10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

_____________________________________

FORM 10-Q

_____________________________________

(Mark One)

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

For the quarterly period ended September 30, 2023

OR

o 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: 001-38419

_____________________________________

Arcus Biosciences, Inc.

(Exact Name of Registrant as Specified in its Charter)

_____________________________________

Delaware	47-3898435
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
3928 Point Eden Way Hayward, California 94545
(Address of principal executive offices)

Registrant’s telephone number, including area code: (510) 694-6200

_____________________________________

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

Titles of Each Class	Trading Symbol(s)	Name of Each Exchange on which Registered
Common Stock, Par Value $0.0001 Per Share	RCUS	The New York Stock Exchange

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 x No o

Indicate by check mark whether the registrant has submitted electronically 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 x No o

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	x	Accelerated filer	o
Non-accelerated filer	o	Smaller reporting company	o
Emerging growth company	o

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. o

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

As of November 1, 2023, the registrant had 74,855,565 shares of common stock, $0.0001 par value per share, outstanding.

ARCUS BIOSCIENCES, INC.

TABLE OF CONTENTS

		Page
	RISK FACTOR SUMMARY	i
PART I.	FINANCIAL INFORMATION
Item 1.	Financial Statements	1
	Condensed Consolidated Statements of Operations	1
	Condensed Consolidated Statements of Comprehensive Loss	2
	Condensed Consolidated Balance Sheets	3
	Condensed Consolidated Statements of Stockholders’ Equity	4
	Condensed Consolidated Statements of Cash Flows	5
	Notes to Condensed Consolidated Financial Statements	6
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	19
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	26
Item 4.	Controls and Procedures	26
PART II.	OTHER INFORMATION
Item 1.	Legal Proceedings	27
Item 1A.	Risk Factors	27
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	57
Item 3.	Defaults Upon Senior Securities	57
Item 4.	Mine Safety Disclosures	57
Item 5.	Other Information	58
Item 6.	Exhibits	59
SIGNATURES		60

RISK FACTOR SUMMARY

The following is a summary of the key risks and uncertainties that make an investment in our securities speculative and risky. This does not contain all of the information that may be important to you, and you should read this summary together with the more detailed description risks related to an investment in our securities set forth in this report under "Part II. Item 1A. Risk Factors".

Risks Related to our Limited Operating History, Financial Position and Capital Requirements

•We have a history of operating losses, have never generated any revenue from product sales and anticipate that we will continue to incur significant losses for the foreseeable future.

•We may need to obtain additional funding to finance our operations and complete the development and any commercialization of our investigational products. If we do not receive substantial capital when needed, we may be forced to restrict our operations or delay, reduce or eliminate our product development programs.

Risks Related to the Discovery and Development of our Investigational Products

•Clinical drug development is a lengthy, expensive and uncertain process, if we are unable to develop, obtain regulatory approval for and commercialize our investigational products, or experience significant delays in doing so, our business will be materially harmed.

•The results of preclinical studies and early clinical trials are not always predictive of future results.

•Enrollment and retention of subjects in clinical trials is expensive and time consuming, can be made more difficult or rendered impossible by competing treatments, clinical trials of competing investigational products, geopolitical instability and public health epidemics, each of which could result in significant delays and additional costs in our product development activities, or in the failure of such activities.

•Preliminary and interim data from our clinical studies that we announce or publish from time to time could materially change due to audit and verification procedures or as more patient data become available.

•Serious adverse events, undesirable side effects or other unexpected properties of our investigational products may be identified during development or after approval, which could lead to the discontinuation of our clinical development programs, refusal by regulatory authorities to approve our investigational products or limitations on the use of our investigational products or revocation of any marketing authorizations or subsequent limitations on the use of our investigational products.

•If we are not successful in discovering, developing and commercializing investigational products that take advantage of different mechanisms of action to achieve superior outcomes relative to the use of single agents or other combination therapies, our ability to achieve our strategic objectives would be impaired.

•Development of combination therapies may present more or different challenges than other therapies.

•Failure to successfully develop, validate and obtain regulatory clearance or approval for any required companion diagnostics could prevent us from realizing the commercial potential of our investigational products.

Risks Related to Reliance on Third Parties, Manufacturing and Commercialization

•If our collaboration with Gilead is not successful, our business could be adversely affected.

•We rely on third parties to conduct our clinical trials, to manufacture and supply us with sufficient quantities of our investigational products, standard of care and comparator products used in our clinical trials, and to perform some of our research and preclinical studies. If these third parties do not satisfactorily carry out their contractual duties or fail to meet expected deadlines, our development programs may be delayed or subject to increased costs, each of which may have an adverse effect on our business and prospects.

•Even if we receive marketing approval, we may not be successful in commercializing our investigational products or obtaining coverage and reimbursement approval for a product from a government or other third-party payor, which coverage may be delayed or may not be sufficient to cover our costs.

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•Our investigational products may never be approved or commercialized outside the United States, which would limit our ability to realize their full market potential.

•Any investigational products for which we intend to seek approval as biologic products may face competition sooner than anticipated.

Risks Related to In-Licenses, Strategic Arrangements and Intellectual Property

•We are currently party to several in-license agreements under which we acquired rights to use, develop, manufacture and/or commercialize certain of our investigational products. If we breach our obligations under these agreements, we may be required to pay damages, lose our rights to these investigational products or both, which would adversely affect our business and prospects.

•If we are unable to obtain and maintain sufficient intellectual property protection for our investigational products, our competitors could develop and commercialize products similar or identical to ours, and our ability to successfully commercialize our products may be adversely affected.

•We may need to obtain additional licenses of third-party technology which may cause us to operate our business in a more costly or otherwise adverse manner than anticipated.

•We may become involved in lawsuits alleging that we have infringed the intellectual property rights of third parties or to protect or enforce our patents or other intellectual property, which litigation could affect our ability to develop or commercialize our investigational products.

•Changes in patent law in the United States and other jurisdictions could diminish the value of patents in general, thereby impairing our ability to protect our investigational products.

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

Risks Related to our Business Operations and Industry

•We expect to expand our business operations and, as a result, we may encounter difficulties in managing our growth, which could disrupt our operations.

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

•Our internal information technology systems, and those of the third parties upon which we rely, are subject to failure, security breaches and other disruptions, which could result in a material disruption of our investigational products’ development programs, jeopardize sensitive information, or prevent us from accessing critical information or result in a loss of our assets, and potentially expose us to notification obligations, loss, liability or reputational damage and otherwise adversely affect our business.

•Failure to comply with health and data protection laws and regulations could lead to government enforcement actions (which could include civil or criminal penalties), private litigation, and/or adverse publicity and could negatively affect our operating results and business.

•Changes in healthcare law and implementing regulations, as well as changes in healthcare policy, may impact our business in ways that we cannot currently predict, and may have a significant adverse effect on our business and results of operations.

ii

PART I—FINANCIAL INFORMATION

Item 1. Financial Statements

ARCUS BIOSCIENCES, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(In millions, except per share amounts)

(unaudited)

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenues:
License and development service revenue (Includes $18, $23, $54 and $48 from a related party)	$	22	$	23	$	58	$	48
Other collaboration revenue (Includes $10, $8, $28 and $25 from a related party)	10		10		28		30
Total revenues	32		33		86		78
Operating expenses:
Research and development (Net of recoveries of $22, $27, $89 and $93 from a related party)	82		77		247		208
General and administrative	30		26		88		76
Total operating expenses	112		103		335		284
Loss from operations	(80)		(70)		(249)		(206)
Non-operating income (expense):
Interest and other income, net	12		5		30		8
Effective interest on liability for sale of future royalties	(1)		—		(2)		(1)
Total non-operating income, net	11		5		28		7
Loss before income taxes	(69)		(65)		(221)		(199)
Income tax expense	(2)		—		(5)		(1)
Net loss	$	(71)	$	(65)	$	(226)	$	(200)
Net loss per share:
Basic and diluted	$	(0.94)	$	(0.90)	$	(3.07)	$	(2.78)
Shares used to compute net loss per share:
Basic and diluted	74.6		72.2		73.6		71.8

See accompanying notes.

1

ARCUS BIOSCIENCES, INC.

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS

(In millions)

(unaudited)

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Net loss	$	(71)	$	(65)	$	(226)	$	(200)
Other comprehensive income (loss)	1		(2)		4		(8)
Comprehensive loss	$	(70)	$	(67)	$	(222)	$	(208)

See accompanying notes.

2

ARCUS BIOSCIENCES, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(In millions, except per share amounts)

(unaudited)

	September 30, 2023		December 31, 2022
ASSETS
Current assets:
Cash and cash equivalents	$	184	$	206
Marketable securities	615		803
Receivable from collaboration partners ($22 and $39 from a related party)	52		39
Prepaid expenses and other current assets	31		19
Total current assets	882		1,067
Long-term marketable securities	151		129
Property and equipment, net	50		35
Other noncurrent assets ($6 and $2 from a related party)	108		114
Total assets	$	1,191	$	1,345
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
Accounts payable	$	17	$	20
Deferred revenue ($96 and $97 to a related party)	103		97
Other current liabilities	80		76
Total current liabilities	200		193
Deferred revenue, noncurrent ($309 and $355 to a related party)	326		355
Other noncurrent liabilities	145		140
Commitments
Stockholders’ equity:
Preferred stock, $0.0001 par value per share; 10.0 shares authorized; no shares issued and outstanding.	—		—
Common stock and additional paid-in capital: $0.0001 par value per share; 400.0 shares authorized; 74.8 shares in 2023 and 72.9 shares in 2022 issued and outstanding	1,291		1,206
Accumulated deficit	(768)		(542)
Accumulated other comprehensive loss	(3)		(7)
Total stockholders’ equity	520		657
Total liabilities and stockholders’ equity	$	1,191	$	1,345

See accompanying notes.

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ARCUS BIOSCIENCES, INC.

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY

(In millions)

(unaudited)

	Number of shares of common stock	Common stock and additional paid-in capital		Accumulated deficit		Accumulated other comprehensive loss		Total stockholders’ equity
Balance at December 31, 2021	70.8	$	1,118	$	(275)	$	(1)	$	842
Issuance of common stock in connection with our equity award programs	0.8	10		—		—		10
Stock-based compensation	—	17		—		—		17
Other comprehensive loss	—	—		—		(4)		(4)
Net loss	—	—		(68)		—		(68)
Balance at March 31, 2022	71.6	1,145		(343)		(5)		797
Issuance of common stock in connection with our equity award programs	0.5	4		—		—		4
Stock-based compensation	—	15		—		—		15
Other comprehensive loss	—	—		—		(2)		(2)
Net loss	—	—		(67)		—		(67)
Balance at June 30, 2022	72.1	1,164		(410)		(7)		747
Issuance of common stock in connection with our equity award programs	0.3	3		—		—		3
Stock-based compensation	—	16		—		—		16
Other comprehensive loss	—	—		—		(2)		(2)
Net loss	—	—		(65)		—		(65)
Balance at September 30, 2022	72.4	$	1,183	$	(475)	$	(9)	$	699
Balance at December 31, 2022	72.9	$	1,206	$	(542)	$	(7)	$	657
Issuance of common stock in connection with our equity award programs	0.2	1		—		—		1
Stock-based compensation	—	19		—		—		19
Other comprehensive gain	—	—		—		3		3
Net loss	—	—		(80)		—		(80)
Balance at March 31, 2023	73.1	1,226		(622)		(4)		600
Issuance of common stock (see Note 3, Related party - Gilead Sciences, Inc.)	1.0	20		—		—		20
Issuance of common stock in connection with our equity award programs	0.4	3		—		—		3
Stock-based compensation	—	18		—		—		18
Net loss	—	—		(75)		—		(75)
Balance at June 30, 2023	74.5	1,267		(697)		(4)		566
Issuance of common stock	0.2	5		—		—		5
Issuance of common stock in connection with our equity award programs	0.1	1		—		—		1
Stock-based compensation	—	18		—		—		18
Other comprehensive gain	—	—		—		1		1
Net loss	—	—		(71)		—		(71)
Balance at September 30, 2023	74.8	$	1,291	$	(768)	$	(3)	$	520

See accompanying notes.

4

ARCUS BIOSCIENCES, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(In millions)

(unaudited)

	Nine Months Ended September 30,
	2023		2022
Cash flows from operating activities
Net loss	$	(226)	$	(200)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Stock-based compensation expense	55		48
Depreciation and amortization	5		5
Noncash lease expense	6		6
Amortization of premiums (discounts) on marketable securities	(13)		2
Other items, net	2		3
Changes in operating assets and liabilities:
Receivable from collaboration partners ($17 and $718 from a related party)	15		716
Other assets (($4) and ($2) from a related party)	(12)		(4)
Accounts payable	(3)		—
Deferred revenue (($47) and ($73) to a related party)	(51)		(78)
Other liabilities	4		10
Net cash provided by (used in) operating activities	(218)		508
Cash flows from investing activities
Purchases of marketable securities	(673)		(1,085)
Proceeds from maturities of marketable securities	837		491
Proceeds from sales of marketable securities	20		143
Purchases of property and equipment	(18)		(6)
Purchases of in-process research and development	—		(6)
Collaboration reimbursements of in-process research and development	—		3
Net cash provided by (used in) investing activities	166		(460)
Cash flows from financing activities
Proceeds from issuance of common stock ($20 and $— from a related party)	25		—
Proceeds from issuance of common stock pursuant to equity award plans	5		17
Proceeds from sale of future royalties	—		5
Net cash provided by financing activities	30		22
Net increase (decrease) in cash, cash equivalents and restricted cash	(22)		70
Cash, cash equivalents and restricted cash at beginning of period	209		151
Cash, cash equivalents and restricted cash at end of period	$	187	$	221
Non-cash investing and financing activities:
Unpaid portion of property and equipment purchases included in Accounts payable and Other current liabilities	$	6	$	1

See accompanying notes.

5

ARCUS BIOSCIENCES, INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited)

Note 1. Organization, liquidity and capital resources

Organization

Arcus Biosciences, Inc. (referred to as "Arcus," "we," "our," "us," or the "Company") is a clinical-stage, biopharmaceutical company focused on creating best-in-class therapies. Using our robust and highly efficient drug discovery capability, we have created a significant portfolio of investigational products which are in clinical development, with our most advanced molecule, an anti-TIGIT antibody, now in four Phase 3 registrational studies targeting lung and gastrointestinal cancers. Our deep portfolio of novel small molecules and enabling antibodies allows us to create highly differentiated therapies, which we are developing to treat multiple large indications.

We operate and manage our business as one reportable and operating segment, which is the business of developing and commercializing highly differentiated therapies that have a meaningful impact on patients.

Liquidity and Capital Resources

As of September 30, 2023, we had cash, cash equivalents and marketable securities of $950 million, which we believe will be sufficient to fund our planned operations for a period of at least twelve months following the date of filing of this report.

Note 2. Summary of significant accounting policies

Basis of Presentation

These interim financial statements should be read in conjunction with the audited Consolidated Financial Statements and the related notes thereto for the year ended December 31, 2022 included in our Annual Report on Form 10-K filed with the SEC on February 28, 2023. There have been no significant changes to our accounting policies as described in Note 2, Summary of significant accounting policies, in the notes to Consolidated Financial Statements in Item 8 of Part II of the Form 10-K.

These interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and include all adjustments consisting of normal recurring adjustments that management believes are necessary for a fair presentation of the periods presented. The Condensed Consolidated Balance Sheet as of December 31, 2022 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements.

Operating results for the nine months ended September 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023 or for any future period.

Use of Estimates

The preparation of the Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and related disclosures. We base our estimates on historical experience and on various market-specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Estimates are assessed and updated each period to reflect current information. Actual results may differ materially from those estimates.

Recent Accounting Pronouncements

There have been no new accounting pronouncements issued or adopted during the period with a significant impact to our financial statements.

6

Note 3. Related party - Gilead Sciences, Inc.

In 2020, we and Gilead Sciences, Inc. (Gilead) entered into an Option, License and Collaboration Agreement (the Gilead Collaboration Agreement), Common Stock Purchase Agreement (the Stock Purchase Agreement), and Investor Rights Agreement (Investor Rights Agreement). In 2021, we amended the Gilead Collaboration Agreement (the First Gilead Collaboration Agreement Amendment) and the Stock Purchase Agreement (the First Stock Purchase Agreement Amendment), and in 2022 we amended the Investor Rights Agreement (Amended Investor Rights Agreement). In the second quarter of 2023, we expanded our collaboration to include research-stage inflammation programs (the Second Gilead Collaboration Agreement Amendment) and further amended the Stock Purchase Agreement (the Second Stock Purchase Agreement Amendment). We refer to these agreements collectively as the Gilead Agreements.

Stock Purchase Agreement and Investor Rights Agreement

In 2020, under the Stock Purchase Agreement, Gilead purchased 6.0 million shares of our common stock for a total cost of $200 million, of which $91 million was allocated to the revenue related performance obligations created by the Gilead Collaboration Agreement (See Note 5, Revenues for more information).

In 2021, under the First Stock Purchase Agreement Amendment, Gilead purchased 5.7 million shares of our common stock for a total cost of $220 million.

In June 2023, under the Second Stock Purchase Agreement Amendment, Gilead purchased 1.0 million shares of our common stock for a total cost of $20 million.

Gilead has the right, at its option until July 2025, to purchase up to a maximum of 35% of the Company’s then-outstanding voting common stock, at a purchase price equal to the greater of a 20% premium to market (based on a trailing five-day average closing price at option exercise) or the $33.54 initial purchase price. Based on the value of our common stock at each contract closing, the right to purchase additional shares had no value.

Under the Investor Rights Agreement, Gilead has the right, which they have exercised, to designate two members of our Board of Directors. This agreement also included a three-year standstill and a two-year lockup, provided Gilead with registration rights commencing at the end of the lockup period and provides Gilead with pro rata participation rights in certain future financings. In October 2022, we registered Gilead’s shares and entered into the Amended Investor Rights Agreement, primarily to extend the two-year lockup period to three-years which expired on July 13, 2023.

As of September 30, 2023, Gilead held approximately 19.8% of the Company’s outstanding common stock arising from purchases in our May 2020 public offering and purchases under the Stock Purchase Agreement and the First and Second Amended Stock Purchase Agreements.

Collaboration Agreements

In 2020, we entered into the Gilead Collaboration Agreement, which gave Gilead an exclusive license to develop and commercialize zimberelimab (the anti PD-1 program) in certain markets and time-limited options to acquire exclusive licenses to develop and commercialize any of our then-current and future clinical programs arising during the 10-year collaboration term, contingent upon $100 million option continuation payments payable on each of the second, fourth, sixth and eighth anniversaries of the agreement. Upon closing of the transaction in July 2020, Gilead made an upfront payment of $175 million.

In 2021, we entered into the First Gilead Collaboration Agreement Amendment pursuant to which Gilead exercised its option to three programs—providing Gilead with exclusive licenses to develop and commercialize domvanalimab and AB308 (collectively, the anti-TIGIT program), etrumadenant (the adenosine receptor antagonist program) and quemliclustat (the CD73 program), in certain markets—for a total payment of $725 million that was received in 2022. The amendment also (i) provided for a slight reduction in the royalties for these three programs, such that Gilead will pay us tiered royalties as a percentage of revenues ranging from the mid-teens to the low twenties; and (ii) removed the $100 million option continuation payment that was otherwise due on the second anniversary of the Gilead Collaboration Agreement.

Gilead's option, on a program-by-program basis, will expire after a prescribed period following the achievement of a clinical development milestone in such program and our delivery to Gilead of the requisite data package. Gilead may exercise its option to any program at any time prior to expiration of the option and will pay Arcus an option fee of $150 million per program. With respect to domvanalimab, we are also eligible to receive up to $500 million in potential U.S. regulatory approval milestones.

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For each program that Gilead opts in to, both companies will co-develop and equally share global development costs, subject to certain opt-out rights that we have, and caps on our spending and related subsequent adjustments. For each program, provided we have not exercised our opt-out rights, we have the option to co-promote in the United States with equal sharing of related profits and losses. Gilead has the right to exclusively commercialize outside of the U.S., subject to the rights of our existing partners in any territories and will pay us tiered royalties as a percentage of revenues ranging from the high teens to the low twenties.

Under the First Gilead Collaboration Agreement Amendment, Gilead also has option rights to two immuno-oncology research programs for which we will lead discovery and early development activities. With respect to these two research programs, Gilead has the right to exercise its option, on a program-by-program basis, either (i) upon our completion of certain IND-enabling activities for an option payment of $60 million or (ii) following the achievement of a clinical development milestone for an option payment of $150 million. These research programs were not determined to be performance obligations at contract inception, due to the very early stages of the programs.

In May 2023, we entered into the Second Gilead Collaboration Agreement Amendment pursuant to which we expanded our collaboration to provide Gilead with options to license up to four jointly selected research-stage programs that target inflammatory diseases for which we will lead discovery and early development activities. We will receive an upfront payment of $17.5 million for each initiated program and Gilead will have an option to license each program at two separate, prespecified time points. For the first two research programs, Gilead has the right to exercise its option, on a program-by-program basis, either (i) upon our completion of certain IND-enabling activities for an option payment of $45 million or (ii) following the achievement of a clinical development milestone for an option payment of $150 million. If Gilead exercises its option at the earlier time point for the first two programs, we would be eligible to receive up to $375 million in regulatory and commercial milestone payments as well as tiered royalties for each optioned program. For any other program option exercise by Gilead, the parties would have rights to co-develop and share global development costs and to co-commercialize and share profits in the US for that program. We received a total upfront payment of $35 million for an initial two research programs in June 2023.

As of September 30, 2023, Gilead has licenses to domvanalimab, AB308, etrumadenant, quemliclustat and zimberelimab.

For the three months ended September 30, 2023 and 2022, we recognized revenue under the Gilead Agreements of $28 million and $31 million, respectively, and net reimbursements from Gilead recognized as reductions in research and development (R&D) expense of $22 million and $27 million, respectively. For the nine months ended September 30, 2023 and 2022, we recognized revenue under the Gilead Agreements of $82 million and $73 million, respectively, and net reimbursements from Gilead recognized as reductions in R&D expense of $89 million and $93 million, respectively.

For a more detailed discussion on revenues recognized under the Gilead Agreements, see Note 5, Revenues.

Note 4. License and collaborations

We enter into licensing agreements, strategic collaborations and other similar arrangements with third parties for the development and commercialization of certain investigational products. These arrangements may be collaborative and involve two or more parties who are active participants in the operating activities of the collaboration and are exposed to significant risks and rewards depending on the commercial success of the activities. These arrangements may include: non-refundable upfront payments; payments for options to acquire certain rights; potential development and regulatory milestone payments and/or sales-based milestone payments; royalty payments; revenue or profit-sharing arrangements; expense reimbursements; and cost-sharing arrangements.

Operating expenses for costs incurred pursuant to these arrangements are reported in their respective expense line items in the Condensed Consolidated Statements of Operations, net of any payments due to or reimbursements due from our collaboration partners, with such reimbursements being recognized at the time the party becomes obligated to pay.

Our significant arrangements are discussed below.

Gilead Collaboration

See Note 3, Related party - Gilead Sciences, Inc.

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Taiho Collaboration

In 2017, we entered into an agreement with Taiho Pharmaceutical Co., Ltd (Taiho) under which we granted Taiho exclusive options to programs arising over a five-year period which ended in September 2022 (the Option Period) for an upfront payment of $35 million. Upon an option exercise of a program, Taiho would obtain exclusive development and commercialization rights to investigational products under the program for Japan and certain other territories in Asia (excluding China) (the Taiho Territory).

For each option that Taiho exercises, they will be obligated to make a payment of $3 million to $15 million, depending on the development stage of the optioned program. Upon exercise, Taiho is solely responsible for continued development and commercialization in the Taiho Territory. In addition, for each optioned program we would be eligible to receive clinical and regulatory milestones of up to $130 million and commercial milestone payments of up to $145 million with the achievement of certain sales thresholds in the Taiho Territory. We will also receive royalties ranging from high single-digits to mid-teens on net sales of licensed products in the Taiho Territory. Royalties will be payable by product and country commencing on the first commercial sale and ending upon the later of: (a) 10 years; and (b) expiration of the last-to-expire valid claim of our patents covering the manufacture, use or sale.

During the fourth quarter of 2022, Taiho opted to participate in two global Phase 3 trials of domvanalimab and zimberelimab combinations, STAR-121 and STAR-221, and is obligated to make certain milestone payments contingent upon successfully satisfying the related clinical milestones. During the three months ended September 30, 2023, the clinical milestones for domvanalimab and zimberelimab for the STAR-221 study were met and Taiho became obligated to pay us $28 million.

As of September 30, 2023, Taiho has licenses for the Taiho Territory to (i) etrumadenant (the adenosine receptor antagonist program); (ii) zimberelimab (the anti PD-1 program); and (iii) domvanalimab and AB308 (collectively, the anti-TIGIT program).

For the three months ended September 30, 2023 and 2022, we recognized revenue of $4 million and $2 million, respectively, and we recognized net reimbursements from Taiho as a reduction in R&D expense of $2 million for the three months ended September 30, 2023. For the nine months ended September 30, 2023 and 2022, we recognized revenue of $4 million and $5 million, respectively and we recognized net reimbursements from Taiho as a reduction in R&D expense of $4 million for the nine months ended September 30, 2023. For a more detailed discussion on revenues see Note 5, Revenues.

AstraZeneca Collaboration

In 2020, we entered into a collaboration with AstraZeneca to evaluate domvanalimab, our investigational anti-TIGIT antibody, in combination with AstraZeneca’s durvalumab in a registrational Phase 3 clinical trial in patients with unresectable Stage 3 non-small cell lung cancer (NSCLC), known as the PACIFIC-8 trial. Under the collaboration, each company will retain existing rights to their respective molecules and any future commercial economics. AstraZeneca will conduct the trial, and each company will supply their respective investigational product to support the trial. Under the terms of the agreement, we will reimburse AstraZeneca for its share of the trial costs upon the achievement of certain milestones or under certain circumstances if the agreement is terminated early. The portion of the costs that we consider to be unavoidable are accrued in advance of the achievement of the milestone.

For the three months ended September 30, 2023 and 2022, we recognized as R&D expense $1 million and $1 million, respectively, before expected recoveries from our cost-sharing agreement with Gilead. For the nine months ended September 30, 2023 and 2022, we recognized as R&D expense $6 million and $3 million, respectively, before expected recoveries from our cost-sharing agreement with Gilead. At September 30, 2023 and December 31, 2022, we have recognized a liability of $11 million and $5 million, respectively, related to our obligation to AstraZeneca which is recorded in Other noncurrent liabilities.

The PACIFIC-8 trial forms part of the Arcus and Gilead joint development program for domvanalimab and our portion of the trial costs are shared with Gilead. At September 30, 2023 and December 31, 2022, we have recognized a receivable due from Gilead for these shared costs of $6 million and $2 million, respectively, which is recorded in Other noncurrent assets.

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WuXi Biologics License - anti-PD-1

In 2017, we entered into an agreement with WuXi Biologics Ireland Limited (WuXi Biologics) which, as amended, provides us with exclusive rights to (i) develop, use and manufacture products that include an anti-PD-1 antibody, including zimberelimab, worldwide and (ii) commercialize any such products worldwide, except in Greater China. Under the agreement, as of September 30, 2023, we may incur (i) clinical and regulatory milestone payments, and commercialization milestone payments of up to $375 million, (ii) tiered royalties that range from the high single-digits to low teens on net sales of the licensed products and (iii) fees related to any sublicenses.

For the three and nine months ended September 30, 2023 and 2022, we did not have any transactions nor were any amounts due under this arrangement.

WuXi Biologics License - anti-CD39

In 2020, we entered into an agreement with WuXi Biologics, under which we obtained the exclusive worldwide license to develop and commercialize anti-CD39 antibodies discovered under the agreement. As of September 30, 2023, we may incur additional clinical and regulatory milestone payments of up to $14 million and royalty payments in the low single digits on net sales of the licensed products under this agreement.

For the three months ended September 30, 2023 and 2022, we incurred no development milestones nor were any amounts due under this arrangement. For the nine months ended September 30, 2023 and 2022, we incurred development milestones under this arrangement of $1 million and $2 million, respectively, which were recognized as R&D expense.

Abmuno License

In 2016, we entered into an agreement with Abmuno Therapeutics LLC (Abmuno), under which we obtained the exclusive worldwide license to develop, use, manufacture, and commercialize products that include an anti-TIGIT antibody, including domvanalimab. As of September 30, 2023 we may incur additional clinical, regulatory and commercialization milestone payments of up to $88 million under this agreement.

For the three and nine months ended September 30, 2023 and 2022, we did not have any transactions nor were any amounts due under this arrangement.

Note 5. Revenues

The following table summarizes our revenues by collaboration, category of revenue, and the method of recognition (in millions):

			Three Months Ended September 30,				Nine Months Ended September 30,
	Over time	Point in time	2023		2022		2023		2022
Gilead Collaboration
License and R&D services	*		$	20	$	23	$	57	$	48
Access rights	*		8		8		25		25
Taiho Collaboration
R&D services	*		4		—		4		—
Access rights	*		—		2		—		5
Total revenues			$	32	$	33	$	86	$	78

Revenues from Gilead accounted for 88% and 94% of Total revenues for the three months ended September 30, 2023 and 2022, respectively and 95% and 94% for the nine months ended September 30, 2023 and 2022, respectively.

The following table summarizes the revenue recognized as a result of changes in the deferred revenue balance (in millions):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue recognized from amounts included in deferred revenue at the beginning of the period	$	28	$	33	$	79	$	78

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Revenue for the nine months ended September 30, 2023 includes a net $1 million cumulative catch-up of revenue due to changes in the total estimated effort to be incurred in the future to satisfy the Gilead license and R&D services performance obligations, primarily related to lower estimated late-stage clinical trial costs for etrumadenant, partially offset by higher estimated late-stage clinical trial costs for quemliclustat.

We had $429 million and $452 million of deferred revenue remaining on our Condensed Consolidated Balance Sheets at September 30, 2023 and December 31, 2022, respectively, allocated between current and noncurrent based on the expected timing of future recognition.

Revenue from the Gilead Collaboration

Activity for performance obligations under this arrangement for the periods presented herein was as follows:

Inflammation Programs - R&D Services

In May 2023, we entered into the Second Gilead Collaboration Agreement Amendment pursuant to which we expanded our collaboration to provide Gilead with options to license up to four jointly selected research-stage programs that target inflammatory diseases for which we will lead discovery and early development activities (see Note 3, Related party - Gilead Sciences, Inc., for more information). In June 2023, we received a total upfront payment of $35 million for an initial two jointly selected research-stage programs. We determined that the Second Gilead Collaboration Agreement Amendment represented a separate contract and, at the amendment closing date, we allocated the transaction price of $35 million to the performance obligations created as of the date of this amendment. The following table summarizes the allocation of the transaction price to the distinct performance obligations (in millions):

Allocation to performance obligations	Distinct	Amount
Inflammation target 1	*	$	18
Inflammation target 2	*	17
Total allocated transaction price		$	35

We determined that we have separate performance obligations to perform R&D services for Gilead related to discovery and early development activities for each research program for which they have made an upfront payment. The standalone selling price of these obligations was determined using an expected cost-plus margin approach. We recognize the amounts allocated to these services as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program. The options to acquire additional licenses or services did not result in additional performance obligations because they did not provide a material right at contract inception, primarily due to the very early stages of the programs.

We recognized revenue of $2 million and $3 million for the three and nine months ended September 30, 2023, respectively, within Other collaboration revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $32 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to these performance obligations.

Etrumadenant - License and R&D Services

Under the First Gilead Collaboration Agreement Amendment, Gilead has an exclusive license and we are also obligated to perform further R&D services for Gilead related to etrumadenant. We determined that the license and R&D services were combined based on an evaluation of the delivery of the license, due to the early stage of the technology and the specialized nature of our know-how. We allocated arrangement consideration of $219 million to the combined license and R&D services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized revenue of $21 million and $3 million for the three months ended September 30, 2023 and 2022, respectively, and $39 million and $21 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $146 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation.

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Quemliclustat - License and R&D Services

Under the First Gilead Collaboration Agreement Amendment, Gilead has an exclusive license and we are also obligated to perform further R&D services for Gilead related to quemliclustat. We determined that the license and R&D services were combined based on an evaluation of the delivery of the license, due to the early stage of the technology and the specialized nature of our know-how. We allocated arrangement consideration of $176 million to the combined license and R&D services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized a reversal of revenue of $4 million for the three months ended September 30, 2023 due to changes in the total estimated effort to be incurred in the future to satisfy the performance obligations, primarily related to revised clinical trial assumptions and revenue of $12 million for the three months ended September 30, 2022. We recognized revenue of $11 million and $16 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $138 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation.

Domvanalimab - R&D Services

Under the First Gilead Collaboration Agreement Amendment, we have an obligation to perform further R&D services for Gilead related to domvanalimab. We determined that these services are distinct based on an evaluation of the delivery of the related license, noting that the program was in the later stages of development and license met the criteria for being distinct from the R&D services required. We allocated arrangement consideration of $34 million to the R&D services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized revenue of $1 million for the three months ended September 30, 2023, and $3 million and $2 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $27 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation.

Zimberelimab - R&D and Commercialization Services

Under the First Gilead Collaboration Agreement Amendment, we have an obligation to perform further R&D and commercialization services for Gilead related to zimberelimab, as a monotherapy and in combination with other agents. We determined that these services are distinct based on an evaluation of the delivery of the related license, noting that the program was in the later stages of development and license met the criteria for being distinct from the R&D and commercialization services required. We allocated arrangement consideration of $11 million to the R&D and commercialization services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized no revenue for the three months ended September 30, 2023 and $8 million for the three months ended September 30, 2022. We recognized $1 million and $9 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. As of December 31, 2022, substantially all the revenue related to this performance obligation had been recognized.

Access Rights and Option Continuation Periods

Under the First Gilead Collaboration Agreement Amendment, Gilead has exclusive access to our current programs as well as the future programs for a period of ten years, contingent upon option continuation payments totaling $300 million, consisting of a $100 million payment on each of the fourth, sixth, and eighth anniversaries of the agreement. We allocated arrangement consideration of $121 million to this performance obligation.

We use a time-elapsed input method to measure progress toward satisfying this obligation, which is the method we believe most faithfully depicts our performance in transferring the promised services during the time period in which Gilead has access to our R&D pipeline. Accordingly, the revenue allocated to this performance obligation is being recognized using this input method over the minimum four-year period. We have determined that Gilead is not obligated to pay the remaining $300 million due over the remainder of the term and excluded these payments from the transaction price. Failure to pay the non-obligatory option continuation payments will result in Gilead’s loss of certain rights to access and obtain licenses to the programs arising from our R&D pipeline.

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We recognized revenue of $8 million associated with the performance of this obligation for each of the three months ended September 30, 2023 and 2022, and $25 million for each of the nine months ended September 30, 2023 and 2022, within Other collaboration revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $62 million of deferred revenue on our Condensed Consolidated Balance Sheet related to this performance obligation.

Revenue from the Taiho Collaboration

In September 2023, under the Taiho collaboration, certain clinical milestones for domvanalimab and zimberelimab were met through the STAR-221 study and Taiho became obligated to pay us $28 million, which is recorded in Receivable from collaboration partners at September 30, 2023 on our Condensed Consolidated Balance Sheet. We determined that we have a performance obligation to perform R&D services for Taiho related to the global development activities for the STAR-221 study in support of the Taiho Territory. We allocated the $28 million to this single performance obligation and recognize the amounts allocated to this service as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the programs.

We recognized revenue of $4 million for both the three and nine months ended September 30, 2023 within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $24 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation, allocated between current and noncurrent based on the expected timing of future recognition.

Capitalized Costs to Obtain Contracts

We incurred certain costs to obtain the Gilead Collaboration Agreement in 2020 and the First Gilead Collaboration Agreement Amendment in 2021, which consisted of consultant and legal fees. We allocated these costs to the various performance obligations, to be recognized as the underlying performance obligations are satisfied and revenue is recognized.

For the three months ended September 30, 2023 and 2022, the recognized expense was not significant. For each of the nine months ended September 30, 2023 and 2022, we recognized $1 million expense related to these capitalized costs in G&A expense. At September 30, 2023, we had $3 million in capitalized costs to obtain the contracts, of which $1 million was recorded as Prepaid expenses and other current assets and $2 million was recorded as Other noncurrent assets in our Condensed Consolidated Balance Sheet.

Note 6. Income taxes

The income tax provision or benefit for interim periods is determined using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into consideration in the relevant period. Each quarter, we update the estimate of the annual effective tax rate, and if the estimated tax rate changes, we record a cumulative adjustment to the provision or benefit.

The income tax expense was $2 million for the three months ended September 30, 2023, with an effective tax rate of (2.4%). We did not record a provision for income taxes for the three months ended September 30, 2022. The income tax expense was $5 million and $1 million for the nine months ended September 30, 2023 and 2022, with an effective tax rate of (2.2%) and (0.5%), respectively. The year-over-year increase in the income tax provision was due to an increase in taxable income. We have taxable income compared to book losses before income taxes due to the timing of recognition of deferred revenue for tax purposes and the effects of the mandatory capitalization and amortization of research and development expenses starting in 2022, as required by the 2017 Tax Cuts and Jobs Act. The effective tax rate differs from the U.S. statutory tax rate primarily due to the valuation allowances on our deferred tax assets and state income taxes.

As of September 30, 2023 and December 31, 2022, we have provided a valuation allowance against U.S. federal and state deferred tax assets. We continue to evaluate the realizability of deferred tax assets and the related valuation allowance. If our assessment of the deferred tax assets or the corresponding valuation allowance were to change, we would record the related adjustment to income during the period in which we make the determination.

We recognize interest and penalties associated with uncertain tax benefits as part of the income tax provision. To date, we have not recognized any interest and penalties, nor have we accrued for or made payments for interest and penalties.

We have not been audited by the Internal Revenue Service, or any state or foreign tax authority. We are subject to taxation in the United States and in Australia. Due to net operating loss and research credit carryforwards, all of our tax years, from 2015 to 2022, remain open to U.S. federal and California state tax examinations. In addition, our fiscal years from 2018 to 2022 are open to examination in Australia.

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Note 7. Net loss per share

The following table summarizes potentially dilutive securities excluded from the computation of diluted net loss per share calculations because they would have been antidilutive (in millions):

	September 30, 2023	September 30, 2022
Common stock options issued and outstanding	13.7	12.3
Restricted stock units issued	1.9	1.4
Employee Stock Purchase Plan shares	0.2	0.1
Total potential dilutive securities	15.8	13.8

We have also excluded the effect of Gilead’s right to purchase additional shares of our common stock from the calculation as these rights had no intrinsic value at either September 30, 2023 or 2022.

Note 8. Stock-based compensation

The following table reflects the components of stock-based compensation expense recognized in our Condensed Consolidated Statements of Operations (in millions):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	8	$	8	$	26	$	24
General and administrative	10		8		29		24
Total stock-based compensation	$	18	$	16	$	55	$	48

Note 9. Cash, cash equivalents and marketable securities

The following table summarizes the amortized cost, gross unrealized gains and losses and the fair value of our cash, cash equivalents and marketable securities, all of which are considered available for sale, by type of securities (in millions):

Types of securities as of September 30, 2023	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Money market funds	$	110	$	—	$	—	$	110
U.S. treasury securities	246		—		(1)		245
Corporate securities and commercial paper	493		—		(2)		491
U.S. government agency securities	96		—		—		96
Certificate of deposit	8		—		—		8
Total cash, cash equivalents and marketable securities	$	953	$	—	$	(3)	$	950

Types of securities as of December 31, 2022	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Money market funds	$	169	$	—	$	—	$	169
U.S. treasury securities	317		—		(3)		314
Corporate securities and commercial paper	635		—		(4)		631
U.S. government agency securities	20		—		—		20
Certificate of deposit	4		—		—		4
Total cash, cash equivalents and marketable securities	$	1,145	$	—	$	(7)	$	1,138

The following table summarizes the fair values of our cash, cash equivalents and marketable securities by location in the Condensed Consolidated Balance Sheets and contractual maturity (in millions):

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Location in Condensed Consolidated Balance Sheets	Contractual Maturity	September 30, 2023		December 31, 2022
Cash and cash equivalents	-	$	184	$	206
Marketable securities	Within one year	615		803
Long-term marketable securities	Between one and three years	151		129
Total cash, cash equivalents and marketable securities		$	950	$	1,138

Realized gains or losses recognized on the sale of available-for-sale marketable securities were not material for the three and nine months ended September 30, 2023 and 2022. Realized gains and losses are included in Interest and other income, net, in the Condensed Consolidated Statements of Operations. The cost of a security sold is determined using the specific-identification method.

We limit the credit risk associated with our investments by placing them with banks and institutions we believe are highly credit worthy and investing in highly rated investments. We held a total of 159 and 219 positions in securities which were in unrealized loss positions as of September 30, 2023 and December 31, 2022, respectively. We do not intend to sell our securities with unrealized loss positions and have concluded we will not be required to sell the securities before recovery of the amortized cost for the investment at maturity. No credit related losses have been recognized for any of the periods presented.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash within the Condensed Consolidated Balance Sheets to the total shown in the Condensed Consolidated Statements of Cash Flows (in millions):

	September 30,
	2023		2022
Cash and cash equivalents	$	184	$	218
Restricted cash (included in Other noncurrent assets)	3		3
Total cash, cash equivalents and restricted cash	$	187	$	221

Note 10. Condensed consolidated balance sheet components

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in millions):

	September 30, 2023		December 31, 2022
Prepaid expenses and other assets	$	27	$	15
Accrued interest receivable	4		4
Total prepaid expenses and other current assets	$	31	$	19

Other Current Liabilities

Other current liabilities consisted of the following (in millions):

	September 30, 2023		December 31, 2022
Accrued research and development	$	41	$	45
Accrued personnel expenses	22		25
Current portion of lease liabilities	9		3
Income taxes payable	3		—
Other	5		3
Total other current liabilities	$	80	$	76

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Note 11. Leases

The following table summarizes our cash and non-cash information related to our operating leases (in millions):

	Nine Months Ended September 30,
	2023		2022
Cash paid for amounts included in measurement of lease liabilities	$	12	$	8
Cash received from tenant improvement allowances	$	8	$	8
Right-of-use assets obtained in exchange for new operating lease liabilities	$	—	$	3
Recognition of tenant improvement allowance receivable included in Other current liabilities	$	4	$	6

As of September 30, 2023 and December 31, 2022, we have provided deposits for letters of credit totaling $3 million to secure our obligations under our leases, which are included in Other noncurrent assets in the Condensed Consolidated Balance Sheets.

Note 12. Stockholders' Equity

Gilead Stock Purchase

In June 2023, under the Second Stock Purchase Agreement, Gilead purchased 1.0 million shares of our common stock at the closing day purchase price of $19.26 per share for a total cost of $20 million.

At-the-Market Facility

In February 2023, we entered into an equity distribution agreement pursuant to which we may, from time to time, sell shares of our common stock, par value $0.0001 per share, having an aggregate offering price of up to $200 million. In August 2023, we issued and sold 0.2 million shares of our common stock under this agreement for total net proceeds of $5 million.

Note 13. Fair value measurements

We determine the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:

•Level 1 inputs include unadjusted quoted prices in active markets for identical assets or liabilities;

•Level 2 inputs include observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities; quoted prices for identical or similar assets or liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability; and

•Level 3 inputs include unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the underlying asset or liability. Our Level 3 assets and liabilities include those whose fair value measurements are determined using pricing models, discounted cash flow methodologies or similar valuation techniques and significant management judgment or estimation.

Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.

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The following tables summarize the types of assets and liabilities measured at fair value on a recurring basis by level within the fair value hierarchy (in millions):

Fair value measurement as of September 30, 2023	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	110	$	—	$	—	$	110
U.S. treasury securities	—		245		—		245
Corporate securities and commercial paper	—		491		—		491
U.S. government agency obligations	—		96		—		96
Certificate of deposit	—		8		—		8
Total assets measured at fair value	$	110	$	840	$	—	$	950
Liabilities
Liability for sale of future royalties	$	—	$	—	$	19	$	19
Total liabilities measured at fair value	$	—	$	—	$	19	$	19

Fair value measurement as of December 31, 2022	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	169	$	—	$	—	$	169
U.S. treasury securities	—		314		—		314
Corporate securities and commercial paper	—		631		—		631
U.S. government agency securities	—		20		—		20
Certificate of deposit	—		4		—		4
Total assets measured at fair value	$	169	$	969	$	—	$	1,138
Liabilities
Liability for sale of future royalties	$	—	$	—	$	17	$	17
Total liabilities measured at fair value	$	—	$	—	$	17	$	17

Liability for Sale of Future Royalties

In 2021, we entered into an agreement with BVF Partners L.P. (BVF), under which BVF funded the discovery and development of compounds for the treatment of inflammatory diseases (the BVF Program) for $15 million in non-refundable payments which were paid in 2021 and 2022. In return, we are obligated to: perform research and development activities in the Program; make contingent payments upon the achievement of certain clinical and regulatory milestones of up to $73 million or $160 million depending on whether the program is solely developed by us or with Gilead if they opt-in under the Gilead Collaboration Agreement; and pay mid- to high-single digit royalties on any net product sales generated by the BVF Program.

We account for the BVF Agreement as a liability primarily because we have significant continuing involvement in generating the cash flows due to BVF. The liability is recorded at fair value by using probability-adjusted discounted cash flows and is revalued each reporting period until the related contingencies have been resolved. The fair value measurement is based on significant unobservable inputs that are reviewed quarterly by management and include, as applicable, estimated probabilities and the timing of achieving specified development, regulatory and commercial milestones as well as estimated annual sales. Significant changes that increase or decrease the probabilities of achieving the related development, regulatory and commercial events or that shorten or lengthen the time required to achieve such events or that increase or decrease estimated annual sales would result in corresponding increases or decreases in the fair values of the obligations, as applicable. Changes in the fair value of this liability related to interest accretion are recognized in Non-operating income (expense) in the Condensed Consolidated Statements of Operations.

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During the second quarter of 2023, new preclinical information from our BVF Program led to revised assumptions which decreased the estimated probabilities of success and delayed the projected timing of achieving specified development, regulatory and commercial milestones and commercial sales. These changes in estimates are accounted for prospectively and resulted in a decrease in the imputed effective interest rate on the unamortized portion of the liability to 10.1% commencing with the quarter ended June 30, 2023, compared to 20.6% for the quarters ended March 31, 2023 and prior. The impact of this change on the non-cash interest expense for the quarter and nine months ended September 30, 2023 was not material when compared to the prior year periods. The liability for sale of future royalties is reported in Other noncurrent liabilities in the Condensed Consolidated Balance Sheets and changes were as follows (in millions):

	Nine Months Ended September 30,
	2023		2022
Beginning balance	$	17	$	5
Cash received	—		5
Interest accretion	2		2
Ending balance	$	19	$	12

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

You should read the following discussion and analysis of our financial condition and results of operations together with our unaudited Condensed Consolidated Financial Statements and related notes in Part I, Item 1 of this Quarterly Report on Form 10-Q and with our audited Consolidated Financial Statements and related notes thereto for the year ended December 31, 2022, included in our Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (SEC) on February 28, 2023. This discussion and other parts of this report contain forward-looking statements that involve risk and uncertainties, such as statements of our plans, objectives, expectations, and intentions. Further, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this Quarterly Report on Form 10-Q, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. Our actual results could differ materially from those discussed in these forward-looking and other statements. Factors that could cause or contribute to such differences include, but are not limited to, those discussed in the section of this report titled “Risk Factors.”

Overview

We are a clinical-stage biopharmaceutical company focused on creating best-in-class therapies. Using our robust and highly efficient drug discovery capability, we have created a significant portfolio of investigational products which are in clinical development, with our most advanced molecule, an anti-TIGIT antibody, now in four Phase 3 registrational studies targeting lung and gastrointestinal cancers. Our deep portfolio of novel small molecules and enabling antibodies allows us to create highly differentiated therapies, which we are developing to treat multiple large indications. We expect our clinical-stage portfolio to continue to expand and to include molecules targeting immuno-oncology, cancer cell-intrinsic and immunological pathways. Our vision is to create, develop and commercialize highly differentiated therapies that have a meaningful impact on patients.

Our Clinical Product Portfolio

We are currently developing multiple investigational products in clinical studies, including new combination approaches that target TIGIT, PD-1, the adenosine axis (CD73 and dual A2a/A2b receptor) and HIF-2a. We have entered into an Option, License and Collaboration Agreement (as amended, the Gilead Collaboration Agreement) with Gilead Sciences, Inc. (Gilead) to strategically advance our portfolio through a collaborative relationship. The Gilead Collaboration Agreement provides Gilead with an exclusive license to our anti-PD-1 program (including zimberelimab) and time-limited exclusive option rights to our clinical programs, which they have exercised for our anti-TIGIT program (including domvanalimab), adenosine receptor antagonist program (including etrumadenant) and CD73 program (including quemliclustat). For all such optioned programs, we are co-developing investigational products with Gilead.

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The following chart summarizes our clinical pipeline:

dom: domvanalimab; etruma: etrumadenant; gem/nab-pac: gemcitabine/nab-paclitaxel; nivo: nivolumab; pembro: pembrolizumab; quemli: quemliclustat; rego: regorafenib; zim: zimberelimab

*+/- biologic, e.g. bevacizumab or biosimilar, will be included for all patients in whom it is not contraindicated

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Recent Developments

The following is a summary of the recent significant developments affecting our business:

•In November 2023, we presented preliminary data from Arm A1 of the Phase 2 EDGE-Gastric study, evaluating domvanalimab plus zimberelimab and chemotherapy in patients with previously untreated, locally advanced unresectable or metastatic upper gastrointestinal (GI) cancers. These data were from the cohort that includes a similar patient population and dosing regimen as the ongoing Phase 3 study, STAR-221.

◦Domvanalimab plus zimberelimab and chemotherapy showed encouraging objective response rates (ORR) of 80% (confirmed ORR (cORR) of 73%) in patients with PD-L1-high tumors (tumor activity positivity (TAP) ≥5%), 46% (all confirmed) in patients with PD-L1-low (TAP <5%) tumors and 59% (cORR of 56%) for patients overall.

◦Six-month landmark progression-free survival (PFS) was 93% for patients with PD-L1-high tumors (TAP ≥5%), 68% for patients with PD-L1-low tumors (TAP <5%) and 77% for patients overall. Mature PFS has not been reached and data are expected in the second half of 2024.

◦Domvanalimab plus zimberelimab and chemotherapy was well tolerated, with a similar safety profile to what has been reported for anti-PD1 plus chemotherapy in this setting.

•Pharmacokinetic and pharmacodynamic data from the dose-escalation phase of ARC-20, a Phase 1b study in cancer patients of AB521, a potential best-in-class HIF-2a inhibitor, is consistent with results seen in healthy volunteers.

Components of Operating Results

Revenues

We have not generated any revenue from product sales and do not expect to generate any revenue from product sales for the foreseeable future. All revenue recognized to date has been through research, collaboration and license arrangements with strategic partners.

License and Development Services Revenue

Our license and development services revenue consists of amounts recognized from the portions of the nonrefundable upfront and milestone payments received from Gilead and Taiho and allocated to performance obligations for licenses or R&D activities performed by us as we develop our investigational products under the terms of our collaboration agreements. License and development services revenues are recognized based upon the timing of the delivery of a license or service if delivery is complete, or based on estimates of each performance obligation's percentage of completion at the period end if it is still in process. We calculate percentage of completion as a ratio of effort incurred to date on each performance obligation to the total estimated effort to be incurred to satisfy that performance obligation.

Other Collaboration Revenue

Other collaboration revenue consists primarily of amounts recognized from the portions of the nonrefundable upfront payments received from Gilead and Taiho and allocated to performance obligations relating to access to our investigational pipeline recognized over the period of access.

Operating Expenses

Research and Development Expenses

Our research and development expenses consist of expenses incurred in connection with the research and development of our pipeline programs. These expenses include preclinical and clinical expenses, payroll and personnel expenses, including stock-based compensation for our employees, laboratory supplies, product licenses, consulting costs, contract research, and depreciation. Shared facility expenses are allocated to functional groups proportionally based on usage. Under certain collaboration agreements we agree to share research and development expenses with our partners. Such cost sharing arrangements may result in receiving reimbursement from our partners or require that we reimburse our partners for qualified expenses. We expense both internal and external research and development costs as they are incurred. We record advance payments for services that will be used or rendered for future research and development activities as prepaid expenses and recognize them as an expense as the related services are performed. We recognize reimbursement for shared costs incurred by us and reimbursed by our partners as a reduction in research and development expense.

We do not allocate our costs by investigational product, as a significant amount of research and development expenses include internal costs, such as payroll and other personnel expenses, and certain external costs that are not

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recorded at the investigational product level. In particular, with respect to internal costs, several of our departments support multiple research and development programs, and we do not allocate those costs by investigational product.

The level of our future research and development investment will depend on a number of factors and uncertainties, including the breadth of the joint development program agreed to with Gilead for the optioned programs, the outcome of our efforts, and the amount of cost reimbursements or milestone payments we receive from our collaborators. We expect our research and development expenses to increase substantially during the next few years as we pursue joint development programs with Gilead and advance these programs towards regulatory approval. We also expect to advance new programs into the clinic. All of this will require significant growth in our development capabilities and infrastructure. In addition, our joint development programs with Gilead for the optioned molecules are anticipated to include a significant number of later-stage clinical trials, which typically include a larger number of subjects, are of a longer duration and include more geographic regions. As we advance our clinical-stage programs and prepare to seek regulatory approval, we will also need to increase our late-stage manufacturing activities. As a result, we expect our preclinical, clinical, and contract manufacturing expenses to increase significantly relative to what we have incurred to date.

In addition, under our arrangements with WuXi Biologics, Abmuno, AstraZeneca and BVF, we may incur additional clinical and regulatory milestone payments based on the development progress of our investigational products. We may also be required to pay royalties in the event of a successful product launch and our receipt of commercial revenues. Therefore, we are unable to predict the timing or the final cost to complete our clinical programs or validation of our manufacturing and supply processes and delays may occur due to numerous factors. Factors that could cause or contribute to delays or additional costs include, but are not limited to, those discussed in “Item 1A. Risk Factors.”

General and Administrative Expenses

General and administrative expenses consist principally of personnel-related costs including payroll and stock-based compensation for personnel in executive, finance, human resources, information technology, business and corporate development, and other administrative functions. Shared facility expenses are allocated to functional groups proportionally based on usage. Our general and administrative expenses also include professional fees for legal, consulting, and accounting services, rent and other facilities costs, fixed asset depreciation, and other general operating expenses not otherwise classified as research and development expenses. We do not receive significant reimbursements of these costs through our collaboration with Gilead.

We anticipate that our general and administrative expenses will increase during the next few years as we support our growing research and development activities, including due to staff expansion, and other costs associated with increased infrastructure needs.

Non-Operating Income, net

Non-operating income, net consists primarily of interest earned on our investments in fixed-income marketable securities and non-cash interest expense incurred under the effective interest method on our liability for sale of future royalties to BVF.

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Results of Operations

The following table summarizes our results of operations (in millions):

	Three Months Ended September 30,				Change		Nine Months Ended September 30,				Change
	2023		2022				2023		2022
Revenues:
License and development service revenue	$	22	$	23	(4	%)	$	58	$	48	21	%
Other collaboration revenue	10		10		0	%	28		30		(7)	%
Total revenues	32		33		(3	%)	86		78		10	%
Operating expenses:
Research and development	82		77		6	%	247		208		19	%
General and administrative	30		26		15	%	88		76		16	%
Total operating expenses	112		103		9	%	335		284		18	%
Loss from operations	(80)		(70)		14	%	(249)		(206)		21	%
Non-operating income, net	11		5		120	%	28		7		*
Loss before income taxes	(69)		(65)		6	%	(221)		(199)		11	%
Income tax expense	(2)		—		*		(5)		(1)		*
Net loss	$	(71)	$	(65)	9	%	$	(226)	$	(200)	13	%

*Not meaningful

Total Revenues

The decrease in Total revenues for the three months ended September 30, 2023 was primarily driven by decreased revenues from license and development services due to the progress in research and development activities for our programs, primarily zimberelimab, partially offset by an increase in revenue related to our Taiho collaboration.

The increase in Total revenues for the nine months ended September 30, 2023 was primarily driven by increased revenues from license and development services due to the progress in the research and development activities for our programs, primarily etrumadenant, partially offset by a decrease in revenue recognized for zimberelimab.

See Note 5, Revenues to our Condensed Consolidated Financial Statements in Part I, Item 1 for further discussion of the amount and timing of revenues recognized from our license and collaboration agreements.

Research and Development Expenses

The increase of 6% or $5 million in Research and development expenses for the three months ended September 30, 2023 was primarily driven by: $7 million of higher spend for Arcus programs not under a cost-sharing collaboration due to our expanding clinical and development activities; partially offset by a net decrease of $2 million in shared costs for programs optioned by our collaboration partners, primarily from the Gilead collaboration. The net decrease of $2 million was due to a decrease in shared collaboration costs of $10 million primarily from the timing of clinical manufacturing; with a corresponding decrease in reimbursements for shared expenses of $8 million. Non-cash stock-based compensation expense was $8 million for each of the third quarter 2023 and 2022. The net increase was primarily driven by: $3 million in net clinical costs due to our expanding clinical and development activities as we enrolled more patients in our existing and new studies; and $3 million increase in net employee compensation costs due to our growing headcount.

The increase of 19% or $39 million in Research and development expenses for the nine months ended September 30, 2023 was primarily driven by: $47 million in higher costs incurred to support our expanded clinical and development activities including $19 million in higher costs due to the timing of standard-of-care therapeutic purchases and $17 million in lower costs due to the timing of clinical manufacturing; partially offset by $8 million in higher reimbursements for shared expenses from our collaborations, primarily the Gilead collaboration. The net increase was primarily driven by $21 million in net clinical costs due to our expanding clinical and development activities as we enrolled more patients in our existing and new studies and $19 million increase in net employee compensation costs due to our growing headcount, including $2 million in increased non-cash stock-based compensation.

For the three months ended September 30, 2023 and 2022, we recognized reimbursements for shared expenses from our collaborations of $33 million and $41 million, respectively. For the nine months ended September 30, 2023 and

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2022, we recognized reimbursements for shared expenses from our collaborations of $119 million and $111 million, respectively. Reimbursements are driven primarily by the Gilead collaboration.

R&D expense by quarter may fluctuate due to the timing of clinical manufacturing and standard-of-care therapeutic purchases with a corresponding impact on reimbursements.

General and Administrative Expenses

The increase of 15% or $4 million in General and administrative expenses for the three months ended September 30, 2023 was primarily driven by the increased complexity of supporting our expanding clinical pipeline and partnership obligations. Our growing headcount and our 2023 stock awards drove a $2 million increase in employee compensation costs, primarily due to increased non-cash stock-based compensation.

The increase of 16% or $12 million in General and administrative expenses for the nine months ended September 30, 2023 was primarily driven by the increased complexity of supporting our expanding clinical pipeline and partnership obligations. Our growing headcount and our 2023 stock awards drove a $9 million increase in employee compensation costs, including $5 million in increased non-cash stock-based compensation.

Non-Operating Income, net

The increase of $6 million and $21 million in Non-operating income, net for the three and nine months ended September 30, 2023, respectively, was primarily due to higher interest income resulting from increased investment yields as compared to the prior year.

Income Tax Expense

The increase of $2 million and $4 million in Income tax expense for the three and nine months ended September 30, 2023, respectively was primarily due to an increase in taxable income compared to the prior year.

Liquidity and Capital Resources

Sources of Liquidity

To date, we have financed our operations primarily from the sale of our equity securities and payments received under our research, collaboration and license agreements with our strategic partners including Gilead. We expect to incur substantial expenditures in the foreseeable future for the development and potential commercialization of our investigational products and ongoing internal research and development programs. At this time, we cannot reasonably estimate the nature, timing or aggregate amount of costs for our development, potential commercialization, and internal research and development programs.

As of September 30, 2023, we had $950 million of cash, cash equivalents, and marketable securities, compared to $1.1 billion as of December 31, 2022. The decrease in cash from the prior year end is primarily due to the use of cash in our research and development activities. Our cash and investments are held in a variety of interest-bearing instruments, including money market funds, U.S. government treasury obligations, investments in corporate securities and certificates of deposit.

Based on our existing business plan, we believe that our existing cash, cash equivalents, and marketable securities will be sufficient to fund our planned level of operations into 2026.

Our cash flow and financing requirements are determined by analyses of operating and capital spending budgets. It is challenging to predict the nature, timing and estimated long-range costs of the efforts that will be necessary to complete the development of, and obtain regulatory approval for, any of our investigational products. This is made more challenging by events outside of our control. Accordingly, our operating plan may change, including as a result of factors currently unknown to us, and we may need to seek additional funds sooner than planned. Such financing may result in dilution to stockholders, imposition of debt covenants and repayment obligations, or other restrictions that may adversely affect our business. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans.

See “Part II, Item 1A. Risk Factors” for additional risks associated with our substantial capital requirements.

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Cash Flows

The following table summarizes our cash flow activities for each of the periods presented below (in millions):

	Nine Months Ended September 30,
Net cash provided by (used in):	2023		2022
Operating activities	$	(218)	$	508
Investing activities	$	166	$	(460)
Financing activities	$	30	$	22

Operating Activities

Net cash used in operating activities was $218 million for the nine months ended September 30, 2023 as compared to net cash provided by operating activities of $508 million for the same period in the prior year. The change in operating cash flows is primarily due to $725 million received from Gilead in January 2022 under the Gilead Collaboration Agreement.

Investing Activities

Cash provided by investing activities for the nine months ended September 30, 2023 was primarily due to net proceeds from marketable securities of $184 million.

Cash used in investing activities for the nine months ended September 30, 2022 was primarily due to net purchases of short-term and long-term securities as we invested a portion of the $725 million received from Gilead in January 2022 under the Gilead Collaboration Agreement.

Financing Activities

Cash provided by financing activities for the nine months ended September 30, 2023 was due to net proceeds of $25 million from issuance of our common stock and proceeds of $5 million for stock issued under our equity award plans.

Cash provided by financing activities for the nine months ended September 30, 2022 was due to net proceeds of $17 million for stock issued under our equity award plans and $5 million received under the BVF agreement.

Critical Accounting Judgments and Estimates

Our Condensed Consolidated Financial Statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP). The preparation of these Condensed Consolidated Financial Statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Condensed Consolidated Financial Statements, as well as the reported revenue and expenses incurred during the reporting periods. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

There have been no material changes to our critical accounting policies and estimates, from those disclosed in our Annual Report on Form 10-K for the year ended December 31, 2022.

Contractual Obligations and Commitments

There have been no material changes to our contractual obligations outside the ordinary course of business during the nine months ended September 30, 2023, as compared to those disclosed in our Annual Report on Form 10-K for the year ended December 31, 2022.

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Item 3. Quantitative and Qualitative Disclosures About Market Risk.

The market risk inherent in our financial instruments and in our financial position represents the potential loss arising from changes in interest rates and foreign currency exchange rates. Our market risks have not changed materially from those discussed in our Annual Report on Form 10-K filed with the SEC on February 28, 2023.

Item 4. Controls and Procedures.

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our Securities Exchange Act of 1934 (Exchange Act) reports is recorded, processed, summarized, and reported within the time periods specified in the rules and forms of the Securities and Exchange Commission, and that such information is accumulated and communicated to management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure.

A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Because of inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues, if any, within an organization have been detected. Accordingly, our disclosure controls and procedures are designed to provide reasonable, not absolute, assurance that the objectives of our disclosure control system are met.

As of the end of the period covered by this report, we carried out an evaluation, under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, of the effectiveness of our disclosure controls and procedures pursuant to Exchange Act Rule 13a-15. Based upon, and as of the date of this evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective at the reasonable assurance level.

There were no changes in our internal control over financial reporting during the quarter ended September 30, 2023 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. From time to time, we may become involved in legal proceedings arising in the ordinary course of our business. Regardless of outcome, litigation can have an adverse impact on us due to defense and settlement costs, diversion of management resources, negative publicity, reputational harm and other factors.

Item 1A. Risk Factors.

You should consider carefully the following risk factors, together with all the other information in this report, including our Condensed Consolidated Financial Statements and notes thereto, and in our other public filings with the SEC, including our Annual Report on Form 10-K filed with the SEC on February 28, 2023. The occurrence of any of the following risks could harm our business, financial condition, results of operations and/or growth prospects or cause our actual results to differ materially from those contained in forward-looking statements we have made in this report and those we may make from time to time. You should consider all of the risk factors described when evaluating our business.

Risks Related to our Limited Operating History, Financial Position and Capital Requirements

We have a history of operating losses, have never generated any revenue from product sales and anticipate that we will continue to incur significant losses for the foreseeable future.

We are a pre-commercial immuno-oncology company with a limited operating history that may make it difficult to evaluate the success of our business to date and to assess our future viability. All of our investigational products are in development, and none have been approved for commercial sale nor have we ever generated any revenue from product sales. Our revenues to date have been primarily from upfront and milestone payments, research and development support and clinical materials reimbursement from our strategic partners. For the nine months ended September 30, 2023 and the year ended December 31, 2022 we had net losses of $226 million and $267 million, respectively. As of September 30, 2023, we had an accumulated deficit of $768 million. We expect that it will be several years, if ever, before we have an investigational product ready for commercialization. While we may receive income from year to year under the Gilead Agreement and Taiho Agreement, we generally expect to incur substantial and increasing levels of operating losses over the next several years and for the foreseeable future as we advance our investigational products. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on our stockholders’ equity and working capital.

To become and remain profitable on a sustained basis, we must develop and eventually commercialize a product with significant market potential. This will require us to be successful in a range of challenging activities, including completing preclinical studies and clinical trials of our investigational products, obtaining marketing approval for these investigational products, manufacturing, marketing and selling those products for which we may obtain marketing approval and satisfying any post-marketing requirements. We may never succeed in these activities and, even if we succeed in commercializing one or more of our investigational products, we may never generate revenues that are significant or large enough to achieve sustained profitability. In addition, we may encounter unforeseen expenses, difficulties, complications, delays and other known and unknown challenges. If we do achieve profitability from product sales, we may not be able to sustain or increase profitability on a quarterly or annual basis and we will continue to incur substantial research and development and other expenditures to develop and market additional investigational products. Our failure to become and remain profitable on a sustained basis would decrease the value of the 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 could also cause our stockholders to lose all or part of their investment.

We may need to obtain additional funding to finance our operations and complete the development and any commercialization of our investigational products. If we do not receive substantial opt-in, milestone or royalty payments from our existing collaboration agreements, or are unable to raise additional capital when needed, we may be forced to restrict our operations or delay, reduce or eliminate our product development programs.

The development of biopharmaceutical investigational products is capital intensive. Since our inception, we have used substantial amounts of cash to fund our operations and expect our expenses to increase substantially during the next few years as our investigational products enter and advance into and through large late-stage or registrational clinical trials and we expand our clinical, regulatory, quality and manufacturing capabilities. In addition, if we obtain marketing approval for any of our investigational products, we expect to incur significant commercialization expenses related to marketing, sales, manufacturing and distribution.

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As of September 30, 2023, we had $950 million of cash, cash equivalents and marketable securities. While we believe that our cash position will be sufficient to fund our anticipated level of operations into 2026, our future capital requirements will depend on many factors, including:

•the number, scope, rate of progress and costs of clinical programs and investigational products as well as drug discovery, preclinical development activities, and laboratory testing;

•the scope and costs of manufacturing development and commercial manufacturing activities;

•the scope and costs of developing and supporting new non-oncology programs;

•the scope of any cost sharing arrangements with our strategic partners;

•the timing and amount of milestone payments and option fees we receive under the Gilead Collaboration Agreement and Taiho Agreement;

•the extent to which we acquire or in-license other investigational products and technologies;

•the cost, timing and outcome of regulatory review of our investigational products;

•the cost and timing of establishing sales and marketing capabilities, if any of our investigational products receive marketing approval;

•the costs of preparing, filing and prosecuting patent applications, maintaining and enforcing our intellectual property rights and defending intellectual property-related claims;

•the costs associated with being a public company; and

•the cost associated with commercializing our investigational products, if they receive marketing approval.

We cannot guarantee that future financing will be available in sufficient amounts or on terms acceptable to us, if at all. Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our ability to develop and commercialize our investigational products. If we are unable to raise capital when needed or on attractive terms, we would be forced to delay, reduce or eliminate our research and development programs or future commercialization efforts. In addition, if we are able to raise additional capital, raising additional capital may cause dilution to our stockholders, restrict our operations or require us to relinquish rights to our technologies or investigational products.

Risks Related to the Discovery and Development of our Investigational Products

If we are unable to obtain regulatory approval for our investigational products, or experience significant delays in doing so, our business will be materially harmed.

We have no products approved for sale and our investigational products must be approved by the Food and Drug Administration (FDA) in the United States and similar regulatory authorities outside the United States, such as the EMA, prior to commercialization. The process of obtaining marketing approvals, both in the United States and abroad, is expensive and takes many years, if approval is obtained at all, and can vary substantially based upon a variety of factors. Securing marketing approval requires the submission of extensive preclinical and clinical data and supporting information to regulatory authorities for each therapeutic indication to establish the investigational product’s safety and efficacy. Securing marketing approval also requires the submission of information about the product manufacturing process to, and inspection of manufacturing facilities by, the regulatory authorities, among other requirements. Our investigational products may not be effective, may be only moderately effective, may not have an acceptable durability of response, may not have an acceptable risk-benefit profile or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude us from obtaining marketing approval or limit their commercial use. Our investigational products may not be approved even if they achieve their primary endpoints in any Phase 3 clinical trials or registrational trials we or our collaborators conduct.

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The FDA and comparable foreign regulatory authorities have substantial discretion in the approval process and in determining when or whether marketing approval will be obtained for any of our investigational products. Regulatory authorities may refuse to accept any application or may decide that our data are insufficient for approval and require additional preclinical, clinical or other studies. In addition, varying interpretations of the data obtained from preclinical and clinical testing could delay, limit or prevent marketing approval of an investigational product. 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 product application, may also cause delays in or prevent the approval of an application. For example, since a key element of our strategy is the development of intra-portfolio combinations, regulatory authorities may disagree that we have sufficiently demonstrated the contribution of each investigational product or other agent in our combination trials and require further studies.

Even if we are able to obtain marketing approvals for any of our investigational products, those approvals may be for indications that are not as broad as desired or may contain other limitations that would adversely affect our ability to generate revenue from sales of those products. Moreover, if we are not able to differentiate our product against other approved products within the same class of drugs, or if any of the other circumstances described above occur, our business would be materially harmed and our ability to generate revenue from that class of drugs would be severely impaired.

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

Clinical drug development is a lengthy, expensive and uncertain process.

The research and development of drugs and biological products is an extremely risky industry. Only a small percentage of investigational products that enter the development process ever receive marketing approval. Before obtaining marketing approval from regulatory authorities for the sale of any investigational product, we must complete preclinical development and then conduct extensive clinical trials to demonstrate the safety and efficacy of our investigational products in humans. Clinical testing is expensive, can take many years to complete and its outcome is uncertain.

The results of preclinical studies and early clinical trials are not always predictive of future results.

The results of preclinical and early clinical trials of our investigational products and other products with the same mechanism of action may not be predictive of the results of later-stage clinical trials. Clinical trial failure may result from a multitude of factors including flaws in study design, dose selection, placebo effect, patient enrollment criteria and failure to demonstrate favorable safety or efficacy traits. As such, failure in clinical trials can occur at any stage of testing. A number of companies in the biopharmaceutical industry have suffered setbacks in the advancement of clinical trials due to lack of efficacy or adverse safety profiles, notwithstanding promising results in earlier trials. Based upon negative or inconclusive results, we may decide, or regulators may require us, to conduct additional clinical trials or preclinical studies. In addition, data obtained from clinical trials are susceptible to varying interpretations, and regulators may not interpret our data as favorably as we do, which may further delay, limit or prevent marketing approval. In particular, results from uncontrolled trials, meaning trials in which there is no control group such as a placebo group, are inherently difficult to interpret. This difficulty is compounded in clinical trials such as ours, in which two or more investigational products that have not yet been approved are being evaluated. Accordingly, the preliminary data from clinical trials of certain of our investigational products may not be predictive of future clinical trial results for these or other investigational products when studied in a randomized environment or larger patient populations.

Most of our clinical trials are open-label studies and may be susceptible to bias.

Most of our clinical trials, including our Phase 3 trials, are open-label studies in which both the patient and investigator know whether the patient is receiving the investigational products or either an existing approved drug or placebo. Open-label clinical trials are susceptible to bias that may exaggerate any therapeutic effect or overestimate the risk associated with the investigational product. Patients may perceive their symptoms to have improved merely due to their awareness of receiving an experimental treatment. Investigators may interpret the information of the treated group more favorably given their awareness of the treatment regimen or may attribute safety risks to the investigational product.

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Enrollment and retention of subjects in clinical trials is expensive and time consuming, can be made more difficult or rendered impossible by competing treatments, clinical trials of competing investigational products, geopolitical instability and public health epidemics, each of which could result in significant delays and additional costs in our product development activities, or in the failure of such activities.

We may encounter delays in enrolling, or be unable to enroll and maintain, a sufficient number of subjects to complete any of our clinical trials. Patient enrollment and retention in clinical trials is a significant factor in the timing and cost of clinical trials and depends on many factors, including the size of the patient population required for analysis of the trial’s primary endpoints, the nature of the trial protocol, our ability to recruit clinical trial investigators with the appropriate competencies and experience, the existing body of safety and efficacy data with respect to the investigational product, the number and nature of competing products or investigational products and ongoing clinical trials of competing investigational products for the same indication, the proximity of subjects to clinical trial sites, the eligibility criteria for the clinical trial and our ability to obtain and maintain subject consents.

For example, enrollment of oncology subjects in our clinical trials evaluating zimberelimab may be hampered by nivolumab from Bristol-Myers Squibb and pembrolizumab from Merck, both of which are approved and on the market. Subjects may opt to be treated with an approved product rather than our anti-PD-1 antibody investigational product. In addition, Roche/Genentech, Merck and Beigene have initiated numerous Phase 3 trials with their respective anti-TIGIT antibodies, which could reduce the number of clinical sites and subjects available for our registrational program for domvanalimab (our anti-TIGIT antibody), including ARC-10 and STAR-121, each Phase 3 trials in lung cancer, and STAR-221, our Phase 3 trial in upper gastrointestinal tract cancer.

Geopolitical instability and public health outbreaks may have an adverse impact our clinical trial operations. For example, we suspended clinical trial activities, including the enrollment of subjects, following the outbreak of war in Israel. If there are other geopolitical conflicts, a resurgence of the COVID-19 pandemic or additional public health outbreaks, we may further suspend or redirect our clinical trial activities, regulatory authorities and ethics committees may choose to divert resources and the time for review of new studies and any protocol or other amendments for ongoing studies may be prolonged. Our investigational sites may intermittently divert resources in order to respond to an ongoing health or humanitarian crisis, which could cause delays and limit their ability to initiate new studies. The limited resources at investigational sites in these situations would further hinder their ability to screen and enroll subjects, conduct and report all patient assessments and collect all patients' samples, thereby impacting our ability to assess the activity of our investigational products in a timely manner.

In addition, recruiting and retaining subjects in our clinical trials may be adversely impacted by negative results that we report in our other clinical trials using the same investigational products or by negative results reported by others using investigational products with the same mechanism of action as our investigational products. Delays in patient enrollment may result in increased costs or may affect the timing or outcome of the planned clinical trials, which could prevent completion of these trials and adversely affect our ability to advance the development of our investigational products. Failures in planned subject enrollment or retention may result in increased costs or program delays and could render further development impossible.

If we do not achieve our product development goals in the time frames we announce and expect, the commercialization of our investigational products may be delayed, our share price may decline and our commercial prospects may be adversely affected.

Drug development is inherently risky and uncertain. The actual timing of our development milestones can vary significantly compared to our estimates, in some cases for reasons beyond our control, for any number of reasons, including:

•delays in completing IND-enabling preclinical studies or developing manufacturing processes and associated analytical methods that meet good manufacturing practice (cGMP) requirements;

•the FDA placing a clinical trial on hold;

•the FDA requesting additional information, which could necessitate generating additional information at significant cost in terms of both time and expenses;

•our prioritization of other of our investigational products for advancement or the emergence of competing investigational products developed by others;

•challenges and delays in trial execution associated with our testing of multiple investigational products in the same indication in different clinical trials;

•subjects failing to enroll or remain in our trial at the rate we expect;

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•subjects choosing an alternative treatment or other investigational products, or participating in competing clinical trials;

•lack of adequate funding to continue our clinical trials;

•subjects experiencing severe or unexpected drug-related adverse effects;

•any interruptions or delays in the supply of our investigational products for our clinical trials;

•a facility manufacturing any of our investigational products or any of their components being ordered by the FDA or comparable foreign regulatory authorities to temporarily or permanently shut down due to violations of cGMP regulations or other applicable requirements, or infections or cross-contaminations of investigational products in the manufacturing process;

•any changes to our manufacturing process or product specifications that may be necessary or desired;

•any failure or delay in reaching an agreement with contract research organizations (CROs) and clinical trial sites;

•third-party clinical investigators losing the licenses or permits necessary to perform our clinical trials, not performing our clinical trials on our anticipated schedule or consistent with the clinical trial protocol, good clinical practices (GCP) or regulatory requirements or other third parties not performing data collection or analysis in a timely or accurate manner;

•third-party contractors becoming debarred or suspended or otherwise penalized by the FDA or other comparable foreign regulatory authorities for violations of applicable regulatory requirements, in which case we may need to find a substitute contractor, and we may not be able to use some or all of the data produced by such contractors in support of our marketing applications;

•one or more Institutional Review Boards (IRBs) refusing to approve, suspending or terminating the trial at an investigational site, precluding enrollment of additional subjects, or withdrawing its approval of the trial;

•changes in regulatory requirements and policies which may require us to amend clinical trial protocols to comply with these changes and resubmit our clinical trial protocols to IRBs for reexamination;

•delays due to new regulatory requirements which may take time for us and the third-parties we engage to incorporate into our operations to ensure compliance; or

•health crises, such as COVID-19, which may restrict the ability of trial sites to initiate new trials, screen patients for enrollment or treat enrolled patients, and divert clinical trial site resources away from the conduct of our clinical trials.

These and other factors may also lead to the suspension or termination of clinical trials, and ultimately the denial of regulatory approval of an investigational product. Any delays in achieving our development goals may allow our competitors to bring products to market before we do and adversely affect our commercial prospects and cause our stock price to decline.

Preliminary and interim data from our clinical studies that we announce or publish from time to time are subject to audit and verification procedures that could result in material changes in the final data and may change as more patient data become available.

From time to time, we publish preliminary or interim data from our clinical studies. Preliminary data remain subject to audit confirmation and verification procedures that may result in the final data being materially different from the preliminary data we previously published. Interim data are also 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. As a result, topline results that we report may differ from future results of the same studies and interim data should be viewed with caution until the final data are available. Material adverse changes in the final data could significantly harm our business prospects.

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Serious adverse events, undesirable side effects or other unexpected properties of our investigational products may be identified during development or after approval, which could lead to the discontinuation of our clinical development programs, refusal by regulatory authorities to approve our investigational products or limitations on the use of our investigational products or, if discovered following marketing approval, revocation of marketing authorizations or subsequent limitations on the use of our investigational products.

As we continue to develop our investigational products and initiate clinical trials of additional investigational products, serious adverse events, undesirable side effects or unexpected characteristics may emerge causing us to abandon these investigational products or limit their development to more narrow uses or subpopulations in which the serious adverse events, undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective. Even if our investigational products initially show promise in early clinical trials, the side effects of drugs are frequently only detectable after they are tested in large, Phase 3 clinical trials or, in some cases, after they are made available to patients on a commercial scale after approval. Sometimes, it can be difficult to determine if the serious adverse or unexpected side effects were caused by the investigational product or another factor, especially in oncology subjects who may suffer from other medical conditions and be taking other medications. If serious adverse or unexpected side effects are identified during development and are determined to be attributed to our investigational product, we may be required to develop a Risk Evaluation and Mitigation Strategy (REMS) to mitigate those serious safety risks, which could impose significant distribution and use restrictions on our products.

Drug-related side effects could also affect subject recruitment or the ability of enrolled subjects to complete the trial or result in potential product liability claims. Any of these occurrences may harm our business prospects significantly.

In addition, if one or more of our investigational products receives marketing approval, and we or others later identify undesirable side effects caused by such products, a number of potentially significant negative consequences could result, including:

•regulatory authorities may withdraw approvals of such product;

•regulatory authorities may require additional warnings on the label;

•we may be required to create a medication guide outlining the risks of such side effects for distribution to patients;

•regulatory authorities may impose subsequent limitations on the use of the product;

•we could be sued and held liable for harm caused to patients; and

•our reputation may suffer.

Any of these events could prevent us from achieving or maintaining market acceptance of the particular investigational product, if approved, and could significantly harm our business, results of operations and prospects.

Adverse findings from clinical trials conducted by third parties investigating the same investigational products as us in different territories or different investigational products directed to the same target as one of our programs could adversely affect our development program.

Lack of efficacy, adverse events, undesirable side effects or other adverse findings may emerge in clinical trials conducted by third parties investigating the same investigational products as us in different territories or different investigational products directed to the same target as one of our programs. For example, we and Gloria Biosciences, each licensed our rights to the same anti-PD-1 antibody (which we refer to as zimberelimab) from WuXi Biologics (Cayman) Inc. (WuXi Biologics). Gloria Biosciences refers to this antibody as GLS-010 and is conducting clinical trials with GLS-010 in China. We have no control over their clinical trials or development program, and adverse findings from the results or their conduct of clinical trials could adversely affect our development of zimberelimab or even the viability of zimberelimab as an investigational product. We may be required to report Gloria Biosciences' adverse events or unexpected side effects to the FDA or comparable foreign regulatory authorities, which could, among other things, order us to cease further development of zimberelimab. We may face similar risks from any independent development conducted with our investigational products by Gilead and Taiho, following any exercise of their respective options to our programs.

Further, we have no control over the clinical trials or development program of third parties developing investigational products directed to the same target as one of our programs. Adverse findings or results from any of their clinical trials could adversely affect the commercial prospects of our investigational products and cause our stock price to fluctuate or decline.

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A key element of our strategy is the development of intra-portfolio combinations. If we are not successful in discovering, developing and commercializing investigational products that take advantage of different mechanisms of action to achieve superior outcomes relative to the use of single agents or other combination therapies, our ability to achieve our strategic objectives would be impaired.

A key element of our strategy is to build a broad portfolio of investigational products that will allow for the development of intra-portfolio combinations. We believe that by developing or licensing these investigational products, we can control the combinations we pursue and, if and when approved, maximize the commercial potential of these combinations. However, these combinations have not been tested before and may fail to demonstrate synergistic activity against immunological targets, may fail to achieve superior outcomes relative to the use of single agents or other combination therapies, may exacerbate adverse events associated with one of the investigational products when used as monotherapy, or may fail to demonstrate sufficient safety or efficacy traits in clinical trials to enable us to complete those clinical trials or obtain marketing approval for the combination therapy. In addition, our early clinical trials may test more than one investigational product in uncontrolled studies, and it may be difficult to interpret the results of those uncontrolled trials or evaluate the contribution of each investigational agent in such combination.

Even if we are successful in developing combination therapies, competition from other investigational products in the same class which are either already approved or further along in development than ours may prevent us from realizing the commercial potential of our combination therapies and prevent us from achieving our strategic objectives.

Development of combination therapies may present more or different challenges than development of single agent therapies.

Many of our investigational products are being pursued in combination with one or more additional products or investigational products. The development of combination therapies may be more complex than the development of single agent therapies and generally requires that sponsors demonstrate the contribution of each investigational product to the claimed effect and the safety and efficacy of the combination as a whole. This requirement may make the design and conduct of clinical trials more complex, requiring more clinical trial subjects. We also may not be able to meet the FDA’s current or future approval standards required for combination therapies or combination products, if we decided to administer or package a combination therapy as a single drug product. For example, under the "combination rule", the FDA may not file or approve a fixed-dose combination product unless each component of a proposed drug product is shown to make a contribution to the claimed effects and the dosage of each component (amount, frequency, duration) is safe and effective for the intended population. To satisfy these requirements, the FDA typically requires a clinical factorial study, designed to assess the effects attributable to each drug in the combination product. This is particularly true when the ingredients are directed at the same sign or symptom of the disease or condition. The FDA has accepted a variety of approaches to satisfy the combination rule but the FDA has stated that factorial studies may be unethical (e.g., omitting a drug known to improve survival) or impractical (there may be too many components to conduct a factorial study, meaning the trial cannot be conducted). The FDA has also stated that it may be possible to use other types of clinical and nonclinical data and mechanistic information available to demonstrate the contributions of the individual active ingredients to the effect of the combination. Moreover, the applicable requirements for approval of a combination therapy may differ from country to country.

In the event that one of our investigational products were to fail to demonstrate sufficient safety and efficacy or establish its contribution to the claimed effects of a combination therapies, we would need to identify alternatives. For example, we expect that our anti-PD-1 antibody, zimberelimab, will form the backbone of many of the combination therapies we are pursuing. If we are unable to demonstrate the contribution of zimberelimab to the claimed effects of a combination therapy, we would need to identify an anti-PD-1 antibody for use in such combination therapy. In the event we are unable to do so or are unable to do so on commercially reasonable terms, our business and prospects would be materially harmed.

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Certain of our investigational products may require companion diagnostics in certain indications. Failure to successfully develop, validate and obtain regulatory clearance or approval for such tests could harm our product development strategy or prevent us from realizing the full commercial potential of our investigational products.

Companion diagnostics are subject to regulation by the FDA and comparable foreign regulatory authorities as a medical device and may require separate regulatory authorization prior to commercialization. Certain clinical trials that we are conducting, such as our Phase 2 ARC-7 trial and our Phase 3 ARC-10 trial, which are each being conducted in patients with PD-L1≥50% NSCLC, include the use of a diagnostic test to help identify eligible patients. Our future trials may also use a diagnostic test to help identify eligible patients. In addition, we have significant efforts directed to identifying changes in various cells and proteins to understand their relationship, if any, to the clinical activity observed in our clinical trials and to assess if such cells and/or proteins could be used as predictive biomarkers to select for patients more likely to respond to our investigational products. However, we cannot be certain that we will be able to identify any such biomarkers, that such biomarkers will result in us identifying the appropriate patients for our investigational products or that we or any third-party collaborators will be able to validate any diagnostic tests incorporating any predictive biomarkers we may identify.

We currently do not have any plans to develop diagnostic tests internally. We are therefore dependent on the sustained cooperation and effort of third-party collaborators in developing and, if our investigational products are approved for use only with an approved companion diagnostic test, obtaining approval and commercializing these tests. If these parties are unable to successfully develop companion diagnostics for these investigational products, or experience delays in doing so, the development of our investigational products may be adversely affected and we may not be able to obtain marketing authorization for these investigational products. Furthermore, our ability to market and sell, as well as the commercial success, of any of our investigational products that require a companion diagnostic will be tied to, and dependent upon, the receipt of required regulatory authorization and the continued ability of such third parties to make the companion diagnostic commercially available on reasonable terms in the relevant geographies. Any failure to develop, validate, obtain and maintain marketing authorization and supply for a companion diagnostic we need will harm our business prospects.

The design or our execution of our ongoing and future clinical trials may not support marketing approval.

The design or execution of a clinical trial can determine whether its results will support marketing approval, and flaws in the design or execution of a clinical trial may not become apparent until the clinical trial is well advanced. In some instances, there can be significant variability in safety or efficacy results between different trials with the same investigational product due to numerous factors, including differences in trial protocols, size and type of the patient populations, variable adherence to the dosing regimen or other protocol requirements and the rate of dropout among clinical trial participants. The FDA or comparable foreign regulatory authorities may disagree with our trial designs and our interpretation of data from preclinical studies or clinical trials. Even if we adhere to guidance or advice given by the FDA or comparable foreign regulatory authorities, such adherence does not guarantee that the FDA will agree with our trial designs or data interpretations or prevent the FDA from changing the requirements for the approval of any investigational product.

We have conducted, and continue to conduct, portions of our clinical trials outside the United States, and the FDA may not accept data from trials conducted in foreign locations.

We have conducted, and we expect to continue to conduct, portions of our clinical trials outside the United States. Although the FDA may accept data from clinical trials conducted outside the United States, acceptance of these data is subject to certain conditions imposed by the FDA. For example, the clinical trial must be well designed and conducted and performed by qualified investigators in accordance with ethical principles. The trial population must also adequately represent the U.S. population, and the data must be applicable to the U.S. population and U.S. medical practice in ways that the FDA deems clinically meaningful. In general, the patient population for any clinical trials conducted outside the United States must be representative of the population for which we intend to label the product in the United States. In addition, while these clinical trials are subject to the applicable local laws, FDA acceptance of the data will be dependent upon its determination that the trials also complied with all applicable U.S. laws and regulations. We cannot assure you that the FDA will accept data from trials conducted outside the United States. If the FDA does not accept the data from such clinical trials, we would likely need to conduct additional trials, which would be costly and time-consuming and delay or permanently halt our development of our investigational products.

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Risks Related to Reliance on Third Parties, Manufacturing and Commercialization

We expect to depend on our collaboration with Gilead for the research, development, manufacture and commercialization of our investigational products. If this collaboration is not successful, our business could be adversely affected.

Our strategy for fully developing and commercializing our investigational products is dependent upon maintaining our current arrangements with Gilead and our other strategic partners. Our ability to leverage these arrangements to produce commercial success will depend, among other things, on our collaborators' cooperation and ability to successfully meet their responsibilities with regards to a clinical program. We cannot predict the success of any collaboration that we enter into. Our partnership with Gilead poses a number of risks including, but not limited to, the following:

•conflicts may arise between us and Gilead, such as conflicts regarding the combinations or indications to pursue or concerning the interpretation of clinical data, the commercial potential of any optioned investigational products, the interpretation of financial provisions or the ownership of intellectual property developed during the collaboration. Any such conflicts could slow or prevent the development or commercialization of our investigational products;

•if our joint development program does not result in the successful development and commercialization of products or if Gilead terminates the collaboration 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 investigational products could be delayed and we may need additional resources to develop our investigational products;

•we will be heavily dependent on Gilead for its further development and commercialization of the investigational products from the programs that it opts in to;

•we may not be successful in this collaboration due to various other factors, including our ability to demonstrate proof of concept in one or more clinical studies so that Gilead will exercise its option to these programs;

•we have appointed two individuals designated by Gilead to our board of directors pursuant to the terms of the investor rights agreement, and Gilead owns approximately 19.9% of our outstanding common stock and has the right (but not the obligation) to acquire additional shares from us up to an amount resulting in Gilead owning a total of 35% of our outstanding common stock and, as a result, may be able to exert significant influence over our company;

•Gilead could independently develop, or develop with third parties, products that compete directly or indirectly with our investigational products if Gilead believes that competitive products are more likely to be successfully developed or can be commercialized under terms that are more economically attractive than ours; and

•because Gilead has an option to all of our programs, it will be difficult for us to enter into new collaborations.

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We rely on third parties to conduct our clinical trials and perform some of our research and preclinical studies. If these third parties do not satisfactorily carry out their contractual duties or fail to meet expected deadlines, our development programs may be delayed or subject to increased costs, each of which may have an adverse effect on our business and prospects.

We do not have the ability to conduct all aspects of our preclinical testing or clinical trials ourselves. As a result, we are and expect to remain dependent on third parties to conduct our ongoing clinical trials and any future clinical trials of our investigational products. The timing of the initiation and completion of these trials will therefore be partially controlled by such third parties and may result in delays to our development programs. Specifically, we expect CROs, clinical investigators, and consultants to play a significant role in the conduct of these trials and the subsequent collection and analysis of data. However, we will not be able to control all aspects of their activities. Nevertheless, we are responsible for ensuring that each of our trials is conducted in accordance with the applicable protocol and legal, regulatory and scientific standards, and our reliance on the CROs and other third parties does not relieve us of our regulatory responsibilities. We and our CROs are required to comply with GCP requirements, which are regulations and guidelines controlling how clinical trials should be conducted and are applicable to all of our investigational products in clinical development. The FDA and comparable foreign regulatory authorities enforce these GCP requirements through periodic inspections of trial sponsors, clinical trial investigators and clinical trial sites. If we or any of our CROs or clinical trial sites fail to comply with applicable GCP requirements, the data generated in our clinical trials may be deemed unreliable, and the FDA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications.

There is no guarantee that any such CROs, clinical trial investigators or other third parties on which we rely will devote adequate time and resources to our development activities or perform as contractually required. Many of these third parties have and continue to suffer from personnel constraints resulting from COVID-19 and other economic factors which may impact their ability to perform their contractual obligations. If any of these third parties fail to meet expected deadlines, adhere to our clinical protocols or meet regulatory requirements, otherwise performs in a substandard manner, or terminates its engagement with us, the timelines for our development programs may be extended or delayed or our development activities may be suspended or terminated. If any of our clinical trial sites terminates for any reason, we may experience the loss of follow-up information on subjects enrolled in such clinical trials unless we are able to transfer those subjects to another qualified clinical trial site, which may be difficult or impossible. In addition, clinical trial investigators for our clinical trials may serve as scientific advisors or consultants to us from time to time and may receive cash or equity compensation in connection with such services. If these relationships and any related compensation result in perceived or actual conflicts of interest, or the FDA or comparable foreign regulatory authorities concludes that the financial relationship may have affected the interpretation of the trial, the integrity of the data generated at the applicable clinical trial site may be questioned and the utility of the clinical trial itself may be jeopardized, which could result in the delay or rejection of any marketing application we submit by the FDA or any comparable foreign regulatory authority. Any such delay or rejection could prevent us from commercializing our investigational products.

Furthermore, these third parties may also have relationships with other entities, some of which may be our competitors. If these third parties do not successfully carry out their contractual duties, meet expected deadlines or conduct our clinical trials in accordance with regulatory requirements or our stated protocols, we will not be able to obtain, or may be delayed in obtaining, marketing approvals for our investigational products and will not be able to, or may be delayed in our efforts to, successfully commercialize our products.

Supply by third parties of the investigational products, standard-of-care drugs or comparator agents used in our clinical trials may become limited or interrupted which could delay, prevent or impair our development efforts.

We do not have any manufacturing facilities. We produce in our laboratory relatively small quantities of compounds for evaluation in our research programs. We rely, and expect to continue to rely, on third parties for the manufacture and supply of our investigational products for preclinical and clinical testing, as well as for commercial manufacture if any of our investigational products are approved. If any of these third-parties fail to perform these activities for us, nonclinical or clinical development of our investigational products could be delayed, which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects. Further, we currently have limited manufacturing arrangements for our investigational products and expect that each of our investigational products will only be covered by single source suppliers for the foreseeable future. In particular, we have an exclusive relationship with WuXi Biologics, located in China, for the manufacture of zimberelimab drug substance. Our reliance on limited manufacturing arrangements increases the risk that we will not have and may not be able to obtain sufficient quantities of our investigational products for use in our clinical trials, which could delay, prevent or impair our development efforts.

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Any supply chain challenges may affect our ability to supply clinical sites with our investigational products and any standard-of-care drugs and comparator agents that we use in our clinical trials. These supply chain challenges can include longer lead times for the manufacturers of our investigational products to obtain raw materials, longer timeframes to procure or lack of supply for standard-of-care drugs or comparator agents used in our clinical trials, and transit delays at each point in the manufacturing, supply or distribution chain. For example, carboplatin and 5-flourouracil are used in certain of our clinical trials as the standard-of-care chemotherapy agent. However, certain of the countries where we conduct these clinical trials are experiencing a shortage in the supply of carboplatin. These supply chain challenges may delay, prevent or impair our development efforts, or result in increased costs for our clinical trials.

Our manufacturing partners are subject to extensive regulation. In the event any of our manufacturers fail to comply with such regulations or perform its obligations, our business may be adversely affected could negatively and we may need to delay or halt the development of our investigational products.

All entities involved in the preparation of therapeutics for clinical trials or commercial sale, including our existing contract manufacturers for our investigational products, are subject to extensive regulation. Components of a finished therapeutic product approved for commercial sale or used in clinical trials must be manufactured in accordance with cGMP requirements. These regulations govern manufacturing processes and procedures, including record keeping, and the implementation and operation of quality systems to control and assure the quality of investigational products and products approved for sale. Poor control of production processes can lead to the introduction of contaminants, or to inadvertent changes in the properties or stability of our investigational products that may not be detectable in final product testing. We or our contract manufacturers must supply all necessary documentation in support of an NDA or Biologics License Application (BLA) on a timely basis and must adhere to the FDA’s Good Laboratory Practice regulations and cGMP regulations enforced by the FDA through its facilities inspection program. Comparable foreign regulatory authorities may require compliance with similar requirements. The facilities and quality systems of our third-party contractor manufacturers must pass a pre-approval inspection for compliance with the applicable regulations as a condition of marketing approval of our investigational products. We do not control the manufacturing process of, and are completely dependent on, our contract manufacturing partners for compliance with cGMP regulations.

In the event that any of our manufacturers fails to comply with such requirements or to perform its obligations to us in relation to quality, timing or otherwise, we may be forced to manufacture the materials ourselves, for which we currently do not have the capabilities or resources, or enter into an agreement with another third party, which we may not be able to do on commercially reasonable terms, if at all. In particular, any replacement of our manufacturers could require significant effort and expertise because there may be a limited number of qualified replacements. In some cases, the technical skills or technology required to manufacture our investigational products may be unique or proprietary to the original manufacturer and we may have difficulty transferring such skills or technology to another third party and a feasible alternative may not exist. These factors would increase our reliance on such manufacturer or require us to obtain a license from such manufacturer in order to have another third party manufacture our investigational products. If we are required to change manufacturers for any reason, we will be required to verify that the new manufacturer maintains facilities and procedures that comply with quality standards and with all applicable regulations and guidelines. The delays associated with the verification of a new manufacturer could negatively affect our ability to develop investigational products in a timely manner or within budget. Our or a third party’s failure to execute on our manufacturing requirements, to do so on commercially reasonable terms and comply with cGMP could adversely affect our business in a number of ways, including:

•an inability to initiate or continue clinical trials of our investigational products under development;

•delay in submitting regulatory applications, or receiving marketing approvals, for our investigational products;

•loss of the cooperation of an existing or future collaborator, including option exercises by Gilead or Taiho under the Gilead Collaboration Agreement or Taiho Agreement, respectively;

•subjecting third-party manufacturing facilities or our manufacturing facilities to additional inspections by regulatory authorities;

•requirements to cease development or to recall batches of our investigational products; and

•in the event of approval to market and commercialize our investigational products, an inability to meet commercial demands for our product or any other future investigational products.

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Changes in methods of investigational product manufacturing or formulation may result in additional costs or delay.

As investigational products progress through preclinical to late-stage clinical trials to marketing approval and commercialization, it is common that various aspects of the development program, such as the investigational product’s specifications, manufacturing methods and formulation, are altered along the way in an effort to optimize yield and manufacturing batch size, minimize costs and achieve consistent quality and results. Such changes carry the risk that they will not achieve these intended objectives. Any of these changes could cause our investigational products to perform differently and affect the results of planned clinical trials or other future clinical trials conducted with the altered materials. This could delay completion of clinical trials, require the conduct of bridging clinical trials or the repetition of one or more clinical trials, increase clinical trial costs, delay approval of our investigational products and jeopardize our ability to commercialize our investigational products and generate revenue.

Our employees, clinical trial investigators, CROs, consultants, vendors, collaboration partners and any potential commercial partners may engage in misconduct or other improper activities, including non-compliance with regulatory standards and requirements and insider trading.

We are exposed to the risk of fraud or other misconduct by our employees, clinical trial investigators, CROs, consultants, vendors, collaboration partners and any potential commercial partners. Misconduct by these parties could include intentional, reckless and/or negligent conduct or disclosure of unauthorized activities to us that violates: (i) FDA laws and regulations or those of comparable foreign regulatory authorities, including those laws that require the reporting of true, complete and accurate information, (ii) manufacturing standards, (iii) federal and state health and data privacy, security, fraud and abuse, government price reporting, transparency reporting requirements, and other healthcare laws and regulations in the United States and abroad, or (iv) laws that require the true, complete and accurate reporting of financial information or data. Such misconduct could also involve the improper use of information obtained in the course of clinical trials, which could result in regulatory sanctions and cause serious harm to our reputation. We have adopted a code of conduct applicable to all of our employees, as well as a disclosure program and other applicable policies and procedures, but it is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business, including the imposition of significant fines or other sanctions.

Even if we receive marketing approval, we may not be successful in commercializing our investigational products.

We have no sales, marketing or distribution capabilities or experience. If any of our investigational products ultimately obtains regulatory approval, we, whether alone or in collaboration with Gilead for programs that we commercialize together, may not be able to effectively or successfully market the product due to a number of factors, including:

•the imposition by regulatory authorities of significant restrictions on a product’s indicated uses, marketing or distribution;

•the imposition by regulatory authorities of costly and time-consuming post-approval studies, post-market surveillance or additional clinical trials;

•our failure to establish sales and marketing capabilities;

•the failure of our products to achieve the degree of market acceptance by physicians, patients, hospitals, cancer treatment centers, healthcare payors and others in the medical community necessary for commercial success;

•unfavorable pricing regulations or third-party coverage and reimbursement policies; and

•inaccuracies in our estimates of the addressable patient population resulting in a smaller market opportunity than we believed.

If any of our investigational products for which we have or retain sales and marketing responsibilities are approved, we must either develop a sales and marketing organization, which would be expensive and time consuming, or outsource these functions to other third parties. We may be unable to recruit and retain adequate numbers of effective sales and marketing personnel, and if we enter into arrangements with third parties to perform sales, marketing and distribution services our product revenue or the profitability of these product revenue to us are likely to be lower than if we were to market and sell any medicines that we develop ourselves.

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Our or our collaborators’ inability to successfully market and sell any of our investigational products, if approved, could have a material adverse effect on our business and our overall financial condition.

Even if we receive marketing approval for one or more of our investigational products, our commercial success is dependent on obtaining coverage and reimbursement approval for a product from a government or other third-party payor, which coverage may be delayed or may not be sufficient to cover our costs.

Our commercial success is dependent on obtaining coverage and reimbursement approval for a product from a government or other third-party payor, which is a time-consuming and costly process that could require us and any collaborators to provide supporting scientific, clinical and cost effectiveness data for the use of our products to the payor. There may be significant delays in obtaining such coverage and reimbursement for newly approved products, and coverage may be more limited than the purposes for which the product is approved by the FDA or comparable foreign regulatory authorities. Moreover, eligibility for coverage and reimbursement does not imply that a product will be paid for in all cases or at a rate that covers our costs, including research, development, intellectual property, manufacture, sale and distribution expenses. Interim reimbursement levels for new products, if applicable, may also not be sufficient to cover our costs and may not be made permanent. Obtaining reimbursement for our products may be particularly difficult because of the higher prices often associated with branded therapeutics and therapeutics administered under the supervision of a physician. Additionally, our collaborators will be required to obtain coverage and reimbursement for any related companion diagnostics tests they develop separate and apart from the coverage and reimbursement we seek for our investigational products, once approved.

Reimbursement may also impact the demand for, and the price of, any product for which we obtain marketing approval. Assuming we obtain coverage for a given product by a third-party payor, the resulting reimbursement payment rates may not be adequate or may require co-payments that patients find unacceptably high. Patients who are prescribed medications for the treatment of their conditions, and their prescribing physicians, generally rely on third-party payors to reimburse all or part of the costs associated with those medications. Patients are unlikely to use our products unless coverage is provided and reimbursement is adequate to cover all or a significant portion of the cost of our products. Therefore, coverage and adequate reimbursement is critical to new product acceptance and we expect to experience pricing pressures in connection with the sale of any of our investigational products due to the trend toward managed healthcare, the increasing influence of health maintenance organizations, and additional legislative changes.

Our ability to obtain coverage and reimbursement approval for any of our investigational products, if approved, could have a material adverse effect on the demand for that investigational product, and on our business and our overall financial condition.

Even if our investigational products are approved by the FDA, they may never be approved or commercialized outside the United States, which would limit our ability to realize their full market potential.

In order to market any products outside the United States, we or our collaborators must establish and comply with numerous and varying regulatory requirements of other countries regarding safety and efficacy. Clinical trials conducted in one country may not be accepted by regulatory authorities in other countries, and regulatory approval in one country does not mean that regulatory approval will be obtained in any other country. For example, the approval of zimberelimab for the treatment of recurrent or refractory classical Hodgkin’s Lymphoma in China by Gloria Biosciences does not improve the chances of FDA approval for any BLA that we may submit for zimberelimab in the United States in any indication. Approval procedures vary among countries and can involve additional product testing and validation and additional administrative review periods. Seeking foreign regulatory approvals could result in significant delays, difficulties and costs for us or our collaborators and may require additional preclinical studies or clinical trials which would be costly and time consuming. Regulatory requirements can vary widely from country to country and could delay or prevent the introduction of our products in those countries. Satisfying these and other regulatory requirements is costly, time consuming, uncertain and subject to unanticipated delays. In addition, our or our collaborators’ failure to obtain regulatory approval in any country may delay or have negative effects on the process for regulatory approval in other countries. We do not have any investigational products approved for sale in any jurisdiction, including international markets, and we do not have experience in obtaining regulatory approval in international markets. If we or our collaborators fail to comply with regulatory requirements in international markets or fail to obtain and maintain required approvals, our ability to realize the full market potential of our products will be harmed.

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Any investigational products for which we intend to seek approval as biologic products may face competition sooner than anticipated.

The Biologics Price Competition and Innovation Act of 2009 (BPCIA) created an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with an FDA-licensed 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 licensed by the FDA. In addition, the approval of a biosimilar product may not be made effective by the FDA until twelve years from the date on which the reference product was first licensed. During this twelve-year period of exclusivity, another company may still market a competing version of the reference product if the FDA approves a full BLA for the competing product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of its product. The law is complex and is still being interpreted and implemented by the FDA. As a result, any such processes could have a material adverse effect on the future commercial prospects for our biological products.

Zimberelimab and domvanalimab are biological products and we may develop additional biological products in the future. We believe that any of our current and future investigational products approved as a biological product under a BLA should qualify for the twelve-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 products to be reference products for competing products, potentially creating the opportunity for biosimilar 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, could be substituted for any one of our reference products in a way that is similar to traditional generic substitution for non-biological products will depend on a number of marketplace and regulatory factors that are still developing.

Risks Related to our In-Licenses and Other Strategic Agreements

We are currently party to several in-license agreements under which we acquired rights to use, develop, manufacture and/or commercialize certain of our investigational products. If we breach our obligations under these agreements, we may be required to pay damages, lose our rights to these investigational products or both, which would adversely affect our business and prospects.

We rely, in part, on license and other strategic agreements, which subject us to various obligations, including diligence obligations with respect to development and commercialization activities, reporting and notification obligations, payment obligations for achievement of certain milestones and royalties on product sales, negative covenants and other material obligations. We may need to devote substantial time and attention to ensuring that we are compliant with our obligations under these agreements. If we fail to comply with the obligations under our license agreements or use the intellectual property licensed to us in an unauthorized manner, we may be required to pay damages and our licensors may have the right to terminate the license. If our license agreements are terminated, we may not be able to develop, manufacture, market or sell the products covered by our agreements and those being tested or approved in combination with such products. Such an occurrence could materially adversely affect the value of the investigational product being developed under any such agreement and any other investigational products being developed or tested in combination. For example, zimberelimab, which we in-licensed from WuXi Biologics, is intended to be used as the cornerstone of our combination strategy. Domvanalimab, which we in-licensed from Abmuno Therapeutics, is being evaluated in four registrational studies: ARC-10, PACIFIC-8 (in collaboration with AstraZeneca), STAR-121 (being operationalized by Gilead) and STAR-221. In the event we breach our license agreement with WuXi Biologics and/or Abmuno Therapeutics, and our license agreements are terminated, we would be unable to pursue our intra-portfolio combination strategy, or we would have to negotiate a new or reinstated agreement, which may not be available to us on equally favorable terms, or at all.

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

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We may not realize the benefits of any acquisitions, in-license or other collaborations or strategic alliances that we enter into.

We have entered into in-license agreements with multiple licensors and option agreements to enable the development and commercialization of our investigational products worldwide. In the future, we may seek to enter into acquisitions or additional licensing arrangements with third parties to expand our pipeline or that we believe will complement or augment our development and commercialization efforts with respect to our investigational products and any future investigational products that we may develop. These transactions can entail numerous operational and financial risks, including exposure to unknown liabilities, disruption of our business and diversion of our management’s time and attention in order to manage a collaboration or develop acquired products, investigational products or technologies, incurrence of substantial debt or dilutive issuances of equity securities to pay transaction consideration or costs, higher than expected collaboration, acquisition or integration costs, write-downs of assets or goodwill or impairment charges, increased amortization expenses, difficulty and cost in facilitating the collaboration or combining the operations and personnel of any acquired business, impairment of relationships with key suppliers, manufacturers or customers of any acquired business due to changes in management and ownership and the inability to retain key employees of any acquired business. As a result, if we enter into in-license, acquisition or collaboration agreements, or strategic partnerships, we may not be able to realize the benefit of such transactions if we are unable to successfully integrate them with our existing operations and company culture, which could delay our timelines or otherwise adversely affect our business.

We also cannot be certain that, following a strategic transaction or license, we will achieve the revenue or specific net income that justifies such transaction or such other benefits that led us to enter into the arrangement. For example, under the Gilead Collaboration Agreement, for each additional clinical program that Gilead exercises its option to, it will pay an option-exercise fee. Furthermore, we and Gilead will equally share global co-development costs for the joint development program, as well as profits and losses for the United States, subject to opt-out rights applicable to certain programs, and expense caps on our spending and true-up adjustments. If Gilead does not exercise its option to develop a program, our capital requirements relating to that development program will significantly increase and we may need to seek a new partner in order to develop and commercialize our investigational products from that program. Failure to realize the benefits of any collaborations or strategic alliances may further cause us to curtail the development of an investigational product, 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 planned sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to fund and undertake development or commercialization activities on our own, we will need to obtain additional expertise and additional capital, which may not be available to us on acceptable terms or at all. If we fail to enter into collaborations and do not have sufficient funds or expertise to undertake the necessary development and commercialization activities, we may not be able to further develop our investigational products or bring them to market and generate product sales revenue, which would harm our business prospects, financial condition and results of operations.

We may wish to acquire rights to future assets through in-licensing or may attempt to form collaborations in the future with respect to our investigational products, but may not be able to do so, which may cause us to alter or delay our development and commercialization plans.

The development and potential commercialization of our investigational products may require substantial additional capital to fund expenses. Pursuant to the Gilead Collaboration Agreement, Gilead has an exclusive option to acquire an exclusive license to all of our then-current and future clinical programs during the 10-year collaboration term. Given the breadth of the collaboration, our ability to form new collaborations in the future will be limited. If Gilead declines to exercise its option to a program, we may need to enter into new collaborations for such programs with companies that have more resources and experience than us. We may not be successful in these efforts because third parties may not view our investigational products as having the requisite potential to demonstrate safety and efficacy. If and when we collaborate with a third party for development and commercialization of an investigational product, we can expect to relinquish some or all of the control over the future success of that investigational product to the third party. 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. Those factors may include the following:

•the design or results of clinical trials;

•the likelihood of approval by the FDA or comparable foreign regulatory authorities;

•the potential market for the investigational product;

•the costs and complexities of manufacturing and delivering such investigational product to patients;

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•the potential of competing products;

•the existence of uncertainty with respect to our ownership of technology or other rights, which can exist if there is a challenge to such ownership without regard to the merits of the challenge; and

•industry and market conditions generally.

The collaborator may also consider alternative investigational products or technologies for similar indications that may be available to collaborate on and whether such a collaboration could be more attractive than the one with us for our investigational product. We may also be restricted under any license agreements by one or more negative covenants or otherwise. For example, we may be restricted from entering into agreements on certain terms or at all with potential collaborators. 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 and changes to the strategies of the combined company. As a result, we may not be able to negotiate collaborations on a timely basis, on acceptable terms, or at all. If we are unable to do so, we may have to curtail the development of such investigational product, reduce or delay one or more of our other development programs, delay the potential commercialization or reduce the scope of any planned sales or marketing activities for such investigational product, or increase our expenditures and undertake development, manufacturing or commercialization activities at our own expense and may be prevented from or limited in forming additional strategic collaborations. If we elect to increase our expenditures to fund development, manufacturing or commercialization activities on our own, we may need to obtain additional capital, which may not be available to us on acceptable terms or at all. If we do not have sufficient funds, we may not be able to further develop our investigational products or bring them to market and generate product revenue.

Risks Related to Intellectual Property

If we are unable to obtain and maintain sufficient intellectual property protection for our investigational products, or if the scope of the intellectual property protection is not sufficiently broad, our competitors could develop and commercialize products similar or identical to ours, and our ability to successfully commercialize our products 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 our investigational products and research programs. We seek to protect our proprietary position by filing patent applications in the United States and abroad related to our novel discoveries and technologies that are important to our business, however, we cannot predict:

•if and when patents may issue based on our patent applications;

•the scope of protection of any patent issuing based on our patent applications;

•whether the claims of any patent issuing based on our patent applications will protect our investigational products and their intended uses or prevent others from commercializing competitive technologies or products;

•whether or not third parties will find ways to invalidate or circumvent our patent rights;

•whether or not others will obtain patents claiming aspects similar to those covered by our patents and patent applications; and/or

•whether we will need to initiate litigation or administrative proceedings to enforce and/or defend our patent rights which will be costly whether we win or lose.

Obtaining and enforcing patents is expensive and time-consuming and we may not be able to file and prosecute all necessary or desirable patent applications at a reasonable cost or in a timely manner. Even if we successfully file and prosecute a patent application, we may not be able to maintain and/or enforce the issued patent. We may determine that filing or maintaining such a patent or any action to enforce a patent may be too high or not in the best interest of our company or our stockholders. It is also possible that we will fail to identify patentable aspects of our research and development results before it is too late to obtain patent protection. Although we enter into non-disclosure and confidentiality agreements with parties who have access to 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 these agreements and disclose such results before a patent application is filed, thereby jeopardizing our ability to seek patent protection.

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We also cannot be certain that the claims in our pending patent applications directed to our investigational products and/or technologies will be considered patentable by the U.S. Patent and Trademark Office (USPTO) or by patent offices in foreign countries. One aspect of the determination of patentability of our inventions depends on the scope and content of the “prior art,” information that was or is deemed available to a person of skill in the relevant art prior to the priority date of the claimed invention. There may be prior art of which we are not aware that may affect the patentability of our patent claims or, if issued, affect the validity or enforceability of a patent claim. Even if the patents do issue based on our patent applications, third parties may challenge the validity, enforceability or scope thereof, which may result in such patents being narrowed, invalidated or held unenforceable. Furthermore, even if they are unchallenged, patents in our portfolio may not adequately exclude third parties from practicing relevant technology or prevent others from designing around our claims. If the breadth or strength of our intellectual property position with respect to our investigational products is threatened, it could dissuade companies from collaborating with us to develop and threaten our ability to commercialize our investigational products. In the event of litigation or administrative proceedings, we cannot be certain that the claims in any of our issued patents will be considered valid by courts in the United States or foreign countries.

In the future, we may need to obtain additional licenses of third-party technology that may not be available to us or are available only on commercially unreasonable terms, and which may cause us to operate our business in a more costly or otherwise adverse manner than anticipated.

From time to time we may be required to license technology from additional third parties to further develop or commercialize our investigational products. Should we be required to obtain licenses to any third-party technology, including any such patents required to manufacture, use or sell our investigational products, such licenses may not be available to us on commercially reasonable terms, or at all. The inability to obtain any third-party license required to develop or commercialize any of our investigational products could cause us to abandon any related efforts, which could seriously harm our business and operations.

We may become involved in lawsuits alleging that we have infringed the intellectual property rights of third parties or to protect or enforce our patents or other intellectual property, which litigation could be expensive, time consuming and adversely affect our ability to develop or commercialize our investigational products.

The coverage of patents is subject to interpretation by the courts, and the interpretation is not always uniform. There is a substantial amount of intellectual property litigation in the biotechnology and pharmaceutical industries, and we may become party to, or threatened with, litigation or other adversarial proceedings regarding intellectual property rights with respect to our products candidates. Third parties may assert infringement claims against us based on existing or future intellectual property rights. For example, we are aware of certain patents owned or licensed by Bristol-Myers Squibb having claims directed broadly to treating cancer with anti-PD-1 antibodies (the BMS Patents), which expire in 2023 and 2024. The BMS Patents have been and may in the future be the subject of litigation. In addition, we are aware of certain patents held by Genentech relating to methods of using an anti-PD-1 or anti-PD-L1 antibody in combination with an anti-TIGIT antibody for the treatment of cancer (the Genentech Patents), which expire in 2034, two of which were recently statutorily disclaimed. These patents are, or have been, the subject of post-grant proceedings at the United States Patent and Trademark Office “USPTO” and other global patent offices. If the validity of the BMS Patents and Genentech Patents are upheld following all challenges, and if we receive regulatory approval for zimberelimab prior to expiration of the BMS Patents or domvanalimab in combination with zimberelimab in a territory with standing intellectual property rights prior to expiration of the BMS or Genentech Patents, then we may need to delay commercialization or we may need to obtain a license, which license may not be available on commercially reasonable terms, or at all. If we were sued for patent infringement, we would need to demonstrate that our investigational products, products or methods either do not infringe the patent claims of the relevant patent or that the patent claims are invalid or unenforceable, and we may not be able to do this. Proving invalidity may be difficult. For example, in the United States, proving invalidity in court requires a showing of clear and convincing evidence to overcome the presumption of validity enjoyed by issued patents. If we are found to infringe a third party’s intellectual property rights, we could be forced, including by court order, to cease developing, manufacturing or commercializing the infringing investigational product or product. Alternatively, we may be required to obtain a license from such third party in order to use the infringing technology and continue developing, manufacturing or marketing the infringing investigational product. However, we may not be able to obtain any required license on commercially reasonable terms or at all. Even if we were able to obtain a license, it could be non-exclusive, thereby giving our competitors access to the same technologies licensed to us. In addition, we could be found liable for monetary damages, including treble damages and attorneys’ fees if we are found to have willfully infringed a patent. A finding of infringement could prevent us from commercializing our investigational products or force us to cease some of our business operations, which could materially harm our business.

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In addition, we may find that competitors are infringing our patents, trademarks, copyrights or other intellectual property. To counter infringement or unauthorized use, we may be required to file infringement claims, which can be expensive and time consuming and divert the time and attention of our management and scientific personnel. Any claims we assert against perceived infringers could provoke these parties to assert counterclaims against us alleging that we infringe their patents, in addition to counterclaims asserting that our patents are invalid or unenforceable, or both. In any patent infringement proceeding, there is a risk that a court will decide that a patent of ours is invalid or unenforceable, in whole or in part, and that we do not have the right to stop the other party from using the invention at issue. There is also a risk that, even if the validity of such patents is upheld, the court will construe the patent’s claims narrowly or decide that we do not have the right to stop the other party from using the invention at issue on the grounds that our patent claims do not cover the invention. An adverse outcome in a litigation or proceeding involving our patents could limit our ability to assert our patents against those parties or other competitors, and may curtail or preclude our ability to exclude third parties from making and selling similar or competitive products. Any of these occurrences could adversely affect our competitive business position, business prospects and financial condition. Similarly, 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 which 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. 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 litigation. There could also be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have a material adverse effect on the price of shares of our common stock. Moreover, we cannot assure you that we will have sufficient financial or other resources to defend or pursue such litigation, which typically last for years before they are concluded. Even if we are successful in these proceedings, we may incur substantial costs and the time and attention of our management and scientific personnel could be diverted in pursuing these proceedings, which could have a material adverse effect on our business and operations. In addition, we may not have sufficient resources to bring these actions to a successful conclusion.

We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties.

We could in the future be subject to claims that we or our employees have inadvertently or otherwise used or disclosed alleged trade secrets or other confidential information of former employers or competitors. Although we try to ensure that our employees and consultants do not use the intellectual property, proprietary information, know-how or trade secrets of others in their work for us, we may become subject to claims that we caused an employee to breach the terms of his or her non-competition or non-solicitation agreement, or that we or these individuals have, inadvertently or otherwise, used or disclosed the alleged trade secrets or other proprietary information of a former employer or competitor.

While we may litigate to defend ourselves against these claims, even if we are successful, litigation could result in substantial costs and could be a distraction to management. If our defenses to these claims fail, in addition to requiring us to pay monetary damages, a court could prohibit us from using technologies or features that are essential to our investigational products, if such technologies or features are found to incorporate or be derived from the trade secrets or other proprietary information of the former employers. Moreover, any such litigation or the threat thereof may adversely affect our reputation, our ability to form strategic alliances or sublicense our rights to collaborators, engage with scientific advisors or hire employees or consultants, each of which would have an adverse effect on our business, results of operations and financial condition.

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We may not be able to protect our intellectual property rights outside of the U.S.

Patents are of national or regional effect, and filing, prosecuting and defending patents on all of our investigational products throughout the world would be prohibitively expensive. As such, 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. Further, the legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents and other intellectual property protection, particularly those relating to pharmaceuticals or biologics, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our proprietary rights generally. In addition, certain developing countries, including China and India, have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties. Further, we file patent applications in Russia and the Eurasian patent office, which is headquartered in Moscow. Sanctions against Russia may make it difficult to file and maintain patents in these countries, and Russia has begun taking actions against "unfriendly" countries, including the U.S., which may adversely affect the scope of and/or our ability to enforce our intellectual property rights. In any of these countries, we and our licensors may have limited remedies if patents are infringed or if we or our licensors are compelled to grant a license to a third party, which could materially diminish the value of those patents. This could limit our potential revenue opportunities. Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license.

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

As is the case with other biopharmaceutical companies, our success is heavily dependent on intellectual property, particularly patents. However, the patent position of biopharmaceutical companies generally is highly uncertain, involves complex legal and factual questions and has in recent years been the subject of much litigation, resulting in court decisions, including Supreme Court decisions, which have increased uncertainties as to the ability to obtain and enforce patent rights in the future. Changes in either the patent laws or interpretation of the patent laws in the United States and other countries could increase the uncertainties and costs. For example, in September 2011 the Leahy-Smith America Invents Act (the America Invents Act) was signed into law and included a number of significant changes to U.S. patent law as then existed. These include provisions that affect the way patent applications are prosecuted, redefine prior art and provide more efficient and cost-effective avenues for competitors to challenge the validity of patents. 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. After March 2013, under the America Invents Act, the United States transitioned to a first inventor to file system in which, assuming that the other statutory requirements are met, the first inventor to file a patent application will be entitled to the patent on an invention regardless of whether a third party was the first to invent the claimed invention. However, the America Invents Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have a material adverse effect on our business, financial condition, results of operations and prospects.

The U.S. Supreme Court has ruled on several patent cases in recent years, either narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations. Depending on future actions by the U.S. Congress, the U.S. courts, the USPTO and the relevant law-making bodies in other countries, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce our existing patents and patents that we might obtain in the future.

We may rely on trade secret and proprietary know-how which can be difficult to trace and enforce and, 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 some of our technology and investigational products, we may also rely on trade secrets, including unpatented know-how, technology and other proprietary information, to maintain our competitive position. Elements of our investigational product, including processes for their preparation and manufacture, may involve proprietary know-how, information, or technology that is not covered by patents, and thus for these aspects we may consider trade secrets and know-how to be our primary intellectual property. Any disclosure, either intentional or unintentional, by our employees, third parties with which we share our facilities or third-party consultants and vendors that we engage to perform research, clinical trials or manufacturing activities, or misappropriation by third parties (such as through a cybersecurity breach) of our trade secrets or proprietary information could enable competitors to duplicate or surpass our technological achievements, thus eroding our competitive position in our market.

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Trade secrets and know-how can be difficult to protect. We require our employees to enter into written employment agreements containing provisions of confidentiality and obligations to assign to us any inventions generated in the course of their employment. We and any third parties with which we share facilities enter into written agreements that include confidentiality and intellectual property obligations to protect each party’s property, potential trade secrets, proprietary know-how, and information. We further seek to protect our potential trade secrets, proprietary know-how, and information in part, by entering into non-disclosure and confidentiality agreements with parties who are given access to them, such as our corporate collaborators, outside scientific collaborators, contract research organizations, contract manufacturers, consultants, advisors and other third parties. With our consultants, contractors, and outside scientific collaborators, these agreements typically include invention assignment obligations. Despite these efforts, any of these parties may breach the agreements and disclose our proprietary information, including our trade secrets, and we may not be able to obtain adequate remedies for such breaches. 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 harmed.

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

We may be subject to claims that former employees, collaborators or other third parties have an interest in our patents or other intellectual property as an inventor or co-inventor. The failure to name the proper inventors on a patent application can result in the patents issuing thereon being unenforceable. Inventorship disputes may arise from conflicting views regarding the contributions of different individuals named as inventors, the effects of foreign laws where foreign nationals are involved in the development of the subject matter of the patent, conflicting obligations of third parties involved in developing our investigational products or as a result of questions regarding co-ownership of potential joint inventions. Litigation may be necessary to resolve these and other claims challenging inventorship and/or ownership. Alternatively, or additionally, we may enter into agreements to clarify the scope of our rights in such intellectual property. If we 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, valuable intellectual property. Such an outcome could have a material adverse effect on our business. 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.

Patent terms may be inadequate to protect our competitive position on our investigational products for an adequate amount of time.

Patent rights are of limited duration. Given the amount of time required for the development, testing and regulatory review of new investigational products, patents protecting such candidates might expire before or shortly after such investigational products are commercialized. Even if patents covering our investigational products are obtained, once the patent life has expired for a product, we may be open to competition from biosimilar or generic products. A patent term extension based on regulatory delay may be available in the United States. However, only a single patent can be extended for each marketing approval, and any patent can be extended only once, for a single product. Moreover, the scope of protection during the period of the patent term extension does not extend to the full scope of the claim, but instead only to the scope of the product as approved. Laws governing analogous patent term extensions in foreign jurisdictions vary widely, as do laws governing the ability to obtain multiple patents from a single patent family. Additionally, we may not receive an extension if we fail to apply within applicable deadlines, fail to apply prior to expiration of relevant patents or otherwise fail to satisfy applicable requirements. If we are unable to obtain patent term extension or restoration, or the term of any such extension is less than we request, the period during which we will have the right to exclusively market our product will be shortened and our competitors may obtain approval of competing products following our patent expiration, and our revenue could be reduced, possibly materially.

Risks Related to our Business Operations

We expect to expand our business operations and, as a result, we may encounter difficulties in managing our growth, which could disrupt our operations.

We expect to grow our business operations, including, if any of our investigational products receives marketing approval, adding employees in sales and marketing. To manage our anticipated future growth, we must:

•identify, recruit, integrate, maintain and motivate additional qualified personnel;

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•manage our development efforts effectively, including the initiation and conduct of clinical trials for our investigational products; and

•improve our operational, financial and management controls, reporting systems and procedures.

Our future financial performance and our ability to develop, manufacture and commercialize our investigational products will depend, in part, on our ability to effectively manage any future growth, and our management may also have to divert financial and other resources, and a disproportionate amount of its attention away from day-to-day activities in order to devote a substantial amount of time, to managing these growth activities.

If we are not able to effectively expand our organization by hiring new employees and expanding our groups of consultants and contractors, we may not be able to successfully implement the tasks necessary to further develop and commercialize our investigational products and, accordingly, may not achieve our research, development and commercialization goals.

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

Our ability to compete in the highly competitive biopharmaceuticals industry depends upon our ability to attract, retain and motivate highly skilled and experienced personnel with scientific, medical, regulatory, manufacturing and management skills and experience. We conduct our operations in the San Francisco Bay Area, a region that is home to many other biopharmaceutical companies as well as many academic and research institutions, resulting in fierce competition for qualified personnel and rapidly increasing wages. Our industry also has experienced a high rate of turnover in recent years. While we have expanded a number of our in-office roles to permit remote work arrangements, allowing us to seek talent from outside the San Francisco Bay Area, we still may not be able to attract or retain qualified personnel in the future due to the intense competition for a limited number of qualified personnel among biopharmaceutical companies. Many of the other biopharmaceutical companies against which we compete have greater financial and other resources, different risk profiles and a longer history in the industry than we do. Our competitors may provide higher compensation, more diverse opportunities and/or better opportunities for career advancement. Any or all of these competing factors may limit our ability to continue to attract and retain high quality personnel, which could negatively affect our ability to successfully develop and commercialize our investigational products and to grow our business and operations as currently contemplated.

We are highly dependent on the services of our founders, Terry Rosen, Ph.D., who serves as our Chief Executive Officer, and Juan Jaen, Ph.D., who serves as our President.

We are highly dependent on the services of our founders, Terry Rosen, Ph.D., who serves as our Chief Executive Officer, and Juan Jaen, Ph.D., who serves as our President. Although we have entered into employment agreements with them, they are not for a specific term and each of them may terminate their employment with us at any time, though we are not aware of any present intention of either of these individuals to leave us.

Drs. Rosen and Jaen have significant experience identifying and developing biopharmaceuticals. We believe that their drug discovery and development experience, and overall biopharmaceutical company management experience, would be difficult to replace. However, the historical results, past performance and/or acquisitions of companies with which they were affiliated do not necessarily predict or guarantee similar results for our company. Further, Drs. Rosen and Jaen have certain other business and personal commitments outside of serving as the Chief Executive Officer and President of Arcus, including serving on the boards of other companies and foundations, which may result in diversion of their focus and attention on our company.

We face substantial competition, which may result in others discovering, developing or commercializing products more quickly or marketing them more successfully than us. If their investigational products are shown to be safer or more effective than ours, then our commercial opportunity will be reduced or eliminated.

We compete in the segments of the pharmaceutical, biotechnology and other related markets that develop immunotherapies for the treatment of cancer, which is highly competitive with rapidly changing standards of care. As such, our commercial opportunity could be reduced or eliminated if our competitors develop and commercialize products that are safer, more effective, have fewer or less severe side effects, are more convenient, or are less expensive than any products that we may develop or that would render any products that we may develop obsolete or non-competitive. Our competitors also may obtain marketing approval for their products more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market.

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We are aware of several pharmaceutical companies developing products in the same class as our investigational products, some of which are further along in development than our corresponding assets. For additional information regarding our competitors, see “Item 1. Business—Competition” in our Annual Report on Form 10-K filed with the SEC on February 28, 2023.

As more investigational products within a particular class of drugs proceed through clinical development to regulatory review and approval, the amount and type of clinical data that may be required by regulatory authorities may increase or change. Consequently, the results of our clinical trials for investigational products in that class will likely need to show a risk benefit profile that is competitive with or more favorable than those products and investigational products in order to obtain marketing approval or, if approved, a product label that is favorable for commercialization. If the risk benefit profile is not competitive with those products or investigational products, or if the approval of other agents for an indication or patient population significantly alters the standard of care with which we tested our investigational products, we may have developed a product that is not commercially viable, that we are not able to sell profitably or that is unable to achieve favorable pricing or reimbursement. In such circumstances, our future product revenue and financial condition would be materially and adversely affected.

Our internal information technology systems, and those of our third-party CROs and other third parties upon which we rely, are subject to failure, security breaches and other disruptions, which could result in a material disruption of our investigational products’ development programs, jeopardize sensitive information, prevent us from accessing critical information or result in a loss of our assets, and potentially expose us to notification obligations, loss, liability or reputational damage and otherwise adversely affect our business.

We are increasingly dependent upon information technology systems, infrastructure and data to operate our business. In the ordinary course of business, we collect, store and transmit confidential information, including but not limited to intellectual property, proprietary business information and personal information. It is critical that we do so in a secure manner to maintain the confidentiality, integrity and availability of such confidential information. We also have outsourced elements of our operations to third parties, and as a result we manage a number of third-party contractors who have access to our confidential information.

Despite the implementation of security measures, given their size and complexity and the increasing amounts of confidential information that they maintain, our internal information technology systems and those of our third-party CROs and other third parties upon which we rely are vulnerable to breakdown or other damage or interruption from service interruptions, system malfunction, natural disasters, terrorism, war and telecommunication and electrical failures, as well as security breaches from inadvertent or intentional actions by our employees, contractors, consultants, business partners, and/or other third parties, or from cyberattacks by malicious third parties (including the deployment of harmful malware, ransomware, denial-of-service attacks, social engineering and other means to affect service reliability and threaten the confidentiality, integrity and availability of information and other assets), which may compromise our system infrastructure, lead to data leakage, impair key business processes or other critical business operations, delay our development programs, or result in the loss of assets or other liability. We have monitoring systems in place and have detected at least one intrusion into our computer systems and attempts to exfiltrate our data. Although our investigation in each case indicates that it did not have a material adverse effect on our operations nor result in any compromise of our information, there can be no assurance of a similar result in the future. Our reliance on internet technology and the number of our employees who are working remotely has increased the opportunities for cybercriminals to exploit vulnerabilities. Overall, there has been a significant increase in fraud schemes, including a successful social engineering attack against us through one of our employees. We cannot assure you that our data protection efforts and our investment in information technology will prevent breakdowns, data leakages, breaches in our systems or other cyber incidents that could have a material adverse effect upon our reputation, business, operations or financial condition.

Furthermore, as the cyber threat landscape evolves, these attacks are growing in frequency, sophistication and intensity, and becoming increasingly difficult to detect. There can be no assurance that we and our third-party CROs and other third parties upon which we rely will be successful in detecting, preventing or fully recovering systems or data from all breakdowns, service interruptions, attacks or breaches of systems that could adversely affect our business and operations and/or result in the loss or disclosure of critical or sensitive data or other assets, which could result in financial, legal, business or reputational harm to us. Ransomware attacks have risen dramatically and we may be forced to pay to unlock our data and information, re-access our systems and resume our ability to conduct business operations. The loss of clinical trial data for our investigational products could significantly increase our costs to recover or reproduce the data and result in delays in our development programs, impair our ability to obtain marketing approval and reduce the commercial opportunity for our investigational products.

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Moreover, significant disruptions of our internal information technology systems or security breaches could result in the loss, misappropriation, and/or unauthorized access, use, or disclosure of, or the prevention of access to, confidential information (including trade secrets or other intellectual property, proprietary business information, and personal information), which could result in financial, legal, business, and reputational harm to us. In particular, any such event that leads to unauthorized access, use, or disclosure of personal information, including personal information regarding our clinical trial subjects or employees, could harm our reputation directly, compel us to comply with federal and/or state breach notification laws and foreign law equivalents, subject us to mandatory corrective action, and otherwise subject us to liability under laws and regulations that protect the privacy and security of personal information, which could result in significant legal and financial exposure and reputational damages that could potentially have an adverse effect on our business.

Although we maintain insurance coverage to insure against losses suffered as a result of malicious intrusions and cyberattacks, such coverage may be insufficient to fully compensate us for the loss or there may be disputes with our insurers about the availability of insurance coverage for our claims. Cyber insurance may become increasingly difficult to maintain and we may not be able to maintain coverage at a reasonable cost or in an amount adequate to compensate for any loss or satisfy any liability that may arise.

Unfavorable global economic, political and trade conditions could adversely affect our business, financial condition or results of operations and may exacerbate the effects of the risks described herein.

Current global economic conditions are highly volatile due to a number of reasons, including geopolitical instability, such as the ongoing military conflict between Russia and Ukraine and the recent eruption of war between Israel and Hamas, rising inflation that has increased our operating expenses and disruptions in the capital and credit markets that may reduce our ability to raise additional capital when needed on acceptable terms, if at all.

Emerging international trade relations may also adversely impact our operations and/or financial condition by limiting or preventing the activities of third parties that we engage or increasing the cost of our operations. For example, WuXi Biologics, located in China, is our sole manufacturer of our investigational biologics, including zimberelimab, domvanalimab. In addition, if tariffs were to be imposed on the investigational products they manufacture for us, such tariffs would have an adverse impact on our operating results and financial condition.

Furthermore, the current inflationary environment related to increased aggregate demand and supply chain constraints has increased our operating expenses and may continue to affect our operating expenses. Economic conditions may also strain our suppliers, possibly resulting in supply disruptions that impact our ongoing clinical trials and other operations. A significant worsening of global economic conditions could materially increase these risks we face.

Any new or prolonged downturn of global economic conditions could harm our business and we cannot anticipate all of the ways in which the current economic climate and financial market conditions could adversely impact our business.

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

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

•our customers’ ability to obtain reimbursement for our investigational products in foreign markets;

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

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

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

•import or export licensing requirements;

•longer accounts receivable collection times;

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•longer lead times for shipping;

•language barriers for technical training;

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

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

•foreign currency exchange rate fluctuations; and

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

Foreign sales of our investigational products could also be adversely affected by the imposition of governmental controls, political and economic instability, trade restrictions and changes in tariffs.

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

Our headquarters and main research facility are located in the San Francisco Bay Area, which in the past has experienced severe earthquakes and fires. In addition, fires and other natural disasters may increase in frequency and severity over time due to climate change. If these earthquakes, fires, other natural disasters, terrorism and similar unforeseen events beyond our control prevented us from using all or a significant portion of our headquarters or research facility, it may be difficult or, in certain cases, impossible for us to continue our business for a substantial period of time. We do not have a disaster recovery or business continuity plan in place and may incur substantial expenses as a result of the absence or limited nature of our internal or third-party service provider disaster recovery and business continuity plans, which, particularly when taken together with our lack of earthquake insurance, could have a material adverse effect on our business. Furthermore, integral parties in our supply chain are operating from single sites, increasing their vulnerability to natural disasters or other sudden, unforeseen and severe adverse events. If such an event were to affect our supply chain, it could have a material adverse effect on our ability to conduct our clinical trials, our development plans and business.

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

We have incurred substantial losses during our history and our ability to generate profits in the future is uncertain. Unused net operating loss carryforwards (NOLs) for the tax year ended December 31, 2017 and prior tax years will carry forward to offset future taxable income, if any, until such unused NOLs expire. Unused NOLs generated after December 31, 2017, under current tax law, will not expire. Our NOLs may be carried forward indefinitely. In addition, the future deductibility of such NOLs will be limited to 80% of current year taxable income in any given year.

Both our current and our future unused losses (and tax credit carryforwards) may be subject to further limitation under Sections 382 and 383 of the Internal Revenue Code (IRC) of 1986, as amended, if we undergo an “ownership change,” generally defined as a greater than 50 percentage point change (by value) in its equity ownership by certain stockholders over a three-year period. We performed an analysis under IRC Section 382 and 383 through October 31, 2020 with respect to our net operating loss and credit carryforwards. We concluded that an ownership change, as defined under IRC Section 382, occurred in previous years but that such ownership change did not result in the expiration of our net operating loss or credit carryforwards prior to utilization. We may incur additional ownership changes in the future in connection with any equity issuance, including any additional issuances to Gilead. If we experience any such ownership change, we may be limited in our ability to use our net operating loss and credit carryforwards and be required to make material cash tax payments.

Similar provisions of state tax law may also apply to limit our use of accumulated state tax attributes. In addition, at the state level, there may be periods during which the use of NOLs is suspended or otherwise limited. For example, while California recently enacted a franchise tax law restoring the usability of California state NOLs to offset taxable income for tax years beginning on January 1, 2022, previous law significantly limited the use of California state NOLs for taxable years 2020 and 2021. Similar laws in the future could accelerate or permanently increase state taxes owed. Therefore, even if we attain sustained profitability, we may be unable to use all or a material portion of our NOLs and other tax attributes, which could adversely affect our future cash flows.

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Changes in tax laws and regulations or exposure to additional tax liabilities could adversely affect our financial results.

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, or IRS, and the U.S. Treasury Department. Changes to tax laws (which changes may have retroactive application) could adversely affect us or holders of our common stock. In recent years, many such changes have been made and changes are likely to continue to occur in the future. For example, beginning in 2022, the Tax Cuts and Jobs Act of 2017 eliminates the option to currently deduct research and development expenditures and requires taxpayers to capitalize and amortize U.S. based and non-U.S. based research and development expenditures over five and fifteen years, respectively, pursuant to IRC Section 174. We cannot predict whether, when, in what form, or with what effective dates, tax laws, regulations and rulings may be enacted, promulgated or issued, which could result in an increase in our or our stockholders’ tax liability or require changes in the manner in which we operate in order to minimize or mitigate any adverse effects of changes in tax law.

Risks Related to Our Industry

Product liability lawsuits against us could cause us to incur substantial liabilities and could limit our commercialization of any investigational products that we may develop.

We face an inherent risk of product liability exposure related to the testing of our investigational products in human clinical trials and will face an even greater risk if we commercially sell any products that we may develop. If we cannot successfully defend ourselves against claims that our investigational products or products caused injuries, we could incur substantial liabilities. Regardless of merit or eventual outcome, product liability claims may result in:

•delay or termination of clinical trials;

•decreased demand for any investigational products or products that we may develop;

•injury to our reputation and significant negative media attention;

•withdrawal of clinical trial subjects;

•initiation of investigations by regulators;

•significant costs to defend the related litigation and diversion of management’s time and our resources;

•substantial monetary awards to study subjects or patients;

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

•loss of revenue; and

•the inability to commercialize any products that we may develop.

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

Failure to comply with health and data protection laws and regulations could lead to government enforcement actions (which could include civil or criminal penalties), private litigation, and/or adverse publicity and could negatively affect our operating results and business.

We and any potential collaborators may be subject to federal, state, and foreign data protection laws and regulations (i.e., laws and regulations that address privacy and data security). In the United States, numerous federal and state laws and regulations, including federal health information privacy laws, state data breach notification laws, state health information privacy laws, and federal and state consumer protection laws (e.g., Section 5 of the FTC Act), that govern the collection, use, disclosure, and protection of health-related and other personal information could apply to our operations or the operations of our collaborators. In addition, we may obtain health information from third parties (including research institutions from which we obtain clinical trial data) that are subject to privacy and security requirements under federal Health Insurance Portability and Accountability Act of 1996 (HIPAA) as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 (HITECH). Depending on the facts and circumstances, we could be subject to significant penalties if we violate HIPAA.

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The legislative and regulatory landscape for privacy and data security continues to evolve, and we expect that there will continue to be new proposed laws, regulations and industry standards relating to privacy and data security in the United States, the EU and other jurisdictions. This increased focus on privacy and data security issues may negatively affect our operating results and our business. For example, the California Consumer Privacy Act of 2018 (CCPA), which took effect on January 1, 2020 and was amended by the California Privacy Rights Act of 2020 effective on January 1, 2023, gives California residents expanded rights to access, correct and require deletion of their personal information, limit disclosure of sensitive personal information, opt out of certain personal information sharing, and receive detailed information about how their personal information is used. In addition, the CCPA authorizes private lawsuits to recover statutory damages for certain data breaches. While it exempts some data regulated by HIPAA and certain clinical trials data, the CCPA may increase our compliance costs and potential liability with respect to other personal information we collect about California residents. Some observers note that the CCPA could mark the beginning of a trend toward more stringent privacy legislation in the U.S., which could increase our potential liability and adversely affect our business.

Foreign data protection laws also apply to health-related and other personal data obtained outside the United States. In the European Union, Regulation (EU) 2016/679 (General Data Protection Regulation) took effect in May 2018 and imposes, in some cases, stricter obligations than data protection laws in the United States on the use of health-related and other personal data. These requirements include the obligation to appoint data protection officers in certain circumstances, rights for individuals to be “forgotten” and to data portability, and the obligation to make public notification of significant data breaches. Under the General Data Protection Regulation, data protection authorities can also impose administrative fines of up to 4% of our total worldwide turnover or up to €20 million (whichever is higher). In addition, the General Data Protection Regulation only permits the transfer of personal data outside the European Economic Area (EEA) to countries that offer a level of data protection deemed adequate by the European Commission, unless an approved data transfer mechanism is in place. One such mechanism was invalidated by the European Court of Justice, adding to the complexity of transferring personal data outside the EEA. The General Data Protection Regulation increases our responsibility and liability in relation to personal data that we process, and we must put in place additional mechanisms to ensure compliance with the new EU data protection rules.

Failure to comply with U.S. and foreign data protection laws and regulations could result in government enforcement actions (which could include civil or criminal penalties), private litigation, and/or adverse publicity and could negatively affect our operating results and business. Moreover, clinical trial subjects about whom we or our potential collaborators obtain information, as well as the providers who share this information with us, may contractually limit our ability to use and disclose the information. Claims that we have violated individuals’ privacy rights, failed to comply with data protection laws, or breached our contractual obligations, even if we are not found liable, could be expensive and time-consuming to defend and could result in adverse publicity that could harm our business.

Our business operations expose us to broadly applicable fraud and abuse, transparency, government price reporting, and other healthcare laws and regulations. If we are unable to comply, or have not fully complied, with such laws, we could face substantial penalties.

Our operations are subject, either directly or indirectly through our customers and third-party payors, to various U.S. federal and state health care laws, including fraud and abuse, transparency and other healthcare laws and regulations, and similar laws in other jurisdictions in which we conduct our business. These laws may impact, among other things, our research and proposed sales, marketing and education programs and constrain the business of financial arrangements and relationships with healthcare providers, physicians and other parties through which we market, sell and distribute our products for which we obtain marketing approval. The laws that may affect our ability to operate include, but are not limited to the federal Anti-Kickback Statute; federal civil and criminal false claims laws, such as the False Claims Act (FCA); HIPAA; federal and state consumer protection and unfair competition laws; the federal transparency requirements under the Physician Payments Sunshine Act; state and foreign law equivalents of each of these federal laws; and state and foreign laws that require pharmaceutical companies to implement compliance programs. Many of these laws are discussed in detail in “Item 1. Business—Government Regulation—Other U.S. Healthcare Laws and Compliance Requirements” in our Annual Report on Form 10-K filed with the SEC on February 28, 2023.

The scope and enforcement of each of these laws is uncertain and subject to rapid change in the current environment of healthcare reform. Federal and state enforcement bodies have continued 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. Responding to investigations can be time-and resource-consuming and can divert management’s attention from the business. Any such investigation or settlement could increase our costs or otherwise have an adverse effect on our business.

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Ensuring that our business arrangements with third parties comply with applicable healthcare laws and regulations will likely be costly. We have entered into consulting and advisory board arrangements with physicians and other healthcare providers, including some who could influence the use of our investigational products, if approved. Because of the complex and far-reaching nature of these laws, regulatory agencies may view these transactions as prohibited arrangements that must be restructured, or discontinued, or for which we could be subject to other significant civil, criminal and administrative penalties such as fines, disgorgement, imprisonment, exclusion from government funded healthcare programs, such as Medicare and Medicaid, contractual damages, reputational harm, diminished profits and future earnings, 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, and the curtailment or restructuring of our operations, any of which could substantially disrupt our operations. If any of the physicians or other healthcare providers or entities with which we expect to do business is found to be not in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs.

Changes in healthcare law and implementing regulations, as well as changes in healthcare policy, may impact our business in ways that we cannot currently predict, and may have a significant adverse effect on our business and results of operations.

In the United States and some foreign jurisdictions, there have been, and continue to be, several legislative and regulatory changes and proposed changes regarding the healthcare system that could prevent or delay marketing approval of investigational products, restrict or regulate post-approval activities, and affect the ability to profitably sell investigational products for which marketing approval is obtained. Among policy makers and payors in the United States and elsewhere, there is significant interest in promoting changes in healthcare systems with the stated goals of containing healthcare costs, improving quality and/or expanding access. In the United States, the pharmaceutical industry has been a particular focus of these efforts and has been significantly affected by major legislative initiatives. For example, on August 16, 2022, President Biden signed into law the Inflation Reduction Act of 2022 (IRA), which, among other things, (1) directs the U.S. Department of Health and Human Services to negotiate the price of certain single-source drugs and biologics covered under Medicare and (2) imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation. The IRA also extends enhanced subsidies for individuals purchasing health insurance coverage in Affordable Care Act marketplaces through plan year 2025 and eliminates the “donut hole” under the Medicare Part D program by significantly lowering the beneficiary maximum out-of-pocket cost and through a newly established manufacturer discount program. These provisions take effect progressively starting in fiscal year 2023. On August 29, 2023, HHS announced the list of the first ten drugs that will be subject to price negotiations, although the Medicare drug price negotiation program is currently subject to legal challenges. The United States Department of Health and Human Services has and will continue to issue and update guidance as these programs are implemented. It is currently unclear how the IRA will be implemented but is likely to have a significant impact on the pharmaceutical industry. We expect that other healthcare reform measures may be adopted in the future, and that any such health reform measures could have an adverse effect on our business and/or results of operation.

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.

U.S. and foreign anti-corruption, anti-money laundering, export control, sanctions, and other trade laws and regulations (collectively, Trade Laws) prohibit, among other things, 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 or government-affiliated hospitals, universities, and other organizations. We also expect our non-U.S. activities to increase over time. We expect to rely on third parties for research, preclinical studies, and clinical trials and/or to obtain necessary permits, licenses, patent registrations, and other marketing approvals. 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.

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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, and the third parties with which we share our facilities, 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. Each of our operations involve the use of hazardous and flammable materials, including chemicals and biological and radioactive materials. Each of our operations also produce hazardous waste products. We generally contract with third parties for the disposal of these materials and wastes. We cannot eliminate the risk of contamination or injury from these materials. We could be held liable for any resulting damages in the event of contamination or injury resulting from the use of hazardous materials by us or the third parties with which we share our facilities, and any liability could exceed our resources. We also could incur significant costs associated with civil or criminal fines and penalties.

Although we maintain workers’ compensation insurance to cover us for costs and expenses, we may incur due to injuries to our employees resulting from the use of hazardous materials, this insurance may not provide adequate coverage against potential liabilities. We do not maintain insurance for environmental liability or toxic tort claims that may be asserted against us in connection with our storage or disposal of biological, hazardous or radioactive materials.

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 and development. Failure to comply with these laws and regulations also may result in substantial fines, penalties or other sanctions.

Risks Related to Owning our Common Stock

The stock price of our common stock has been and may continue to be volatile or may decline regardless of our operating performance.

The market price of our common stock has fluctuated and may fluctuate significantly in response to numerous factors, many of which are beyond our control, including:

•overall performance of the equity markets;

•our operating performance and the performance of other similar companies;

•results from our ongoing clinical trials and future clinical trials with our current and future investigational products or of our competitors;

•changes in our projected operating results that we provide to the public, our failure to meet these projections or changes in recommendations by securities analysts that elect to follow our common stock;

•regulatory, trade or legal developments in the United States and other countries, including changes in tariffs or other trade restrictions and the changes in the structure of healthcare payment systems;

•the level of expenses related to future investigational products or clinical development programs;

•our failure to achieve product development goals in the timeframe we announce;

•announcements of acquisitions, strategic alliances or significant agreements by us or by our competitors;

•recruitment or departure of key personnel;

•the economy as a whole and market conditions in our industry;

•trading activity by a limited number of stockholders who together beneficially own a majority of our outstanding common stock;

•the size of our market float; and

•any other factors discussed in this report.

In addition, the stock markets have experienced extreme price and volume fluctuations that have affected and continue to affect the market prices of equity securities of many immuno-oncology companies. Stock prices of many immuno-oncology companies have fluctuated in a manner unrelated or disproportionate to the operating performance of those companies. In the past, stockholders have filed securities class action litigation following periods of market volatility. If we were to become involved in securities litigation, it could subject us to substantial costs, divert resources and the attention of management from our business and adversely affect our business.

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The amount of our future losses is uncertain and our quarterly operating results may fluctuate significantly or may fall below the expectations of investors or securities analysts, each of which may cause our stock price to fluctuate or decline.

Our quarterly and annual operating results may fluctuate significantly in the future due to a variety of factors, many of which are outside of our control and may be difficult to predict, including the following:

•the timing and success or failure of clinical trials for our investigational products or competing investigational products, or any other change in the competitive landscape of our industry, including consolidation among our competitors or partners;

•our progress towards the achievement of any product development goals or milestones we announce, including any delays or failures which lead to the suspension or termination of any clinical trial or development program;

•the timing and cost of, and level of investment in, research and development activities relating to our investigational products, which may change from time to time;

•option fees received by us in connection with option exercises by Gilead and/or Taiho pursuant to their respective option agreements and/or payments received by us from Gilead or Taiho in connection with the achievement of certain development and/or regulatory milestones;

•amounts payable by us in connection with the achievement of development, regulatory and commercial milestones under our in-license and other strategic agreements;

•our ability to attract, hire and retain qualified personnel;

•expenditures that we will or may incur to develop additional investigational products;

•our ability to obtain marketing approval for our investigational products, and the timing and scope of any such approvals we may receive;

•the changing and volatile U.S. and global economic environments; and

•future accounting pronouncements or changes in our accounting policies.

The cumulative effects 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. 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 guidance we may provide.

The concentration of our stock ownership will likely limit our stockholders’ ability to influence corporate matters, including the ability to influence the outcome of director elections and other matters requiring stockholder approval.

Based upon shares outstanding as of September 30, 2023, our executive officers, directors and the holders of more than 5% of our outstanding common stock, in the aggregate, beneficially owned approximately 47.6% of our common stock. In particular, Gilead owns approximately 19.8% of our outstanding common stock (and has the right to acquire additional shares of our common stock from us to enable it to own up to 35% of our outstanding common stock), and we have appointed its two designees to our board of directors pursuant to the terms of the Investor Rights Agreement. As a result, these stockholders, acting together, will have significant influence over all matters that require approval by our stockholders, including the election of directors and approval of significant corporate transactions. Corporate actions might be taken even if other stockholders oppose them. This concentration of ownership might also have the effect of delaying or preventing a change of control of our company that other stockholders may view as beneficial.

55

Delaware law and provisions in our amended and restated certificate of incorporation and amended and restated bylaws could make a merger, tender offer or proxy contest difficult, thereby depressing the trading price of our common stock.

Our status as a Delaware corporation and the anti-takeover provisions of the Delaware General Corporation Law may discourage, delay or prevent a change in control by prohibiting us from engaging in a business combination with an interested stockholder for a period of three years after the person becomes an interested stockholder, even if a change of control would be beneficial to our existing stockholders. In addition, our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that may make the acquisition of our company more difficult, including the following:

•a classified board of directors with three-year staggered terms, which could delay the ability of stockholders to change the membership of a majority of our board of directors;

•the ability of our board of directors to issue shares of preferred stock and to determine the price and other terms of those shares, including preferences and voting rights, without stockholder approval, which could be used to significantly dilute the ownership of a hostile acquirer;

•the exclusive right of our board of directors to elect a director to fill a vacancy created by the expansion of our board of directors or the resignation, death or removal of a director, which prevents stockholders from being able to fill vacancies on our board of directors;

•a prohibition on stockholder action by written consent, which forces stockholder action to be taken at an annual or special meeting of our stockholders;

•the requirement that a special meeting of stockholders may be called only by a majority vote of our entire board of directors, the chairman of our board of directors or our chief executive officer, which could delay the ability of our stockholders to force consideration of a proposal or to take action, including the removal of directors;

•the requirement for the affirmative vote of holders of at least 66 2⁄3% of the voting power of all of the then-outstanding shares of the voting stock, voting together as a single class, to amend the provisions of our amended and restated certificate of incorporation relating to the management of our business or our amended and restated bylaws, which may inhibit the ability of an acquirer to effect such amendments to facilitate an unsolicited takeover attempt; and

•advance notice procedures with which stockholders must comply to nominate candidates to our board of directors or to propose matters to be acted upon at a stockholders’ meeting, which may discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of us.

In addition, as a Delaware corporation, we are subject to Section 203 of the Delaware General Corporation Law. These provisions may prohibit large stockholders, in particular those owning 15% or more of our outstanding voting stock, from merging or combining with us for a certain period of time. A Delaware corporation may opt out of this provision by express provision in its original certificate of incorporation or by amendment to its certificate of incorporation or bylaws approved by its stockholders. However, we have not opted out of this provision.

These and other provisions in our amended and restated certificate of incorporation, amended and restated bylaws and Delaware law 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 our then-current board of directors, including delay or impede a merger, tender offer or proxy contest involving our company. The existence of these provisions could negatively affect the price of our common stock and limit opportunities for our stockholders to realize value in a corporate transaction.

Our amended and restated certificate of incorporation provides that the Court of Chancery of the State of Delaware is the exclusive forum for substantially all disputes between us and our stockholders, which could limit our stockholders’ ability to obtain a favorable judicial forum for disputes with us or our directors, officers or employees.

Our amended and restated certificate of incorporation and our bylaws provide that the Court of Chancery of the State of Delaware is the exclusive forum for any derivative action or proceeding brought on our behalf, any action asserting a breach of fiduciary duty, any action asserting a claim against us arising pursuant to the Delaware General Corporation Law, our certificate of incorporation or our bylaws or any action asserting a claim against us that is governed by the internal affairs doctrine. In addition, to prevent having to litigate claims in multiple jurisdictions and the threat of inconsistent or contrary rulings by different courts, among other considerations, our bylaws provide that the federal district courts of the United States will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act of 1933, as amended. These choice of forum provisions may limit a stockholder’s ability to bring a claim

56

in a judicial forum that it finds favorable for disputes with us or our directors, officers or other employees and may discourage these types of lawsuits. While the Delaware courts have determined that these types of forum provisions are facially valid, a stockholder may nevertheless seek to bring a claim in a venue other than those designated in the exclusive forum provisions. In such instance, we would expect to vigorously assert the validity and enforceability of these provisions, which may require significant additional costs associated with resolving such action in other jurisdictions, and there can be no assurance that the provisions will be enforced by a court in those other jurisdictions.

General Risk Factors

Sales of substantial amounts of our shares may cause the price of our common stock to decline.

The price of our common stock could decline if there are substantial sales of our common stock, including any sales by us, our directors, executive officers, significant stockholders or the sales agents under the equity distribution agreement, or if there is a large number of shares of our common stock available for sale and the market perceives that sales will occur. We have also registered shares of common stock that we have issued and may issue under our employee equity incentive plans. These shares can be sold freely in the public market upon issuance, subject to vesting conditions and, in the case of our affiliates, volume limitations under Rule 144 under the Securities Act of 1933, as amended.

If we fail to maintain proper and effective internal controls, our ability to produce accurate and timely financial statements could be impaired, which could result in sanctions or other penalties that would harm our business.

We are subject to the reporting requirements of the Exchange Act, the Sarbanes-Oxley Act and the rules and regulations of the New York Stock Exchange. The Sarbanes-Oxley Act requires, among other things, that we maintain effective disclosure controls and procedures and internal controls over financial reporting.

Our internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements in accordance with generally accepted accounting principles. Our internal control over financial reporting will not prevent or detect all errors and all fraud. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud will be detected. Accordingly, we cannot assure you that we will not in the future identify one or more material weaknesses in our internal control over financial reporting, which may have a negative impact on our ability to timely and accurately produce financial statements, may result in a material misstatement of our Consolidated Financial Statements or may negatively impact the confidence level of our stockholders and other market participants with respect to our reported financial information.

Ensuring that we have adequate internal controls over financial reporting is a costly and time-consuming effort that needs to be re-evaluated frequently. Recent trends in remote work arrangements have led to changes in work patterns that can make it more difficult to properly perform our controls and may create risks that result in deficiencies in the design of our controls. To the extent necessary, implementing any changes to our internal controls may distract our officers and employees, entail substantial costs to modify our existing processes and take significant time to complete. These changes may not, however, be effective in maintaining the adequacy of our internal controls, and any failure to maintain that adequacy, or consequent inability to produce accurate financial statements on a timely basis, could increase our operating costs and harm our business.

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

None.

Item 3. Defaults Upon Senior Securities.

None.

Item 4. Mine Safety Disclosures.

None.

57

Item 5. Other Information.

Rule 10b5-1 Trading Arrangements

The adoption, modification or termination of contracts, instructions or written plans for the purchase or sale of our securities by our Section 16 officers and directors for the three months ended September 30, 2023, which are intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act, were as follows:

Name and Title	Action	Date	Total Shares to be Sold	Expiration Date
Juan C. Jaen President and Director	Adopted	August 8, 2023	300,000	November 8, 2024

58

Item 6. Exhibits.

The documents listed below are incorporated by reference or are filed with this Quarterly Report on Form 10-Q, in each case as indicated therein (numbered in accordance with Item 601 of Regulation S-K).

Exhibit Number		Incorporated by Reference
	Exhibit Description	Form	File No.	Exhibit	Filing Date
3.1	Amended and Restated Certificate of Incorporation	10-Q	001-38419	3.1	May 9, 2018
3.2	Amended and Restated Bylaws	8-K	001-38419	3.1	May 26, 2020
10.1A*	Memorandum, dated July 27, 2023, between Arcus Biosciences, Inc. and Taiho Pharmaceutical Co., LTD.
31.1*	Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2*	Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as 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	XBRL Instance Document – The instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCH	Inline XBRL Taxonomy Extension Schema Document
101.CAL	Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF	Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB	Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE	Inline XBRL Taxonomy Extension Presentation Linkbase Document
104	Cover Page Interactive Data File (formatted as inline XBRL and contained in exhibit 101)

_____________________________________

*Filed herewith.

†This certification is deemed furnished but not filed for purposes of section 18 of the Exchange Act, or otherwise subject to the liability of that section, nor shall it be deemed incorporated by reference into any filing under the Securities Act or the Exchange Act.

AThis exhibit omits certain information the Company deems immaterial and of the type that it treats as confidential.

59

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.

		ARCUS BIOSCIENCES, INC.
Date:	November 7, 2023	By:	/s/ Terry Rosen
			Terry Rosen, Ph.D.
			Chief Executive Officer (Principal Executive Officer)
Date:	November 7, 2023	By:	/s/ Alexander Azoy
			Alexander Azoy
			Chief Accounting Officer (Principal Accounting Officer)

60

EX-10.1

Exhibit 10.1

[***] = INFORMATION HAS BEEN OMITTED BECAUSE IT IS BOTH NOT MATERIAL AND IS THE TYPE OF INFORMATION THAT ARCUS BIOSCIENCES, INC. TREATS AS PRIVATE OR CONFIDENTIAL

MEMORANDUM

This memorandum (this “Memorandum”) is made and entered into effective as of July 27, 2023 (the “Effective Date”) by and between Arcus Biosciences, Inc., a company organized under the laws of State of Delaware, U.S.A., having a business address at 3928 Point Eden Way, Hayward, CA 94545, U.S.A. (“Arcus”), and TAIHO Pharmaceutical Co., Ltd., a corporation organized under the laws of Japan, having a business address at 1-27 Kandanishiki-cho, Chiyoda-ku, Tokyo 101-8444, Japan (“TAIHO”). Arcus and TAIHO are sometimes collectively referred to herein as the “Parties” and separately as a “Party.” Capitalized terms used herein but not defined herein shall have the meaning set forth in that certain Option and LicenseAgreement made and entered into effective as of September 19, 2017,by and between Arcusand TAIHO,as amended September 1, 2018 and as may be further amended from time to time(the “Agreement”).

Whereas, pursuant to the Agreement, Arcus granted to TAIHO, with respect to each Arcus Program, (a) during the Exercise Period for such Arcus Program, an exclusive option to obtain an exclusive license to Develop and Commercialize the Option Products in such Arcus Program in the Field in and for the Territory and (b) upon TAIHO’s exercise of the Option, an exclusive license to Develop and Commercialize Licensed Products in the Field in and for the Territory during the Term.

Whereas, TAIHO exercised its Option with respect to that certain Arcus Program, Antibodies to PD-1, including but not limited to AB122 (“PD-1 Program”) and that certain Arcus Program, Antibodies to TIGIT, including but not limited to AB154 (“TIGIT Program”), and obtained the License with respect thereto.

Whereas, the Parties now desire to clarify certain matters with respect to the Development and Regulatory Milestones of PD-1 Program and TIGIT Program, as set forth below.

Now, Therefore, in consideration of the mutual covenants, agreements and stipulations set forth herein, the receipt and legal sufficiency of which are hereby mutually acknowledged, the Parties hereby agree as follows:

ARTICLE I

SKIPPED MILESTONES

TAIHO is joining two Phase III Clinical Trials the titles of which are “A Randomized, Open-Label, Multicenter Phase 3 Trial of Domvanalimab, Zimberelimab, and Chemotherapy Versus Nivolumab and Chemotherapy in Participants with Previously-Untreated Locally Advanced Unresectable or Metastatic Gastric, Gastroesophageal Junction, and Esophageal Adenocarcinoma” (the “STAR-221 Study”) and “A Randomized, Open-Label, Phase 3 Study to Evaluate Zimberelimab and Domvanalimab in Combination With Chemotherapy Versus Pembrolizumab With Chemotherapy for the First-Line Treatment of Patients With Metastatic Non-Small Cell Lung Cancer With No Epidermal Growth Factor Receptor or Anaplastic Lymphoma Kinase Genomic Tumor Aberrations” (the “STAR-121 Study”), both of which are Global Studies and also Phase III Clinical Trials to ascertain efficacy and safety of combination therapy of AB122 and AB154. Arcus and TAIHO acknowledge and agree that, pursuant to Section 5.2(d)(iii) of the Agreement, milestone 1 of the Global Study Pathway for [***] will be deemed to have been met upon [***], respectively, for each of the PD-1 Program and the TIGIT Program and such milestone amounts payable by Taiho to Arcus in accordance with Section 5.2(d)(iii) of the Agreement.

1

CONFIDENTIAL

ARTICLE II

INITIATION OF THE FIRST PHASE III STUDY WITH RESPECT TO PD-1 PROGRAM AND TIGIT PROGRAM

In the protocol of the STAR-221 Study in Japan, [***]. Given the purpose of the [***] as above, Arcus and TAIHO acknowledge and agree that, with respect to the Development and Regulatory Milestones corresponding to the STAR-221 Study, the timing of milestone 2 [***] under Section 5.2(a) of the Agreement, shall be [***].

ARTICLE III

DEVELOPMENT AND REGULATORY MILESTONE PAYMENT

WITH RESPECT TO PD-1 PROGRAM AND TIGIT PROGRAM

The Parties hereby agree that solely for the first Development and Regulatory Milestone paid by Taiho to Arcus for the PD-1 Program and TIGIT Program pursuant to Section 5.2(a) of the Agreement, Taiho may [***].

ARTICLE IV
GENERAL

4.1    No Modifications. Except as specifically set forth in this Memorandum, the terms and conditions of the Agreement shall remain in full force and effect. No waiver, alteration or modification of any of the provisions of this Memorandum shall be binding unless made in writing and signed by the Parties by their respective officers thereunto duly authorized. The waiver by either Party of a breach or a default of any provision of this Memorandum by the other Party shall not be construed as a waiver of any succeeding breach of the same or any other provision, nor shall any delay or omission on the part of either Party to exercise or avail itself of any right, power or privilege that it has or may have hereunder operate as a waiver of any right, power or privilege by such Party.

4.2    Miscellaneous. This Memorandum may be executed in any number of counterparts, each of which shall be deemed an original but all of which together shall constitute one and the same instrument. This Memorandum, once executed by a Party may be delivered via electronic means of transmission and shall have the same force and effect as if it were executed and delivered by the Parties in the presence of one another. This Memorandum shall be governed by and construed in accordance with the laws of theState of California, United States without regard to its conflicts of laws principles.

[Remainder of Page Intentionally Left Blank]

1

CONFIDENTIAL

IN WITNESS WHEREOF, the Parties hereto have caused this Memorandum to be executed as of the Effective Date by their duly authorized representatives.

Arcus Biosciences, Inc.

By:      /s/ Terry Rosen                

Name:     Terry Rosen                    

Title:     CEO                        

Date:      7/27/2023                    

TAIHO Pharmaceutical Co., Ltd.

By:      /s/ Atsushi Azuma                

Name:     Atsushi Azuma                

Title:     Managing Director, Board Member, Business    

Development                    

Date:      8/1/2023                    

    -2-

EX-31.1

Exhibit 31.1

CERTIFICATION PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES EXCHANGE ACT OF 1934,

AS ADOPTED PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Terry Rosen, certify that:

1.I have reviewed this Form 10-Q of Arcus Biosciences, 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 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 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 7, 2023	By:	/s/ Terry Rosen
		Terry Rosen, Ph.D.
		Chief Executive Officer (Principal Executive Officer)

EX-31.2

Exhibit 31.2

CERTIFICATION PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES EXCHANGE ACT OF 1934,

AS ADOPTED PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Robert C. Goeltz II, certify that:

1.I have reviewed this Form 10-Q of Arcus Biosciences, 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 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 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 7, 2023	By:	/s/ Robert C. Goeltz II
		Robert C. Goeltz II
		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 of Arcus Biosciences, Inc. (the “Company”) on Form 10-Q for the period ending September 30, 2023 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that to the best of my 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 result of operations of the Company.

Date: November 7, 2023	By:	/s/ Terry Rosen
		Terry Rosen, Ph.D.
		Chief Executive Officer (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 of Arcus Biosciences, Inc. (the “Company”) on Form 10-Q for the period ending September 30, 2023 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that to the best of my 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 result of operations of the Company.

Date: November 7, 2023	By:	/s/ Robert C. Goeltz II
		Robert C. Goeltz II
		Chief Financial Officer (Principal Financial Officer)

XML

Cover - shares	9 Months Ended
	Sep. 30, 2023	Nov. 01, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-38419
Entity Registrant Name	Arcus Biosciences, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-3898435
Entity Address, Address Line One	3928 Point Eden Way
Entity Address, City or Town	Hayward
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94545
City Area Code	510
Local Phone Number	694-6200
Title of 12(b) Security	Common Stock, Par Value $0.0001 Per Share
Trading Symbol	RCUS
Security Exchange Name	NYSE
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		74,855,565
Entity Central Index Key	0001724521
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3

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Condensed Consolidated Statements of Operations - USD ($) shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues:
Total revenues	$ 32,000,000	$ 33,000,000	$ 86,000,000	$ 78,000,000
Operating expenses:
Research and development (Net of recoveries of $22, $27, $89 and $93 from a related party)	82,000,000	77,000,000	247,000,000	208,000,000
General and administrative	30,000,000	26,000,000	88,000,000	76,000,000
Total operating expenses	112,000,000	103,000,000	335,000,000	284,000,000
Loss from operations	(80,000,000)	(70,000,000)	(249,000,000)	(206,000,000)
Non-operating income (expense):
Interest and other income, net	12,000,000	5,000,000	30,000,000	8,000,000
Effective interest on liability for sale of future royalties	(1,000,000)	0	(2,000,000)	(1,000,000)
Total non-operating income, net	11,000,000	5,000,000	28,000,000	7,000,000
Loss before income taxes	(69,000,000)	(65,000,000)	(221,000,000)	(199,000,000)
Income tax expense	(2,000,000)	0	(5,000,000)	(1,000,000)
Net loss	$ (71,000,000)	$ (65,000,000)	$ (226,000,000)	$ (200,000,000)
Net loss per share, basic (in dollars per share)	$ (0.94)	$ (0.90)	$ (3.07)	$ (2.78)
Net loss per share, diluted (in dollars per share)	$ (0.94)	$ (0.90)	$ (3.07)	$ (2.78)
Shares used to compute net loss per share, basic (in shares)	74.6	72.2	73.6	71.8
Shares used to compute net loss per share, diluted (in shares)	74.6	72.2	73.6	71.8
License and Development Services Revenue
Revenues:
Total revenues	$ 22,000,000	$ 23,000,000	$ 58,000,000	$ 48,000,000
Other Collaboration Revenue
Revenues:
Total revenues	$ 10,000,000	$ 10,000,000	$ 28,000,000	$ 30,000,000

XML

Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue from contract with customer, excluding assessed tax	$ 32	$ 33	$ 86	$ 78
Related Party
Research and development expense, net of recoveries	22	27	89	93
License and Development Services Revenue
Revenue from contract with customer, excluding assessed tax	22	23	58	48
License and Development Services Revenue | Related Party
Revenue from contract with customer, excluding assessed tax	18	23	54	48
Other Collaboration Revenue
Revenue from contract with customer, excluding assessed tax	10	10	28	30
Other Collaboration Revenue | Related Party
Revenue from contract with customer, excluding assessed tax	$ 10	$ 8	$ 28	$ 25

XML

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Net loss	$ (71)	$ (65)	$ (226)	$ (200)
Other comprehensive income (loss)	1	(2)	4	(8)
Comprehensive loss	$ (70)	$ (67)	$ (222)	$ (208)

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Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 184	$ 206
Marketable securities	615	803
Receivable from collaboration partners ($22 and $39 from a related party)	52	39
Prepaid expenses and other current assets	31	19
Total current assets	882	1,067
Long-term marketable securities	151	129
Property and equipment, net	50	35
Other noncurrent assets ($6 and $2 from a related party)	108	114
Total assets	1,191	1,345
Current liabilities:
Accounts payable	17	20
Deferred revenue ($96 and $97 to a related party)	103	97
Other current liabilities	80	76
Total current liabilities	200	193
Deferred revenue, noncurrent ($309 and $355 to a related party)	326	355
Other noncurrent liabilities	145	140
Commitments
Stockholders’ equity:
Preferred stock, $0.0001 par value per share; 10.0 shares authorized; no shares issued and outstanding.	0	0
Common stock and additional paid-in capital: $0.0001 par value per share; 400.0 shares authorized; 74.8 shares in 2023 and 72.9 shares in 2022 issued and outstanding	1,291	1,206
Accumulated deficit	(768)	(542)
Accumulated other comprehensive loss	(3)	(7)
Total stockholders’ equity	520	657
Total liabilities and stockholders’ equity	$ 1,191	$ 1,345

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Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Receivable from collaboration partners, current	$ 52	$ 39
Other noncurrent assets	108	114
Deferred revenue, current	103	97
Deferred revenue, noncurrent	$ 326	$ 355
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	10,000,000.0	10,000,000.0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	400,000,000.0	400,000,000.0
Common stock, shares issued (in shares)	74,800,000	72,900,000
Common stock, shares outstanding (in shares)	74,800,000	72,900,000
Related Party
Receivable from collaboration partners, current	$ 22	$ 39
Other noncurrent assets	6	2
Deferred revenue, current	96	97
Deferred revenue, noncurrent	$ 309	$ 355

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Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Second Stock Purchase Agreement Gilead	Equity Award Programs	Common Stock	Common Stock Second Stock Purchase Agreement Gilead	Common Stock Equity Award Programs	Common stock and additional paid-in capital	Common stock and additional paid-in capital Second Stock Purchase Agreement Gilead	Common stock and additional paid-in capital Equity Award Programs	Accumulated deficit	Accumulated other comprehensive loss
Beginning balance, shares at Dec. 31, 2021				70.8
Beginning balance at Dec. 31, 2021	$ 842						$ 1,118			$ (275)	$ (1)
Issuance of common stock (in shares)						0.8
Issuance of common stock			$ 10						$ 10
Stock-based compensation	17						17
Other comprehensive gain (loss)	(4)										(4)
Net loss	(68)									(68)
Ending balance, shares at Mar. 31, 2022				71.6
Ending balance at Mar. 31, 2022	797						1,145			(343)	(5)
Beginning balance, shares at Dec. 31, 2021				70.8
Beginning balance at Dec. 31, 2021	842						1,118			(275)	(1)
Net loss	(200)
Ending balance, shares at Sep. 30, 2022				72.4
Ending balance at Sep. 30, 2022	699						1,183			(475)	(9)
Beginning balance, shares at Mar. 31, 2022				71.6
Beginning balance at Mar. 31, 2022	797						1,145			(343)	(5)
Issuance of common stock (in shares)						0.5
Issuance of common stock			4						4
Stock-based compensation	15						15
Other comprehensive gain (loss)	(2)										(2)
Net loss	(67)									(67)
Ending balance, shares at Jun. 30, 2022				72.1
Ending balance at Jun. 30, 2022	747						1,164			(410)	(7)
Issuance of common stock (in shares)						0.3
Issuance of common stock			3						3
Stock-based compensation	16						16
Other comprehensive gain (loss)	(2)										(2)
Net loss	(65)									(65)
Ending balance, shares at Sep. 30, 2022				72.4
Ending balance at Sep. 30, 2022	$ 699						1,183			(475)	(9)
Beginning balance, shares at Dec. 31, 2022	72.9			72.9
Beginning balance at Dec. 31, 2022	$ 657						1,206			(542)	(7)
Issuance of common stock (in shares)						0.2
Issuance of common stock			1						1
Stock-based compensation	19						19
Other comprehensive gain (loss)	3										3
Net loss	(80)									(80)
Ending balance, shares at Mar. 31, 2023				73.1
Ending balance at Mar. 31, 2023	$ 600						1,226			(622)	(4)
Beginning balance, shares at Dec. 31, 2022	72.9			72.9
Beginning balance at Dec. 31, 2022	$ 657						1,206			(542)	(7)
Net loss	$ (226)
Ending balance, shares at Sep. 30, 2023	74.8			74.8
Ending balance at Sep. 30, 2023	$ 520						1,291			(768)	(3)
Beginning balance, shares at Mar. 31, 2023				73.1
Beginning balance at Mar. 31, 2023	600						1,226			(622)	(4)
Issuance of common stock (in shares)					1.0	0.4
Issuance of common stock		$ 20	3					$ 20	3
Stock-based compensation	18						18
Net loss	(75)									(75)
Ending balance, shares at Jun. 30, 2023				74.5
Ending balance at Jun. 30, 2023	566						1,267			(697)	(4)
Issuance of common stock (in shares)				0.2		0.1
Issuance of common stock	5		$ 1				5		$ 1
Stock-based compensation	18						18
Other comprehensive gain (loss)	1										1
Net loss	$ (71)									(71)
Ending balance, shares at Sep. 30, 2023	74.8			74.8
Ending balance at Sep. 30, 2023	$ 520						$ 1,291			$ (768)	$ (3)

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Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net loss	$ (226)	$ (200)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Stock-based compensation expense	55	48
Depreciation and amortization	5	5
Noncash lease expense	6	6
Amortization of premiums (discounts) on marketable securities	(13)	2
Other items, net	2	3
Changes in operating assets and liabilities:
Receivable from collaboration partners ($17 and $718 from a related party)	15	716
Other assets (($4) and ($2) from a related party)	(12)	(4)
Accounts payable	(3)	0
Deferred revenue (($47) and ($73) to a related party)	(51)	(78)
Other liabilities	4	10
Net cash provided by (used in) operating activities	(218)	508
Cash flows from investing activities
Purchases of marketable securities	(673)	(1,085)
Proceeds from maturities of marketable securities	837	491
Proceeds from sales of marketable securities	20	143
Purchases of property and equipment	(18)	(6)
Purchases of in-process research and development	0	(6)
Collaboration reimbursements of in-process research and development	0	3
Net cash provided by (used in) investing activities	166	(460)
Cash flows from financing activities
Proceeds from issuance of common stock ($20 and $— from a related party)	25	0
Proceeds from issuance of common stock pursuant to equity award plans	5	17
Proceeds from sale of future royalties	0	5
Net cash provided by financing activities	30	22
Net increase (decrease) in cash, cash equivalents and restricted cash	(22)	70
Cash, cash equivalents and restricted cash at beginning of period	209	151
Cash, cash equivalents and restricted cash at end of period	187	221
Non-cash investing and financing activities:
Unpaid portion of property and equipment purchases included in Accounts payable and Other current liabilities	$ 6	$ 1

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Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Receivable from collaboration partners	$ 15	$ 716
Other assets	(12)	(4)
Deferred revenue	(51)	(78)
Proceeds from issuance of common stock	25	0
Related Party
Receivable from collaboration partners	17	718
Other assets	4	2
Deferred revenue	(47)	(73)
Proceeds from issuance of common stock	$ 20	$ 0

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Organization, Liquidity, and Capital Resources

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization, Liquidity, and Capital Resources

Organization, liquidity and capital resources

Organization

Arcus Biosciences, Inc. (referred to as "Arcus," "we," "our," "us," or the "Company") is a clinical-stage, biopharmaceutical company focused on creating best-in-class therapies. Using our robust and highly efficient drug discovery capability, we have created a significant portfolio of investigational products which are in clinical development, with our most advanced molecule, an anti-TIGIT antibody, now in four Phase 3 registrational studies targeting lung and gastrointestinal cancers. Our deep portfolio of novel small molecules and enabling antibodies allows us to create highly differentiated therapies, which we are developing to treat multiple large indications.

We operate and manage our business as one reportable and operating segment, which is the business of developing and commercializing highly differentiated therapies that have a meaningful impact on patients.

Liquidity and Capital Resources

As of September 30, 2023, we had cash, cash equivalents and marketable securities of $950 million, which we believe will be sufficient to fund our planned operations for a period of at least twelve months following the date of filing of this report.

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Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Summary of significant accounting policies

Basis of Presentation

These interim financial statements should be read in conjunction with the audited Consolidated Financial Statements and the related notes thereto for the year ended December 31, 2022 included in our Annual Report on Form 10-K filed with the SEC on February 28, 2023. There have been no significant changes to our accounting policies as described in Note 2, Summary of significant accounting policies, in the notes to Consolidated Financial Statements in Item 8 of Part II of the Form 10-K.

These interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and include all adjustments consisting of normal recurring adjustments that management believes are necessary for a fair presentation of the periods presented. The Condensed Consolidated Balance Sheet as of December 31, 2022 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements.

Operating results for the nine months ended September 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023 or for any future period.

Use of Estimates

The preparation of the Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and related disclosures. We base our estimates on historical experience and on various market-specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Estimates are assessed and updated each period to reflect current information. Actual results may differ materially from those estimates.

Recent Accounting Pronouncements

There have been no new accounting pronouncements issued or adopted during the period with a significant impact to our financial statements.

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Related Party - Gilead Sciences, Inc.

9 Months Ended

Sep. 30, 2023

Related Party Transactions [Abstract]

Related Party - Gilead Sciences, Inc.

Related party - Gilead Sciences, Inc.

In 2020, we and Gilead Sciences, Inc. (Gilead) entered into an Option, License and Collaboration Agreement (the Gilead Collaboration Agreement), Common Stock Purchase Agreement (the Stock Purchase Agreement), and Investor Rights Agreement (Investor Rights Agreement). In 2021, we amended the Gilead Collaboration Agreement (the First Gilead Collaboration Agreement Amendment) and the Stock Purchase Agreement (the First Stock Purchase Agreement Amendment), and in 2022 we amended the Investor Rights Agreement (Amended Investor Rights Agreement). In the second quarter of 2023, we expanded our collaboration to include research-stage inflammation programs (the Second Gilead Collaboration Agreement Amendment) and further amended the Stock Purchase Agreement (the Second Stock Purchase Agreement Amendment). We refer to these agreements collectively as the Gilead Agreements.

Stock Purchase Agreement and Investor Rights Agreement

In 2020, under the Stock Purchase Agreement, Gilead purchased 6.0 million shares of our common stock for a total cost of $200 million, of which $91 million was allocated to the revenue related performance obligations created by the Gilead Collaboration Agreement (See Note 5, Revenues for more information).

In 2021, under the First Stock Purchase Agreement Amendment, Gilead purchased 5.7 million shares of our common stock for a total cost of $220 million.

In June 2023, under the Second Stock Purchase Agreement Amendment, Gilead purchased 1.0 million shares of our common stock for a total cost of $20 million.

Gilead has the right, at its option until July 2025, to purchase up to a maximum of 35% of the Company’s then-outstanding voting common stock, at a purchase price equal to the greater of a 20% premium to market (based on a trailing five-day average closing price at option exercise) or the $33.54 initial purchase price. Based on the value of our common stock at each contract closing, the right to purchase additional shares had no value.

Under the Investor Rights Agreement, Gilead has the right, which they have exercised, to designate two members of our Board of Directors. This agreement also included a three-year standstill and a two-year lockup, provided Gilead with registration rights commencing at the end of the lockup period and provides Gilead with pro rata participation rights in certain future financings. In October 2022, we registered Gilead’s shares and entered into the Amended Investor Rights Agreement, primarily to extend the two-year lockup period to three-years which expired on July 13, 2023.

As of September 30, 2023, Gilead held approximately 19.8% of the Company’s outstanding common stock arising from purchases in our May 2020 public offering and purchases under the Stock Purchase Agreement and the First and Second Amended Stock Purchase Agreements.

Collaboration Agreements

In 2020, we entered into the Gilead Collaboration Agreement, which gave Gilead an exclusive license to develop and commercialize zimberelimab (the anti PD-1 program) in certain markets and time-limited options to acquire exclusive licenses to develop and commercialize any of our then-current and future clinical programs arising during the 10-year collaboration term, contingent upon $100 million option continuation payments payable on each of the second, fourth, sixth and eighth anniversaries of the agreement. Upon closing of the transaction in July 2020, Gilead made an upfront payment of $175 million.

In 2021, we entered into the First Gilead Collaboration Agreement Amendment pursuant to which Gilead exercised its option to three programs—providing Gilead with exclusive licenses to develop and commercialize domvanalimab and AB308 (collectively, the anti-TIGIT program), etrumadenant (the adenosine receptor antagonist program) and quemliclustat (the CD73 program), in certain markets—for a total payment of $725 million that was received in 2022. The amendment also (i) provided for a slight reduction in the royalties for these three programs, such that Gilead will pay us tiered royalties as a percentage of revenues ranging from the mid-teens to the low twenties; and (ii) removed the $100 million option continuation payment that was otherwise due on the second anniversary of the Gilead Collaboration Agreement.

Gilead's option, on a program-by-program basis, will expire after a prescribed period following the achievement of a clinical development milestone in such program and our delivery to Gilead of the requisite data package. Gilead may exercise its option to any program at any time prior to expiration of the option and will pay Arcus an option fee of $150 million per program. With respect to domvanalimab, we are also eligible to receive up to $500 million in potential U.S. regulatory approval milestones.

For each program that Gilead opts in to, both companies will co-develop and equally share global development costs, subject to certain opt-out rights that we have, and caps on our spending and related subsequent adjustments. For each program, provided we have not exercised our opt-out rights, we have the option to co-promote in the United States with equal sharing of related profits and losses. Gilead has the right to exclusively commercialize outside of the U.S., subject to the rights of our existing partners in any territories and will pay us tiered royalties as a percentage of revenues ranging from the high teens to the low twenties.

Under the First Gilead Collaboration Agreement Amendment, Gilead also has option rights to two immuno-oncology research programs for which we will lead discovery and early development activities. With respect to these two research programs, Gilead has the right to exercise its option, on a program-by-program basis, either (i) upon our completion of certain IND-enabling activities for an option payment of $60 million or (ii) following the achievement of a clinical development milestone for an option payment of $150 million. These research programs were not determined to be performance obligations at contract inception, due to the very early stages of the programs.

In May 2023, we entered into the Second Gilead Collaboration Agreement Amendment pursuant to which we expanded our collaboration to provide Gilead with options to license up to four jointly selected research-stage programs that target inflammatory diseases for which we will lead discovery and early development activities. We will receive an upfront payment of $17.5 million for each initiated program and Gilead will have an option to license each program at two separate, prespecified time points. For the first two research programs, Gilead has the right to exercise its option, on a program-by-program basis, either (i) upon our completion of certain IND-enabling activities for an option payment of $45 million or (ii) following the achievement of a clinical development milestone for an option payment of $150 million. If Gilead exercises its option at the earlier time point for the first two programs, we would be eligible to receive up to $375 million in regulatory and commercial milestone payments as well as tiered royalties for each optioned program. For any other program option exercise by Gilead, the parties would have rights to co-develop and share global development costs and to co-commercialize and share profits in the US for that program. We received a total upfront payment of $35 million for an initial two research programs in June 2023.

As of September 30, 2023, Gilead has licenses to domvanalimab, AB308, etrumadenant, quemliclustat and zimberelimab.

For the three months ended September 30, 2023 and 2022, we recognized revenue under the Gilead Agreements of $28 million and $31 million, respectively, and net reimbursements from Gilead recognized as reductions in research and development (R&D) expense of $22 million and $27 million, respectively. For the nine months ended September 30, 2023 and 2022, we recognized revenue under the Gilead Agreements of $82 million and $73 million, respectively, and net reimbursements from Gilead recognized as reductions in R&D expense of $89 million and $93 million, respectively.

For a more detailed discussion on revenues recognized under the Gilead Agreements, see Note 5, Revenues.

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License and Collaborations

9 Months Ended

Sep. 30, 2023

License and Collaboration Agreements [Abstract]

License and Collaborations

License and collaborations

We enter into licensing agreements, strategic collaborations and other similar arrangements with third parties for the development and commercialization of certain investigational products. These arrangements may be collaborative and involve two or more parties who are active participants in the operating activities of the collaboration and are exposed to significant risks and rewards depending on the commercial success of the activities. These arrangements may include: non-refundable upfront payments; payments for options to acquire certain rights; potential development and regulatory milestone payments and/or sales-based milestone payments; royalty payments; revenue or profit-sharing arrangements; expense reimbursements; and cost-sharing arrangements.

Operating expenses for costs incurred pursuant to these arrangements are reported in their respective expense line items in the Condensed Consolidated Statements of Operations, net of any payments due to or reimbursements due from our collaboration partners, with such reimbursements being recognized at the time the party becomes obligated to pay.

Our significant arrangements are discussed below.

Gilead Collaboration

See Note 3, Related party - Gilead Sciences, Inc.

Taiho Collaboration

In 2017, we entered into an agreement with Taiho Pharmaceutical Co., Ltd (Taiho) under which we granted Taiho exclusive options to programs arising over a five-year period which ended in September 2022 (the Option Period) for an upfront payment of $35 million. Upon an option exercise of a program, Taiho would obtain exclusive development and commercialization rights to investigational products under the program for Japan and certain other territories in Asia (excluding China) (the Taiho Territory).

For each option that Taiho exercises, they will be obligated to make a payment of $3 million to $15 million, depending on the development stage of the optioned program. Upon exercise, Taiho is solely responsible for continued development and commercialization in the Taiho Territory. In addition, for each optioned program we would be eligible to receive clinical and regulatory milestones of up to $130 million and commercial milestone payments of up to $145 million with the achievement of certain sales thresholds in the Taiho Territory. We will also receive royalties ranging from high single-digits to mid-teens on net sales of licensed products in the Taiho Territory. Royalties will be payable by product and country commencing on the first commercial sale and ending upon the later of: (a) 10 years; and (b) expiration of the last-to-expire valid claim of our patents covering the manufacture, use or sale.

During the fourth quarter of 2022, Taiho opted to participate in two global Phase 3 trials of domvanalimab and zimberelimab combinations, STAR-121 and STAR-221, and is obligated to make certain milestone payments contingent upon successfully satisfying the related clinical milestones. During the three months ended September 30, 2023, the clinical milestones for domvanalimab and zimberelimab for the STAR-221 study were met and Taiho became obligated to pay us $28 million.

As of September 30, 2023, Taiho has licenses for the Taiho Territory to (i) etrumadenant (the adenosine receptor antagonist program); (ii) zimberelimab (the anti PD-1 program); and (iii) domvanalimab and AB308 (collectively, the anti-TIGIT program).

For the three months ended September 30, 2023 and 2022, we recognized revenue of $4 million and $2 million, respectively, and we recognized net reimbursements from Taiho as a reduction in R&D expense of $2 million for the three months ended September 30, 2023. For the nine months ended September 30, 2023 and 2022, we recognized revenue of $4 million and $5 million, respectively and we recognized net reimbursements from Taiho as a reduction in R&D expense of $4 million for the nine months ended September 30, 2023. For a more detailed discussion on revenues see Note 5, Revenues.

AstraZeneca Collaboration

In 2020, we entered into a collaboration with AstraZeneca to evaluate domvanalimab, our investigational anti-TIGIT antibody, in combination with AstraZeneca’s durvalumab in a registrational Phase 3 clinical trial in patients with unresectable Stage 3 non-small cell lung cancer (NSCLC), known as the PACIFIC-8 trial. Under the collaboration, each company will retain existing rights to their respective molecules and any future commercial economics. AstraZeneca will conduct the trial, and each company will supply their respective investigational product to support the trial. Under the terms of the agreement, we will reimburse AstraZeneca for its share of the trial costs upon the achievement of certain milestones or under certain circumstances if the agreement is terminated early. The portion of the costs that we consider to be unavoidable are accrued in advance of the achievement of the milestone.

For the three months ended September 30, 2023 and 2022, we recognized as R&D expense $1 million and $1 million, respectively, before expected recoveries from our cost-sharing agreement with Gilead. For the nine months ended September 30, 2023 and 2022, we recognized as R&D expense $6 million and $3 million, respectively, before expected recoveries from our cost-sharing agreement with Gilead. At September 30, 2023 and December 31, 2022, we have recognized a liability of $11 million and $5 million, respectively, related to our obligation to AstraZeneca which is recorded in Other noncurrent liabilities.

The PACIFIC-8 trial forms part of the Arcus and Gilead joint development program for domvanalimab and our portion of the trial costs are shared with Gilead. At September 30, 2023 and December 31, 2022, we have recognized a receivable due from Gilead for these shared costs of $6 million and $2 million, respectively, which is recorded in Other noncurrent assets.

WuXi Biologics License - anti-PD-1

In 2017, we entered into an agreement with WuXi Biologics Ireland Limited (WuXi Biologics) which, as amended, provides us with exclusive rights to (i) develop, use and manufacture products that include an anti-PD-1 antibody, including zimberelimab, worldwide and (ii) commercialize any such products worldwide, except in Greater China. Under the agreement, as of September 30, 2023, we may incur (i) clinical and regulatory milestone payments, and commercialization milestone payments of up to $375 million, (ii) tiered royalties that range from the high single-digits to low teens on net sales of the licensed products and (iii) fees related to any sublicenses.

For the three and nine months ended September 30, 2023 and 2022, we did not have any transactions nor were any amounts due under this arrangement.

WuXi Biologics License - anti-CD39

In 2020, we entered into an agreement with WuXi Biologics, under which we obtained the exclusive worldwide license to develop and commercialize anti-CD39 antibodies discovered under the agreement. As of September 30, 2023, we may incur additional clinical and regulatory milestone payments of up to $14 million and royalty payments in the low single digits on net sales of the licensed products under this agreement.

For the three months ended September 30, 2023 and 2022, we incurred no development milestones nor were any amounts due under this arrangement. For the nine months ended September 30, 2023 and 2022, we incurred development milestones under this arrangement of $1 million and $2 million, respectively, which were recognized as R&D expense.

Abmuno License

In 2016, we entered into an agreement with Abmuno Therapeutics LLC (Abmuno), under which we obtained the exclusive worldwide license to develop, use, manufacture, and commercialize products that include an anti-TIGIT antibody, including domvanalimab. As of September 30, 2023 we may incur additional clinical, regulatory and commercialization milestone payments of up to $88 million under this agreement.

For the three and nine months ended September 30, 2023 and 2022, we did not have any transactions nor were any amounts due under this arrangement.

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Revenues

9 Months Ended

Sep. 30, 2023

Revenue from Contract with Customer [Abstract]

Revenues

Revenues

The following table summarizes our revenues by collaboration, category of revenue, and the method of recognition (in millions):

			Three Months Ended September 30,				Nine Months Ended September 30,
	Over time	Point in time	2023		2022		2023		2022
Gilead Collaboration
License and R&D services	*		$	20	$	23	$	57	$	48
Access rights	*		8		8		25		25
Taiho Collaboration
R&D services	*		4		—		4		—
Access rights	*		—		2		—		5
Total revenues			$	32	$	33	$	86	$	78

Revenues from Gilead accounted for 88% and 94% of Total revenues for the three months ended September 30, 2023 and 2022, respectively and 95% and 94% for the nine months ended September 30, 2023 and 2022, respectively.

The following table summarizes the revenue recognized as a result of changes in the deferred revenue balance (in millions):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue recognized from amounts included in deferred revenue at the beginning of the period	$	28	$	33	$	79	$	78

Revenue for the nine months ended September 30, 2023 includes a net $1 million cumulative catch-up of revenue due to changes in the total estimated effort to be incurred in the future to satisfy the Gilead license and R&D services performance obligations, primarily related to lower estimated late-stage clinical trial costs for etrumadenant, partially offset by higher estimated late-stage clinical trial costs for quemliclustat.

We had $429 million and $452 million of deferred revenue remaining on our Condensed Consolidated Balance Sheets at September 30, 2023 and December 31, 2022, respectively, allocated between current and noncurrent based on the expected timing of future recognition.

Revenue from the Gilead Collaboration

Activity for performance obligations under this arrangement for the periods presented herein was as follows:

Inflammation Programs - R&D Services

In May 2023, we entered into the Second Gilead Collaboration Agreement Amendment pursuant to which we expanded our collaboration to provide Gilead with options to license up to four jointly selected research-stage programs that target inflammatory diseases for which we will lead discovery and early development activities (see Note 3, Related party - Gilead Sciences, Inc., for more information). In June 2023, we received a total upfront payment of $35 million for an initial two jointly selected research-stage programs. We determined that the Second Gilead Collaboration Agreement Amendment represented a separate contract and, at the amendment closing date, we allocated the transaction price of $35 million to the performance obligations created as of the date of this amendment. The following table summarizes the allocation of the transaction price to the distinct performance obligations (in millions):

Allocation to performance obligations	Distinct	Amount
Inflammation target 1	*	$	18
Inflammation target 2	*	17
Total allocated transaction price		$	35

We determined that we have separate performance obligations to perform R&D services for Gilead related to discovery and early development activities for each research program for which they have made an upfront payment. The standalone selling price of these obligations was determined using an expected cost-plus margin approach. We recognize the amounts allocated to these services as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program. The options to acquire additional licenses or services did not result in additional performance obligations because they did not provide a material right at contract inception, primarily due to the very early stages of the programs.

We recognized revenue of $2 million and $3 million for the three and nine months ended September 30, 2023, respectively, within Other collaboration revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $32 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to these performance obligations.

Etrumadenant - License and R&D Services

Under the First Gilead Collaboration Agreement Amendment, Gilead has an exclusive license and we are also obligated to perform further R&D services for Gilead related to etrumadenant. We determined that the license and R&D services were combined based on an evaluation of the delivery of the license, due to the early stage of the technology and the specialized nature of our know-how. We allocated arrangement consideration of $219 million to the combined license and R&D services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized revenue of $21 million and $3 million for the three months ended September 30, 2023 and 2022, respectively, and $39 million and $21 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $146 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation.

Quemliclustat - License and R&D Services

Under the First Gilead Collaboration Agreement Amendment, Gilead has an exclusive license and we are also obligated to perform further R&D services for Gilead related to quemliclustat. We determined that the license and R&D services were combined based on an evaluation of the delivery of the license, due to the early stage of the technology and the specialized nature of our know-how. We allocated arrangement consideration of $176 million to the combined license and R&D services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized a reversal of revenue of $4 million for the three months ended September 30, 2023 due to changes in the total estimated effort to be incurred in the future to satisfy the performance obligations, primarily related to revised clinical trial assumptions and revenue of $12 million for the three months ended September 30, 2022. We recognized revenue of $11 million and $16 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $138 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation.

Domvanalimab - R&D Services

Under the First Gilead Collaboration Agreement Amendment, we have an obligation to perform further R&D services for Gilead related to domvanalimab. We determined that these services are distinct based on an evaluation of the delivery of the related license, noting that the program was in the later stages of development and license met the criteria for being distinct from the R&D services required. We allocated arrangement consideration of $34 million to the R&D services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized revenue of $1 million for the three months ended September 30, 2023, and $3 million and $2 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $27 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation.

Zimberelimab - R&D and Commercialization Services

Under the First Gilead Collaboration Agreement Amendment, we have an obligation to perform further R&D and commercialization services for Gilead related to zimberelimab, as a monotherapy and in combination with other agents. We determined that these services are distinct based on an evaluation of the delivery of the related license, noting that the program was in the later stages of development and license met the criteria for being distinct from the R&D and commercialization services required. We allocated arrangement consideration of $11 million to the R&D and commercialization services performance obligation and recognize the amounts allocated as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the program.

We recognized no revenue for the three months ended September 30, 2023 and $8 million for the three months ended September 30, 2022. We recognized $1 million and $9 million for the nine months ended September 30, 2023 and 2022, respectively, within License and development service revenue in our Condensed Consolidated Statements of Operations. As of December 31, 2022, substantially all the revenue related to this performance obligation had been recognized.

Access Rights and Option Continuation Periods

Under the First Gilead Collaboration Agreement Amendment, Gilead has exclusive access to our current programs as well as the future programs for a period of ten years, contingent upon option continuation payments totaling $300 million, consisting of a $100 million payment on each of the fourth, sixth, and eighth anniversaries of the agreement. We allocated arrangement consideration of $121 million to this performance obligation.

We use a time-elapsed input method to measure progress toward satisfying this obligation, which is the method we believe most faithfully depicts our performance in transferring the promised services during the time period in which Gilead has access to our R&D pipeline. Accordingly, the revenue allocated to this performance obligation is being recognized using this input method over the minimum four-year period. We have determined that Gilead is not obligated to pay the remaining $300 million due over the remainder of the term and excluded these payments from the transaction price. Failure to pay the non-obligatory option continuation payments will result in Gilead’s loss of certain rights to access and obtain licenses to the programs arising from our R&D pipeline.

We recognized revenue of $8 million associated with the performance of this obligation for each of the three months ended September 30, 2023 and 2022, and $25 million for each of the nine months ended September 30, 2023 and 2022, within Other collaboration revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $62 million of deferred revenue on our Condensed Consolidated Balance Sheet related to this performance obligation.

Revenue from the Taiho Collaboration

In September 2023, under the Taiho collaboration, certain clinical milestones for domvanalimab and zimberelimab were met through the STAR-221 study and Taiho became obligated to pay us $28 million, which is recorded in Receivable from collaboration partners at September 30, 2023 on our Condensed Consolidated Balance Sheet. We determined that we have a performance obligation to perform R&D services for Taiho related to the global development activities for the STAR-221 study in support of the Taiho Territory. We allocated the $28 million to this single performance obligation and recognize the amounts allocated to this service as the performance obligation is satisfied, calculated as an estimated percentage of completion based on management's estimated total effort for the programs.

We recognized revenue of $4 million for both the three and nine months ended September 30, 2023 within License and development service revenue in our Condensed Consolidated Statements of Operations. At September 30, 2023, we had $24 million of deferred revenue remaining on our Condensed Consolidated Balance Sheet related to this performance obligation, allocated between current and noncurrent based on the expected timing of future recognition.

Capitalized Costs to Obtain Contracts

We incurred certain costs to obtain the Gilead Collaboration Agreement in 2020 and the First Gilead Collaboration Agreement Amendment in 2021, which consisted of consultant and legal fees. We allocated these costs to the various performance obligations, to be recognized as the underlying performance obligations are satisfied and revenue is recognized.

For the three months ended September 30, 2023 and 2022, the recognized expense was not significant. For each of the nine months ended September 30, 2023 and 2022, we recognized $1 million expense related to these capitalized costs in G&A expense. At September 30, 2023, we had $3 million in capitalized costs to obtain the contracts, of which $1 million was recorded as Prepaid expenses and other current assets and $2 million was recorded as Other noncurrent assets in our Condensed Consolidated Balance Sheet.

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Income Taxes

9 Months Ended

Sep. 30, 2023

Income Tax Disclosure [Abstract]

Income Taxes

Income taxes

The income tax provision or benefit for interim periods is determined using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into consideration in the relevant period. Each quarter, we update the estimate of the annual effective tax rate, and if the estimated tax rate changes, we record a cumulative adjustment to the provision or benefit.

The income tax expense was $2 million for the three months ended September 30, 2023, with an effective tax rate of (2.4%). We did not record a provision for income taxes for the three months ended September 30, 2022. The income tax expense was $5 million and $1 million for the nine months ended September 30, 2023 and 2022, with an effective tax rate of (2.2%) and (0.5%), respectively. The year-over-year increase in the income tax provision was due to an increase in taxable income. We have taxable income compared to book losses before income taxes due to the timing of recognition of deferred revenue for tax purposes and the effects of the mandatory capitalization and amortization of research and development expenses starting in 2022, as required by the 2017 Tax Cuts and Jobs Act. The effective tax rate differs from the U.S. statutory tax rate primarily due to the valuation allowances on our deferred tax assets and state income taxes.

As of September 30, 2023 and December 31, 2022, we have provided a valuation allowance against U.S. federal and state deferred tax assets. We continue to evaluate the realizability of deferred tax assets and the related valuation allowance. If our assessment of the deferred tax assets or the corresponding valuation allowance were to change, we would record the related adjustment to income during the period in which we make the determination.

We recognize interest and penalties associated with uncertain tax benefits as part of the income tax provision. To date, we have not recognized any interest and penalties, nor have we accrued for or made payments for interest and penalties.

We have not been audited by the Internal Revenue Service, or any state or foreign tax authority. We are subject to taxation in the United States and in Australia. Due to net operating loss and research credit carryforwards, all of our tax years, from 2015 to 2022, remain open to U.S. federal and California state tax examinations. In addition, our fiscal years from 2018 to 2022 are open to examination in Australia.

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Net Loss Per Share

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

Net loss per share

The following table summarizes potentially dilutive securities excluded from the computation of diluted net loss per share calculations because they would have been antidilutive (in millions):

	September 30, 2023	September 30, 2022
Common stock options issued and outstanding	13.7	12.3
Restricted stock units issued	1.9	1.4
Employee Stock Purchase Plan shares	0.2	0.1
Total potential dilutive securities	15.8	13.8

We have also excluded the effect of Gilead’s right to purchase additional shares of our common stock from the calculation as these rights had no intrinsic value at either September 30, 2023 or 2022.

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Stock-Based Compensation

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

Stock-based compensation

The following table reflects the components of stock-based compensation expense recognized in our Condensed Consolidated Statements of Operations (in millions):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	8	$	8	$	26	$	24
General and administrative	10		8		29		24
Total stock-based compensation	$	18	$	16	$	55	$	48

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Cash, Cash Equivalents and Marketable Securities

9 Months Ended

Sep. 30, 2023

Cash, Cash Equivalents and Marketable Securities [Abstract]

Cash, Cash Equivalents and Marketable Securities

Cash, cash equivalents and marketable securities

The following table summarizes the amortized cost, gross unrealized gains and losses and the fair value of our cash, cash equivalents and marketable securities, all of which are considered available for sale, by type of securities (in millions):

Types of securities as of September 30, 2023	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Money market funds	$	110	$	—	$	—	$	110
U.S. treasury securities	246		—		(1)		245
Corporate securities and commercial paper	493		—		(2)		491
U.S. government agency securities	96		—		—		96
Certificate of deposit	8		—		—		8
Total cash, cash equivalents and marketable securities	$	953	$	—	$	(3)	$	950

Types of securities as of December 31, 2022	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Money market funds	$	169	$	—	$	—	$	169
U.S. treasury securities	317		—		(3)		314
Corporate securities and commercial paper	635		—		(4)		631
U.S. government agency securities	20		—		—		20
Certificate of deposit	4		—		—		4
Total cash, cash equivalents and marketable securities	$	1,145	$	—	$	(7)	$	1,138

The following table summarizes the fair values of our cash, cash equivalents and marketable securities by location in the Condensed Consolidated Balance Sheets and contractual maturity (in millions):

Location in Condensed Consolidated Balance Sheets	Contractual Maturity	September 30, 2023		December 31, 2022
Cash and cash equivalents	-	$	184	$	206
Marketable securities	Within one year	615		803
Long-term marketable securities	Between one and three years	151		129
Total cash, cash equivalents and marketable securities		$	950	$	1,138

Realized gains or losses recognized on the sale of available-for-sale marketable securities were not material for the three and nine months ended September 30, 2023 and 2022. Realized gains and losses are included in Interest and other income, net, in the Condensed Consolidated Statements of Operations. The cost of a security sold is determined using the specific-identification method.

We limit the credit risk associated with our investments by placing them with banks and institutions we believe are highly credit worthy and investing in highly rated investments. We held a total of 159 and 219 positions in securities which were in unrealized loss positions as of September 30, 2023 and December 31, 2022, respectively. We do not intend to sell our securities with unrealized loss positions and have concluded we will not be required to sell the securities before recovery of the amortized cost for the investment at maturity. No credit related losses have been recognized for any of the periods presented.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash within the Condensed Consolidated Balance Sheets to the total shown in the Condensed Consolidated Statements of Cash Flows (in millions):

	September 30,
	2023		2022
Cash and cash equivalents	$	184	$	218
Restricted cash (included in Other noncurrent assets)	3		3
Total cash, cash equivalents and restricted cash	$	187	$	221

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Condensed Consolidated Balance Sheet Components

9 Months Ended

Sep. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Condensed Consolidated Balance Sheet Components

Condensed consolidated balance sheet components

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in millions):

	September 30, 2023		December 31, 2022
Prepaid expenses and other assets	$	27	$	15
Accrued interest receivable	4		4
Total prepaid expenses and other current assets	$	31	$	19

Other Current Liabilities

Other current liabilities consisted of the following (in millions):

	September 30, 2023		December 31, 2022
Accrued research and development	$	41	$	45
Accrued personnel expenses	22		25
Current portion of lease liabilities	9		3
Income taxes payable	3		—
Other	5		3
Total other current liabilities	$	80	$	76

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Leases

9 Months Ended

Sep. 30, 2023

Leases [Abstract]

Leases

Leases

The following table summarizes our cash and non-cash information related to our operating leases (in millions):

	Nine Months Ended September 30,
	2023		2022
Cash paid for amounts included in measurement of lease liabilities	$	12	$	8
Cash received from tenant improvement allowances	$	8	$	8
Right-of-use assets obtained in exchange for new operating lease liabilities	$	—	$	3
Recognition of tenant improvement allowance receivable included in Other current liabilities	$	4	$	6

As of September 30, 2023 and December 31, 2022, we have provided deposits for letters of credit totaling $3 million to secure our obligations under our leases, which are included in Other noncurrent assets in the Condensed Consolidated Balance Sheets.

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Stockholders' Equity

9 Months Ended

Sep. 30, 2023

Stockholders' Equity Note [Abstract]

Stockholders' Equity

Stockholders' Equity

Gilead Stock Purchase

In June 2023, under the Second Stock Purchase Agreement, Gilead purchased 1.0 million shares of our common stock at the closing day purchase price of $19.26 per share for a total cost of $20 million.

At-the-Market Facility

In February 2023, we entered into an equity distribution agreement pursuant to which we may, from time to time, sell shares of our common stock, par value $0.0001 per share, having an aggregate offering price of up to $200 million. In August 2023, we issued and sold 0.2 million shares of our common stock under this agreement for total net proceeds of $5 million.

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Fair Value Measurements

9 Months Ended

Sep. 30, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair value measurements

We determine the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:

•Level 1 inputs include unadjusted quoted prices in active markets for identical assets or liabilities;

•Level 2 inputs include observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities; quoted prices for identical or similar assets or liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability; and

•Level 3 inputs include unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the underlying asset or liability. Our Level 3 assets and liabilities include those whose fair value measurements are determined using pricing models, discounted cash flow methodologies or similar valuation techniques and significant management judgment or estimation.

Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.

The following tables summarize the types of assets and liabilities measured at fair value on a recurring basis by level within the fair value hierarchy (in millions):

Fair value measurement as of September 30, 2023	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	110	$	—	$	—	$	110
U.S. treasury securities	—		245		—		245
Corporate securities and commercial paper	—		491		—		491
U.S. government agency obligations	—		96		—		96
Certificate of deposit	—		8		—		8
Total assets measured at fair value	$	110	$	840	$	—	$	950
Liabilities
Liability for sale of future royalties	$	—	$	—	$	19	$	19
Total liabilities measured at fair value	$	—	$	—	$	19	$	19

Fair value measurement as of December 31, 2022	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	169	$	—	$	—	$	169
U.S. treasury securities	—		314		—		314
Corporate securities and commercial paper	—		631		—		631
U.S. government agency securities	—		20		—		20
Certificate of deposit	—		4		—		4
Total assets measured at fair value	$	169	$	969	$	—	$	1,138
Liabilities
Liability for sale of future royalties	$	—	$	—	$	17	$	17
Total liabilities measured at fair value	$	—	$	—	$	17	$	17

Liability for Sale of Future Royalties

In 2021, we entered into an agreement with BVF Partners L.P. (BVF), under which BVF funded the discovery and development of compounds for the treatment of inflammatory diseases (the BVF Program) for $15 million in non-refundable payments which were paid in 2021 and 2022. In return, we are obligated to: perform research and development activities in the Program; make contingent payments upon the achievement of certain clinical and regulatory milestones of up to $73 million or $160 million depending on whether the program is solely developed by us or with Gilead if they opt-in under the Gilead Collaboration Agreement; and pay mid- to high-single digit royalties on any net product sales generated by the BVF Program.

We account for the BVF Agreement as a liability primarily because we have significant continuing involvement in generating the cash flows due to BVF. The liability is recorded at fair value by using probability-adjusted discounted cash flows and is revalued each reporting period until the related contingencies have been resolved. The fair value measurement is based on significant unobservable inputs that are reviewed quarterly by management and include, as applicable, estimated probabilities and the timing of achieving specified development, regulatory and commercial milestones as well as estimated annual sales. Significant changes that increase or decrease the probabilities of achieving the related development, regulatory and commercial events or that shorten or lengthen the time required to achieve such events or that increase or decrease estimated annual sales would result in corresponding increases or decreases in the fair values of the obligations, as applicable. Changes in the fair value of this liability related to interest accretion are recognized in Non-operating income (expense) in the Condensed Consolidated Statements of Operations.

During the second quarter of 2023, new preclinical information from our BVF Program led to revised assumptions which decreased the estimated probabilities of success and delayed the projected timing of achieving specified development, regulatory and commercial milestones and commercial sales. These changes in estimates are accounted for prospectively and resulted in a decrease in the imputed effective interest rate on the unamortized portion of the liability to 10.1% commencing with the quarter ended June 30, 2023, compared to 20.6% for the quarters ended March 31, 2023 and prior. The impact of this change on the non-cash interest expense for the quarter and nine months ended September 30, 2023 was not material when compared to the prior year periods. The liability for sale of future royalties is reported in Other noncurrent liabilities in the Condensed Consolidated Balance Sheets and changes were as follows (in millions):

	Nine Months Ended September 30,
	2023		2022
Beginning balance	$	17	$	5
Cash received	—		5
Interest accretion	2		2
Ending balance	$	19	$	12

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Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Pay vs Performance Disclosure
Net loss	$ (71)	$ (75)	$ (80)	$ (65)	$ (67)	$ (68)	$ (226)	$ (200)

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Insider Trading Arrangements

3 Months Ended

9 Months Ended

Sep. 30, 2023

shares

Sep. 30, 2023

shares

Trading Arrangements, by Individual

Name

Juan C. Jaen

Title

President and Director

Rule 10b5-1 Arrangement Adopted

true

Non-Rule 10b5-1 Arrangement Adopted

false

Rule 10b5-1 Arrangement Terminated

false

Non-Rule 10b5-1 Arrangement Terminated

false

Juan C. Jaen [Member]

Trading Arrangements, by Individual

Adoption Date

August 8, 2023

Arrangement Duration

458 days

Aggregate Available

300,000,000,000

300,000,000,000

Officers And Directors Trading Arrangement [Member]

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

The adoption, modification or termination of contracts, instructions or written plans for the purchase or sale of our securities by our Section 16 officers and directors for the three months ended September 30, 2023, which are intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act, were as follows:

Name and Title	Action	Date	Total Shares to be Sold	Expiration Date
Juan C. Jaen President and Director	Adopted	August 8, 2023	300,000	November 8, 2024

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Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2023

Accounting Policies [Abstract]

Basis of Presentation

Basis of Presentation

These interim financial statements should be read in conjunction with the audited Consolidated Financial Statements and the related notes thereto for the year ended December 31, 2022 included in our Annual Report on Form 10-K filed with the SEC on February 28, 2023. There have been no significant changes to our accounting policies as described in Note 2, Summary of significant accounting policies, in the notes to Consolidated Financial Statements in Item 8 of Part II of the Form 10-K.

These interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and include all adjustments consisting of normal recurring adjustments that management believes are necessary for a fair presentation of the periods presented. The Condensed Consolidated Balance Sheet as of December 31, 2022 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements.

Operating results for the nine months ended September 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023 or for any future period.

Use of Estimates

Use of Estimates

The preparation of the Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and related disclosures. We base our estimates on historical experience and on various market-specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Estimates are assessed and updated each period to reflect current information. Actual results may differ materially from those estimates.

Recent Accounting Pronouncements

Recent Accounting Pronouncements

There have been no new accounting pronouncements issued or adopted during the period with a significant impact to our financial statements.

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Revenues (Tables)

9 Months Ended

Sep. 30, 2023

Revenue from Contract with Customer [Abstract]

Summary of Revenues by Collaboration, Category of Revenue and Method of Recognition

The following table summarizes our revenues by collaboration, category of revenue, and the method of recognition (in millions):

			Three Months Ended September 30,				Nine Months Ended September 30,
	Over time	Point in time	2023		2022		2023		2022
Gilead Collaboration
License and R&D services	*		$	20	$	23	$	57	$	48
Access rights	*		8		8		25		25
Taiho Collaboration
R&D services	*		4		—		4		—
Access rights	*		—		2		—		5
Total revenues			$	32	$	33	$	86	$	78

Summary of Revenue Recognized as a Result of Changes in Deferred Revenue

The following table summarizes the revenue recognized as a result of changes in the deferred revenue balance (in millions):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue recognized from amounts included in deferred revenue at the beginning of the period	$	28	$	33	$	79	$	78

Summary of Transaction Price and Allocation of Transaction Price to the Performance Obligations

The following table summarizes the allocation of the transaction price to the distinct performance obligations (in millions):

Allocation to performance obligations	Distinct	Amount
Inflammation target 1	*	$	18
Inflammation target 2	*	17
Total allocated transaction price		$	35

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Net Loss Per Share (Tables)

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Summary of Outstanding Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss per Share

The following table summarizes potentially dilutive securities excluded from the computation of diluted net loss per share calculations because they would have been antidilutive (in millions):

	September 30, 2023	September 30, 2022
Common stock options issued and outstanding	13.7	12.3
Restricted stock units issued	1.9	1.4
Employee Stock Purchase Plan shares	0.2	0.1
Total potential dilutive securities	15.8	13.8

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Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

The following table reflects the components of stock-based compensation expense recognized in our Condensed Consolidated Statements of Operations (in millions):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	8	$	8	$	26	$	24
General and administrative	10		8		29		24
Total stock-based compensation	$	18	$	16	$	55	$	48

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Cash, Cash Equivalents and Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2023

Cash, Cash Equivalents and Marketable Securities [Abstract]

Schedule of Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Our Cash, Cash Equivalents and Marketable Securities Considered as Available for Sale by Type of Securities

The following table summarizes the amortized cost, gross unrealized gains and losses and the fair value of our cash, cash equivalents and marketable securities, all of which are considered available for sale, by type of securities (in millions):

Types of securities as of September 30, 2023	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Money market funds	$	110	$	—	$	—	$	110
U.S. treasury securities	246		—		(1)		245
Corporate securities and commercial paper	493		—		(2)		491
U.S. government agency securities	96		—		—		96
Certificate of deposit	8		—		—		8
Total cash, cash equivalents and marketable securities	$	953	$	—	$	(3)	$	950

Types of securities as of December 31, 2022	Amortized Cost		Unrealized Gain		Unrealized Loss		Fair Value
Money market funds	$	169	$	—	$	—	$	169
U.S. treasury securities	317		—		(3)		314
Corporate securities and commercial paper	635		—		(4)		631
U.S. government agency securities	20		—		—		20
Certificate of deposit	4		—		—		4
Total cash, cash equivalents and marketable securities	$	1,145	$	—	$	(7)	$	1,138

Schedule of Fair Values of Our Cash, Cash Equivalents and Marketable Securities by Location in Condensed Consolidated Balance Sheets and Contractual Maturity

The following table summarizes the fair values of our cash, cash equivalents and marketable securities by location in the Condensed Consolidated Balance Sheets and contractual maturity (in millions):

Location in Condensed Consolidated Balance Sheets	Contractual Maturity	September 30, 2023		December 31, 2022
Cash and cash equivalents	-	$	184	$	206
Marketable securities	Within one year	615		803
Long-term marketable securities	Between one and three years	151		129
Total cash, cash equivalents and marketable securities		$	950	$	1,138

Reconciliation of Cash, Cash Equivalents and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash within the Condensed Consolidated Balance Sheets to the total shown in the Condensed Consolidated Statements of Cash Flows (in millions):

	September 30,
	2023		2022
Cash and cash equivalents	$	184	$	218
Restricted cash (included in Other noncurrent assets)	3		3
Total cash, cash equivalents and restricted cash	$	187	$	221

Schedule of Cash and Cash Equivalents

The following table provides a reconciliation of cash, cash equivalents, and restricted cash within the Condensed Consolidated Balance Sheets to the total shown in the Condensed Consolidated Statements of Cash Flows (in millions):

	September 30,
	2023		2022
Cash and cash equivalents	$	184	$	218
Restricted cash (included in Other noncurrent assets)	3		3
Total cash, cash equivalents and restricted cash	$	187	$	221

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Condensed Consolidated Balance Sheet Components (Tables)

9 Months Ended

Sep. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Summary of Prepaid and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in millions):

	September 30, 2023		December 31, 2022
Prepaid expenses and other assets	$	27	$	15
Accrued interest receivable	4		4
Total prepaid expenses and other current assets	$	31	$	19

Summary of Other Current Liabilities

Other current liabilities consisted of the following (in millions):

	September 30, 2023		December 31, 2022
Accrued research and development	$	41	$	45
Accrued personnel expenses	22		25
Current portion of lease liabilities	9		3
Income taxes payable	3		—
Other	5		3
Total other current liabilities	$	80	$	76

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Leases (Tables)

9 Months Ended

Sep. 30, 2023

Leases [Abstract]

Summary of Cash and Non-cash Information Related to Operating Leases

The following table summarizes our cash and non-cash information related to our operating leases (in millions):

	Nine Months Ended September 30,
	2023		2022
Cash paid for amounts included in measurement of lease liabilities	$	12	$	8
Cash received from tenant improvement allowances	$	8	$	8
Right-of-use assets obtained in exchange for new operating lease liabilities	$	—	$	3
Recognition of tenant improvement allowance receivable included in Other current liabilities	$	4	$	6

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Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2023

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis

The following tables summarize the types of assets and liabilities measured at fair value on a recurring basis by level within the fair value hierarchy (in millions):

Fair value measurement as of September 30, 2023	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	110	$	—	$	—	$	110
U.S. treasury securities	—		245		—		245
Corporate securities and commercial paper	—		491		—		491
U.S. government agency obligations	—		96		—		96
Certificate of deposit	—		8		—		8
Total assets measured at fair value	$	110	$	840	$	—	$	950
Liabilities
Liability for sale of future royalties	$	—	$	—	$	19	$	19
Total liabilities measured at fair value	$	—	$	—	$	19	$	19

Fair value measurement as of December 31, 2022	Level 1		Level 2		Level 3		Total
Assets
Money market funds	$	169	$	—	$	—	$	169
U.S. treasury securities	—		314		—		314
Corporate securities and commercial paper	—		631		—		631
U.S. government agency securities	—		20		—		20
Certificate of deposit	—		4		—		4
Total assets measured at fair value	$	169	$	969	$	—	$	1,138
Liabilities
Liability for sale of future royalties	$	—	$	—	$	17	$	17
Total liabilities measured at fair value	$	—	$	—	$	17	$	17

Summary of Changes of Liabilities for Sale of Future Royalties

The liability for sale of future royalties is reported in Other noncurrent liabilities in the Condensed Consolidated Balance Sheets and changes were as follows (in millions):

	Nine Months Ended September 30,
	2023		2022
Beginning balance	$	17	$	5
Cash received	—		5
Interest accretion	2		2
Ending balance	$	19	$	12

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Organization, Liquidity, and Capital Resources - Additional Information (Details) $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($) segment
Organization [Line Items]
Number of reportable segments	1
Number of operating segments	1
Cash, Cash Equivalents and Investments in Marketable Securities
Organization [Line Items]
Cash and investments | $	$ 950

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Related Party - Gilead Sciences, Inc. - Additional Information (Details) $ / shares in Units, shares in Millions	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2023 USD ($) Program shares	May 31, 2023 USD ($) Program	Oct. 31, 2022	Sep. 30, 2023 USD ($) $ / shares	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) $ / shares	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($) Program shares	Dec. 31, 2020 USD ($) shares
Related Party Transaction [Line Items]
Common stock share value				$ 5,000,000
Amended Investor Rights Agreement
Related Party Transaction [Line Items]
Lockup period			2 years
Extended lockup period			3 years
Gilead Collaboration Agreement
Related Party Transaction [Line Items]
Option payment upon completion of certain IND-enabling activities								$ 60,000,000
Option payment upon achievement of certain development milestones								$ 150,000,000
Amended Gilead Collaboration Agreement
Related Party Transaction [Line Items]
Number of exercise option to programs | Program								3
Option payments received								$ 725,000,000
Removal of option continuation payment under agreement								$ 100,000,000
Option payment upon achievement of certain development milestones		$ 150,000,000
Number of programs, eligible to receive regulatory and commercial milestone payments | Program		2
Related Party
Related Party Transaction [Line Items]
Percentage of outstanding common stock held				19.80%		19.80%
Related Party | Research and Development
Related Party Transaction [Line Items]
Reimbursement from related party for shared costs				$ 22,000,000	$ 27,000,000	$ 89,000,000	$ 93,000,000
Related Party | Purchase Agreement
Related Party Transaction [Line Items]
Issuance of common stock (in shares) | shares	1.0							5.7	6.0
Funds received for stock purchase agreement									$ 200,000,000
Purchase price of common stock allocation to performance obligation									$ 91,000,000
Common stock share value	$ 20,000,000							$ 220,000,000
Percentage of premium purchase price of common stock						20.00%
Weighted average closing price of our common stock on grant date (in dollars per share) | $ / shares				$ 33.54		$ 33.54
Trailing days average closing price						5 days
Related Party | Purchase Agreement | Maximum
Related Party Transaction [Line Items]
Right to purchase additional outstanding voting common stock percentage				35.00%		35.00%
Related Party | Gilead Collaboration Agreement
Related Party Transaction [Line Items]
Collaboration term for current and future clinical programs									10 years
Option continuation payment due upon sixth anniversary of agreement									$ 100,000,000
Upfront cash payment									$ 175,000,000
Option fee per program for all other programs entering clinical development to exercise option								$ 150,000,000
Number of research programs								2
Revenue recognized				$ 28,000,000	$ 31,000,000	$ 82,000,000	$ 73,000,000
Related Party | Gilead Collaboration Agreement | Maximum
Related Party Transaction [Line Items]
Potential regulatory approval milestones payment receivable related to domvanalimab								$ 500,000,000
Related Party | Amended Gilead Collaboration Agreement
Related Party Transaction [Line Items]
Upfront cash payment	$ 35,000,000	$ 17,500,000
Number of research programs | Program	2
Option payment upon completion of certain IND-enabling activities		45,000,000
Related Party | Amended Gilead Collaboration Agreement | Maximum
Related Party Transaction [Line Items]
Regulatory and commercial milestone payments received		$ 375,000,000

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License and Collaborations - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2017	Dec. 31, 2022
License And Collaboration Agreements [Line Items]
Total revenues	$ 32,000,000	$ 33,000,000	$ 86,000,000	$ 78,000,000
Other noncurrent liabilities	145,000,000		145,000,000			$ 140,000,000
Other noncurrent assets ($6 and $2 from a related party)	108,000,000		108,000,000			114,000,000
AstraZeneca Agreement
License And Collaboration Agreements [Line Items]
Development cost recorded within research and development expenses	1,000,000	1,000,000	6,000,000	3,000,000
Other noncurrent liabilities	11,000,000		11,000,000			5,000,000
Gilead Collaboration Agreement
License And Collaboration Agreements [Line Items]
Total revenues			1,000,000
Other noncurrent assets ($6 and $2 from a related party)	6,000,000		6,000,000			$ 2,000,000
Taiho Pharmaceutical Co., Ltd | Taiho Agreement
License And Collaboration Agreements [Line Items]
Option period					5 years
Non refundable and non creditable cash payments					$ 35,000,000
Payment for option exercise	$ 28,000,000
Royalties payable term	10 years
Total revenues	$ 4,000,000	2,000,000	4,000,000	5,000,000
Reimbursement of research and development expense	2,000,000		4,000,000
Taiho Pharmaceutical Co., Ltd | Taiho Agreement | Minimum
License And Collaboration Agreements [Line Items]
Payment for option exercise					3,000,000
Taiho Pharmaceutical Co., Ltd | Taiho Agreement | Maximum
License And Collaboration Agreements [Line Items]
Payment for option exercise					15,000,000
Additional clinical and regulatory milestone payments receivable					130,000,000
Contingent milestone payments receivable					$ 145,000,000
WuXi Biologics License Agreement | anti-CD39 | Research and Development
License And Collaboration Agreements [Line Items]
Development milestone expense	$ 0	$ 0	1,000,000	$ 2,000,000
WuXi Biologics License Agreement | Maximum | anti-PD-1
License And Collaboration Agreements [Line Items]
Clinical, regulatory and commercialization milestone payments			375,000,000
WuXi Biologics License Agreement | Maximum | anti-CD39
License And Collaboration Agreements [Line Items]
Additional clinical, regulatory and commercialization milestone payments			14,000,000
Abmuno License Agreement
License And Collaboration Agreements [Line Items]
Additional clinical, regulatory and commercialization milestone payments			$ 88,000,000

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Revenues - Summary of Revenues by Collaboration, Category of Revenue and Method of Recognition (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
License And Collaboration Agreements [Line Items]
Revenue from contract with customer, excluding assessed tax	$ 32	$ 33	$ 86	$ 78
License and R&D services
License And Collaboration Agreements [Line Items]
Revenue from contract with customer, excluding assessed tax	20	23	57	48
Access rights
License And Collaboration Agreements [Line Items]
Revenue from contract with customer, excluding assessed tax	8	8	25	25
R&D services
License And Collaboration Agreements [Line Items]
Revenue from contract with customer, excluding assessed tax	4	0	4	0
Access rights
License And Collaboration Agreements [Line Items]
Revenue from contract with customer, excluding assessed tax	$ 0	$ 2	$ 0	$ 5

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Revenues - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	May 31, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				$ 32	$ 33	$ 86	$ 78
Contract with customer, liability	$ 429			429		429
Total allocated transaction price						35
Deferred revenue recognized				28	33	79	78
Gilead Collaboration Agreement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax						1
Contract with customer, liability								$ 452
R&D Activities for Domvanalimab
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				1		3	2
Contract with customer, liability	27			27		27
Deferred revenue recognized						34
R&D and Commercialization Activities for Zimberelimab
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				0	8	1	9
Deferred revenue recognized						11
Access Rights and Option Continuation Periods
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				8	8	25	25
Contract with customer, liability	62			62		62
Gilead
Disaggregation of Revenue [Line Items]
Capitalized contract cost, amortization						1	1
Cost sharing receivable	3			3		3
Gilead | Prepaid Expenses and Other Current Assets
Disaggregation of Revenue [Line Items]
Capitalized contract cost, net, current	1			1		1
Gilead | Other Noncurrent Assets
Disaggregation of Revenue [Line Items]
Capitalized contract cost, net, noncurrent	2			2		2
Gilead | Gilead Collaboration Agreement
Disaggregation of Revenue [Line Items]
Upfront cash payment		$ 35
Total allocated transaction price			$ 35
Deferred revenue recognized						$ 121
Current and future programs exclusive access period						10 years
Contingent milestone payments receivable	300			300		$ 300
Option continuation payment receivable upon sixth anniversary of agreement	100			100		$ 100
Performance obligation period						4 years
Gilead | R&D Activities for Inflammation Programs
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				2		$ 3
Contract with customer, liability	32			32		32
Gilead | Etrumadenant License and research and Development Services Agreement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				21	3	39	21
Contract with customer, liability	146			146		146
Deferred revenue recognized						219
Gilead | Quemliclustat, License and R&D services
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				(4)	$ 12	11	$ 16
Contract with customer, liability	138			$ 138		138
Deferred revenue recognized						$ 176
Gilead | Revenue Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenues				88.00%	94.00%	95.00%	94.00%
STAR-221 Development Activities | Taiho Collaboration Agreement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, excluding assessed tax				$ 4		$ 4
Contract with customer, liability	24			$ 24		$ 24
Revenue recognized	$ 28

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Revenues - Summary of Revenue Recognized as a Result of Changes in Deferred Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue from Contract with Customer [Abstract]
Amounts included in deferred revenue at the beginning of the period	$ 28	$ 33	$ 79	$ 78

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Revenues - Summary of Transaction Price and Allocation of Transaction Price to the Performance Obligations (Details) $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($)
License And Collaboration Agreements [Line Items]
Total allocated transaction price	$ 35
Inflammation target 1
License And Collaboration Agreements [Line Items]
Total allocated transaction price	18
Inflammation target 2
License And Collaboration Agreements [Line Items]
Total allocated transaction price	$ 17

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Income Taxes - Additional Information - (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Income tax expense	$ 2,000,000	$ 0	$ 5,000,000	$ 1,000,000
Effective tax rate	(2.40%)		(2.20%)	(0.50%)

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Net Loss Per Share - Summary of Outstanding Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss per Share (Details) - shares shares in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (in shares)	15.8	13.8
Common stock options issued and outstanding
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (in shares)	13.7	12.3
Restricted stock units issued
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (in shares)	1.9	1.4
Employee Stock Purchase Plan shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (in shares)	0.2	0.1

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Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation	$ 18	$ 16	$ 55	$ 48
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation	8	8	26	24
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation	$ 10	$ 8	$ 29	$ 24

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Cash, Cash Equivalents and Marketable Securities - Schedule of Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Our Cash, Cash Equivalents and Marketable Securities Considered as Available for Sale by Type of Securities (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 953	$ 1,145
Unrealized Gain	0	0
Unrealized Loss	(3)	(7)
Fair Value	950	1,138
Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	110	169
Unrealized Gain	0	0
Unrealized Loss	0	0
Fair Value	110	169
U.S. treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	246	317
Unrealized Gain	0	0
Unrealized Loss	(1)	(3)
Fair Value	245	314
Corporate securities and commercial paper
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	493	635
Unrealized Gain	0	0
Unrealized Loss	(2)	(4)
Fair Value	491	631
U.S. government agency securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	96	20
Unrealized Gain	0	0
Unrealized Loss	0	0
Fair Value	96	20
Certificate of deposit
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	8	4
Unrealized Gain	0	0
Unrealized Loss	0	0
Fair Value	$ 8	$ 4

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Cash, Cash Equivalents and Marketable Securities - Schedule of Fair Values of Our Cash, Cash Equivalents and Marketable Securities by Location in Condensed Consolidated Balance Sheets and Contractual Maturity (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Cash, Cash Equivalents and Marketable Securities [Abstract]
Cash and cash equivalents	$ 184	$ 206
Marketable securities	615	803
Long-term marketable securities	151	129
Total cash, cash equivalents and marketable securities	$ 950	$ 1,138

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Cash, Cash Equivalents and Marketable Securities - Additional Information (Details)	9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($) position	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) position
Cash, Cash Equivalents and Marketable Securities [Abstract]
Number of positions in securities in unrealized loss | position	159		219
Credit related losses | $	$ 0	$ 0	$ 0

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Cash, Cash Equivalents and Marketable Securities - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Cash, Cash Equivalents and Marketable Securities [Abstract]
Cash and cash equivalents	$ 184	$ 206	$ 218
Restricted cash (included in Other noncurrent assets)	3		3
Total cash, cash equivalents and restricted cash	$ 187	$ 209	$ 221	$ 151
Restricted Cash, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other noncurrent assets ($6 and $2 from a related party)		Other noncurrent assets ($6 and $2 from a related party)

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Condensed Consolidated Balance Sheet Components - Summary of Prepaid and Other Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Prepaid expenses and other assets	$ 27	$ 15
Accrued interest receivable	4	4
Total prepaid expenses and other current assets	$ 31	$ 19

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Condensed Consolidated Balance Sheet Components - Summary of Other Current Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Accrued research and development	$ 41	$ 45
Accrued personnel expenses	22	25
Current portion of lease liabilities	9	3
Income taxes payable	3	0
Other	5	3
Total other current liabilities	$ 80	$ 76

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Leases - Summary of Cash and Non-cash Information Related to Operating Leases (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Cash paid for amounts included in measurement of lease liabilities	$ 12	$ 8
Cash received from tenant improvement allowances	8	8
Right-of-use assets obtained in exchange for new operating lease liabilities	0	3
Recognition of tenant improvement allowance receivable included in Other current liabilities	$ 4	$ 6

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Leases - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Leases [Abstract]
Deposits for letters of credit	$ 3	$ 3

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Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended			3 Months Ended
	Aug. 31, 2023	Jun. 30, 2023	Feb. 28, 2023	Sep. 30, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Issuance of common stock				$ 5
Common stock, par value (in dollars per share)			$ 0.0001	$ 0.0001	$ 0.0001
At-the-Market Facility
Class of Stock [Line Items]
Sale of stock authorized consideration on transaction			$ 200
Sale of stock, number of shares issued in transaction (in shares)	0.2
Sale of stock, consideration received on transaction	$ 5
Second Stock Purchase Agreement | Gilead
Class of Stock [Line Items]
Issuance of common stock (in shares)		1.0
Purchase price per share (in dollars per share)		$ 19.26
Issuance of common stock		$ 20

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Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value On Recurring Basis - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 950	$ 1,138
Total liabilities measured at fair value	19	17
Liability for sale of future royalties
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total liabilities measured at fair value	19	17
Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	110	169
U.S. treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	245	314
Corporate securities and commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	491	631
U.S. government agency obligations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	96
U.S. government agency securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		20
Certificate of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	8	4
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	110	169
Total liabilities measured at fair value	0	0
Level 1 | Liability for sale of future royalties
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total liabilities measured at fair value	0	0
Level 1 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	110	169
Level 1 | U.S. treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 1 | Corporate securities and commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 1 | U.S. government agency obligations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0
Level 1 | U.S. government agency securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0
Level 1 | Certificate of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	840	969
Total liabilities measured at fair value	0	0
Level 2 | Liability for sale of future royalties
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total liabilities measured at fair value	0	0
Level 2 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 2 | U.S. treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	245	314
Level 2 | Corporate securities and commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	491	631
Level 2 | U.S. government agency obligations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	96
Level 2 | U.S. government agency securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		20
Level 2 | Certificate of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	8	4
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Total liabilities measured at fair value	19	17
Level 3 | Liability for sale of future royalties
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total liabilities measured at fair value	19	17
Level 3 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 3 | U.S. treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 3 | Corporate securities and commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Level 3 | U.S. government agency obligations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	0
Level 3 | U.S. government agency securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value		0
Level 3 | Certificate of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 0	$ 0

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Fair Value Measurements - Additional Information (Details) - BVF Partners L.P. - USD ($) $ in Millions	3 Months Ended			9 Months Ended	12 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
BVF Agreement
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Non-refundable payments received					$ 15	$ 15
Imputed effective rate of interest on unamortized portion of liability	10.10%	20.60%	20.60%	20.60%
BVF Agreement | Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent payments upon achievement of certain clinical and regulatory milestones						73
Gilead Collaboration Agreement | Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent payments upon achievement of certain clinical and regulatory milestones						$ 160

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Fair Value Measurements - Summary of Changes of Liabilities for Sale of Future Royalties (Details) - BVF Partners L.P. - BVF Agreement - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 17	$ 5
Cash received	0	5
Interest accretion	2	2
Ending balance	$ 19	$ 12