementing statutes through rulemaking, issuance of guidance and review and approval of marketing applications. It is difficult to predict how these executive actions, including any executive orders, will be implemented, and the extent to which they will impact the FDA’s ability to exercise its regulatory authority. If these executive actions impose constraints on the FDA’s ability to engage in oversight and implementation activities in the normal course, our business may be negatively impacted.

Healthcare insurance coverage and reimbursement may be limited or unavailable in certain market segments for our future product candidates, if approved, which could make it difficult for us to sell any such product candidates or therapies profitably.

The success of our future product candidates, if approved, depends on the availability of adequate coverage and reimbursement from third-party payors. In addition, because the therapies we have been developing represent new approaches to the treatment of the diseases they target, we cannot be sure that coverage and reimbursement will be available for, or accurately estimate the potential revenue from, our future product candidates or assure that coverage and reimbursement will be available for any product that we may develop. See the section entitled, “Business — Government Regulation — Coverage and Reimbursement” in our Annual Report on Form 10-K for the year ended December 31, 2021.

Patients who are provided medical treatment for their conditions 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 are critical to new product acceptance.

Government authorities and other third-party payors, such as private health insurers and health maintenance organizations, decide which drugs and treatments they will cover and the amount of reimbursement. Coverage and reimbursement by a third-party payor may depend upon a number of factors, including the third-party payor’s determination that use of a product is:

•a covered benefit under its health plan;

•safe, effective and medically necessary;

•appropriate for the specific patient;

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•cost-effective; and

•neither experimental nor investigational.

In the United States, the principal decisions about reimbursement for new medicines are typically made by the Centers for Medicare & Medicaid Services, the agency responsible for administering the Medicare program, or 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. That being said, however, no uniform policy of coverage and reimbursement for products exists among third-party payors. As a result, obtaining coverage and reimbursement approval of a product from a government or other third-party payor is a time-consuming and costly process that could require us to provide to each payor supporting scientific, clinical and cost-effectiveness data for the use of our products on a payor-by-payor basis, with no assurance that coverage and adequate reimbursement will be obtained. Even if we obtain coverage for a given product, the resulting reimbursement payment rates might not be adequate for us to achieve or sustain profitability or may require co-payments that patients find unacceptably high, which may adversely impact physicians’ willingness to prescribe and treat. Further, even if one payor provides coverage for a given product, other payors may not provide coverage for that product. Additionally, third-party payors may not cover, or provide adequate reimbursement for, long-term follow-up evaluations required following the use of product candidates. Patients are unlikely to use our future product candidates unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of such product candidates. Because our future product candidates may have a higher cost of goods than conventional therapies, and may require long-term follow-up evaluations, the risk that coverage and reimbursement rates may be inadequate for us to achieve profitability may be greater. There is significant uncertainty related to insurance coverage and reimbursement of newly approved products and coverage may be more limited than the purposes for which the medicine is approved by the FDA or comparable foreign regulatory authorities. It is difficult to predict at this time what third-party payors will decide with respect to the coverage and reimbursement for our future product candidates.

Moreover, increasing efforts by governmental and other third-party payors in the United States and abroad to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our future product candidates. Increasingly, third-party payors are requiring that drug companies provide them with predetermined discounts from list prices and are challenging the prices charged for medical products. We cannot be sure that reimbursement will be available for any product candidate that we commercialize and, if reimbursement is available, the level of reimbursement. 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 state level, legislatures are increasingly 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. We expect to experience pricing pressures in connection with the sale of any of our future product candidates, if approved, due to the trend toward managed healthcare, the increasing influence of health maintenance organizations, cost containment initiatives and additional legislative changes. We may face competition in the United States for our development candidates and investigational medicines, if approved, from therapies sourced from foreign countries that have placed price controls on pharmaceutical products.

Disruptions at the FDA, the SEC and other government agencies caused by funding shortages or global health concerns could hinder their ability to hire and retain key leadership and other personnel, prevent new products and services from being developed or commercialized in a timely manner or otherwise prevent those agencies from performing normal business functions on which the operation of our business may rely, which could negatively impact our business.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory, and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of the SEC and other government agencies on which our operations may rely, including those that fund research and development activities, is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies may also slow the time necessary for new drugs or biologics to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, over the last

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several years, including most recently from December 22, 2018 to January 25, 2019, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA and the SEC, have had to furlough critical FDA, SEC and other government employees and stop critical activities. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

Since March 2020, when foreign and domestic inspections of facilities were largely placed on hold due to the COVID-19 pandemic, the FDA has been working to resume pre-pandemic inspection activities, including routine surveillance, bioresearch monitoring and pre-approval inspections. Should the 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 FDA 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. Further, if there is inadequate information to make a determination on the acceptability of a facility, the FDA may 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.

European Union drug marketing and reimbursement regulations may materially affect our ability to market and receive coverage for our products in the European Member States.

We intend to seek approval to market our future product candidates in both the United States and in selected foreign jurisdictions. If we obtain approval in one or more foreign jurisdictions for such product candidates, we will be subject to rules and regulations in those jurisdictions. In some foreign countries, particularly certain countries in the European Union, the pricing of pharmaceutical products is subject to governmental control and other market regulations which could put pressure on the pricing and usage of our product candidates. In these countries, pricing negotiations with governmental authorities can take considerable time after obtaining marketing approval of a product candidate. In addition, market acceptance and sales of our future product candidates will depend significantly on the availability of adequate coverage and reimbursement from third-party payors for such product candidates and may be affected by existing and future healthcare reform measures.

Much like the Anti-Kickback Statute prohibition in the United States, the provision of benefits or advantages to physicians to induce or encourage the prescription, recommendation, endorsement, purchase, supply, order or use of medicinal products is also prohibited in the European Union. The provision of benefits or advantages to induce or reward improper performance generally is typically governed by the national anti-bribery laws of European Union Member States, and the Bribery Act 2010 in the United Kingdom. Infringement of these laws could result in substantial fines and imprisonment. E.U. Directive 2001/83/EC, which is the E.U. Directive governing medicinal products for human use, further provides that, where medicinal products are being promoted to persons qualified to prescribe or supply them, no gifts, pecuniary advantages or benefits in kind may be supplied, offered or promised to such persons unless they are inexpensive and relevant to the practice of medicine or pharmacy. This provision has been transposed into the Human Medicines Regulations 2012 and so remains applicable in the United Kingdom despite its departure from the European Union.

Payments made to physicians in certain European Union Member States must be publicly disclosed. Moreover, agreements with physicians often must be the subject of prior notification and approval by the physician’s employer, his or her competent professional organization and/or the regulatory authorities of the individual European Union Member States. These requirements are provided in the national laws, industry codes or professional codes of conduct applicable in the European Union Member States. Failure to comply with these requirements could result in reputational risk, public reprimands, administrative penalties, fines or imprisonment.

In addition, in some foreign countries, including the European Economic Area, or the EEA, the proposed pricing for a drug must be approved before it may be lawfully marketed. The requirements governing drug pricing and reimbursement vary widely from country to country. For example, the European Union provides options for its Member States to restrict the range of medicinal products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. Reference pricing used by various European Union Member States and parallel distribution, or arbitrage between low-priced and high-priced Member States, can further reduce prices. Other European Union Member States allow companies to fix their own prices for drug products, but monitor and control prescription volumes and issue guidance to physicians to limit prescriptions. Instead of approving a specific price for a medicinal product, a Member State may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market. In some countries, we may be required to conduct a clinical trial or other studies that compare the cost-effectiveness of any of our future product candidates to other available therapies in order to obtain or maintain reimbursement or pricing approval. There can be no assurance that any country that has price

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controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our products. Historically, products launched in the European Union do not follow price structures of the United States and generally prices tend to be significantly lower. Publication of discounts by third-party payors or authorities may lead to further pressure on the prices or reimbursement levels within the country of publication and other countries. If pricing is set at unsatisfactory levels or if reimbursement of our products is unavailable or limited in scope or amount, our revenues from sales by us or our strategic partners and the potential profitability of any of our future product candidates in those countries would be negatively affected.

Data collection in Europe and some U.S. states is governed by restrictive regulations governing the use, processing, and cross-border transfer of personal information.

If we begin conducting trials in the EEA or the UK, we will be subject to the data protection laws of the European Union, or the EU, and United Kingdom, or the UK, in relation to personal data we collect from these territories. These laws impose additional obligations and risk upon our business, including substantial expenses and changes to business operations that are required to comply with these laws. The withdrawal of the UK from the EU (Brexit) and the subsequent separation of the data protection regimes of these territories mean we are required to comply with separate data protection laws in the EU and UK which may lead to additional compliance costs and could increase our overall risk. The collection, use, storage, disclosure, transfer, and other processing of personal data in the European Union is governed by the provisions of the General Data Protection Regulation, or EU GDPR, which became effective on May 25, 2018. Further to Brexit, the EU GDPR ceased to apply in the United Kingdom at the end of the transition period on December 31, 2020. As of January 1, 2021, the United Kingdom’s European Union (Withdrawal) Act 2018 incorporated the EU GDPR into United Kingdom law, (referred to as the UK GDPR and together with the EU GDPR, referred to as the GDPR). Failure to comply with the GDPR, and any supplemental European Economic Area, or EEA, country’s national data protection laws which may apply by virtue of the location of the individuals whose personal data we collect, may result in fines and other administrative penalties, including monetary penalties of up to €20/£17.5 million or 4% of worldwide revenue (whichever is higher). The GDPR also confers a private right of action on data subjects and consumer associations to lodge complaints with supervisory authorities, seek judicial remedies, and obtain compensation for damages resulting from violations of the GDPR.

The GDPR imposes several requirements relating to the processing personal data, including the requirement to provide a notice to individuals about personal data processing activities, the lawful basis for processing personal data, having data processing agreements with third parties who process personal data, appointing data protection officers, conducting data protection impact assessments, record-keeping, responding to individuals’ requests to exercise their rights in respect of their personal data, notification of data breaches to the competent national data protection authority, and the implementation of safeguards to protect the security and confidentiality of personal data. The GDPR also imposes several additional requirements relating to the processing of health and other sensitive data which will require us to obtain consent from the individual to whom the personal data relates.

The GDPR imposes strict rules on the transfer of personal data out of the EEA/UK to countries not regarded by the United Kingdom as providing adequate protection, or third countries, including the United States. These transfers are prohibited unless an appropriate safeguard specified by data protection laws is implemented, such as the Standard Contractual Clauses, or SCCs, approved by the European Commission, or a derogation applies. In addition, following the decision of the Court of Justice of the European Union, or CJEU, in Case C-311/18 (Data Protection Commissioner v Facebook Ireland and Maximillian Schrems or Schrems II), transfers made pursuant to the SCCs (and other similar appropriate transfer safeguards) need to be assessed on a case-by-case basis taking into account the legal regime applicable in the destination country, in particular regarding applicable surveillance laws and relevant rights of individuals with respect to the transferred personal data, to ensure an “essentially equivalent” level of protection to that guaranteed in the EEA in the jurisdiction where the data importer is based, or Transfer Equivalence Test.

On June 4, 2021, the European Commission issued new forms of standard contractual clauses for data transfers from controllers or processors in the EEA (or otherwise subject to the GDPR) to controllers or processors established outside the EEA. The new forms of standard contractual clauses will replace the standard contractual clauses that were adopted previously under the Data Protection Directive. The UK is not subject to the European Commission’s new standard contractual clauses but has published its own transfer mechanism, the International Data Transfer Agreement and International Data Transfer Addendum, or IDTA, which enables transfers from the UK. To the extent we transfer personal data from clinical trials in the EEA or the UK and has implemented a similar Transfer Equivalence Test. We will be required to carry out Equivalence Tests and transition to the new form of SCCs and IDTA in relation to our existing agreements with service providers outside the UK/EEA who we utilize for the processing of UK/EEA personal data and any other parties outside the UK/EEA who we transfer UK/EEA personal data to. The international transfer obligations under the EU and UK data protection regimes will require effort and cost, and may result in us needing to make strategic considerations around where EEA/UK personal data is located and which service providers we can utilize for the

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processing of EEA/UK personal data, particularly as the enforcement around GDPR international transfer compliance obligations is currently unclear. Although the UK is regarded as a third country under the EU GDPR, the European Commission has issued a decision recognizing the UK as providing adequate protection under the EU GDPR, or Adequacy Decision, and, therefore, transfers of personal data originating in the EEA to the United Kingdom remain unrestricted. The UK government has confirmed that personal data transfers from the United Kingdom to the European Economic Area remain free flowing. The UK Government has also now introduced a Data Protection and Digital Information Bill, or UK Bill, into the UK legislative process with the intention for this bill to reform the UK’s data protection regime following Brexit. If passed, the final version of the UK Bill may have the effect of further altering the similarities between the UK and EU data protection regime and threaten the UK Adequacy Decision from the EU Commission. This may lead to additional compliance costs and could increase our overall risk.

Laws and regulations governing any international operations we may have in the future may preclude us from developing, manufacturing and selling certain products outside of the United States and require us to develop and implement costly compliance programs.

If we expand our operations outside of the United States, we must dedicate additional resources to comply with numerous laws and regulations in each jurisdiction in which we plan to operate. The FCPA prohibits any U.S. individual or business from paying, offering, authorizing payment or offering of anything of value, directly or indirectly, to any foreign official, political party or candidate for the purpose of influencing any act or decision of the foreign entity in order to assist the individual or business in obtaining or retaining business. The FCPA also obligates companies whose securities are listed in the United States to comply with certain accounting provisions requiring the company to maintain books and records that accurately and fairly reflect all transactions of the corporation, including international subsidiaries, and to devise and maintain an adequate system of internal accounting controls for international operations.

Compliance with the FCPA is expensive and difficult, particularly in countries in which corruption is a recognized problem. In addition, the FCPA presents particular challenges in the pharmaceutical industry, because, in many countries, hospitals are operated by the government, and doctors and other hospital employees are considered foreign officials. Certain payments to hospitals in connection with clinical trials and other work have been deemed to be improper payments to government officials and have led to FCPA enforcement actions.

Various laws, regulations and executive orders also restrict the use and dissemination outside of the United States, or the sharing with certain non-U.S. nationals, of information classified for national security purposes, as well as certain products and technical data relating to those products. If we expand our presence outside of the United States, it will require us to dedicate additional resources to comply with these laws, and these laws may preclude us from developing, manufacturing, or selling certain products and product candidates outside of the United States, which could limit our growth potential and increase our development costs.

The failure to comply with laws governing international business practices may result in substantial civil and criminal penalties and suspension or debarment from government contracting. The SEC also may suspend or bar issuers from trading securities on U.S. exchanges for violations of the FCPA’s accounting provisions.

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

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. See the section entitled, “Business — Government Regulation — Current and future healthcare reform legislation” in our Annual Report on Form 10-K for the year ended December 31, 2021.

Patients who are provided medical treatment for their conditions 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 commercialize any products successfully, if approved, 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. 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 Patient Protection and Affordable Care Act, or the ACA, was passed, which substantially changes the way healthcare is financed by both governmental and private insurers, and significantly impacts the U.S. pharmaceutical industry.

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On August 16, 2022, the Inflation Reduction Act of 2022 was passed, which among other things, allows for CMS to negotiate prices for certain single-source drugs and biologics reimbursed under Medicare Part B and Part D, beginning with ten high-cost drugs paid for by Medicare Part D starting in 2026, followed by 15 Part D drugs in 2027, 15 Part B or Part D drugs in 2028, and 20 Part B or Part D drugs in 2029 and beyond. The legislation subjects drug manufacturers to civil monetary penalties and a potential excise tax for failing to comply with the legislation by offering a price that is not equal to or less than the negotiated “maximum fair price” under the law or for taking price increases that exceed inflation. The legislation also requires manufacturers to pay rebates for drugs in Medicare Part D whose price increases exceed inflation. Further, the legislation caps Medicare beneficiaries’ annual out-of-pocket drug expenses at $2,000. The effect of Inflation Reduction Act of 2022 on our business and the healthcare industry in general is not yet known.

Moreover, increasing efforts by governmental and third-party payors in the United States and abroad to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our product candidates. 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 and enacted 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.

These laws, and future state and federal healthcare reform measures may be adopted in the future, any of which may result in additional reductions in Medicare and other healthcare funding and otherwise affect the prices we may obtain for any of our product candidates for which we may obtain regulatory approval or the frequency with which any such product candidate is prescribed or used.

Risks related to our intellectual property

If we are unable to obtain and maintain patent protection for any product candidates we may develop or for our next generation red blood cell platform, our competitors could develop and commercialize products or technology similar or identical to ours, and our ability to successfully commercialize any product candidates we may develop, and our technology may be adversely affected.

Our success depends in large part on our ability to obtain and maintain patent protection in the United States and other countries with respect to the product candidates, next generation red blood cell platform and other technologies we may develop. We seek to protect our proprietary position by in-licensing intellectual property and filing patent applications in the United States and abroad relating to our potential product candidates and red blood cell platform, as well as other technologies that are important to our business. Given that the development of our technology and potential product candidates is at an early stage, our intellectual property portfolio with respect to certain aspects of our technology and potential product candidates is also at an early stage. For example, although we own issued patents related to our discontinued product candidates RTX-240 and RTX-224, there can be no assurance that we will secure issued patents for additional product candidates we may develop. We have filed or intend to file patent applications directed to the composition of matter of our potential product candidates and various processes of our red blood cell platform; however, there can be no assurance that any such patent applications will issue as granted patents. Furthermore, in some cases, we have only filed provisional patent applications on certain aspects of our technology and potential product candidates and each of these provisional patent applications is not eligible to become an issued patent until, among other things, we file a non-provisional patent application within 12 months of the filing date of the applicable provisional patent application. Any failure to file a non-provisional patent application within this timeline could cause us to lose the ability to obtain patent protection for the inventions disclosed in the associated provisional patent applications.

Composition of matter patents for biological and pharmaceutical products are generally considered to be the strongest form of intellectual property protection for those types of products, as such patents provide protection without regard to any method of use. Although we have secured issued United States composition of matter patents related to our discontinued product candidates RTX-240 and RTX-224, we cannot be certain that the claims in our pending patent applications covering the composition of matter of our potential product candidates will be considered patentable by the United States Patent and Trademark Office, or the USPTO, or by patent offices in foreign countries, or that the claims in any of our issued patents will be considered valid and enforceable by courts in the United States or foreign countries. Furthermore, in some cases, we may not be able to obtain issued claims covering compositions of matter relating to the product candidates we may develop, our red blood cell platform or the other technologies that are important to our business, and instead may need to rely on filing patent applications with claims covering a method of use and/or method of manufacture. Method of use patents protect the use of a product for the specified method. This type of patent does not prevent a competitor from making and marketing a product that is identical to our product for an indication that is outside the scope of the patented method. Moreover, even if competitors do not actively promote their products for our targeted indications, physicians may

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prescribe these products “off-label” for those uses that are covered by our method of use patents. Although off-label prescriptions may infringe or contribute to the infringement of method of use patents, the practice is common and such infringement is difficult to prevent or prosecute. There can be no assurance that any such patent applications will issue as granted patents, and even if they do issue, such patent claims may be insufficient to prevent third parties, such as our competitors, from utilizing our technology. Any failure to obtain or maintain patent protection with respect to any product candidates we may develop or for our next generation red blood cell platform could have a material adverse effect on our business, financial condition, results of operations, and prospects.

The patent position of biotechnology and pharmaceutical companies generally is highly uncertain and involves complex legal and factual questions for which legal principles remain unsolved. The patent applications that we own or in-license may fail to result in issued patents with claims that cover our future product candidates in the United States or in other foreign countries. There is no assurance that all potentially relevant prior art relating to our patents and patents applications has been found, which can invalidate a patent or prevent a patent from issuing from a pending patent application. Even if patents successfully issue, and even if such patents cover the product candidates we may develop, third parties may challenge their validity, enforceability, or scope, which may result in such patents being narrowed, found unenforceable or invalidated. Furthermore, even if they are unchallenged, our patents and patent applications may not adequately protect our intellectual property, provide exclusivity for the product candidates we may develop, or prevent others from designing around our claims. Any of these outcomes could impair our ability to prevent competition from third parties, which may have an adverse impact on our business.

We intend to rely on patent and other rights and available regulatory exclusivities, including the status of our future product candidates, if approved, as products eligible for reference product exclusivity under the BPCIA. If we are unable to obtain or maintain exclusivity from the combination of these approaches, we may not be able to compete effectively in our markets.

We rely or will rely upon a combination of patents, trade secret protection, confidentiality agreements and regulatory exclusivity to protect the intellectual property related to our technologies, pipeline products and any product candidates we may develop in the future. Our success depends in large part on our and our licensors’ ability to maintain patent and other intellectual property protection and obtain regulatory exclusivity in the United States and in other countries with respect to our proprietary technology and products.

Even if we cannot obtain and maintain effective protection of exclusivity from our intellectual property rights and regulatory efforts, including patent protection, data exclusivity or orphan drug exclusivity for any product candidates we may develop, we believe that our future product candidates could be protected, if approved, by reference product exclusivity under the BPCIA that prevents approval of a biosimilar product in the United States for a period of twelve years from the time the product to which it claims similarity was first approved. However, the BPCIA created an elaborate and complex patent dispute resolution mechanism for biosimilar applicants that poses a risk that patent infringement litigation may disrupt our activities and add increased expenses, as well as divert management’s attention. If a biosimilar version of one of our future product candidates were approved in the United States, it could have a negative effect on our business.

If any of our owned or in-licensed patent applications do not issue as patents in any jurisdiction, we may not be able to compete effectively.

With respect to our patent portfolio, as of September 30, 2022, most of the patent rights that we own or in-license are currently pending patent applications, except that we own 14 issued U.S. patents and we have four in-licensed U.S. patents. With respect to both in-licensed and owned intellectual property, we cannot predict whether the patent applications we and our licensors are currently pursuing will issue as patents in any particular jurisdiction or whether the claims of any issued patents will provide sufficient protection from competitors or other third parties.

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 patents and patent applications at a reasonable cost or in a timely manner. It is also possible that we will fail to identify patentable aspects of our research and development output in time to obtain patent protection. 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, corporate collaborators, outside scientific collaborators, contract research organizations, contract manufacturers, consultants, advisors and other third parties, any of these parties may breach such agreements and disclose such output before a patent application is filed, thereby jeopardizing our ability to seek patent protection. In addition, our ability to obtain and maintain valid and enforceable patents depends on whether the differences between our inventions and the prior art allow our inventions to be patentable over the prior art. Furthermore, 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. Therefore, we cannot be certain that we or our licensors were the

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first to make the inventions claimed in any of our owned or licensed patents or pending patent applications, or that we or our licensors were the first to file for patent protection of such inventions.

If the scope of any patent protection we obtain is not sufficiently broad, or if we lose any of our patent protection, our ability to prevent our competitors from commercializing similar or identical technology and product candidates would be adversely affected.

The patent position of biotechnology and pharmaceutical companies generally is highly uncertain, involves complex legal and factual questions, and has been the subject of much litigation in recent years. As a result, the issuance, scope, validity, enforceability, and commercial value of our patent rights are highly uncertain. Our owned or in-licensed pending and future patent applications may not result in patents being issued which protect any product candidates we may develop, our red blood cell platform technology, or other technologies or which effectively prevent others from commercializing competitive technologies and product candidates.

No consistent policy regarding the scope of claims allowable in patents in the biotechnology field has emerged in the United States. The patent situation outside of the United States is even more uncertain. Changes in either the patent laws or their interpretation in the United States and other countries may diminish our ability to protect our inventions and enforce our intellectual property rights, and more generally could affect the value of our intellectual property or narrow the scope of our owned or licensed patents. In particular, our ability to stop third parties from making, using, selling, offering to sell, or importing products that infringe our intellectual property will depend in part on our success in obtaining and enforcing patent claims that cover our technology, inventions and improvements. With respect to both licensed and company-owned intellectual property, we cannot be sure that patents will be granted with respect to any of our pending patent applications or with respect to any patent applications filed by us in the future, nor can we be sure that any of our existing patents or any patents that may be granted to us in the future will be commercially useful in protecting our products, the use of our products, and the methods used to manufacture those products. Moreover, even our issued patents do not guarantee us the right to practice our technology in relation to the commercialization of our products. The area of patent and other intellectual property rights in biotechnology is an evolving one with many risks and uncertainties, and third parties may have blocking patents that could be used to prevent us from commercializing any patented product candidates we may develop and practicing our proprietary technology. Our issued patents and those that may issue in the future may be challenged, invalidated, or circumvented, which could limit our ability to stop competitors from marketing related products or limit the length of the term of patent protection that we may have for our future product candidates. In addition, the rights granted under any issued patents may not provide us with protection or competitive advantages against competitors with similar technology. Furthermore, our competitors may independently develop similar technologies. For these reasons, we may have competition for our future product candidates. Moreover, because of the extensive time required for development, testing and regulatory review of a potential product, it is possible that, before any particular product candidate can be commercialized, any related patent may expire or remain in force for only a short period following commercialization, thereby reducing any advantage of the patent.

In addition, the coverage claimed in a patent application can be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. Even if patent applications we own or license issue as patents, they may not issue in a form that will provide us with any meaningful protection, prevent competitors or other third parties from competing with us, or otherwise provide us with any competitive advantage. Any patents that we own or in-license may be challenged, narrowed, circumvented, or invalidated by third parties. Consequently, we do not know whether our future product candidates, red blood cell platform technologies or other technologies will be protectable or remain protected by valid and enforceable patents. Our competitors or other third parties may be able to circumvent our patents by developing similar or alternative technologies or products in a non-infringing manner which could materially adversely affect our business, financial condition, results of operations and prospects.

The issuance of a patent is not conclusive as to its inventorship, scope, validity, or enforceability, and patents that we own or license may be challenged in the courts or patent offices in the U.S. and abroad. We or our licensors may be subject to a third-party pre-issuance submission of prior art to the USPTO or to foreign patent authorities or become involved in opposition, derivation, revocation, reexamination, post-grant and inter partes review, or interference proceedings or other similar proceedings challenging our owned or licensed patent rights. An adverse determination in any such submission, proceeding or litigation could reduce the scope of, or invalidate or render unenforceable, our owned or in-licensed patent rights, allow third parties to commercialize our future product candidates, red blood cell platform technologies or other technologies and compete directly with us, without payment to us, or result in our inability to manufacture or commercialize products without infringing third-party patent rights. Moreover, we, or one of our licensors, may have to participate in interference proceedings declared by the USPTO to determine priority of invention or in post-grant challenge proceedings, such as oppositions in a foreign patent office, which challenge our or our licensor’s priority of invention or other features of patentability with respect to our owned or in-licensed patents and patent applications. Such challenges may result in loss of patent rights, loss of exclusivity, or in patent claims being narrowed, invalidated, or held

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unenforceable, which could limit our ability to stop others from using or commercializing similar or identical technology and products, or limit the duration of the patent protection of our future product candidates, red blood cell platform technology and other technologies. Such proceedings also may result in substantial cost and require significant time from our scientists and management, even if the eventual outcome is favorable to us.

In addition, given the amount of time required for the development, testing, and regulatory review of new product candidates, patents protecting such product candidates might expire before or shortly after such product candidates are commercialized. As a result, our intellectual property may not provide us with sufficient rights to exclude others from commercializing products similar or identical to ours.

We may, in the future, co-own patent rights relating to future product candidates and our next generation red blood cell platform with third parties. Some of our in-licensed patent rights are, and may in the future be, co-owned with third parties. In addition, our licensors may co-own the patent rights we in-license with other third parties with whom we do not have a direct relationship. Our exclusive rights to certain of these patent rights are dependent, in part, on inter-institutional or other operating agreements between the joint owners of such patent rights, who are not parties to our license agreements. For example, under our license agreement with the Whitehead Institute for Biomedical Research, or WIBR, as amended (or the WIBR License) we license certain patents rights co-owned by WIBR and Tufts University, or Tufts. Our rights to Tufts’ interest in such patent rights depends on an inter-institutional agreement between WIBR and Tufts, pursuant to which WIBR controls the licensing of such patent rights. If our licensors do not have exclusive control of the grant of licenses under any such third-party co-owners’ interest in such patent rights or we are otherwise unable to secure such exclusive rights, such co-owners may be able to license their rights to other third parties, including our competitors, and our competitors could market competing products and technology. In addition, we may need the cooperation of any such co-owners of our patent rights in order to enforce such patent rights against third parties, and such cooperation may not be provided to us. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations, and prospects.

Our rights to develop and commercialize our product candidates and our next generation red blood cell platform are subject, in part, to the terms and conditions of licenses granted to us by others.

We rely upon licenses to certain patent rights and proprietary technology from third parties that are important or necessary to the development of our product candidates and red blood cell platform. For example, under the WIBR License, WIBR grants us an exclusive, worldwide, sublicensable license under four patent families to research, develop, make, and commercialize products and processes covered by such patent rights for all uses. The portfolio of patent rights licensed to us under the WIBR License is directed, in part, to the in vitro production of red blood cells, including the use of the enzyme sortase to conjugate a protein of interest to the cell surface. Patent rights that we in-license may be subject to a reservation of rights by one or more third parties. For example, our in-licensed patent rights from WIBR under the WIBR License were funded in part by the U.S. government. As a result, the U.S. government may have certain rights to such intellectual property. Furthermore, pursuant to a Defense Advanced Research Projects Agency Agreement between WIBR and a global biopharmaceutical company, the biopharmaceutical company funded research resulting in one of the patent families licensed to us under the WIBR License and retained a worldwide, irrevocable, non-exclusive, royalty-free right to use the inventions and technologies covered by this patent family for research and development purposes. WIBR also retains the right with respect to all four patent families licensed to us to (i) to practice the patent rights licensed under the agreement for research, teaching and educational purposes, including sponsored research and collaboration, and (ii) to grant non-exclusive licenses to academic and not-for-profit research institutes to practice under the patent rights for research, teaching and educational purposes (excluding sponsored research), while Tufts retains such rights only with respect to the patent family that it co-owns.

In addition, subject to the terms of any such license agreements, we may not have the right to control the preparation, filing, prosecution and maintenance, and we may not have the right to control the enforcement, and defense of patents and patent applications covering the technology that we license from third parties. For example, under the WIBR License, WIBR controls prosecution of the patent rights licensed to us, and we control enforcement of the patent rights. We cannot be certain that our in-licensed patent applications (and any patents issuing therefrom) that are controlled by our licensors will be prepared, filed, prosecuted, maintained, enforced, and defended in a manner consistent with the best interests of our business. If our licensors fail to prosecute, maintain, enforce, and defend such patents rights, or lose rights to those patent applications (or any patents issuing therefrom), the rights we have licensed may be reduced or eliminated, our right to develop and commercialize any of our product candidates and red blood cell platform technologies that are the subject of such licensed rights could be adversely affected, and we may not be able to prevent competitors from making, using and selling competing products. Moreover, we cannot be certain that such activities by our licensors have been or will be conducted in compliance with applicable laws and regulations or will result in valid and enforceable patents or other intellectual property rights. In addition, even where we have the right to control patent prosecution of patents and patent applications, we have licensed from third parties, we may still be adversely affected or prejudiced by actions or inactions of

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our licensors and their counsel that took place prior to the date upon which we assumed control over patent prosecution. Finally, subject to the terms of any such license agreements, the licensor may be able to terminate the license without our consent. For example, under the WIBR License, WIBR may terminate the WIBR License upon written notice to us if we, along with our affiliates and sublicensees, cease to carry on business related to the WIBR License for more than six months. WIBR may also terminate the WIBR License for our material breach that remains uncured for sixty days after receiving notice thereof, if we fail to pay amounts due under the agreement within thirty days after receiving notice of such failure, or if we challenge the validity or enforceability of any of the licensed patent rights.

Some intellectual property may have been discovered through government funded programs and thus may be subject to federal regulations such as “march-in” rights, certain reporting requirements and a preference for U.S.-based companies. Compliance with such regulations may limit our exclusive rights and limit our ability to contract with non-U.S. manufacturers.

Our in-licensed patent rights from WIBR under the WIBR License were funded in part by the U.S. government and are therefore subject to certain federal regulations. When new technologies are developed with U.S. government funding, the U.S. government generally obtains certain rights in any resulting patents, including rights to disclose the funded inventions and technology to third parties and to exercise march-in rights to use or allow third parties to use the technology we have licensed that was developed using U.S. government funding. The U.S. government may exercise its march-in rights if it determines that action is necessary because we fail to achieve practical application of the government-funded technology, or because action is necessary to alleviate health or safety needs, to meet requirements of federal regulations, or to give preference to U.S. industry. In addition, our rights in such inventions may be subject to certain requirements to manufacture products embodying such inventions in the United States in certain circumstances and if this requirement is not waived. Any exercise by the U.S. government of such rights or by any third party of its reserved rights could have a material adverse effect on our competitive position, business, financial condition, results of operations, and prospects.

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

The WIBR License imposes, and we expect our future license agreements will impose, various development, diligence, commercialization, and other obligations on us in order to maintain the licenses. In spite of our efforts, WIBR or a future licensor might conclude that we have materially breached our obligations under such license agreements and seek 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 patent rights licensed thereunder fail to provide the intended exclusivity, competitors or other third parties would 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 certain of our pipeline products, future product candidates, or of our red blood cell platform technologies. 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 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 partners;

•whether and the extent to which inventors are able to contest the assignment of their rights to our licensors; and

•the priority of invention of patented technology.

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

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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 continue to utilize our red blood cell platform or 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.

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

Filing, prosecuting, and defending patents on our pipeline products, future product candidates, red blood cell platform technologies, and other technologies essential to our business operations, in all countries throughout the world would be prohibitively expensive, and the laws of foreign countries may not protect our rights to the same extent as the laws of 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 their own products and, further, may export otherwise infringing products to territories where we have patent protection, but enforcement is not as strong as that in the United States. These products may compete with our products, and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents, trade secrets, and other intellectual property protection, particularly those relating to biotechnology products, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our intellectual property and proprietary rights generally. Proceedings to enforce our intellectual property and proprietary rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly, could put 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 enforce our intellectual property and proprietary rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license.

Many countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties. In addition, 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 patents. If we or any of our licensors is 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, financial condition, results of operations, and prospects may be adversely affected.

Our inability to protect our intellectual property or failure to maintain the confidentiality and integrity of data or other sensitive company information could have a material adverse effect on our business.

Our success and competitive position are dependent in part upon our proprietary intellectual property. We rely on a combination of patents and trade secrets to protect our proprietary intellectual property, and we expect to continue to do so. Although we seek to protect our proprietary rights through a variety of means, we cannot guarantee that the protective steps we have taken are adequate to protect these rights. Patents issued to or licensed by us in the past or in the future may be challenged and held invalid. In addition, as our patents expire, we may be unsuccessful in extending their protection through patent term extensions. The expiration of, or the failure to maintain or extend our patents, could have a material adverse effect on us.

We also rely on confidentiality agreements with certain employees, consultants, and other third parties to protect, in part, trade secrets and other proprietary information. These agreements could be breached, and we may not have adequate remedies for such a breach. In addition, others could independently develop substantially equivalent proprietary information or gain access to our trade secrets or proprietary information.

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

Periodic maintenance fees, renewal fees, annuity fees, and various other government fees on patents and applications will be due to be paid to the USPTO and various government patent agencies outside of the United States over the lifetime of our owned or licensed patents and applications. In certain circumstances, we rely on our licensing partners to pay these fees

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due to U.S. and non-U.S. patent agencies. The USPTO and various non-U.S. government agencies require compliance with several procedural, documentary, fee payment, and other similar provisions during the patent application process. We are also dependent on our licensors to take the necessary action to comply with these requirements with respect to our licensed intellectual property. In some cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with the applicable rules. There are situations, however, in which non-compliance can result in abandonment or lapse of the patent or patent application, resulting in a partial or complete loss of patent rights in the relevant jurisdiction. In such an event, potential competitors might be able to enter the market with similar or identical products or technology, which could have a material adverse effect on our business, financial condition, results of operations, and prospects.

Changes in U.S. patent law could diminish the value of patents in general, thereby impairing our ability to protect our products.

Changes in either the patent laws or interpretation of the patent laws in the United States could increase the uncertainties and costs surrounding the prosecution of patent applications and the enforcement or defense of issued patents. Assuming that other requirements for patentability are met, prior to March 2013, in the United States, the first to invent the claimed invention was entitled to the patent, while outside the United States, the first to file a patent application was entitled to the patent. After March 2013, under the Leahy-Smith America Invents Act, or the America Invents Act, enacted in September 2011, the United States transitioned to a first inventor to file system in which, assuming that other requirements for patentability 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. A third party that files a patent application in the USPTO after March 2013, but before us, could therefore be awarded a patent covering an invention of ours even if we had made the invention before it was made by such third party. This will require us to be cognizant going forward of the time from invention to filing of a patent application. Since patent applications in the United States and most other countries are confidential for a period of time after filing or until issuance, we cannot be certain that we or our licensors were the first to either (i) file any patent application related to our pipeline products, any future product candidates, our next generation red blood cell platform or other technologies or (ii) invent any of the inventions claimed in our or our licensor’s patents or patent applications.

The America Invents Act also includes a number of significant changes that affect the way patent applications will be prosecuted and also may affect patent litigation. These 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. Because of a lower evidentiary standard in USPTO proceedings compared to the evidentiary standard in United States federal courts necessary to invalidate a patent claim, a third party could potentially provide evidence in a USPTO proceeding sufficient for the USPTO to hold a claim invalid even though the same evidence would be insufficient to invalidate the claim if first presented in a district court action. Accordingly, a third party may attempt to use the USPTO procedures to invalidate our patent claims that would not have been invalidated if first challenged by the third party as a defendant in a district court action. Therefore, the America Invents Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our owned or in-licensed patent applications and the enforcement or defense of our owned or in-licensed issued patents, all of which could have a material adverse effect on our business, financial condition, results of operations, and prospects.

In addition, the patent positions of companies in the development and commercialization of biologics and pharmaceuticals are particularly uncertain. Recent U.S. Supreme Court rulings have narrowed the scope of patent protection available in certain circumstances and weakened the rights of patent owners in certain situations. This combination of events has created uncertainty with respect to the validity and enforceability of patents, once obtained. Depending on future actions by the U.S. Congress, the federal courts, and the USPTO, the laws and regulations governing patents could change in unpredictable ways that could have a material adverse effect on our existing patent portfolio and our ability to protect and enforce our intellectual property in the future.

Issued patents covering our pipeline products, future product candidates, and any patents that may be issued covering our red blood cell platform technologies and other technologies, could be found invalid or unenforceable if challenged in court or before administrative bodies in the United States or abroad.

If we or one of our licensors initiated legal proceedings against a third party to enforce a patent covering our pipeline products, future product candidates, red blood cell platform technologies or other technologies, the defendant could counterclaim that such patent is invalid or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity or unenforceability are commonplace. Grounds for a validity challenge could be 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 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 raise claims

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challenging the validity or enforceability of our owned or in-licensed patents before administrative bodies in the United States or abroad, even outside the context of litigation. Such mechanisms include re-examination, post-grant review, inter partes review, interference proceedings, derivation proceedings, and equivalent proceedings in foreign jurisdictions (e.g., opposition proceedings). Such proceedings could result in the revocation of, cancellation of, or amendment to our patents in such a way that they no longer cover our pipeline products, future product candidates, red blood cell platform technologies, or other technologies. The outcome following legal assertions of invalidity and unenforceability is unpredictable. With respect to the validity question, for example, we cannot be certain that there is no invalidating prior art, of which we or our licensing partners 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 our pipeline products, future product candidates, red blood cell platform or other technologies. Such a loss of patent protection would have a material adverse impact on our business, financial condition, results of operations, and prospects.

If we do not obtain patent term extension and/or data exclusivity for any product candidates we may develop, our business may be materially harmed.

Depending upon the timing, duration and specifics of any FDA marketing approval of any product candidates we may develop, one or more of our owned or in-licensed U.S. patents may be eligible for limited patent term extension under the Hatch-Waxman Act. The Hatch-Waxman Act permits a patent term extension of up to five years as compensation for patent term lost during the FDA regulatory review process. A patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval, only one patent may be extended and only those claims covering the approved drug, a method for using it, or a method for manufacturing it may be extended. Similar extensions as compensation for patent term lost during regulatory review processes are also available in certain foreign countries and territories, such as in Europe under a Supplementary Protection Certificate. However, we may not be granted an extension in the United States and/or foreign countries and territories because of, for example, failing to exercise due diligence during the testing phase or regulatory review process, failing to apply within applicable deadlines, failing to apply prior to expiration of relevant patents, or otherwise failing to satisfy applicable requirements. Moreover, the applicable time period or the scope of patent protection afforded could be less than we request. If we are unable to obtain patent term extension or the term of any such extension is shorter than what we request, our competitors may obtain approval of competing products following our patent expiration, and our business, financial condition, results of operations and prospects could be materially harmed.

We may be subject to claims challenging the inventorship of our patents and other intellectual property.

We or our licensors may be subject to claims that former employees, collaborators or other third parties have an interest in our owned or in-licensed patent rights, trade secrets, or other intellectual property as an inventor or co-inventor. For example, we or our licensors may have inventorship disputes arise from conflicting obligations of employees, consultants or others who are involved in developing our pipeline products, future product candidates, our next generation red blood cell platform or other technologies. Litigation may be necessary to defend against these and other claims challenging inventorship or our licensors’ ownership of our owned or in-licensed patent rights, trade secrets or other intellectual property. If we or our licensors fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, intellectual property that is important to our pipeline products, future product candidates, red blood cell platform and other technologies. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees. Any of the foregoing could have a material adverse effect on our business, financial condition, results of operations and prospects.

If we are unable to protect the confidentiality of our trade secrets, our business and competitive position would be harmed.

In addition to seeking patents for our pipeline products, future product candidates, next generation red blood cell platform and other technologies, we also rely on trade secrets and confidentiality agreements to protect our unpatented know-how, technology, and other proprietary information and to maintain our competitive position. Trade secrets and know-how can be difficult to protect. We expect our trade secrets and know-how to over time be disseminated within the industry through independent development, the publication of journal articles describing the methodology, and the movement of personnel from academic to industry scientific positions.

We currently, and may continue in the future continue to, rely on third parties to assist us in developing and manufacturing our product candidates. Accordingly, we must, at times, share know-how and trade secrets, including those related to our red blood cell platform, with them. We may in the future also enter into research and development collaborations with third parties that may require us to share know-how and trade secrets under the terms of our research and development

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partnerships or similar agreements. We seek to protect our know-how, trade secrets and other proprietary technology, in part, by entering into non-disclosure and confidentiality agreements, and including in our vendor and service agreements terms protecting our confidential information, know-how and trade secrets, with parties who have access to such information, such as our employees, scientific collaborators, contract research organizations, contract manufacturers, consultants, advisors and other third parties. We also enter into confidentiality and invention or patent assignment agreements with our employees and consultants, as well as train our employees not to bring or use proprietary information or technology from former employers to us or in their work, and we remind former employees when they leave their employment of their confidentiality obligations. However, we cannot guarantee that we have entered into such agreements with each party that may have or have had access to our trade secrets or proprietary technology and processes. We also seek to preserve the integrity and confidentiality of our data and other confidential information by maintaining physical security of our premises and physical and electronic security of our information technology systems.

Despite our efforts, any of the aforementioned parties may breach the agreements and disclose our proprietary information, including our trade secrets, or there may be a lapses or failures in our physical and electronic security systems which lead to our proprietary information being disclosed, and we may not be able to obtain adequate remedies in the event of any such breaches. Monitoring unauthorized uses and disclosures is difficult, and we do not know whether the steps we have taken to protect our proprietary technologies will be effective. If any of our scientific advisors, employees, contractors and consultants who are parties to these agreements breaches or violates the terms of any of these agreements, we may not have adequate remedies for any such breach or violation, and we could lose our trade secrets as a result. Moreover, if confidential information that is licensed or disclosed to us by our partners, collaborators, or others is inadvertently disclosed or subject to a breach or violation, we may be exposed to liability to the owner of that confidential information. 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 inside and outside 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. If any of our trade secrets were to be disclosed to or independently developed by a competitor or other third party, our competitive position would be materially and adversely harmed.

We may not be successful in obtaining, through acquisitions, in-licenses or otherwise, necessary rights to any product candidates, red blood cell platform technologies or other technologies we may develop.

We currently have rights to certain intellectual property, through licenses from third parties, to develop our potential product candidates and red blood cell platform technologies. Some pharmaceutical companies, biotechnology companies, and academic institutions are competing with us in the field of cellular therapeutics and red blood cell technologies and may have patents and have filed and are likely filing patent applications potentially relevant to our business. In order to avoid infringing these third-party patents, we may find it necessary or prudent to obtain licenses to such patents from such third-party intellectual property holders. We may also require licenses from third parties for certain technologies that we are evaluating for use with our pipeline products or future product candidates. However, we may be unable to secure such licenses or otherwise acquire or in-license any compositions, methods of use, processes, or other intellectual property rights from third parties that we identify as necessary for the product candidates we have been developing or our next generation red blood cell platform at a reasonable cost or on reasonable terms, if at all. The licensing or acquisition of third-party intellectual property rights is a competitive area, and several more established companies may pursue strategies to license or acquire third-party intellectual property rights that we may consider attractive or necessary. These established companies may have a competitive advantage over us due to their size, capital resources and greater clinical development and commercialization capabilities. In addition, companies that perceive us to be a competitor may be unwilling to assign or license rights to us. We also may be unable to license or acquire third-party intellectual property rights on terms that would allow us to make an appropriate return on our investment or at all.

If we are unable to successfully obtain rights to required third-party intellectual property rights or maintain the existing intellectual property rights we have, we may be required to expend significant time and resources to redesign our technology, product candidates, or the methods for manufacturing them or to develop or license replacement technology, all of which may not be feasible on a technical or commercial basis. If we are unable to do so, we may be unable to develop or commercialize the affected product candidates or continue to utilize our existing red blood cell platform technology, which could harm our business, financial condition, results of operations, and prospects significantly.

We may be subject to claims that our employees, consultants, or advisors have wrongfully used or disclosed alleged trade secrets of their current or former employers or claims asserting ownership of what we regard as our own intellectual property.

Many of our employees, consultants, and advisors are currently or were previously employed at universities or other biotechnology or pharmaceutical companies, including our licensors, competitors and potential competitors. Although we

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try to ensure that our employees, consultants, and advisors do not use the proprietary information or know-how of others in their work for us, we may be subject to claims that we or these individuals have used 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 these claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management.

In addition, while it is our policy to require our employees and contractors who may be involved in the conception or development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who, in fact, conceives or develops intellectual property that we regard as our own. 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 against third parties, or defend claims that they may bring against us, to determine the ownership of what we regard as our intellectual property. Such claims could have a material adverse effect on our business, financial condition, results of operations, and prospects.

Third-party claims of intellectual property infringement, misappropriation or other violation against us, our licensors or our collaborators may prevent or delay the development and commercialization of our product candidates, our next generation red blood cell platform and other technologies.

The field of cellular therapeutics is competitive and dynamic. Due to the focused research and development that is taking place by several companies, including us and our competitors, in this field, the intellectual property landscape is in flux, and it may remain uncertain in the future. As such, there may be significant intellectual property related litigation and proceedings relating to our owned and in-licensed, and other third-party, intellectual property and proprietary rights in the future.

Our commercial success depends in part on our, our licensors’ and our collaborators’ ability to avoid infringing, misappropriating and otherwise violating the patents and other intellectual property rights of third parties. There is a substantial amount of complex litigation involving patents and other intellectual property rights in the biotechnology and pharmaceutical industries, as well as administrative proceedings for challenging patents, including interference, derivation and reexamination proceedings before the USPTO or oppositions and other comparable proceedings in foreign jurisdictions. As discussed above, recently, due to changes in U.S. law referred to as patent reform, new procedures including inter partes review and post-grant review have been implemented. As stated above, this reform adds uncertainty to the possibility of challenge to our patents in the future.

Numerous U.S. and foreign issued patents and pending patent applications owned by third parties exist relating to red blood cell technologies and therapeutic proteins, and in the fields in which we have been developing our product candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, the risk increases that our pipeline products, future product candidates, red blood cell platform technologies and other technologies may give rise to claims of infringement of the patent rights of others. We cannot assure you that our product candidates, red blood cell platform technologies and other technologies that we have developed, are developing or may develop in the future will not infringe existing or future patents owned by third parties. We may not be aware of patents that have already been issued and that a third party, for example, a competitor in the fields in which we have been developing our product candidates, red blood cell platform and other technologies might assert are infringed by our pipeline products, future product candidates, red blood cell platform or other technologies, including claims to compositions, formulations, methods of manufacture or methods of use or treatment that cover our pipeline products, future product candidates, red blood cell platform or other technologies.

It is also possible that patents owned by third parties of which we are aware, but which we do not believe are relevant to our pipeline products, future product candidates, red blood cell platform or other technologies, could be found to be infringed by our pipeline products, future product candidates, red blood cell platform or other technologies. In addition, because patent applications can take many years to issue, there may be currently pending patent applications that may later result in issued patents that our pipeline products, future product candidates, red blood cell platform or other technologies may infringe. We cannot provide any assurances that third-party patents do not exist which might be enforced against our current technology, including our red blood cell platform technologies, manufacturing methods, pipeline products, future product candidates, or future methods or products resulting in either an injunction prohibiting our manufacture or future sales, or, with respect to our future sales, an obligation on our part to pay royalties and/or other forms of compensation to third parties, which could be significant.

Third parties may have patents or obtain patents in the future and claim that the manufacture, use or sale of our product candidates, red blood cell platform or other technologies infringes upon these patents. We are aware of an issued patent outside the United States that is directed to erythrocytes that comprise exogeneous polypeptides. While we believe that we

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have reasonable defenses against a claim of infringement should such a claim be brought, including that certain claims in this patent are invalid, there can be no assurance that we will prevail in any such action by the holder of the patent. In the event that any third-party claims that we infringe their patents or that we are otherwise employing their proprietary technology without authorization and initiates litigation against us, even if we believe such claims are without merit, a court of competent jurisdiction could hold that such patents are valid, enforceable and infringed by any product candidates, red blood cell platform or other technologies we may develop. In this case, the holders of such patents may be able to block our ability to commercialize the applicable product candidate or technology unless we obtain a license under the applicable patents, or until such patents expire or are finally determined to be held invalid or unenforceable. Such a license may not be available on commercially reasonable terms or at all. Even if we are able to obtain a license, the license would likely obligate us to pay license fees or royalties or both, and the rights granted to us might be non-exclusive, which could result in our competitors gaining access to the same intellectual property. If we are unable to obtain a necessary license to a third-party patent on commercially reasonable terms, we may be unable to commercialize our product candidates, red blood cell platform, or other technologies, or such commercialization efforts may be significantly delayed, which could in turn significantly harm our business.

Defense of infringement claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of management and other employee resources from our business, and may impact our reputation. In the event of a successful claim of infringement against us, we may be enjoined from further developing or commercializing our infringing product candidates, red blood cell platform, or other technologies. In addition, we may have to pay substantial damages, including treble damages and attorneys’ fees for willful infringement, obtain one or more licenses from third parties, pay royalties and/or redesign our infringing product candidates or technologies, which may be impossible or require substantial time and monetary expenditure. In that event, we would be unable to further develop and commercialize our product candidates, red blood cell platform, or other technologies, which could harm our business significantly.

Engaging in litigation to defend against third parties alleging that we have infringed, misappropriated or otherwise violated their patents or other intellectual property rights is very expensive, particularly for a company of our size, and time-consuming. Some of our competitors may be able to sustain the costs of litigation or administrative proceedings more effectively than we can because of greater financial resources. Patent litigation and other proceedings may also absorb significant management time. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings against us could impair our ability to compete in the marketplace. The occurrence of any of the foregoing could have a material adverse effect on our business, financial condition or results of operations.

If our trademarks and trade names are not adequately protected, then we may not be able to build name recognition in our markets of interest and our business may be adversely affected.

Our registered or unregistered trademarks or trade names may be challenged, infringed, circumvented or declared generic or determined to be infringing on other marks. We may not be able to protect our rights to these trademarks and trade names, which we need to build name recognition among potential partners or customers in our markets of interest. At times, competitors or other third parties may adopt trade names or trademarks similar to ours, thereby impeding our ability to build brand identity and possibly leading to market confusion. If we assert trademark infringement claims, a court may determine that the marks we have asserted are invalid or unenforceable, or that the party against whom we have asserted trademark infringement has superior rights to the marks in question. In this case, we could ultimately be forced to cease use of such trademarks. In addition, there could be potential trade name or trademark infringement claims brought by owners of other registered trademarks or trademarks that incorporate variations of our registered or unregistered trademarks or trade names. Over the long term, if we are unable to establish name recognition based on our trademarks and trade names, then we may not be able to compete effectively and our business may be adversely affected. Our efforts to enforce or protect our proprietary rights related to trademarks, trade secrets, domain names, copyrights or other intellectual property may be ineffective and could result in substantial costs and diversion of resources and could adversely affect our business, financial condition, results of operations and prospects.

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:

•others may be able to make products that are similar to our product candidates or utilize similar technology but that are not covered by the claims of the patents that we license or own;

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•we, or our current or future licensors or collaborators, might not have been the first to make the inventions covered by the issued patent or pending patent application that we license or own now or in the future;

•we, or our current or future licensors or 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 any of our technologies without infringing our owned or licensed intellectual property rights;

•it is possible that our current or future pending owned or licensed patent applications 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 or other third parties;

•our competitors or other third parties 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 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 and prospects.

Risks related to our reliance on third parties

We will rely on third parties to conduct our future clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines or comply with regulatory requirements, we may not be able to obtain regulatory approval of, or commercialize, any potential product candidates.

We have in the past depended, and expect to depend in the future, upon third parties, including independent investigators, to conduct our clinical trials under agreements with universities, medical institutions, CROs, strategic partners and others. In addition, we expect to rely on CROs to wind down our clinical trials of RTX-240 and RTX-224. We have in the past had to, and expect in the future to have to, negotiate budgets and contracts with CROs and trial sites, which may result in delays to our development timelines and increased costs.

We have in the past relied, and expect in the future to rely, heavily on third parties over the course of our clinical trials, and, as a result, will have limited control over the clinical investigators and limited visibility into their day-to-day activities, including with respect to their compliance with the approved clinical protocol. Nevertheless, we are responsible for ensuring that any trial we may conduct is conducted in accordance with the applicable protocol, legal and regulatory requirements and scientific standards, and our reliance on third parties does not relieve us of our regulatory responsibilities. We and these third parties will be required to comply with GCP requirements, which are regulations and guidelines enforced by the FDA and comparable foreign regulatory authorities for product candidates in clinical development. Regulatory authorities enforce these GCP requirements through periodic inspections of trial sponsors, clinical investigators and trial sites. If we or any of these third parties fail to comply with applicable GCP requirements, the clinical data generated in any future clinical trials we may conduct may be deemed unreliable and the FDA or comparable foreign regulatory authorities may require us to suspend or terminate these trials or perform additional nonclinical studies or clinical trials before approving our marketing applications. We cannot be certain that, upon inspection, such regulatory authorities will determine that any future clinical trials we may conduct comply with the GCP requirements. In addition, any clinical trials we conduct in the future will need to be conducted with biologic product produced under cGMP requirements and may require a large number of patients.

Our failure or any failure by these third parties to comply with applicable legal and regulatory requirements or to recruit a sufficient number of patients may require us to repeat clinical trials, which would delay the regulatory approval process. Moreover, our business may be implicated if any of these third parties violates federal or state fraud and abuse or false claims laws and regulations or healthcare privacy and security laws.

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Any third parties conducting our future clinical trials will not be our employees and, except for remedies that may be available to us under our agreements with such third parties, we cannot control whether or not they will devote sufficient time and resources to our future clinical programs. These third parties may also have relationships with other commercial entities, including our competitors, for whom they may also be conducting clinical trials or other product development activities, which could affect their performance on our behalf. If these third parties do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to our clinical protocols or regulatory requirements or for other reasons, our future clinical trials may be extended, delayed or terminated and we may not be able to complete development of, obtain regulatory approval of or successfully commercialize our future product candidates. As a result, our financial results and the commercial prospects for our future product candidates would be harmed, our costs could increase and our ability to generate revenue could be delayed.

If any of our relationships with these third-party CROs or others terminate, we may not be able to enter into arrangements with alternative CROs or other third parties or do so on commercially reasonable terms. Switching or adding CROs involves additional cost and requires management time and focus. In addition, there is a natural transition period when a new CRO begins work. As a result, delays may occur, which can materially impact our ability to meet our desired clinical development timelines. Though we plan to carefully manage our relationships with our CROs, there can be no assurance that we will not encounter similar challenges or delays in the future or that any such delays or challenges will not have a material adverse impact on our business, financial condition and prospects.

We may rely on third parties to conduct investigator-sponsored clinical trials of our future product candidates. Any failure by a third party to meet its obligations with respect to the clinical development of such product candidates may delay or impair our ability to obtain regulatory approval for such product candidates.

We may rely on academic and private non-academic institutions to conduct and sponsor clinical trials relating to our future product candidates. We will not control the design or conduct of the investigator-sponsored trials, and it is possible that the FDA or non-U.S. regulatory authorities will not view these investigator-sponsored trials as providing adequate support for future clinical trials, whether controlled by us or third parties, for any one or more reasons, including elements of the design or execution of the trials or safety concerns or other trial results.

Such arrangements will likely provide us certain information rights with respect to the investigator-sponsored trials, including access to and the ability to use and reference the data, including for our own regulatory filings, resulting from the investigator-sponsored trials. However, we would not have control over the timing and reporting of the data from investigator-sponsored trials, nor would we own the data from the investigator-sponsored trials. If we are unable to confirm or replicate the results from the investigator-sponsored trials or if negative results are obtained, we would likely be further delayed or prevented from advancing further clinical development of our future product candidates. Further, if investigators or institutions breach their obligations with respect to the clinical development of our future product candidates, or if the data proves to be inadequate compared to the first-hand knowledge we might have gained had the investigator-sponsored trials been sponsored and conducted by us, then our ability to design and conduct any future clinical trials ourselves may be adversely affected.

Additionally, the FDA or non-U.S. regulatory authorities may disagree with the sufficiency of our right of reference to the preclinical, manufacturing or clinical data generated by these investigator-sponsored trials, or our interpretation of preclinical, manufacturing or clinical data from these investigator-sponsored trials. If so, the FDA or other non-U.S. regulatory authorities may require us to obtain and submit additional preclinical, manufacturing, or clinical data before we may initiate any planned trials and/or may not accept such additional data as adequate to initiate such trials.

We may rely on third parties to produce and process any product candidates we may develop and/or our products, if approved.

We currently rely on outside vendors to supply raw materials and other important components, such as red blood cells and proteins, which are used in our preclinical studies and which will be used to manufacture any product candidates we may develop. We may not be able to manufacture sufficient materials to meet preclinical and clinical demand for our product candidates and may not reach commercial scale for any future product candidates for which we obtain regulatory approval. We will make changes as we work to optimize the manufacturing process for our potential product candidates, and we cannot be sure that even minor changes in the process will result in therapies that are safe and effective.

The facilities used to manufacture our product candidates must be approved by the FDA or other foreign regulatory agencies pursuant to inspections that will be conducted after we submit an application to the FDA or other foreign regulatory agencies. If we or any contract manufacturers that we may engage cannot successfully manufacture in conformance with our specifications and the strict regulatory requirements of the FDA or other regulatory authorities, we

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and they will not be able to secure and/or maintain regulatory approval for their manufacturing facilities with respect to the manufacture of any product candidate. In addition, we have no control over the ability of any contract manufacturers that we may engage to maintain adequate quality control, quality assurance and qualified personnel and such third parties may experience business interruptions. If the FDA or a comparable foreign regulatory authority does not approve these facilities for the manufacture of any product candidates we may develop 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 future product candidates, if approved.

For more information, see “Risk factors—Risks related to manufacturing and supply” below.

Cell therapies rely on the availability of specialty raw materials, which may not be available to us on acceptable terms or at all.

Our potential product candidates require certain specialty raw materials, some of which we obtain from small companies with limited resources and experience to support a clinical or commercial product. In addition, those suppliers normally support blood-based hospital businesses and generally do not have the capacity to support clinical or commercial products manufactured under cGMP by biopharmaceutical firms. The suppliers may be ill-equipped to support our needs, especially in non-routine circumstances like an FDA inspection or medical crisis, such as widespread contamination. We do not currently have contracts in place with all of the suppliers that we may need at any point in time, and if needed, may not be able to contract with them on acceptable terms or at all. Accordingly, we may experience delays in receiving key raw materials to support future clinical or commercial manufacturing.

We will depend on suppliers for red blood cells and some of the other components and materials used to manufacture our future product candidates.

We will depend on suppliers for red blood cells and some of the other components and materials necessary to manufacture our future product candidates and our suppliers of red blood cells depend on the availability of human donors. We cannot be sure that these suppliers will remain in business, that they will be able to identify and recruit adequate numbers of donors, that they will be able to meet our supply needs, that they will not be purchased by one of our competitors or another company that is not interested in continuing to produce these materials for our intended purpose or whether they will otherwise be affected by factors outside of their control. Additionally, we rely on sole suppliers for certain of our supplies. If these sole suppliers are unable to supply to us in the quantities we require, or at all, or otherwise default on their supply obligations to us, we may not be able to obtain alternative supplies from other suppliers on acceptable terms, in a timely manner, or at all.

There are, in general, relatively few alternative sources of supply for these components and red blood cells. These suppliers may be unable or unwilling to meet our future demands for our clinical trials or commercial sale. Establishing additional or replacement suppliers for these components and red blood cells could take a substantial amount of time and it may be difficult to establish replacement suppliers who meet regulatory requirements. Any disruption in supply from a supplier or manufacturing location could lead to supply delays or interruptions which would damage our business, financial condition, results of operations and prospects.

If we are able to find a replacement supplier, the replacement supplier would need to be qualified and may require additional regulatory authority approval, which could result in further delay. While we will seek to maintain adequate inventory of the red blood cells and other components and materials we will use to manufacture any future product candidates, any interruption or delay in the supply of red blood cells or other components or materials, or our inability to obtain red blood cells or other components or materials from alternate sources at acceptable prices in a timely manner, could impair our ability to meet future clinical and commercial demand.

In addition, as part of the FDA’s approval of any product candidates we may develop, we will also require FDA approval of the individual components of our process, which include the manufacturing processes and facilities of our suppliers.

Our reliance on these suppliers subjects us to a number of risks that could harm our business, and financial condition, including, among other things:

•material interruption of future product candidate or commercial supply resulting from modifications to or discontinuation of a supplier’s operations as a result of the ongoing COVID-19 pandemic;

•the continued manufacture and supply of raw materials and components for the Company’s preclinical and clinical development programs, which, in some cases, have been delayed or interrupted due to the ongoing COVID-19

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pandemic, and the availability of any of which could be significantly impaired in the future by the ongoing COVID-19 pandemic;

•delays in product shipments resulting from uncorrected defects, reliability issues, or a supplier’s variation in a component;

•a lack of long-term supply arrangements for key components with our suppliers;

•inability to obtain adequate supply in a timely manner, or to obtain adequate supply on commercially reasonable terms;

•difficulty and cost associated with locating and qualifying alternative suppliers for our red blood cells and other components and materials in a timely manner;

•production delays related to the evaluation and testing of products from alternative suppliers, and corresponding regulatory qualifications;

•continued delay in delivery due to our suppliers prioritizing other customer orders over ours, in particular to meet demand for vaccines, or other delays related to the ongoing COVID-19 pandemic;

•fluctuation in delivery by our suppliers due to changes in demand from us or their other customers; and

•economic weakness, including inflation, or political instability in particular foreign economies and markets.

If any of these risks materialize, our manufacturing costs could significantly increase and our ability to meet any future clinical and commercial demand for our products could be impacted.

Our future collaborations may be important to our business. If we are unable to maintain any of these collaborations, or if these collaborations are not successful, our business could be adversely affected.

We have limited capabilities for product development and do not yet have any capability for sales, marketing or distribution. Accordingly, we may enter into collaborations with other companies to provide us with important technologies and funding for our programs and technology, and we may receive additional technologies and funding under these and other collaborations in the future. Any future collaborations we enter into, may pose a number of risks, including the following:

•collaborators have significant discretion in determining the efforts and resources that they will apply;

•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 or license arrangements based on clinical trial results, changes in the collaborators’ strategic focus or available funding, or external factors, such as a strategic transaction that may 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 independently develop, or develop with third parties, products that compete directly or indirectly with our products and product candidates if the collaborators believe that the 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 our product candidates;

•collaborators may fail to comply with applicable regulatory requirements regarding the development, manufacture, distribution or marketing of a product candidate or product;

•collaborators with marketing and distribution rights to one or more of our product candidates that achieve regulatory approval may not commit sufficient resources to the marketing and distribution of such product or products;

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•disagreements with collaborators, including disagreements over proprietary rights, contract interpretation or the preferred course of development, might cause delays or terminations 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 that could jeopardize or invalidate our intellectual property or proprietary information or expose us to potential litigation;

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

•if a collaborator of ours is involved in a business combination, the collaborator might deemphasize or terminate the development or commercialization of any product candidate licensed to it by us; and

•collaborations may be terminated by the collaborator, and, if terminated, we could be required to raise additional capital to pursue further development or commercialization of the applicable product candidates.

If our potential future collaborations do not result in the successful discovery, development and commercialization of products or if one of our future collaborators terminates its agreement with us, we may not receive any future research funding or milestone or royalty payments under the collaboration. If we do not receive the funding we expect under these agreements, our development of our technology and product candidates could be delayed and we may need additional resources to develop product candidates and our technology. All of the risks relating to product development, regulatory approval and commercialization described in this Quarterly Report on Form 10-Q also apply to the activities of our future therapeutic collaborators.

Additionally, if one of our potential future collaborators terminates its agreement with us, we may find it more difficult to attract new collaborators and our perception in the business and financial communities could be adversely affected.

Collaborations are complex and time-consuming to negotiate and document. In addition, there have been a significant number of recent business combinations among large pharmaceutical companies that have resulted in a reduced number of potential future collaborators. We face significant competition in seeking appropriate collaborators. Our ability to reach a definitive agreement for a 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 increase our expenditures to fund 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 or do not have sufficient funds or expertise to undertake the necessary development and commercialization activities, we may not be able to further develop our product candidates, bring them to market and generate revenue from sales of drugs or continue to develop our technology, and our business may be materially and adversely affected.

Risks related to manufacturing and supply

The manufacturing process we have been developing is unique. If we or any third-party manufacturers that we may engage encounter difficulties in manufacturing our future product candidates or any of their components, our ability to provide supply of such product candidates for clinical trials or our products for patients, if approved, could be delayed or stopped, or we may be unable to maintain a commercially viable cost structure.

The manufacturing process we have been developing to produce our future product candidates is complex and novel and it has not previously been used to manufacture products for clinical testing or commercialization. As a result of these complexities, we expect that the cost to manufacture our future product candidates will be higher than traditional small molecule chemical compounds and monoclonal antibodies and that the manufacturing process will be less reliable and more difficult to reproduce. Furthermore, our manufacturing process development is at an early stage. The actual cost to manufacture and process any product candidates we may develop could be greater than we expect and could materially and adversely affect the commercial viability of such product candidates.

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Our manufacturing process may be susceptible to logistical issues associated with the collection of red blood cells from donors, procurement of proteins sourced from various suppliers and shipment to the product candidate manufacturing site, as well as shipment of the final product to clinical centers, manufacturing issues associated with interruptions in the manufacturing process, contamination, equipment or reagent failure, improper installation or operation of equipment, vendor or operator error, inconsistency in cell growth, and variability in product characteristics. Even minor deviations from normal manufacturing processes, or changes to these processes, could result in reduced production yields, lot failures, product defects, product recalls, product liability claims and other supply disruptions. If microbial, viral, or other contaminations are discovered in our product candidates or in our manufacturing facilities in which our product candidates are made, production at such manufacturing facilities may be interrupted for an extended period of time to investigate and remedy the contamination. Further, as product candidates are developed through preclinical to late-stage clinical trials toward approval and commercialization, it is common that various aspects of the development program, such as manufacturing methods, are altered along the way in an effort to optimize processes and results. Such changes can trigger regulatory review or delays and, regardless of regulatory feedback, will carry the risk that they will not achieve these intended objectives, and any of these changes could cause our product candidates to perform differently and affect the results of any future clinical trials we may conduct. Additionally, under the Reorganization Plan, we implemented certain cost reduction actions in September 2022, which are intended to focus our capital on advancing our next generation red blood cell technology platform. Because we are early in the development of our next generation red blood cell platform, and because of the complexity, novelty, and logistical challenges of the manufacturing process, we cannot assure you that our efforts to develop a manufacturing process for our next generation platform will be successful.

If we successfully develop our next generation manufacturing process, we likely will continue to optimize the process, and doing so is a difficult and uncertain task , and there are risks associated with scaling to the level required for clinical trials or commercialization, including, among others, cost overruns, potential problems with process scale-up, process reproducibility, stability issues, lot consistency, and timely availability of reagents and/or raw materials. Any contract manufacturer that we may engage with may not have the necessary capabilities to successfully implement our manufacturing process. If we are unable to adequately validate or scale-up the manufacturing process for our future product candidates as planned, we will need to transfer to an alternative contract manufacturer and complete the manufacturing validation process, which can be costly, lengthy and unpredictable. If we are able to adequately validate and scale-up the manufacturing process for our future product candidates with a contract manufacturer that we may engage, we may still need to negotiate with such contract manufacturer an agreement for commercial supply and it is not certain we will be able to come to agreement on terms acceptable to us. As a result, we may ultimately be unable to reduce the cost of goods for our future product candidates to levels that will allow for an attractive return on investment if and when those product candidates are commercialized.

The manufacturing process for any products that we may develop is subject to the FDA and foreign regulatory authority approval process, and we will need to contract with manufacturers who can meet all applicable FDA and foreign regulatory authority requirements on an ongoing basis. If we or our CMOs that we may engage are unable to reliably produce products to specifications acceptable to the FDA or other regulatory authorities, we may not obtain or maintain the approvals we need to commercialize such products. Even if we obtain regulatory approval for any of the product candidates we may develop, there is no assurance that either we or our CMOs that we may engage will be able to manufacture the approved product to specifications acceptable to the FDA or other regulatory authorities, to produce it in sufficient quantities to meet the requirements for the potential launch of the product, or to meet potential future demand. Any of these challenges could delay completion of clinical trials, require bridging clinical trials or the repetition of one or more clinical trials, increase clinical trial costs, delay approval of our product candidates, impair commercialization efforts, increase our cost of goods, and have an adverse effect on our business, financial condition, results of operations and growth prospects. We or CMOs we may engage may fail to manage the logistics of storing and shipping our raw materials and product candidates. Storage failures and shipment delays and problems caused by us, our vendors or other factors not in our control, such as weather, could result in the inability to manufacture product or the loss of usable product or could prevent or delay the delivery of product candidates to patients. Our future success depends on our ability to manufacture our products on a timely basis with acceptable manufacturing costs, while at the same time maintaining good quality control and complying with applicable regulatory requirements, and an inability to do so could have a material adverse effect on our business, financial condition, and results of operations. In addition, we could incur higher manufacturing costs if manufacturing processes or standards change, and we could need to replace, modify, design, or build and install equipment, all of which would require additional capital expenditures. Specifically, because our future product candidates may have a higher cost of goods than conventional therapies, the risk that coverage and reimbursement rates may be inadequate for us to achieve profitability may be greater.

Fluctuations in a CMO’s demand from other customers may affect their ability or willingness to deliver materials or products in a timely manner or may lead to long-term capacity constraints at the supplier. Additionally, a CMO may lose access to critical services or sustain damage to a facility, including losses due to man-made or natural disasters, geo-political events, or epidemics that may result in a sustained interruption in the manufacture and supply of our products. Our

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CMOs may also encounter financial or other hardships unrelated to our demand for materials, products and services, which could inhibit their ability to fulfill our orders and meet our requirements. If any CMO with whom we contract fails to perform its obligations, we may be forced to enter into an agreement with a different CMO, which we may not be able to do on reasonable terms, if at all. Our clinical trial supply for any clinical trials we may conduct in the future could be delayed significantly as a result. 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 candidates according to the specifications previously submitted to 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. In addition, 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.

Risks related to our common stock

The price of our stock has been and may continue to be volatile, and our stockholders could lose all or part of their investment.

The trading price of our common stock has been highly volatile and could continue to be subject to large fluctuations in response to the risk factors discussed in this section and elsewhere in this Quarterly Report on Form 10-Q, and other risk factors beyond our control, including:

•the commencement, enrollment or results of any future clinical trials we may conduct, or changes in the development status of our potential product candidates;

•any delay in our regulatory filings for any product candidates we may develop and any adverse development or perceived adverse development with respect to the applicable regulatory authority’s review of such filings;

•adverse or uninterpretable results from or delays in clinical trials of any product candidates we may develop, such as those we encountered with our Phase 1b clinical trial for RTX-134, which we have since discontinued;

•our decision to initiate a clinical trial, not to initiate a clinical trial or to terminate an existing clinical trial;

•adverse regulatory decisions, including failure to receive regulatory approval of any product candidates we may develop;

•changes in laws or regulations applicable to any product candidates we may develop, including but not limited to clinical trial requirements for approvals;

•adverse developments concerning the manufacture of any product candidates we may develop, such as the difficulties encountered by our former contract manufacturer for clinical supply of our discontinued Phase 1b clinical trial for RTX-134;

•our inability to obtain adequate product supply for any approved product or inability to do so at acceptable prices;

•our inability to establish collaborations, if needed;

•our failure to commercialize any product candidates we may develop;

•additions or departures of key scientific or management personnel;

•company-wide reductions in workforce;

•unanticipated serious safety concerns related to the use of any product candidates we may develop;

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•introduction of new products or services by our competitors;

•announcements of significant acquisitions, strategic partnerships, joint ventures or capital commitments by us or our competitors;

•our ability to effectively manage our growth;

•the size and growth of our initial target markets;

•actual or anticipated variations in quarterly operating results;

•our cash position;

•our failure to meet the estimates and projections of the investment community or that we may otherwise provide to the public;

•publication of research reports about us or our industry, or cellular therapies in particular, or positive or negative recommendations or withdrawal of research coverage by securities analysts;

•changes in the market valuations of similar companies;

•overall performance of the equity markets;

•sales of our common stock by us or our stockholders in the future;

•trading volume of our common stock;

•adoption of new accounting standards;

•ineffectiveness of our internal controls;

•disputes or other developments relating to proprietary rights, including patents, litigation matters and our ability to obtain patent protection for our technologies;

•significant lawsuits, including patent or stockholder litigation;

•general political and economic conditions; and

•other events or factors, many of which are beyond our control, including pandemics such as COVID-19.

In recent years, the stock market in general, and the market for biopharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors may negatively affect the market price of our common stock, regardless of our actual operating performance. Since our common stock began trading on The Nasdaq Global Select Market on July 18, 2018, our stock price has traded at prices as low as $0.32 per share and as high as $38.71 per share through October 31, 2022.

Additionally, technical factors in the public trading market for our stock may produce price movements that may or may not comport with macro, industry or company-specific fundamentals, including, without limitation, the sentiment of retail investors (including as may be expressed on financial trading and other social media sites), speculation in the press, in the investment community, or on the internet, including on online forums and social media, about us, our industry or our securities, the amount and status of short interest in our securities (including a “short squeeze”), access to margin debt, trading in options and other derivatives on our common stock and other technical trading factors. We may incur rapid and substantial decreases in our stock price in the foreseeable future that are unrelated to our operating performance or prospects. There can be no guarantee that our stock price will remain at current prices or that future sales of our common stock will not be at prices lower than the sales price in previous offerings. If the market price of our common stock does not exceed their purchase price, our stockholders may not realize any return on their investment in us and may lose some or all of their investment. In the past, securities class action litigation has often been instituted against companies following periods of volatility in the market price of a company’s securities. This type of litigation, if instituted, could result in

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substantial costs and a diversion of management’s attention and resources, which would harm our business, operating results or financial condition.

If we fail to maintain the listing of our common stock with a United States national securities exchange, the liquidity of our common stock could be adversely affected.

On July 27, 2022, we received a deficiency letter from the Listing Qualifications Department, or the Staff, of The Nasdaq Stock Market LLC, or Nasdaq, notifying us that, for the last 30 consecutive business days, the bid price for our common stock had closed below the $1.00 per share minimum bid price requirement for continued inclusion on the Nasdaq Global Select Market pursuant to Nasdaq Listing Rule 5450(a)(1) (which we refer to as the “Minimum Bid Price Requirement”). The Nasdaq deficiency letter has no immediate effect on the listing of our common stock, and our common stock will continue to trade on the Nasdaq Global Select Market under the symbol “RUBY” at this time.

In accordance with Nasdaq Listing Rule 5810(c)(3)(A), or the Compliance Period Rule, we have been provided a period of 180 calendar days, or until January 23, 2023 (which we refer to as the “Compliance Date”), to regain compliance with the Minimum Bid Price Requirement. If, at any time ending January 23, 2023, the bid price for our common stock closes at $1.00 or more for a minimum of ten consecutive business days, as required under the Compliance Period Rule, the Staff will provide written notification to us that we have regained compliance with the Minimum Bid Price Requirement and our common stock will continue to be eligible for listing on the Nasdaq Global Select Market, unless the Staff exercises its discretion to extend this ten-day period pursuant to Nasdaq Listing Rule 5810(c)(3)(H).

If we do not regain compliance with the Minimum Bid Price Requirement by the Compliance Date, we may be eligible for an additional 180 calendar day compliance period. To qualify, we would need to transfer the listing of our common stock to The Nasdaq Capital Market, provided that we meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, with the exception of the Minimum Bid Price Requirement, and would need to provide written notice to Nasdaq of our intention to cure the deficiency during the additional compliance period. To effect such a transfer, we would also need to pay an application fee to Nasdaq and provide written notice to the Staff of our intention to cure the deficiency during the second compliance period by effecting a reverse stock split if necessary. As part of its review process, the Staff will make a determination of whether it believes we will be able to cure the deficiency. Should the Staff conclude that we will not be able to cure the deficiency, the Staff will provide written notification to us that our common stock will be subject to delisting. At that time, we may appeal the Staff’s delisting determination to a Nasdaq Listing and Hearing Review Panel. However, there can be no assurance that, if we receive a delisting notice and appeal the delisting determination by the Staff to the panel, such appeal would be successful.

We intend to monitor the closing bid price of our common stock and may, if appropriate, consider available options to regain compliance with the Minimum Bid Price Requirement, which could include seeking to effect a reverse stock split. However, there can be no assurance that we will be able to regain compliance with the Minimum Bid Price Requirement, secure a second period of 180 days to regain compliance, or maintain compliance with any of the other Nasdaq continued listing requirements.

If our common stock is delisted by Nasdaq, our common stock may be eligible to trade on the OTC Bulletin Board or another over-the-counter market. Any such alternative would likely result in it being more difficult for us to raise additional capital through the public or private sale of equity securities and for investors to dispose of, or obtain accurate quotations as to the market value of, our common stock. In addition, there can be no assurance that our common stock would be eligible for trading on any such alternative exchange or markets.

We do not intend to pay dividends on our common stock so any returns will be limited to the value of our stock.

We currently anticipate that we will retain future earnings for the development, operation and expansion of our business and do not anticipate declaring or paying any cash dividends for the foreseeable future. In addition, under the Loan Agreement, we are restricted from paying any dividends or making any distributions on account of our capital stock. Any return to stockholders will therefore be limited in the foreseeable future to the appreciation of their stock.

Our principal stockholders and management own a significant percentage of our stock and will be able to exert significant control over matters subject to stockholder approval.

As of October 31, 2022, our executive officers, directors and their affiliates beneficially hold, in the aggregate, over 43% of our outstanding voting stock. These stockholders will have the ability to influence us through this ownership position. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders

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may be able to control elections of directors, amendments of our organizational documents, or approval of any merger, sale of assets, or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that our stockholders may feel are in their best interest as one of our stockholders.

We incur significant increased costs as a result of operating as a public company, and our management is required to devote substantial time to new compliance initiatives.

As a public company, we incur significant legal, accounting and other expenses. We are subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, 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 subsequently adopted by the SEC and The Nasdaq Stock Market 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.

As of December 31, 2021, we became a large accelerated filer and no longer qualify as an emerging growth company under the Jumpstart Our Business Startups Act, or the JOBS Act. Accordingly, we have ceased to be eligible for the emerging growth company provisions of the JOBS Act as of such date and are no longer able to avail ourselves of exemptions from various reporting requirements applicable to non-emerging growth companies. Such requirements include the requirement to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002, as amended, or the Sarbanes-Oxley Act, enhanced disclosure obligations regarding executive compensation in our periodic reports and proxy statements and the requirement to hold nonbinding advisory votes on executive compensation and stockholder approval of any golden parachute payments not previously approved. Additionally, we will no longer have the option to delay the adoption of new or revised accounting standards until such time as those standards apply to private companies. As a result, we may incur additional expenses or challenges relating to our transition to a large accelerated filer and/or our loss of emerging growth company status. Further, stockholder activism, the current political environment and the current high level 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 anticipate that as of December 31, 2022, we will be a non-accelerated filer and thus for the fiscal year ended December 31, 2023, we will not be required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002. In addition, as of June 30, 2022, we met the definition of a smaller reporting company and thus are able to take advantage of the scaled disclosure requirements for such companies, although we do not anticipate taking advantage of any of these scaled disclosure requirements until the beginning of the fiscal year ended December 31, 2023.

If securities or industry analysts do not publish research or publish inaccurate or unfavorable research about our business, our stock price and trading volume could decline.

The trading market for our common stock is influenced by research and reports that securities or industry analysts publish about us or our business. If one or more of the analysts who covers us downgrades our stock or publishes inaccurate or unfavorable research about our business, our stock price may decline. If one or more of these analysts ceases coverage of our company or fails to publish reports on us regularly, demand for our stock could decrease, which might cause our stock price and trading volume to decline.

We have broad discretion in the use of our existing cash, cash equivalents and investments and may not use them effectively.

Our management has broad discretion in the application of our cash, cash equivalents and investments. Because of the number and variability of factors that will determine our use of our cash, cash equivalents and investments, their ultimate use may vary substantially from their currently intended use. Our management might not apply our cash, cash equivalents and investments in ways that ultimately increase the value of our stockholders’ investment. The failure by our management to apply these funds effectively could harm our business. Pending their use, we may invest our cash in short-term, investment-grade, interest-bearing securities. These investments may not yield a favorable return to our stockholders. If we do not use our resources in ways that enhance stockholder value, we may fail to achieve expected financial results, which could cause our stock price to decline.

Risks related to corporate governance

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.

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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 chairman of the board of directors, the chief executive officer, or by a majority of the total number of authorized directors;

•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.

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 our stockholders to elect directors of their choosing or cause us to take other corporate actions they 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 specific courts as the exclusive forum for certain litigation that may be initiated by our stockholders, which could limit our stockholders’ ability to obtain a favorable judicial forum for disputes with us.

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 claim for (1) any derivative action or proceeding brought on our behalf; (2) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers, or other employees to us or our stockholders; (3) any action asserting a claim against us arising pursuant to any provision of the Delaware General Corporation Law or our certificate of incorporation or bylaws; (4) any action to interpret, apply, enforce or determine the validity of our certificate of incorporation or bylaws; or (5) any action asserting a claim against us governed by the internal affairs doctrine, or the Delaware Forum Provision. The Delaware Forum Provision will not apply to any causes of action arising under the Securities Act or the Exchange Act. Our amended and restated bylaws further provide that, unless we consent in writing to the selection of an alternative forum, the United States District Court for the District of Massachusetts is the sole and exclusive forum (1) for resolving any complaint asserting a cause of action arising under the Securities Act or the rules and regulations promulgated thereunder, and (2) of all suits in equity and actions at law brought to enforce any liability or duty created by the Securities Act or the rules and regulations thereunder, or the Federal Forum Provision, as our principal executive offices are located in Cambridge, Massachusetts. In addition, our amended and restated bylaws provide that any person or entity purchasing or otherwise acquiring any interest in shares of our common stock is deemed to have notice of and consented to the foregoing Delaware Forum Provision and Federal Forum Provision; provided, however, that stockholders cannot and will not be deemed to have waived our compliance with the U.S. federal securities laws and the rules and regulations thereunder.

We recognize that the Delaware Forum Provision and the Federal Forum Provision may impose additional litigation costs on stockholders in pursuing any such claims, particularly if the stockholders do not reside in or near the State of Delaware

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or the Commonwealth of Massachusetts. Additionally, the forum selection clauses in our amended and restated by-laws 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 the filing of lawsuits against us and our directors, officers and employees even though an action, if successful, might benefit our stockholders. 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 are “facially valid” under Delaware law, there is uncertainty as to whether other courts will enforce our Federal Forum Provision. The Federal Forum Provision may also impose additional litigation costs on us and/or our stockholders who assert that the provision is invalid or unenforceable, and if the Federal Forum Provision is found to be unenforceable, we may incur additional costs with resolving such matters. The Court of Chancery of the State of Delaware or the United States District Court for the District of Massachusetts 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.

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Item 2. Unregistered Sales of Equity Securities and Use of Proceeds

None.

Item 3. Defaults Upon Senior Securities

Not applicable.

Item 4. Mine Safety Disclosures

Not applicable.

Item 5. Other Information

None.

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The exhibits filed as part of this Quarterly Report on Form 10-Q are set forth on the Exhibit Index, which Exhibit Index is incorporated herein by reference.

Item 6. Exhibits

3.1	Amended and Restated Certificate of Incorporation of Rubius Therapeutics, Inc. (Incorporated by reference to Exhibit 3.1 to the Registrant’s Form 8- K (File No. 001-38586) filed on July 23, 2018).
3.2	Certificate of Amendment of Amended and Restated Certificate of Incorporation of Rubius Therapeutics, Inc. (Incorporated by reference to Exhibit 3.1 to the Registrant’s Form 8-K (File No. 001-38586) filed on July 7, 2022).
3.3	Amended and Restated Bylaws of Rubius Therapeutics, Inc. (Incorporated by reference to Exhibit 3.2 to the Registrant’s Form 8- K (File No. 001- 38586) filed on July 23, 2018).
4.1	Specimen Common Stock Certificate (Incorporated by reference to Exhibit 4.1 to the Registrant’s Registration Statement on Form S-1, as amended (File No. 333-225840) filed on July 2, 2018)
4.2	Form of Senior Indenture between the Registrant and one or more trustees to be named (Incorporated by reference to Exhibit 4.3 to the Registrant’s Registration Statement on Form S-3 (File No. 333-265482) filed on June 8, 2022)
4.3	Form of Subordinated Indenture between the Registrant and one or more trustees to be named (Incorporated by reference to Exhibit 4.4 to the Registrant’s Registration Statement on Form S-3 (File No. 333-265482) filed on June 8, 2022)
31.1*	Certification of Principal Executive Officer pursuant to Rule 13a- 14(a) or Rule 15d- 14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2*	Certification of Principal Financial Officer pursuant to Rule 13a- 14(a) or Rule 15d- 14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
32.1†	Certification of Principal Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
32.2†	Certification of 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 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 Calculation Linkbase Document.
101.DEF*	Inline XBRL Taxonomy Extension Definition Linkbase Document.
101.LAB*	Inline XBRL Taxonomy Extension Label Linkbase Document.

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101.PRE*	Inline XBRL Taxonomy Extension Presentation Linkbase Document.
104*	Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

* Filed herewith.

† This certification will not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section. Such certification will not be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, except to the extent specifically incorporated by reference into such filing.

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SIGNATURES

Pursuant to the requirements 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.

	RUBIUS THERAPEUTICS, INC.
Date: November 9, 2022	By:	/s/ Pablo J. Cagnoni
		Pablo J. Cagnoni, M.D.
		Chief Executive Officer
		(Principal Executive Officer)
Date: November 9, 2022	By:	/s/ Jose Carmona
		Jose Carmona
		Chief Financial Officer
		(Principal Financial Officer)

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EX-31.1

EXHIBIT 31.1

CERTIFICATION PURSUANT TO SECURITIES AND EXCHANGE ACT OF 1934

RULE 13A-14 AS ADOPTED PURSUANT TO SECTION 302 OF SARBANES-OXLEY ACT OF 2002

CERTIFICATION

I, Pablo J. Cagnoni, M.D., certify that:

1.	I have reviewed this Quarterly Report on Form 10-Q of Rubius Therapeutics, 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: November 9, 2022	By:	/s/ Pablo J. Cagnoni
		Pablo J. Cagnoni, M.D.
		Chief Executive Officer and President (Principal Executive Officer)

EX-31.2

EXHIBIT 31.2

CERTIFICATION PURSUANT TO SECURITIES AND EXCHANGE ACT OF 1934

RULE 13A-14 AS ADOPTED PURSUANT TO SECTION 302 OF SARBANES-OXLEY ACT OF 2002

CERTIFICATION

I, Jose Carmona, certify that:

1.	I have reviewed this Quarterly Report on Form 10-Q of Rubius Therapeutics, 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: November 9, 2022	By:	/s/ Jose Carmona
		Jose Carmona
		Chief Financial Officer (Principal Financial Officer)

EX-32.1

Exhibit 32.1

CERTIFICATION 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 Quarterly Report on Form 10-Q of Rubius Therapeutics, Inc. (the “Company”) for the period ended September 30, 2022, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, Pablo J. Cagnoni, M.D., Chief Executive Officer of the Company, hereby certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to his knowledge:

(1) the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: November 9, 2022	By:	/s/ Pablo J. Cagnoni
		Pablo J. Cagnoni, M.D.
		Chief Executive Officer and President
		(Principal Executive Officer)

EX-32.2

Exhibit 32.2

CERTIFICATION 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 Quarterly Report on Form 10-Q of Rubius Therapeutics, Inc. (the “Company”) for the period ended September 30, 2022, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, Jose Carmona, Chief Financial Officer of the Company, hereby certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to his knowledge:

(1) the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: November 9, 2022	By:	/s/ Jose Carmona
		Jose Carmona
		Chief Financial Officer
		(Principal Financial Officer)

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Cover Page - shares	9 Months Ended
	Sep. 30, 2022	Oct. 31, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	001-38586
Entity Registrant Name	RUBIUS THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-2688109
Entity Address, Address Line One	399 Binney Street
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02139
City Area Code	617
Local Phone Number	679-9600
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	RUBY
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		90,371,532
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001709401
Amendment Flag	false

XML

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 103,884,000	$ 225,848,000
Assets held-for-sale, not part of disposal group	4,257,000	0
Prepaid expenses and other current assets	2,682,000	3,975,000
Total current assets	110,823,000	229,823,000
Operating lease, right-of-use asset	31,207,000	35,095,000
Property, plant and equipment, net	27,094,000	51,530,000
Restricted cash	1,573,000	1,573,000
Total assets	170,697,000	318,021,000
Current liabilities:
Accounts payable	8,717,000	11,572,000
Accrued expenses and other current liabilities	14,695,000	14,072,000
Operating lease liabilities	9,212,000	9,015,000
Total current liabilities	32,624,000	34,659,000
Long-term debt, net of discount	76,829,000	76,154,000
Other long-term liabilities	0	135,000
Operating lease liabilities, net of current portion	24,657,000	28,291,000
Total liabilities	134,110,000	139,239,000
Commitments and contingencies (see Note 9)
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized at September 30, 2022 and December 31, 2021; no shares issued or outstanding at September 30, 2022 and December 31, 2021	0	0
Common stock, $0.001 par value; 300,000,000 and 150,000,000 shares authorized at September 30, 2022 and December 31, 2021, respectively; 90,370,532 and 90,063,770 shares issued and outstanding at September 30, 2022 and December 31, 2021, respectively	90,000	90,000
Additional paid-in capital	873,041,000	855,710,000
Accumulated deficit	(836,544,000)	(677,018,000)
Total stockholders' equity	36,587,000	178,782,000
Total liabilities and stockholders' equity	$ 170,697,000	$ 318,021,000
Common stock, share authorized (in shares)	300,000,000	150,000,000

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CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, share authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, share authorized (in shares)	300,000,000	150,000,000
Common stock, shares issued (in shares)	90,370,532	90,063,770
Common stock, shares outstanding (in shares)	90,370,532	90,063,770

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CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Revenue	$ 0	$ 0	$ 0	$ 0
Operating expenses:
Research and development	24,229	38,014	95,526	101,763
General and administrative	7,301	12,035	29,772	39,126
Restructuring and impairment charges	30,052	0	30,052	0
Total operating expenses	61,582	50,049	155,350	140,889
Loss from operations	(61,582)	(50,049)	(155,350)	(140,889)
Other income (expense):
Interest income	392	23	695	75
Interest expense	(1,736)	(1,711)	(4,995)	(4,771)
Other income, net	53	2,721	124	4,059
Total other income (expense), net	(1,291)	1,033	(4,176)	(637)
Net loss	$ (62,873)	$ (49,016)	$ (159,526)	$ (141,526)
Net loss per share, basic (in dollars per share)	$ (0.70)	$ (0.55)	$ (1.77)	$ (1.62)
Net loss per share, diluted (in dollars per share)	$ (0.70)	$ (0.55)	$ (1.77)	$ (1.62)
Weighted-average common shares outstanding, basic (in shares)	90,364,222	89,807,383	90,262,487	87,240,694
Weighted-average common shares outstanding, diluted (in shares)	90,364,222	89,807,383	90,262,487	87,240,694
Comprehensive loss:
Net loss	$ (62,873)	$ (49,016)	$ (159,526)	$ (141,526)
Other comprehensive income (loss):
Unrealized gains (losses) on investments, net of tax of $0	122	(1)	0	(4)
Comprehensive loss	$ (62,751)	$ (49,017)	$ (159,526)	$ (141,530)

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CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Unrealized gains (losses) on investments, tax	$ 0	$ 0	$ 0	$ 0

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CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities:
Net loss	$ (159,526)	$ (141,526)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	17,099	26,428
Depreciation and amortization expense	5,827	4,331
Amortization (accretion) of premium (discount) on investments	(305)	118
Non-cash interest expense	621	1,036
Impairment charges	17,787	0
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	1,131	(1,226)
Operating lease, right-of-use-asset	3,888	4,156
Accounts payable	(2,551)	2,773
Accrued expenses and other current liabilities	1,976	(416)
Other long-term liabilities	(135)	(102)
Operating lease liabilities	(3,437)	(3,477)
Net cash used in operating activities	(117,625)	(107,905)
Cash flows from investing activities:
Purchases of property, plant and equipment	(5,038)	(2,280)
Purchases of investments	(78,445)	0
Sales and maturities of investments	78,750	85,000
Net cash provided by (used in) investing activities	(4,733)	82,720
Cash flows from financing activities:
Proceeds from underwritten public offering of common stock, net of commissions and underwriting discounts	0	188,000
Payments of offering costs	0	(360)
Payments of debt issuance costs	0	(150)
Proceeds from issuance of common stock upon exercise of stock options and under employee stock purchase plan	232	10,547
Net cash provided by financing activities	232	198,037
Net increase (decrease) in cash, cash equivalents and restricted cash	(122,126)	172,852
Cash, cash equivalents and restricted cash at beginning of period	227,583	92,901
Cash, cash equivalents and restricted cash at end of period	105,457	265,753
Supplemental cash flow information:
Cash paid for interest	4,374	3,635
Cash paid for leases	5,386	5,675
Supplemental disclosure of non-cash investing and financing information:
Purchases of property, plant and equipment included in accounts payable or accrued expenses	333	1,145
Offering costs included in accounts payable and accrued expenses	$ 0	$ 35

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CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Accumulated other comprehensive income (loss)	Accumulated deficit
Balances at beginning of period (in shares) at Dec. 31, 2020		81,053,651
Balances at beginning of period at Dec. 31, 2020	$ 141,560	$ 81	$ 621,946	$ 4	$ (480,471)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from public offering, net of commissions, underwriting discounts and offering costs (in shares)		6,896,552
Issuance of common stock from public offering, net of commissions, underwriting discounts and offering costs of $800	187,200	$ 7	187,193
Issuance of common stock upon exercise of stock options (in shares)		1,237,324
Issuance of common stock upon exercise of stock options	5,908	$ 1	5,907
Stock-based compensation expense	8,642		8,642
Unrealized gain (loss) on investments	3			3
Net loss	(42,330)				(42,330)
Balances at end of period (in shares) at Mar. 31, 2021		89,187,527
Balances at end of period at Mar. 31, 2021	300,983	$ 89	823,688	7	(522,801)
Balances at beginning of period (in shares) at Dec. 31, 2020		81,053,651
Balances at beginning of period at Dec. 31, 2020	141,560	$ 81	621,946	4	(480,471)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(141,526)
Balances at end of period (in shares) at Sep. 30, 2021		89,862,482
Balances at end of period at Sep. 30, 2021	224,205	$ 90	846,112	0	(621,997)
Balances at beginning of period (in shares) at Mar. 31, 2021		89,187,527
Balances at beginning of period at Mar. 31, 2021	300,983	$ 89	823,688	7	(522,801)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		532,400
Issuance of common stock upon exercise of stock options	3,720	$ 1	3,719
Stock-based compensation expense	9,597		9,597
Unrealized gain (loss) on investments	(6)			(6)
Net loss	(50,180)				(50,180)
Balances at end of period (in shares) at Jun. 30, 2021		89,719,927
Balances at end of period at Jun. 30, 2021	264,114	$ 90	837,004	1	(572,981)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		142,555
Issuance of common stock upon exercise of stock options	919		919
Stock-based compensation expense	8,189		8,189
Unrealized gain (loss) on investments	(1)			(1)
Net loss	(49,016)				(49,016)
Balances at end of period (in shares) at Sep. 30, 2021		89,862,482
Balances at end of period at Sep. 30, 2021	224,205	$ 90	846,112	0	(621,997)
Balances at beginning of period (in shares) at Dec. 31, 2021		90,063,770
Balances at beginning of period at Dec. 31, 2021	178,782	$ 90	855,710	0	(677,018)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		18,228
Issuance of common stock upon exercise of stock options	76		76
Vesting of restricted stock units (in shares)		104,628
Vesting of restricted stock units	0
Stock-based compensation expense	8,260		8,260
Unrealized gain (loss) on investments	(57)			(57)
Net loss	(52,412)				(52,412)
Balances at end of period (in shares) at Mar. 31, 2022		90,186,626
Balances at end of period at Mar. 31, 2022	134,649	$ 90	864,046	(57)	(729,430)
Balances at beginning of period (in shares) at Dec. 31, 2021		90,063,770
Balances at beginning of period at Dec. 31, 2021	178,782	$ 90	855,710	0	(677,018)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(159,526)
Balances at end of period (in shares) at Sep. 30, 2022		90,370,532
Balances at end of period at Sep. 30, 2022	36,587	$ 90	873,041	0	(836,544)
Balances at beginning of period (in shares) at Mar. 31, 2022		90,186,626
Balances at beginning of period at Mar. 31, 2022	134,649	$ 90	864,046	(57)	(729,430)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		24,000
Issuance of common stock upon exercise of stock options	22		22
Vesting of restricted stock units (in shares)		2,500
Vesting of restricted stock units	0
Stock issued during period, shares, employee stock purchase plans (in shares)		143,906
Issuance of common stock under employee stock purchase plan	134		134
Stock-based compensation expense	5,041		5,041
Unrealized gain (loss) on investments	(65)			(65)
Net loss	(44,241)				(44,241)
Balances at end of period (in shares) at Jun. 30, 2022		90,357,032
Balances at end of period at Jun. 30, 2022	95,540	$ 90	869,243	(122)	(773,671)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Vesting of restricted stock units (in shares)		13,500
Vesting of restricted stock units	0
Stock-based compensation expense	3,798		3,798
Unrealized gain (loss) on investments	122			122
Net loss	(62,873)				(62,873)
Balances at end of period (in shares) at Sep. 30, 2022		90,370,532
Balances at end of period at Sep. 30, 2022	$ 36,587	$ 90	$ 873,041	$ 0	$ (836,544)

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CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Statement of Stockholders' Equity [Abstract]
Stock issuance costs						$ 800
Issuance of common stock upon exercise of stock options		$ 22	$ 76	$ 919	$ 3,720	5,908
Stock-based compensation expense	$ 3,798	5,041	8,260	8,189	9,597	8,642
Unrealized gain (loss) on investments	122	(65)	(57)	(1)	(6)	3
Net loss	(62,873)	(44,241)	(52,412)	(49,016)	(50,180)	(42,330)	$ (159,526)	$ (141,526)
Stockholders' Equity Attributable to Parent	$ 36,587	$ 95,540	$ 134,649	$ 224,205	$ 264,114	$ 300,983	$ 36,587	$ 224,205	$ 178,782	$ 141,560

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Nature of the Business and Basis of Presentation

9 Months Ended

Sep. 30, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of the Business and Basis of Presentation

Nature of the Business and Basis of Presentation

Rubius Therapeutics, Inc. (“Rubius” or the “Company”) is a biopharmaceutical company that is using chemical conjugation to turn red blood cells into medicines, called Red Cell Therapeutics, for the treatment of cancer and autoimmune diseases. Rubius was incorporated in April 2013 as VL26, Inc. under the laws of the State of Delaware. In January 2015, the Company changed its name to Rubius Therapeutics, Inc.

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations, the ability to establish clinical- and commercial-scale manufacturing processes and the ability to secure additional capital to fund operations. In addition, the Company is subject to uncertainty regarding the performance and safety of its product candidates in humans. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s drug development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

The Company is monitoring the potential impact of the novel coronavirus (“COVID-19”), if any, on the carrying value of certain assets. To date, the Company has not experienced material business disruption, nor has it incurred impairment of any assets as a result of COVID-19. The extent to which these events may impact the Company’s business will depend on future developments, which are highly uncertain and cannot be predicted at this time. The duration and intensity of these impacts and resulting disruption to the Company’s operations is uncertain and the Company will continue to assess the financial impact.

On July 20, 2018, the Company completed its initial public offering (“IPO”), pursuant to which it issued and sold 12,055,450 shares of common stock, inclusive of 1,572,450 shares sold by the Company pursuant to the full exercise of the underwriters’ option to purchase additional shares. The aggregate net proceeds received by the Company from the IPO were $254.3 million, after deducting underwriting discounts and commissions and other offering costs. Upon the closing of the IPO, all of the shares of the Company’s outstanding convertible preferred stock then outstanding automatically converted into 51,845,438 shares of common stock.

On March 18, 2021, the Company completed an underwritten public offering (the “March 2021 Offering”), pursuant to which it issued and sold 6,896,552 shares of common stock. The aggregate net proceeds received by the Company from the March 2021 Offering were $187.2 million, after deducting underwriting discounts and commissions and other offering costs.

In September 2022, the Company's Board of Directors approved certain operational and organizational steps that the Company will undertake in connection with a new strategic reorganization plan and related cost-saving measures (collectively, the “Reorganization Plan”). The Company discontinued its ongoing Phase 1 clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors and restructured the organization to support advancing drug candidates based on its next generation platform. Under the Reorganization Plan, the Company also reduced its overall workforce by approximately 75%, primarily consisting of employees who were focused on clinical development of RTX-240 and RTX-224, with the remainder coming from its manufacturing and general and administrative functions. Additionally, the Company is exploring the sale of its manufacturing facility in Smithfield, Rhode Island.

The Company’s cash and cash equivalents as of September 30, 2022 is $103.9 million. In October 2022, the Company used $75.7 million of its cash and cash equivalents to extinguish its long-term debt and satisfy its obligations under the loan and security agreement with SLR Investment Corp (Note 6).

On November 2, 2022, the Company announced that, in light of the Company’s financial condition, including the repayment and termination of its $75.0 million credit facility with SLR Investment Corp., and the early stage of its programs, its Board of Directors approved a plan to review strategic alternatives, including a sale or merger of the Company or one or more sales of its assets, and to significantly and immediately reduce its operations (the “Strategic Plan”). In connection with the Strategic Plan, the Company has terminated 42 of its employees (representing 82% of its current employee base), leaving a core team of individuals to lead the strategic review process.

As a result of the Strategic Plan, the Company’s current financial resources and currently forecasted operating plan would allow the Company to operate into the first quarter of 2023. The Company expects its Strategic Plan will reduce its operating expenses with the goal of allowing the Company to pursue any viable strategic alternatives. There is no guarantee that this plan will be successful. The Company may not be able to successfully pursue any strategic alternatives and, even if certain strategic alternatives may be available, the Company cannot provide any assurance that the strategic alternatives review process will result in any particular alternative, transaction or value.

Under Accounting Standards Update (“ASU”) 2014-15, Presentation of Financial Statements—Going Concern (Subtopic 205-40) (“ASC 205-40”), the Company has the responsibility to evaluate whether conditions and/or events raise substantial doubt about its ability to meet its future financial obligations as they become due within one year after the date that the financial statements are issued.

As of September 30, 2022, the Company had an accumulated deficit of $836.5 million, and cash and cash equivalents of $103.9 million. For the nine months ended September 30, 2022, the Company incurred a loss of $159.5 million and used $117.6 million of cash in operations. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future. Management has assessed the Company’s ability to continue as a going concern in accordance with the requirements of ASC 205-40 and based on its recurring losses from operations incurred since inception, expectation of continuing operating losses for the foreseeable future, and the need to raise additional capital to finance its future operations, as of November 9, 2022, the issuance date of the interim condensed consolidated financial statements for the three and nine month periods ended September 30, 2022, the Company has concluded that there is substantial doubt about its ability to continue as a going concern for a period of one year from the date that these interim condensed consolidated financial statements are issued. The accompanying condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Accordingly, the condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

The Company’s condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”).

The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation.

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Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

Unaudited Interim Financial Information

The condensed consolidated balance sheet at December 31, 2021 was derived from audited financial statements but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of September 30, 2022 and for the three and nine months ended September 30, 2022 and 2021 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K for the year-ended December 31, 2021, on file with the SEC. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position as of September 30, 2022 and condensed consolidated results of operations for the three and nine months ended September 30, 2022 and 2021 and the condensed consolidated cash flows for the nine months ended September 30, 2022 and 2021 have been made. The Company’s condensed consolidated results of operations for the three and nine months ended September 30, 2022 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2022.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the accrual of research and development expenses, the valuation of stock-based awards and the valuation of long-lived assets. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that

it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts and experience. Actual results may differ from those estimates or assumptions.

The full extent to which the ongoing COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, including clinical trials, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19. As of the date of issuance of these unaudited condensed consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update estimates, judgments or revise the carrying value of any assets or liabilities. Actual results may differ from those estimates or assumptions.

Concentrations of Credit Risk and of Significant Suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company’s cash and cash equivalents, as of September 30, 2022, consisted of cash and money market accounts. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and raw materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services or the availability of raw materials.

Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents.

Restricted Cash

As of September 30, 2022 and December 31, 2021, the Company maintained letters of credit for the benefit of the landlords of its leased properties totaling $1.6 million and $1.7 million, respectively. The Company was required to maintain separate cash balances of these amounts to secure the letters of credit. Related to these separate cash balances, the Company included $1.6 million in restricted cash (non-current) in its condensed consolidated balance sheet as of September 30, 2022. As of December 31, 2021, the Company included $0.1 million in prepaid expenses and other current assets and $1.6 million in restricted cash (non-current) in its condensed consolidated balance sheet.

Cash, cash equivalents and restricted cash presented in the accompanying condensed consolidated statement of cash flows was $105.5 million and $265.8 million for the nine months ended September 30, 2022 and 2021, respectively, of which $1.6 million and $1.7 million was restricted cash, respectively.

Fair Value Measurements

Certain assets and liabilities are carried at fair value under 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 and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. The carrying value of the Company’s long-term debt approximates its fair value due to its variable interest rate, which approximates a market interest rate.

Investments

The Company’s investments are classified as available-for-sale and are carried at fair value. Realized gains and losses and declines in value are based on the specific identification method and are included as a component of other income (expense), net in the condensed consolidated statements of operations and comprehensive loss. The Company classifies its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such investments are available for current operations.

The Company evaluates its investments with unrealized losses for impairment. When assessing investments for unrealized declines in value, the Company considers whether the decline in value is related to a credit loss or non-credit loss. For credit losses, the Company reduces the investment to fair value through an allowance for credit losses recorded to the balance sheet and corresponding charge to the statement of operations. The allowance for credit losses and corresponding impairment charge is adjusted each period for changes in fair value. For non-credit losses, the Company reduces the investment to fair value through a charge to the statement of comprehensive loss, reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. No such credit losses were recorded during the periods presented.

Assets Held for Sale

The Company classifies its long-lived assets to be sold as held for sale in the period (i) the Company has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures a long-lived asset that is classified as held for sale at the lower of its carrying value or fair value, less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a long-lived asset until the date of sale. Upon designation as an asset held for sale, the Company stops recording depreciation and amortization expense on long-lived assets. The Company assesses the fair value of a long-lived asset, less any costs to sell, at each reporting period and until the asset is no longer classified as held for sale.

Leases

At the inception of an arrangement as lessee or lessor, the Company determines whether the arrangement is or contains a lease. Operating lease cost is recognized over the lease term on a straight-line basis. Variable lease cost and short-term leases (lease terms less than 12 months) are recognized as incurred. For both lessee and lessor arrangements, variable lease payments are the amounts owed by the Company to a lessor that are not fixed, such as reimbursement for common area maintenance and utilities costs, and are expensed when incurred. When determining the lease term, the Company includes options to extend or terminate the lease when it is reasonably certain that it will exercise that option.

For lessee arrangements, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes its incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. Operating leases are recognized on the balance sheet as right-of-use assets, operating lease liabilities current and operating lease liabilities non-current.

The Company has elected the following lease policies at the inception of a lease: (1) for lessee and lessor arrangements within all asset classes, combine lease and non-lease components as a single component, with the lease expense recognized over the expected term on a straight-line basis and (2) for lessee arrangements, apply short-term lease exemption for all leases that qualify, where a right-of-use asset or lease liability will not be recognized for leases with terms of one year or less.

Impairment of Long-Lived Assets Long-lived assets consist of property, plant and equipment and operating lease, right-of-use asset. 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 underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of 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 and eventual disposition 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.

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Investments and Fair Value of Financial Assets and Liabilities

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

Investments and Fair Value of Financial Assets and Liabilities

Investments and Fair Value of Financial Assets and Liabilities

The Company had no investments as of September 30, 2022 or December 31, 2021.

The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):

	September 30, 2022
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. government money market funds	$	96,729	$	—	$	—	$	96,729
	$	96,729	$	—	$	—	$	96,729

	December 31, 2021
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S government money market funds	$	217,009	$	—	$	—	$	217,009
	$	217,009	$	—	$	—	$	217,009

U.S. government money market funds were valued by the Company based on quoted market prices, which represent a Level 1 measurement within the fair value hierarchy. There were no changes to the valuation methods used during the nine months ended September 30, 2022. The Company evaluates transfers between levels at the end of each reporting period. There were no transfers between Level 1, Level 2 or Level 3 during the nine months ended September 30, 2022.

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Property, Plant and Equipment, Net and Assets Held for Sale

9 Months Ended

Sep. 30, 2022

Property, Plant and Equipment, Net [Abstract]

Property, Plant and Equipment, Net and Assets Held for Sale

Property, Plant and Equipment, Net and Assets Held for SaleProperty, plant and equipment, net and assets held for sale consisted of the following, after the effects of impairment charges and held-for-sale reclassifications (in thousands):

	September 30, 2022		December 31, 2021
Land	$	1,300	$	1,300
Manufacturing facility	25,469		33,203
Manufacturing equipment	7,329		8,831
Laboratory equipment	1,333		17,501
Computer equipment	2,160		2,645
Furniture and fixtures	17		1,281
Leasehold improvements	570		444
Construction-in-progress	—		4,181
	38,178		69,386
Less: Accumulated depreciation and amortization	(11,084)		(17,856)
	$	27,094	$	51,530
Assets held for sale	$	4,257	$	—

During the three and nine months ended September 30, 2022, the Company recorded impairment charges of $17.8 million due to its Reorganization Plan (Note 11).

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Accrued Expenses and Other Current Liabilities	9 Months Ended
	Sep. 30, 2022
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current LiabilitiesAccrued expenses and other current liabilities consisted of the following (in thousands):

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Debt

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Debt

Debt

On December 21, 2018 (the “Closing Date”), the Company entered into a loan and security agreement (the "Original Loan Agreement," and, as amended, the “Loan Agreement”) with Solar Capital Ltd., now SLR Investment Corp. ("SLR"), as collateral agent for the lenders party thereto for an aggregate principal amount of $75.0 million. The aggregate principal amount was funded in three tranches of term loans of $25.0 million each. On the Closing Date, the Company made an initial borrowing of $25.0 million. In June 2019, the Company made a second borrowing of $25.0 million and in June 2020, the Company made a third and final borrowing of $25.0 million.

On June 22, 2021 (the “Amendment Closing Date”), the Company entered into an amendment (the “Amendment”) to the Original Loan Agreement. Pursuant to the Amendment, the Company and its lenders agreed to extend the interest-only period applicable to borrowings under the Loan Agreement from December 21, 2021 until July 1, 2024 and the final maturity date from December 21, 2023 until June 1, 2026. An additional tranche in the amount of $35.0 million is available at the request of the Company prior to the final maturity date, to be provided at the sole discretion of the lenders. The Amendment increases the LIBOR interest rate floor from 0.00% to 2.10%. Interest on the outstanding loan balance will accrue at a rate of 5.50%, plus the greater of 2.10% or the one-month U.S. LIBOR rate. Certain back-end fees are due to the lender at the time of final repayment based on the total funded term loans. The Company accrues the back-end fees that will be due at final repayment to outstanding debt by charges to interest expense over the term of the loans using the effective interest method. The term loans are subject to a prepayment fee of 1.00% if prepayment occurs within the first year subsequent to the Amendment Closing Date, 0.50% in the second year and 0.25% in the third year through final maturity date.

As the terms of the Amendment were not substantially different than the terms of the Original Loan Agreement, the Amendment was accounted for as a debt modification. In conjunction with the Amendment, the Company incurred issuance costs of $0.2 million payable to the lenders, which were recorded as an additional debt discount and will be amortized to interest expense over the remaining term, together with unamortized original issuance costs as of the Amendment Closing Date, using the effective interest method.

The Loan Agreement contains financial covenants that require the Company to maintain either a minimum cash balance of $10.0 million plus accounts payable that are aged longer than ninety days or a minimum market capitalization threshold. The Company was in compliance with all such financial covenants as of September 30, 2022. The Loan Agreement contains customary representations, warranties and covenants and also includes customary events of default, including payment defaults, breaches of covenants, change of control and a material adverse change default. Upon the occurrence of an event of default, a default interest rate of an additional 4.00% per annum may be applied to the outstanding loan balances, and the lenders may declare all outstanding obligations immediately due and payable. Borrowings under the Loan Agreement are collateralized by substantially all of the Company’s assets, other than its intellectual property.

As of September 30, 2022, the estimated future principal payments due under the Loan Agreement were as follows (in thousands):

Year ending December 31,
2022 (three months ending December 31)	$	—
2023	—
2024	18,750
2025	37,500
2026 and thereafter	18,750
	$	75,000

On October 13, 2022, the Company entered into a payoff letter with SLR, under which the Company voluntarily prepaid SLR approximately $75.7 million, in full satisfaction of all obligations, including all outstanding principal, accrued interest, fees, costs, expenses and other amounts chargeable, under the Loan Agreement. The payoff letter also provided for the termination of all commitments and obligations under the Loan Agreement and release of all liens held by SLR on the Company’s assets.

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Equity

9 Months Ended

Sep. 30, 2022

Stockholders' Equity Note [Abstract]

Equity

Equity

Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are not entitled to receive dividends, unless declared by the board of directors.

On July 20, 2018, the Company filed a restated certificate of incorporation in the State of Delaware, which, among other things, restated the number of shares of all classes of stock that the Company has authority to issue to 160,000,000 shares, consisting of (i) 150,000,000 shares of common stock, $0.001 par value per share, and (ii) 10,000,000 shares of preferred stock, $0.001 par value per share. The preferred stock will have such rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences, as shall be determined by the Company’s board of directors upon issuance. The shares of preferred stock are currently undesignated.

On August 1, 2019, the Company entered into a Distribution Agreement (the “Distribution Agreement”) with J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC (the “Sales Agents”), pursuant to which the Company was able to issue and sell, from time to time, shares of its common stock having an aggregate offering price of up to $100.0 million through the Sales Agents. As of September 30, 2022, no shares of common stock were issued and sold pursuant to the Distribution Agreement, which expired in accordance with its terms on August 21, 2022, and the applicable registration statement is no longer effective.

On March 18, 2021, the Company completed the March 2021 Offering, pursuant to which it issued and sold 6,896,552 shares of common stock. The aggregate net proceeds received by the Company from the March 2021 Offering were $187.2 million, after deducting underwriting discounts and commissions and other offering costs.

On July 7, 2022, the Company filed an amendment to its Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware which increased the number of shares of common stock that the Company has

authority to issue from 150,000,000 to 300,000,000 shares. The number of shares of preferred stock authorized for issuance was not impacted by this amendment.

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Stock-Based Compensation

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

Stock-Based Compensation

Service-Based Stock Options

During the nine months ended September 30, 2022, the Company granted options with service-based vesting conditions for the purchase of 4,104,403 shares of common stock with a weighted average exercise price of $4.37 per share and a weighted average grant-date fair value of $2.98 per share.

Stock-Based Compensation

The Company recorded stock-based compensation expense in the following expense categories of its condensed consolidated statements of operations and comprehensive loss (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development expenses	$	2,266	$	3,408	$	7,958	$	8,995
General and administrative expenses	1,532		4,781		9,141		17,433
	$	3,798	$	8,189	$	17,099	$	26,428

As of September 30, 2022, total unrecognized compensation cost related to the unvested stock-based awards was $36.2 million, which is expected to be recognized over a weighted average period of 2.3 years.

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Commitments and Contingencies

9 Months Ended

Sep. 30, 2022

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Commitments and Contingencies

License Agreement with the Whitehead Institute for Biomedical Research

The Company has a license agreement with the Whitehead Institute for Biomedical Research (“WIBR”), as amended, under which the Company has been granted an exclusive, sublicensable, nontransferable license under certain patent families related to the development of the Company’s red blood cell therapies (as amended, the “WIBR License”). The Company is obligated to pay WIBR annual license maintenance fees of less than $0.1 million, as well as patent-related costs, including legal fees, and low single-digit royalties based on annual net sales of licensed products and licensed services by the Company and its sublicensees. Based on the progress the Company makes in the advancement of products covered by the licensed patent rights, the Company is required to make aggregate milestone payments of up to $1.6 million upon the achievement of specified preclinical, clinical and regulatory milestones. In addition, the Company is required to pay to WIBR a percentage of the non-royalty payments that it receives from sublicensees of the patent rights licensed by WIBR. This percentage varies from low single-digit to low double-digit percentages and will be based upon the clinical stage of the product that is the subject of the sublicense. Royalties shall be paid by the Company on a licensed product-by-licensed product and country-by-country basis, beginning on the first commercial sale of such licensed product in such country until expiration of the last valid patent claim covering such licensed product in such country.

The Company has the right to terminate the WIBR License in its entirety, on a patent-by-patent or country-by-country basis, at will upon three months’ notice to WIBR. WIBR may terminate the agreement upon breach of contract or in the event of the Company’s bankruptcy, liquidation, insolvency or cessation of business related to the license.

401(k) Plan

In January 2018, the Company established 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 pre-tax basis. The Company makes matching contributions at a rate of 50% of each employee’s contribution up to a maximum employee contribution of 6% of eligible plan compensation. For the three and nine months ended September 30, 2022, the Company made matching contributions of $0.2 million and $0.8 million, respectively.

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, contract research organizations, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and executive officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims.

Legal Proceedings

The Company is not currently party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses as incurred the costs related to such legal proceedings.

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Net Loss per Share

9 Months Ended

Sep. 30, 2022

Earnings Per Share [Abstract]

Net Loss per Share

Net Loss per Share

Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Numerator:
Net loss	$	(62,873)	$	(49,016)	$	(159,526)	$	(141,526)
Denominator:
Weighted average common shares outstanding, basic and diluted	90,364,222		89,807,383		90,262,487		87,240,694
Net loss per share, basic and diluted	$	(0.70)	$	(0.55)	$	(1.77)	$	(1.62)

The Company’s potential dilutive securities have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following potential common shares from the periods in the table above, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:

	September 30,
	2022	2021
Unvested restricted common stock	1,207,110	985,364
Stock options to purchase common stock	18,814,424	17,782,603
	20,021,534	18,767,967

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Restructuring and Impairment Charges

9 Months Ended

Sep. 30, 2022

Restructuring and Related Activities [Abstract]

Restructuring and Related Activities Disclosure

Restructuring and Impairment Charges

The Company estimates that it will incur approximately $30.6 million in costs to implement the Reorganization Plan, as described in Note 1. The actions associated with the Reorganization Plan commenced in September 2022 and are expected to be substantially completed by January 31, 2023.

As a result of these events, the Company incurred the following restructuring and impairment charges, which are recorded in the condensed consolidated statements of operations and comprehensive loss (in thousands):

	Three Months Ended September 30, 2022		Nine Months Ended September 30, 2022
Employee termination benefits	$	5,667	$	5,667
Impairment of property, plant and equipment	17,787		17,787
Contract termination costs	6,598		6,598
	$	30,052	$	30,052

Employee Termination Benefits

Employees affected by the reduction in workforce under the Company's Reorganization Plan obtained involuntary termination benefits that are provided pursuant to a one-time benefit arrangement. For employees who were notified of their termination in September 2022 and have no requirements to provide future service, the Company recognized the liability for the termination benefits in full at fair value in the current period. For employees who are required to render services beyond a minimum retention period to receive their one-time termination benefits, the Company is recognizing the termination benefits ratably over their future service periods. The service periods began in September 2022 and all will end at various dates through December 31, 2022. The Company expects that it will incur approximately $6.3 million of employee termination benefits expense to implement the Reorganization Plan.

The following table shows the liability related to employee termination benefits as of September 30, 2022:

	Employee Termination Benefits
Accrued employee termination benefits beginning balance	$	—
Employee termination benefits charges incurred during the period	5,667
Amounts paid or otherwise settled during the period	(763)
Accrued employee termination benefits as of September 30, 2022	$	4,904

Impairment of Property, Plant and Equipment

As a result of the Reorganization Plan, the Company determined that sufficient indicators exist to trigger the performance of an interim long-lived asset impairment analysis as of September 30, 2022. In the third quarter of 2022, the Company tested the recoverability of its asset group using entity-specific undiscounted cash flows. Based on these undiscounted cash flows, the Company concluded the undiscounted future cash flows expected to result from the use and eventual disposition of its long-lived assets were less than the carrying value of the asset group. Therefore, the Company measured the long-lived asset impairment as the amount by which the carrying value of the asset group exceeds its fair value. The loss was allocated to the long-lived assets of the group on a pro rata basis using the relative carrying amounts of those assets, except that the loss allocated to an individual long-lived asset of the group did not reduce the carrying value of that asset below its fair value. The fair value of the asset group was determined from a third-party commercial real estate appraisal which represents a Level 3 fair value measurement.

Additionally, in conjunction with its Reorganization Plan, the Company committed to a plan to actively sell specific assets within its asset group, primarily of its laboratory equipment and furniture and fixtures. The laboratory equipment and furniture and fixtures met all of the prescribed criteria required to classify it as held for sale. At September 30, 2022, $4.3 million of laboratory equipment and furniture and fixtures was classified as held for sale as current assets on the condensed consolidated balance sheet as the disposal is expected to be consummated within one year of the balance sheet date and the Company does not expect to use the sale proceeds to reduce any long-term borrowings. The sale is expected to be completed by January 31, 2023.

For the three and nine months ended September 30, 2022, the Company recorded impairment charges of $17.8 million. The long-lived asset impairment charge was recorded within restructuring and impairment charges on the condensed consolidated statements of operations and comprehensive loss and as a reduction to the related asset balances on the condensed consolidated balance sheets.

See Note 4 for property, plant and equipment, net and assets held for sale carrying amounts after the effects of impairment charges and held for sale reclassifications.

Contract Termination Costs

The discontinuation of the RTX-240 and RTX-224 clinical trials resulted in the termination of vendor contracts before the end of their term, as well as costs that continue to be incurred under certain contracts with no future economic benefit to the Company. The Company recognized these contract termination costs in full in the current period. During the three and nine months ended September 30, 2022, the Company incurred $6.6 million of contract termination costs, which it estimates to be the full amount of such costs to be incurred related to the Reorganization Plan.

The following table shows the liability related to contract termination costs as of September 30, 2022:

	Contract Termination Costs
Accrued contract termination costs	$	—
Contract termination costs incurred during the period	6,598
Amounts paid or otherwise settled during the period	(2,007)
Accrued contract termination costs as of September 30, 2022	$	4,591

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Subsequent Events

9 Months Ended

Sep. 30, 2022

Subsequent Events [Abstract]

Subsequent Events

Subsequent Events

Strategic Plan

On November 2, 2022, the Company announced that, in light of the Company’s financial condition, including the repayment and termination of its $75.0 million credit facility with SLR Investment Corp., and the early stage of its programs, its Board of Directors approved a plan to review strategic alternatives, including a sale or merger of the Company or one or more sales of its assets, and to significantly and immediately reduce its operations. In connection with the Strategic Plan, the Company has terminated 42 of its employees (representing 82% of its current employee base), leaving a core team of individuals to lead the strategic review process.

The Company expects that these measures will reduce its operating expenses with the goal of allowing the Company to pursue any viable strategic alternatives. As a result of the Plan, the Company estimates that it will incur charges of approximately $4.4 million in the fourth quarter of 2022, which include termination benefits principally comprised of severance payments.

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Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2022

Accounting Policies [Abstract]

Unaudited Interim Financial Information

Unaudited Interim Financial Information

The condensed consolidated balance sheet at December 31, 2021 was derived from audited financial statements but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of September 30, 2022 and for the three and nine months ended September 30, 2022 and 2021 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K for the year-ended December 31, 2021, on file with the SEC. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position as of September 30, 2022 and condensed consolidated results of operations for the three and nine months ended September 30, 2022 and 2021 and the condensed consolidated cash flows for the nine months ended September 30, 2022 and 2021 have been made. The Company’s condensed consolidated results of operations for the three and nine months ended September 30, 2022 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2022.

Use of Estimates

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the accrual of research and development expenses, the valuation of stock-based awards and the valuation of long-lived assets. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that

it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts and experience. Actual results may differ from those estimates or assumptions.

The full extent to which the ongoing COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, including clinical trials, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19. As of the date of issuance of these unaudited condensed consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update estimates, judgments or revise the carrying value of any assets or liabilities. Actual results may differ from those estimates or assumptions.

Concentrations of Credit Risk and of Significant Suppliers

Concentrations of Credit Risk and of Significant Suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company’s cash and cash equivalents, as of September 30, 2022, consisted of cash and money market accounts. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and raw materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services or the availability of raw materials.

Cash Equivalents

Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents.

Restricted Cash

Restricted Cash

As of September 30, 2022 and December 31, 2021, the Company maintained letters of credit for the benefit of the landlords of its leased properties totaling $1.6 million and $1.7 million, respectively. The Company was required to maintain separate cash balances of these amounts to secure the letters of credit. Related to these separate cash balances, the Company included $1.6 million in restricted cash (non-current) in its condensed consolidated balance sheet as of September 30, 2022. As of December 31, 2021, the Company included $0.1 million in prepaid expenses and other current assets and $1.6 million in restricted cash (non-current) in its condensed consolidated balance sheet.

Cash, cash equivalents and restricted cash presented in the accompanying condensed consolidated statement of cash flows was $105.5 million and $265.8 million for the nine months ended September 30, 2022 and 2021, respectively, of which $1.6 million and $1.7 million was restricted cash, respectively.

Fair Value Measurements

Fair Value Measurements

Certain assets and liabilities are carried at fair value under 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 and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. The carrying value of the Company’s long-term debt approximates its fair value due to its variable interest rate, which approximates a market interest rate.

Investments

Investments

The Company’s investments are classified as available-for-sale and are carried at fair value. Realized gains and losses and declines in value are based on the specific identification method and are included as a component of other income (expense), net in the condensed consolidated statements of operations and comprehensive loss. The Company classifies its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such investments are available for current operations.

The Company evaluates its investments with unrealized losses for impairment. When assessing investments for unrealized declines in value, the Company considers whether the decline in value is related to a credit loss or non-credit loss. For credit losses, the Company reduces the investment to fair value through an allowance for credit losses recorded to the balance sheet and corresponding charge to the statement of operations. The allowance for credit losses and corresponding impairment charge is adjusted each period for changes in fair value. For non-credit losses, the Company reduces the investment to fair value through a charge to the statement of comprehensive loss, reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. No such credit losses were recorded during the periods presented.

Assets Held for Sale, Impairment of Long-Lived Assets

Assets Held for SaleThe Company classifies its long-lived assets to be sold as held for sale in the period (i) the Company has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures a long-lived asset that is classified as held for sale at the lower of its carrying value or fair value, less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a long-lived asset until the date of sale. Upon designation as an asset held for sale, the Company stops recording depreciation and amortization expense on long-lived assets. The Company assesses the fair value of a long-lived asset, less any costs to sell, at each reporting period and until the asset is no longer classified as held for sale.Impairment of Long-Lived Assets Long-lived assets consist of property, plant and equipment and operating lease, right-of-use asset. 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 underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of 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 and eventual disposition 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.

Leases

Leases

At the inception of an arrangement as lessee or lessor, the Company determines whether the arrangement is or contains a lease. Operating lease cost is recognized over the lease term on a straight-line basis. Variable lease cost and short-term leases (lease terms less than 12 months) are recognized as incurred. For both lessee and lessor arrangements, variable lease payments are the amounts owed by the Company to a lessor that are not fixed, such as reimbursement for common area maintenance and utilities costs, and are expensed when incurred. When determining the lease term, the Company includes options to extend or terminate the lease when it is reasonably certain that it will exercise that option.

For lessee arrangements, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes its incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. Operating leases are recognized on the balance sheet as right-of-use assets, operating lease liabilities current and operating lease liabilities non-current.

The Company has elected the following lease policies at the inception of a lease: (1) for lessee and lessor arrangements within all asset classes, combine lease and non-lease components as a single component, with the lease expense recognized over the expected term on a straight-line basis and (2) for lessee arrangements, apply short-term lease exemption for all leases that qualify, where a right-of-use asset or lease liability will not be recognized for leases with terms of one year or less.

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Investments and Fair Value of Financial Assets and Liabilities (Tables)

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

Schedule of financial assets and liabilities measured at fair value on a recurring basis

The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):

	September 30, 2022
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. government money market funds	$	96,729	$	—	$	—	$	96,729
	$	96,729	$	—	$	—	$	96,729

	December 31, 2021
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S government money market funds	$	217,009	$	—	$	—	$	217,009
	$	217,009	$	—	$	—	$	217,009

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Property, Plant and Equipment, Net and Assets Held for Sale (Tables)

9 Months Ended

Sep. 30, 2022

Property, Plant and Equipment, Net [Abstract]

Schedule of property, plant and equipment, net

Property, plant and equipment, net and assets held for sale consisted of the following, after the effects of impairment charges and held-for-sale reclassifications (in thousands):

	September 30, 2022		December 31, 2021
Land	$	1,300	$	1,300
Manufacturing facility	25,469		33,203
Manufacturing equipment	7,329		8,831
Laboratory equipment	1,333		17,501
Computer equipment	2,160		2,645
Furniture and fixtures	17		1,281
Leasehold improvements	570		444
Construction-in-progress	—		4,181
	38,178		69,386
Less: Accumulated depreciation and amortization	(11,084)		(17,856)
	$	27,094	$	51,530
Assets held for sale	$	4,257	$	—

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Accrued Expenses and Other Current Liabilities (Tables)

9 Months Ended

Sep. 30, 2022

Payables and Accruals [Abstract]

Schedule of accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):

	September 30, 2022		December 31, 2021
Accrued employee compensation and benefits	$	2,507	$	7,451
Accrued external research and development expenses	1,185		2,713
Accrued manufacturing facility expenses	123		2,349
Accrued general and administrative expenses	780		889
Accrued employee termination benefits	4,904		—
Accrued contract termination costs	4,591		—
Other	605		670
	$	14,695	$	14,072

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Debt (Tables)

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Schedule of estimated future principal payments due

As of September 30, 2022, the estimated future principal payments due under the Loan Agreement were as follows (in thousands):

Year ending December 31,
2022 (three months ending December 31)	$	—
2023	—
2024	18,750
2025	37,500
2026 and thereafter	18,750
	$	75,000

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Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of allocation of share based compensation

The Company recorded stock-based compensation expense in the following expense categories of its condensed consolidated statements of operations and comprehensive loss (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development expenses	$	2,266	$	3,408	$	7,958	$	8,995
General and administrative expenses	1,532		4,781		9,141		17,433
	$	3,798	$	8,189	$	17,099	$	26,428

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Net Loss per Share (Tables)

9 Months Ended

Sep. 30, 2022

Earnings Per Share [Abstract]

Schedule of calculation of basic and diluted net loss per share attributable to common stockholders

Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Numerator:
Net loss	$	(62,873)	$	(49,016)	$	(159,526)	$	(141,526)
Denominator:
Weighted average common shares outstanding, basic and diluted	90,364,222		89,807,383		90,262,487		87,240,694
Net loss per share, basic and diluted	$	(0.70)	$	(0.55)	$	(1.77)	$	(1.62)

Schedule of dilutive securities excluded from computations of diluted weighted average shares outstanding

The Company excluded the following potential common shares from the periods in the table above, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:

	September 30,
	2022	2021
Unvested restricted common stock	1,207,110	985,364
Stock options to purchase common stock	18,814,424	17,782,603
	20,021,534	18,767,967

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Restructuring and Impairment Charges (Tables)

9 Months Ended

Sep. 30, 2022

Restructuring and Related Activities [Abstract]

Restructuring and Related Costs

As a result of these events, the Company incurred the following restructuring and impairment charges, which are recorded in the condensed consolidated statements of operations and comprehensive loss (in thousands):

	Three Months Ended September 30, 2022		Nine Months Ended September 30, 2022
Employee termination benefits	$	5,667	$	5,667
Impairment of property, plant and equipment	17,787		17,787
Contract termination costs	6,598		6,598
	$	30,052	$	30,052

Schedule of Restructuring Reserve by Type of Cost

The following table shows the liability related to employee termination benefits as of September 30, 2022:

	Employee Termination Benefits
Accrued employee termination benefits beginning balance	$	—
Employee termination benefits charges incurred during the period	5,667
Amounts paid or otherwise settled during the period	(763)
Accrued employee termination benefits as of September 30, 2022	$	4,904

The following table shows the liability related to contract termination costs as of September 30, 2022:

	Contract Termination Costs
Accrued contract termination costs	$	—
Contract termination costs incurred during the period	6,598
Amounts paid or otherwise settled during the period	(2,007)
Accrued contract termination costs as of September 30, 2022	$	4,591

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Nature of the Business and Basis of Presentation (Details) $ in Thousands					1 Months Ended	3 Months Ended						9 Months Ended
	Nov. 02, 2022 USD ($) employee	Oct. 13, 2022 USD ($)	Mar. 18, 2021 USD ($) shares	Jul. 20, 2018 USD ($) shares	Oct. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($) shares	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Nature of the business and basis of presentation
Proceeds from issuance of common stock												$ 0	$ 188,000
Cash and cash equivalents						$ 103,884						103,884		$ 225,848
Accumulated deficit						836,544						836,544		$ 677,018
Net loss						$ 62,873	$ 44,241	$ 52,412	$ 49,016	$ 50,180	$ 42,330	159,526	141,526
Net cash (used in) operating activities												$ (117,625)	$ (107,905)
Subsequent event | 2018 Credit facility
Nature of the business and basis of presentation
Repayments of long-term debt	$ 75,000	$ 75,700			$ 75,700
Subsequent event | 2022 Strategic Restructuring Plan
Nature of the business and basis of presentation
Restructuring and related cost, number of positions eliminated | employee	42
Restructuring and related cost, number of positions eliminated, period percent	82.00%
Common stock
Nature of the business and basis of presentation
Shares issued (in shares) | shares											6,896,552
Conversion of redeemable convertible preferred stock to common stock (in shares) | shares				51,845,438
IPO
Nature of the business and basis of presentation
Shares issued (in shares) | shares				12,055,450
Net proceeds after deducting underwriting discounts and commissions				$ 254,300
Overallotment
Nature of the business and basis of presentation
Shares issued (in shares) | shares				1,572,450
Offering
Nature of the business and basis of presentation
Shares issued (in shares) | shares			6,896,552
Net proceeds after deducting underwriting discounts and commissions			$ 187,200
Proceeds from issuance of common stock			$ 187,200

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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Restricted cash for the benefit of its leased properties	$ 1,600	$ 1,700
Restricted cash (non-current)	1,573	1,573
Restricted cash, current		100
Cash, cash equivalents and restricted cash	105,457	$ 227,583	$ 265,753	$ 92,901
Restricted cash	$ 1,600		$ 1,700

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Investments and Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Marketable securities
Investments		$ 0
Recurring
Marketable securities
Assets	$ 96,729	217,009
Recurring | Money Market Funds
Marketable securities
Cash equivalents	96,729	217,009
Recurring | Level 1
Marketable securities
Assets	96,729	217,009
Recurring | Level 1 | Money Market Funds
Marketable securities
Cash equivalents	96,729	217,009
Recurring | Level 2
Marketable securities
Assets	0	0
Recurring | Level 2 | Money Market Funds
Marketable securities
Cash equivalents	0	0
Recurring | Level 3
Marketable securities
Assets	0	0
Recurring | Level 3 | Money Market Funds
Marketable securities
Cash equivalents	$ 0	$ 0

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Property, Plant and Equipment, Net and Assets Held for Sale (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment, Net
Property, plant and equipment, gross	$ 38,178	$ 38,178	$ 69,386
Less: Accumulated depreciation and amortization	(11,084)	(11,084)	(17,856)
Property, plant and equipment, net	27,094	27,094	51,530
Assets held-for-sale, not part of disposal group	4,257	4,257	0
2022 Restructuring Plan
Property, Plant and Equipment, Net
Impairment charges	17,800	17,800
Land
Property, Plant and Equipment, Net
Property, plant and equipment, gross	1,300	1,300	1,300
Manufacturing facility
Property, Plant and Equipment, Net
Property, plant and equipment, gross	25,469	25,469	33,203
Manufacturing equipment
Property, Plant and Equipment, Net
Property, plant and equipment, gross	7,329	7,329	8,831
Laboratory equipment
Property, Plant and Equipment, Net
Property, plant and equipment, gross	1,333	1,333	17,501
Computer equipment
Property, Plant and Equipment, Net
Property, plant and equipment, gross	2,160	2,160	2,645
Furniture and fixtures
Property, Plant and Equipment, Net
Property, plant and equipment, gross	17	17	1,281
Leasehold improvements
Property, Plant and Equipment, Net
Property, plant and equipment, gross	570	570	444
Construction-in-progress
Property, Plant and Equipment, Net
Property, plant and equipment, gross	$ 0	$ 0	$ 4,181

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Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Accrued employee compensation and benefits	$ 2,507	$ 7,451
Accrued external research and development expenses	1,185	2,713
Accrued manufacturing facility expenses	123	2,349
Accrued general and administrative expenses	780	889
Other	605	670
Accrued expenses and other current liabilities	14,695	14,072
Employee termination benefits
Restructuring Cost and Reserve [Line Items]
Accrued restructuring expenses	4,904	0
Contract termination costs
Restructuring Cost and Reserve [Line Items]
Accrued restructuring expenses	$ 4,591	$ 0

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Debt (Details) $ in Thousands						1 Months Ended
	Nov. 02, 2022 USD ($)	Oct. 13, 2022 USD ($)	Jun. 22, 2021 USD ($)	Jun. 21, 2021	Dec. 21, 2018 USD ($) tranche	Oct. 31, 2022 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Sep. 30, 2022 USD ($)
Estimated future principal payments due
2022									$ 0
2023									0
2024									18,750
2025									37,500
2026 and thereafter									18,750
Total debt									$ 75,000
2018 Credit facility
Debt
Maximum amount outstanding					$ 75,000
Number of tranche | tranche					3
Debt instrument, covenant, minimum cash balance					$ 10,000
Debt default interest rate addition (as a percent)									0.0400
2018 Credit facility | Subsequent event
Debt
Repayments of long-term debt	$ 75,000	$ 75,700				$ 75,700
Term loan
Debt
Principal amount of each tranche of term loans					25,000
Borrowing					$ 25,000		$ 25,000	$ 25,000
Principal amount to be funded per tranche, second amendment, including additional limit
Debt
Principal amount			$ 35,000
2018 Credit facility amendment
Debt
Interest rate (as a percent)			5.50%
Prepayment fee in first year (as a percent)			1.00%
Prepayment fee in second year (as a percent)			0.50%
Prepayment fee in third year (as a percent)			0.25%
2018 Credit facility amendment | Lenders
Debt
Issuance costs			$ 200
2018 Credit facility amendment | Minimum
Debt
Variable interest rate (as a percent)			2.10%
2018 Credit facility amendment | One-month U.S. LIBOR
Debt
Variable interest rate (as a percent)			2.10%	0.00%

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Equity (Details) $ / shares in Units, $ in Millions		9 Months Ended
	Mar. 18, 2021 USD ($) shares	Sep. 30, 2022 vote $ / shares shares	Jul. 07, 2022 shares	Dec. 31, 2021 $ / shares shares	Aug. 01, 2019 USD ($)	Jul. 20, 2018 $ / shares shares
Equity
Number of votes per common share | vote		1
Shares authorized (in shares)						160,000,000
Common stock, authorized (in shares)		300,000,000	300,000,000	150,000,000		150,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.001		$ 0.001		$ 0.001
Preferred stock, share authorized (in shares)		10,000,000		10,000,000		10,000,000
Preferred stock, par value (in dollars per share) | $ / shares		$ 0.001		$ 0.001		$ 0.001
At the market offering
Equity
Aggregate offering price | $					$ 100.0
Shares issued (in shares)		0
Offering
Equity
Shares issued (in shares)	6,896,552
Net proceeds after deducting underwriting discounts and commissions | $	$ 187.2

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Stock-Based Compensation - Compensation expense (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Stock-based compensation expense
Stock-based compensation expense	$ 3,798	$ 8,189	$ 17,099	$ 26,428
Research and development expenses
Stock-based compensation expense
Stock-based compensation expense	2,266	3,408	7,958	8,995
General and administrative expenses
Stock-based compensation expense
Stock-based compensation expense	1,532	$ 4,781	$ 9,141	$ 17,433
Service based stock options
Stock-based compensation expense
Purchase of an aggregate shares of common stock (in shares)			4,104,403
Options exercise price (in dollars per share)			$ 4.37
Weighted average grant-date fair value (in dollars per share)			$ 2.98
Stock options
Stock-based compensation expense
Unrecognized compensation cost	$ 36,200		$ 36,200
Unrecognized compensation cost expected to be recognized over a weighted average period			2 years 3 months 18 days

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Commitments and Contingencies - Collaborative Arrangements and Non-collaborative Arrangement (Details) - WIBR $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement
Aggregate milestone payments	$ 1.6
License maintenance fees | Maximum
Collaborative Arrangements and Non-collaborative Arrangement
License costs	$ 0.1

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Commitments and Contingencies - Defined Contribution Plan (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Jan. 31, 2018	Sep. 30, 2022	Sep. 30, 2022
Commitments and Contingencies
Employer matching contribution (as a percent)	50.00%
Company matching contribution		$ 0.2	$ 0.8
Maximum
Commitments and Contingencies
Percentage of employee's gross pay match (as a percent)	6.00%

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Net Loss per Share - Weighted Average Shares (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net loss	$ (62,873)	$ (44,241)	$ (52,412)	$ (49,016)	$ (50,180)	$ (42,330)	$ (159,526)	$ (141,526)
Denominator:
Weighted-average common shares outstanding, basic (in shares)	90,364,222			89,807,383			90,262,487	87,240,694
Weighted-average common shares outstanding, diluted (in shares)	90,364,222			89,807,383			90,262,487	87,240,694
Net loss per share, basic (in dollars per share)	$ (0.70)			$ (0.55)			$ (1.77)	$ (1.62)
Net loss per share, diluted (in dollars per share)	$ (0.70)			$ (0.55)			$ (1.77)	$ (1.62)

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Net Loss per Share - Antidilutive Securities (Details) - shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of of diluted weighted average shares outstanding (in shares)	20,021,534	18,767,967
Unvested restricted common stock
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of of diluted weighted average shares outstanding (in shares)	1,207,110	985,364
Stock options to purchase common stock
Diluted net loss per share attributable to common stockholders
Antidilutive securities excluded from computation of of diluted weighted average shares outstanding (in shares)	18,814,424	17,782,603

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Restructuring and Impairment Charges - Restructuring and Impairment Charges (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2022 USD ($)
Restructuring Cost and Reserve [Line Items]
Disposal Group, Including Discontinued Operation, Assets	$ 4,300	$ 4,300
2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	30,600	30,600
Impairment charges	17,800	17,800
Employee termination benefits	30,052	30,052
Employee termination benefits | 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	6,300	6,300
Employee termination benefits	5,667	5,667
Impairment of property, plant and equipment | 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Employee termination benefits	17,787	17,787
Contract termination costs | 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Employee termination benefits	$ 6,598	$ 6,598

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Restructuring and Impairment Charges - Restructuring Reserve Activity (Details) - 2022 Restructuring Plan - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2022
Restructuring Reserve [Roll Forward]
Employee termination benefits	$ 30,052	$ 30,052
Employee termination benefits
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0
Employee termination benefits	5,667	5,667
Amounts paid or otherwise settled during the period	(763)
Balance at end of period	4,904	4,904
Contract termination costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0
Employee termination benefits	6,598	6,598
Amounts paid or otherwise settled during the period	(2,007)
Balance at end of period	$ 4,591	$ 4,591

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Subsequent Events (Details) $ in Millions			1 Months Ended	3 Months Ended
	Nov. 02, 2022 USD ($) employee	Oct. 13, 2022 USD ($)	Oct. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
2022 Strategic Restructuring Plan | Forecast
Subsequent Event [Line Items]
Employee termination benefits				$ 4.4
Subsequent event | 2018 Credit facility
Subsequent Event [Line Items]
Repayments of long-term debt	$ 75.0	$ 75.7	$ 75.7
Subsequent event | 2022 Strategic Restructuring Plan
Subsequent Event [Line Items]
Restructuring and related cost, number of positions eliminated | employee	42
Restructuring and related cost, number of positions eliminated, period percent	82.00%