AnaptysBio (ANAB) 10-Q5 Aug 242024 Q2 Quarterly reportFinancial data

Company Profile

Cover Page

Cover Page - shares	6 Months Ended
Cover Page - shares	Jun. 30, 2024	Jul. 31, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	001-37985
Entity Registrant Name	ANAPTYSBIO, INC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-3828755
Entity Address, Address Line One	10770 Wateridge Circle
Entity Address, Address Line Two	Suite 210
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92121
City Area Code	858
Local Phone Number	362-6295
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	ANAB
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		27,449,316
Entity Central Index Key	0001370053
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q2
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 71,821	$ 35,965
Receivables from collaborative partners	9,007	6,851
Short-term investments	278,983	354,939
Prepaid expenses and other current assets	7,539	9,080
Total current assets	367,350	406,835
Property and equipment, net	1,833	2,098
Operating lease right-of-use assets	15,291	16,174
Long-term investments	42,646	27,026
Other long-term assets	256	256
Total assets	427,376	452,389
Current liabilities:
Accounts payable	4,890	4,698
Accrued expenses	33,680	30,967
Current portion of operating lease liability	1,850	1,777
Total current liabilities	40,420	37,442
Liability related to sale of future royalties	361,981	310,807
Operating lease liability, net of current portion	15,096	16,037
Stockholders’ equity:
Preferred stock, $0.001 par value, 10,000 shares authorized and no shares, issued or outstanding at June 30, 2024 and December 31, 2023, respectively	0	0
Common stock, $0.001 par value, 500,000 shares authorized, 27,434 shares and 26,597 shares issued and outstanding at June 30, 2024 and December 31, 2023, respectively	27	27
Additional paid in capital	714,959	702,969
Accumulated other comprehensive loss	(415)	(797)
Accumulated deficit	(704,692)	(614,096)
Total stockholders’ equity	9,879	88,103
Total liabilities and stockholders’ equity	$ 427,376	$ 452,389

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	27,434,033	26,597,000
Common stock, shares outstanding (in shares)	27,434,033	26,597,000

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Collaboration revenue	$ 10,971	$ 3,460	$ 18,150	$ 4,834
Operating expenses:
Research and development	41,997	32,923	79,039	67,880
General and administrative	9,295	10,680	21,633	21,498
Total operating expenses	51,292	43,603	100,672	89,378
Loss from operations	(40,321)	(40,143)	(82,522)	(84,544)
Other (expense) income, net:
Interest income	4,623	4,653	9,207	9,139
Non-cash interest expense for the sale of future royalties	(10,953)	(4,358)	(17,270)	(8,694)
Other (expense) income, net	0	3	(2)	(1)
Total other (expense) income, net	(6,330)	298	(8,065)	444
Loss before income taxes	(46,651)	(39,845)	(90,587)	(84,100)
Provision for income taxes	(9)		(9)	0
Net loss	(46,660)	(39,845)	(90,596)	(84,100)
Unrealized gain (loss) on available for sale securities	209	(344)	382	1,635
Comprehensive loss	$ (46,451)	$ (40,189)	$ (90,214)	$ (82,465)
Net loss per common share:
Basic (in dollars per share)	$ (1.71)	$ (1.50)	$ (3.35)	$ (3.08)
Diluted (in dollars per share)	$ (1.71)	$ (1.50)	$ (3.35)	$ (3.08)
Weighted-average number of shares outstanding:
Basic (in shares)	27,356	26,629	27,079	27,288
Diluted (in shares)	27,356	26,629	27,079	27,288

Consolidated Statements of Op_2

Consolidated Statements of Operations and Comprehensive Loss (Parenthetical)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	Collaboration Revenue [Member]	Collaboration Revenue [Member]	Collaboration Revenue [Member]	Collaboration Revenue [Member]

Consolidated Statement of Stock

Consolidated Statement of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2022		28,513,000
Stockholders' equity, beginning balance at Dec. 31, 2022	$ 262,103	$ 29	$ 717,797	$ (5,246)	$ (450,477)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of options and employee stock purchase plan (in shares)		55,000
Issuance of common stock from exercises of options and employee stock purchase plan	1,222		1,222
Issuance of common stock upon vesting of restricted stock units (in shares)		39,000
Repurchases and retirements of common stock (in shares)		(1,589,000)
Repurchases and retirements of common stock	(38,816)	$ (2)	(38,814)
Stock-based compensation	8,860		8,860
Comprehensive gain (loss), net	1,979			1,979
Net loss	(44,255)				(44,255)
Stockholders' equity, ending balance (in shares) at Mar. 31, 2023		27,018,000
Stockholders' equity, ending balance at Mar. 31, 2023	191,093	$ 27	689,065	(3,267)	(494,732)
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2022		28,513,000
Stockholders' equity, beginning balance at Dec. 31, 2022	262,103	$ 29	717,797	(5,246)	(450,477)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(84,100)
Stockholders' equity, ending balance (in shares) at Jun. 30, 2023		26,531,000
Stockholders' equity, ending balance at Jun. 30, 2023	148,450	$ 27	686,611	(3,611)	(534,577)
Stockholders' equity, beginning balance (in shares) at Mar. 31, 2023		27,018,000
Stockholders' equity, beginning balance at Mar. 31, 2023	191,093	$ 27	689,065	(3,267)	(494,732)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of options and employee stock purchase plan (in shares)		48,000
Issuance of common stock from exercises of options and employee stock purchase plan	775		775
Repurchases and retirements of common stock (in shares)		(535,000)
Repurchases and retirements of common stock	(11,656)		(11,656)
Stock-based compensation	8,427		8,427
Comprehensive gain (loss), net	(344)			(344)
Net loss	(39,845)				(39,845)
Stockholders' equity, ending balance (in shares) at Jun. 30, 2023		26,531,000
Stockholders' equity, ending balance at Jun. 30, 2023	$ 148,450	$ 27	686,611	(3,611)	(534,577)
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2023	26,597,000	26,597,000
Stockholders' equity, beginning balance at Dec. 31, 2023	$ 88,103	$ 27	702,969	(797)	(614,096)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of options and employee stock purchase plan (in shares)		53,000
Issuance of common stock from exercises of options and employee stock purchase plan	811		811
Issuance of common stock upon vesting of restricted stock units (in shares)		1,014,000
Net share settlement of restricted stock units (in shares)		(347,000)
Net share settlement of restricted stock units	(7,504)		(7,504)
Stock-based compensation	10,131		10,131
Comprehensive gain (loss), net	173			173
Net loss	(43,936)				(43,936)
Stockholders' equity, ending balance (in shares) at Mar. 31, 2024		27,317,000
Stockholders' equity, ending balance at Mar. 31, 2024	$ 47,778	$ 27	706,407	(624)	(658,032)
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2023	26,597,000	26,597,000
Stockholders' equity, beginning balance at Dec. 31, 2023	$ 88,103	$ 27	702,969	(797)	(614,096)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ (90,596)
Stockholders' equity, ending balance (in shares) at Jun. 30, 2024	27,434,033	27,434,000
Stockholders' equity, ending balance at Jun. 30, 2024	$ 9,879	$ 27	714,959	(415)	(704,692)
Stockholders' equity, beginning balance (in shares) at Mar. 31, 2024		27,317,000
Stockholders' equity, beginning balance at Mar. 31, 2024	47,778	$ 27	706,407	(624)	(658,032)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of options and employee stock purchase plan (in shares)		75,000
Issuance of common stock from exercises of options and employee stock purchase plan	1,008		1,008
Issuance of common stock upon vesting of restricted stock units (in shares)		42,000
Stock-based compensation	7,544		7,544
Comprehensive gain (loss), net	209			209
Net loss	$ (46,660)				(46,660)
Stockholders' equity, ending balance (in shares) at Jun. 30, 2024	27,434,033	27,434,000
Stockholders' equity, ending balance at Jun. 30, 2024	$ 9,879	$ 27	$ 714,959	$ (415)	$ (704,692)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (90,596)	$ (84,100)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	317	329
Stock-based compensation	17,675	17,287
Accretion/amortization of investments, net	(5,445)	(4,374)
Amortization of right-of-use assets – operating	883	851
Non-cash interest expense	17,270	8,694
Changes in operating assets and liabilities:
Receivables from collaborative partners	(2,156)	(1,763)
Prepaid expenses and other assets	1,499	(1,241)
Accounts payable and other liabilities	2,846	15,138
Operating lease liabilities	(868)	(798)
Net cash used in operating activities	(58,575)	(49,977)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investments	(208,149)	(167,564)
Sales and maturities of investments	274,383	232,870
Purchases of property and equipment	(60)	(365)
Net cash provided by investing activities	66,174	64,941
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	1,790	2,048
Repurchase and retirements of common stock	0	(50,000)
Proceeds from the sale of future royalties	50,000	0
Payment for net share settlement of equity awards	(7,504)	0
Repayment of liability for sale of future royalties	(15,993)	(3,071)
Payments for debt issuance costs	(36)	(43)
Net cash provided by (used in) financing activities	28,257	(51,066)
Net increase (decrease) in cash and cash equivalents	35,856	(36,102)
Cash and cash equivalents, beginning of period	35,965	71,308
Cash and cash equivalents, end of period	71,821	35,206
Non-cash investing and financing activities:
Amounts accrued for property and equipment	0	52
Amounts accrued for issuance costs related to the sale of future royalties	67	0
Amounts accrued for repurchases of common stock	0	472
Receivable related to issuance of common stock, upon exercise of stock options	$ 29	$ (51)

Description of the Business

Description of the Business	6 Months Ended
Description of the Business	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business	Description of the Business AnaptysBio, Inc. (“we,” “us,” “our,” or the “Company”) was incorporated in the state of Delaware in November 2005. We are a clinical-stage biotechnology company focused on delivering innovative immunology therapeutics. We are developing immune cell modulating antibodies, including two wholly owned checkpoint agonists in clinical-stage development, for autoimmune and inflammatory diseases: rosnilimab, our PD-1 agonist in a Phase 2b trial for the treatment of moderate-to-severe rheumatoid arthritis (“RA”) and a Phase 2 trial for the treatment of moderate-to-severe ulcerative colitis (“UC”); and ANB032, our BTLA agonist, in a Phase 2b trial for the treatment of moderate-to-severe atopic dermatitis (“AD”). We also have other immune cell modulator candidates in our portfolio, including ANB033, an anti-CD122 antagonist antibody, entering a Phase 1 trial and ANB101, a BDCA2 modulator antibody, in preclinical development. In addition, we have developed two cytokine antagonists that we are exploring options for out-licensing: imsidolimab, our anti-IL-36R antibody, that has completed Phase 3 trials for the treatment of generalized pustular psoriasis (“GPP”), and etokimab, our anti-IL-33 antagonist that is Phase 2/3 ready. We have also discovered multiple therapeutic antibodies licensed to GlaxoSmithKline, Inc. (“GSK”) in a financial collaboration for immuno-oncology, including an anti-PD-1 antagonist antibody ( Jemperli (dostarlimab-gxly) or “ Jemperli ”) and an anti-TIM-3 antagonist antibody (cobolimab, GSK4069889). We currently recognize revenue from milestones and royalties achieved under our immuno-oncology collaboration with GSK. Since our inception, we have devoted our primary effort to research and development activities. Our financial support has been provided primarily from the sale of our common stock, royalty monetizations, as well as through funds received under our collaborative research and development agreements. Going forward, as we continue our expansion, we may seek additional financing and/or strategic investments. However, there can be no assurance that any additional financing or strategic investments will be available to us on acceptable terms, if at all. If events or circumstances occur such that we do not obtain additional funding, we will most likely be required to reduce our plans and/or certain discretionary spending, which could have a material adverse effect on our ability to achieve our intended business objectives. AnaptysBio management believes our currently available resources will provide sufficient funds to enable us to meet our operating plans for at least the next twelve months from the issuance of our consolidated financial statements. The accompanying consolidated financial statements do not include any adjustments that might be necessary if we are unable to continue as a going concern.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
Summary of Significant Accounting Policies	Jun. 30, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and note disclosures normally included in annual financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been omitted. The accompanying unaudited consolidated financial statements include all known adjustments necessary for a fair presentation of the results of interim periods as required by U.S. GAAP. These adjustments consist primarily of normal recurring accruals and estimates that impact the carrying value of assets and liabilities. Operating results for the six months ended June 30, 2024 are not necessarily indicative of the results that may be expected for the year ending December 31, 2024. The financial statements should be read in conjunction with our audited financial statements for the year ended December 31, 2023 included in our Annual Report on Form 10-K. Basis of Consolidation The accompanying consolidated financial statements include us and our wholly owned Australian subsidiary. All intercompany accounts and transactions have been eliminated in consolidation. We operate in one reportable segment, and our functional and reporting currency is the U.S. dollar. Use of Estimates The preparation of the accompanying consolidated financial statements in conformity with U.S. GAAP requires our management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. We base our estimates and assumptions on historical experience when available and on various factors that we believe to be reasonable under the circumstances. Significant estimates relied upon in preparing these financial statements include estimates related to revenue recognition, accrued research and development expenses, stock-based compensation, and the liability related to the sale of future royalties. We evaluate our estimates and assumptions on an ongoing basis. Our actual results could differ from these estimates under different assumptions or conditions. Net Loss Per Common Share Basic net loss per common share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted-average number of common equivalent shares outstanding for the period, as well as any dilutive effect from outstanding stock options and warrants using the treasury stock method. For each period presented, there is no difference in the number of shares used to calculate basic and diluted net loss per share. The following table sets forth the weighted-average o utstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because to do so would be anti-dilutive (in common stock equivalent shares): Three Months Ended Six Months Ended (in thousands) 2024 2023 2024 2023 Options to purchase common stock 6,148 4,332 6,113 4,443 Restricted Stock Units 249 413 655 425 Total 6,397 4,745 6,768 4,868 Accounting Pronouncements We have implemented all new accounting pronouncements that are in effect and may have an impact on our consolidated financial statements. Unless otherwise discussed, we believe the impact of any recently issued and not yet effective pronouncements will not have a material impact on our consolidated financial statements. Recent Accounting Pronouncements Not Yet Adopted In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures , which requires enhanced disclosure of significant segment expenses on an annual and interim basis. The guidance will be effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning December 15, 2024, with early adoption permitted. Upon adoption, the guidance should be applied retrospectively to all prior periods presented in the financial statements. We are currently assessing the impact that this standard will have on our consolidated financial statements. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures Income Taxes , which improves the transparency of income tax disclosures by requiring consistent categories and greater disaggregation of information in the effective tax rate reconciliation and income taxes paid disaggregated by jurisdiction. It also includes certain other amendments to improve the effectiveness of income tax disclosures. This guidance will be effective for the annual periods beginning after December 15, 2024. Early adoption is permitted. Upon adoption, the guidance can be applied prospectively or retrospectively. We are currently assessing the impact that this standard will have on our consolidated financial statements.

Balance Sheet Accounts and Supp

Balance Sheet Accounts and Supplemental Disclosures	6 Months Ended
Balance Sheet Accounts and Supplemental Disclosures	Jun. 30, 2024
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Accounts and Supplemental Disclosures	Balance Sheet Accounts and Supplemental Disclosures Property and Equipment, Net Property and equipment, net consist of the following: (in thousands) June 30, 2024 December 31, 2023 Laboratory equipment $ 6,489 $ 6,473 Office furniture and equipment 1,654 1,640 Leasehold improvements 203 203 Property and equipment, gross 8,346 8,316 Less: accumulated depreciation and amortization (6,513) (6,218) Total property and equipment, net $ 1,833 $ 2,098 Accrued Expenses Accrued expenses consist of the following: (in thousands) June 30, 2024 December 31, 2023 Accrued compensation and related expenses $ 5,421 $ 7,201 Accrued professional fees and other expenses 988 1,412 Accrued research, development and manufacturing expenses 26,815 21,898 Accrued for repurchases of common stock 456 456 Total accrued expenses $ 33,680 $ 30,967

Collaborative Research and Deve

Collaborative Research and Development Agreements	6 Months Ended
Collaborative Research and Development Agreements	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Collaborative Research and Development Agreements	Collaborative Research and Development Agreements GSK Collaboration In March 2014, we entered into a Collaboration and Exclusive License Agreement (the “GSK Agreement”) with TESARO, Inc. (“Tesaro”), an oncology-focused biopharmaceutical company now a part of GSK (Tesaro and GSK are hereinafter referred to, collectively, as “GSK”). Currently, under the GSK Agreement, GSK is developing Jemperli as a monotherapy for various solid tumor indications. In addition, GSK is developing dostarlimab in combination with additional therapies under the collaboration, including with another development program from the GSK Agreement: cobolimab, an anti-TIM-3 antibody, in 2L NSCLC. In October 2023, Amendment No. 5 to the GSK Agreement (the “GSK Amendment No. 5”) was agreed by both parties to terminate the anti-LAG-3 antagonist antibody development program under the GSK Agreement. In accordance with the GSK Agreement and the GSK Amendment No. 5, we have regained full global rights to the anti-LAG-3 antagonist antibody development program. For each remaining development program under the GSK Agreement, we are eligible to receive milestone payments if certain preclinical and clinical trial events are achieved by GSK, if certain U.S. and European regulatory submissions and approvals in multiple indications are achieved, and upon the achievement of specified levels of annual worldwide net sales. We will also be eligible to receive tiered 4-8% royalties related to worldwide net sales of products developed under the collaboration. On October 23, 2020, Amendment No. 3 to the GSK Agreement (the “GSK Amendment No. 3”) was agreed to by both parties to permit GSK to conduct development and commercialization in combination with any third-party molecules of Zejula, an oral, once-daily poly (ADP-ribose) polymerase (PARP) inhibitor (“Zejula”). Under GSK Amendment No. 3, we were granted increased royalties upon sales of Jemperli , equal to 8% of Net Sales (as defined in the GSK Agreement) below $1.0 billion and from 12% up to 25% of Net Sales above $1.0 billion. Unless earlier terminated by either party upon specified circumstances, the GSK Agreement will terminate, with respect to each specific developed product, upon the later of the 12th anniversary of the first commercial sale of the product or the expiration of the last to expire of any patent. We assessed these arrangements in accordance with ASC 606 and concluded that the contract counterparty, GSK, is a customer. We identified the following material promises under the GSK Agreement: (1) the licenses under certain patent rights and transfer of certain development and regulatory information, (2) research and development (“R&D”) services, and (3) joint steering committee meetings. We considered the research and discovery capabilities of GSK for these specific programs and the fact that the discovery and optimization of these antibodies is proprietary and could not, at the time of contract inception, be provided by other vendors, to conclude that the license does not have stand-alone functionality and is therefore not distinct. Additionally, we determined that the joint steering committee participation would not have been provided without the R&D services and GSK Agreement. Based on these assessments, we identified all services to be interrelated and therefore concluded that the promises should be combined into a single performance obligation at the inception of the arrangement. As of June 30, 2024, the transaction price for the GSK Agreement and its associated amendments includes the upfront payment, research reimbursement revenue and milestones and royalties earned to date, which are allocated in their entirety to the single performance obligation. We recognized $11.0 million and $18.2 million in royalty revenue during the three and six months ended June 30, 2024, respectively, related to GSK’s net sales of Jemperli and Zejula during the period, which we estimate based on either GSK’s prior sales experience or actuals. Of the royalty revenue recognized during the three and six months ended June 30, 2024, $10.1 million and $16.3 million, respectively, is Jemperli non-cash revenue related to the Jemperli Royalty Monetization Agreement and $0.9 million and $1.9 million, respectively, is Zejula non-cash revenue related to the Zejula Royalty Monetization Agreement, each of such agreements as described in Note 5. We recognized $3.5 million and $4.8 million in royalty revenue during the three and six months ended June 30, 2023, respectively, related to GSK’s net sales of Zejula and Jemperli during the period based on GSK’s prior sales experience or actuals. Of the royalty revenue recognized during the three and six months ended June 30, 2023, $2.8 million and $3.3 million is Jemperli non-cash revenue related to the Jemperli Royalty Monetization Agreement and $0.7 million and $1.5 million is Zejula non-cash revenue related to the Zejula Royalty Monetization Agreement. GSK reports sales information to us on a one quarter lag and differences between actual and estimated royalty revenues will be adjusted in the following quarter. All royalty revenue related to Zejula global net sales starting July 2022 will be paid directly to a wholly owned subsidiary of DRI Healthcare Trust (“DRI”) pursuant to the Zejula Royalty Monetization Agreement, as described in Note 5. No clinical milestones were recognized during the three and six months ended June 30, 2024 and 2023. No other future clinical or regulatory milestones have been included in the transaction price, as all milestone amounts were subject to the revenue constraint. As part of the constraint evaluation, we considered numerous factors including the fact that the receipt of milestones is outside of our control and contingent upon success in future clinical trials, an outcome that is difficult to predict, and GSK’s efforts. Any consideration related to sales-based milestones, including royalties, will be recognized when the related sales occur as they were determined to relate predominantly to the intellectual property license granted to GSK and therefore have also been excluded from the transaction price. We will re-evaluate the variable transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. Milestones under the GSK Agreement are as follows: Anti-PD-1 ( Jemperli /Dostarlimab) Anti-TIM-3 Milestone Event Amount Quarter Recognized Amount Quarter Recognized Initiated in vivo toxicology studies using good laboratory practices (GLPs) $1.0M Q2'15 $1.0M Q4'15 IND clearance from the FDA $4.0M Q1'16 $4.0M Q2'16 Phase 2 clinical trial initiation $3.0M Q2'17 $3.0M Q4'17 Phase 3 clinical trial initiation - first indication $5.0M Q3'18 $5.0M Q4'22 Phase 3 clinical trial initiation - second indication $5.0M Q2'19 $5.0M — Filing of the first BLA (1) - first indication $10.0M Q1'20 $10.0M — Filing of the first MAA (2) - first indication $5.0M Q1'20 $5.0M — Filing of the first BLA - second indication $10.0M Q1'21 $10.0M — First BLA approval - first indication $20.0M Q2'21 $20.0M — First MAA approval - first indication $10.0M Q2'21 $10.0M — First BLA approval - second indication $20.0M Q3'21 $20.0M — Filing of the first MAA - second indication (3) $5.0M — $5.0M — First MAA approval - second indication (3) $10.0M — $10.0M — First commercial sales milestone (3) $15.0M — $15.0M — Second commercial sales milestone (3) $25.0M — $25.0M — Third commercial sales milestone (3) $50.0M — $50.0M — Fourth commercial sales milestone $75.0M — $75.0M — Milestones recognized through June 30, 2024 $93.0M — $13.0M — Milestones that may be recognized in the future $180.0M — $260.0M — (1) Biologics License Application (“BLA”) (2) Marketing Authorization Application (“MAA”) (3) For Jemperli , the filing and approval of the first MAA for a second indication and first three commercial sales milestones are included as part of the royalty monetization agreement with Sagard (as defined below), see Note 5. Cash is generally received within 30 days of milestone achievement. Centessa On November 24, 2023, we entered into an exclusive license agreement (as amended, the “Centessa Agreement”) with Centessa Pharmaceuticals (UK) Limited (“Centessa”), pursuant to which we acquired the exclusive global development and commercialization rights to a blood dendritic cell antigen 2 (BDCA2) modulator antibody portfolio, including lead asset CBS004 (renamed ANB101), CBS008 (renamed ANB102) and the related family of backup antibodies, for the treatment of autoimmune and inflammatory diseases. In connection with the Centessa Agreement, we paid Centessa an upfront cash payment of $4.0 million and an additional cash payment of $3.0 million as reimbursement to Centessa for manufacturing costs incurred. There were $0.3 million in transaction costs incurred. The total transaction amount of $7.3 million was expensed as in-process research and development and classified as an operating activity in the statement of cash flows. We accounted for the transaction as an asset acquisition as the set of acquired assets did not constitute a business. Under the terms of the agreement, Centessa may be entitled to receive potential future payments of up to $10.0 million upon the achievement of a certain event-based milestone and would be entitled to receive on a product-by-product and country-by-country basis, a royalty of low single digits on annual net sales of any product in the territory in each calendar year. As of June 30, 2024, achievement of the milestone is not probable and, therefore, we have not recognized a liability for the associated $10.0 million contingent consideration.

Sale of Future Royalties

Sale of Future Royalties	6 Months Ended
Sale of Future Royalties	Jun. 30, 2024
Other Liabilities Disclosure [Abstract]
Sale of Future Royalties	Sale of Future Royalties Jemperli Royalty Monetization Agreement In October 2021, we signed a royalty monetization agreement (“ Jemperli Royalty Monetization Agreement”) with Sagard Healthcare Royalty Partners, LP (“Sagard”). Under the terms of the Jemperli Royalty Monetization Agreement, we received $250.0 million in exchange for royalties and milestones payable to us under our GSK collaboration on annual global net sales of Jemperli below $1.0 billion starting in October 2021 (not including any combination products that contain both Jemperli and another Development Antibody (as defined in the Jemperli Royalty Monetization Agreement)). In May 2024, we entered into an amendment to the Jemperli Royalty Monetization Agreement, Amendment No. 1 (the “ Jemperli Amendment”) under which we sold additional receivables to Sagard in exchange for $50.0 million. The Jemperli Amendment now includes all Jemperli sales, expands the definition of Jemperli to include any product containing Jemperli , whether or not such product constitutes a combination product, and increases the threshold amounts of aggregate Jemperli royalties and milestones to be received by Sagard under the Jemperli Royalty Monetization Agreement to either $600.0 million if received by the end of March 31, 2031, or $675.0 million if received thereafter. Once either of these thresholds are met, the Jemperli Royalty Monetization Agreement will expire, resulting in us regaining all subsequent Jemperli royalties and milestones. As of June 30, 2024, Sagard has received a total of $24.5 million in royalties and milestones. The proceeds received from Sagard of $250.0 million and $50.0 million were recorded as a liability, net of transaction costs of $0.4 million and $0.1 million, which will be amortized over the estimated life of the arrangement using the effective interest rate method. The aggregate future estimated payments, less the $299.5 million, net of proceeds, will be recognized as non-cash interest expense over the life of the agreement. Royalty and milestone revenue will be recognized as earned on net sales of Jemperli , and these payments to Sagard will be recorded as a reduction of the liability when paid. As such payments are made to Sagard, the balance of the liability will be effectively repaid over the life of the Jemperli Royalty Monetization Agreement. We estimate the effective interest rate used to record non-cash interest expense under the Jemperli Royalty Monetization Agreement based on the estimate of future royalty payments to be received by Sagard. As of June 30, 2024, the estimated effective rate under the agreement was 17.2%. Over the life of the arrangement, the actual effective interest rate will be affected by the amount and the timing of the royalty payments received by Sagard and changes in our forecasted royalties. At each reporting date, we will reassess our estimate of total future royalty payments to be received and if such payments are materially different than our prior estimates, we will prospectively adjust the imputed interest rate and the related amortization of the royalty obligation. We recognized Jemperli non-cash royalty revenue of approximately $10.1 million and $16.3 million during the three and six months ended June 30, 2024 and approximately $2.8 million and $3.3 million during the three and six months ended June 30, 2023, respectively. We recognized non-cash interest expense of approximately $10.7 million and $16.8 million during the three and six months ended June 30, 2024 and $4.2 million and $8.1 million during the three and six months ended June 30, 2023, respectively. The interest and amortization of issuance costs are reflected as non-cash interest expense for the sale of future royalties in the Consolidated Statements of Operations. The following table shows the activity within the liability account for the six months ended June 30, 2024: (in thousands) June 30, 2024 Liability related to sale of future Jemperli royalties and milestones – balance at 12/31/2023 $ 278,090 Proceeds from sale of future royalties 50,000 Issuance costs related to the sale of future royalties (103) Amortization of issuance costs 28 Royalty and milestone payments to Sagard (14,099) Non-cash interest expense recognized 16,801 Liability related to sale of future royalties and milestones – ending balance $ 330,717 Zejula Royalty Monetization Agreement In October 2020, in connection with GSK Amendment No. 3, GSK agreed, under the terms of a settlement agreement (the “GSK Settlement Agreement”), to pay us a royalty of 0.5% on all GSK net sales of Zejula starting January 1, 2021. In September 2022, we signed a purchase and sale agreement (the “Zejula Royalty Monetization Agreement”) with a wholly owned subsidiary of DRI to monetize all of our future royalties on global net sales of Zejula under the GSK Settlement Agreement. Under the terms of the Zejula Royalty Monetization Agreement, we received $35.0 million in exchange for all royalties payable by GSK to us under the GSK Settlement Agreement on global net sales of Zejula starting in July 2022. In addition, under the Zejula Royalty Monetization Agreement, we are entitled to receive an additional $10.0 million payment from DRI if Zejula is approved by the U.S. Food and Drug Administration for the treatment of endometrial cancer on or prior to December 31, 2025. The proceeds received from DRI of $35.0 million were recorded as a liability, net of transaction costs of $0.2 million, which will be amortized over the estimated life of the arrangement using the effective interest rate method. Royalty revenue will be recognized as earned on net sales of Zejula, and these royalty payments to DRI will be recorded as a reduction of the liability when paid. The aggregate future estimated payments, less the $34.8 million, of net proceeds, will be recorded as non-cash interest expense over the life of the agreement. As such payments are made to DRI, the balance of the liability will be effectively repaid over the life of the Zejula Royalty Monetization Agreement. We recognized Zejula non-cash royalty revenue of approximately $0.9 million and $1.9 million during the three and six months ended June 30, 2024 and $0.7 million and $1.5 million during the three and six months ended June 30, 2023, respectively. We recognized non-cash interest expense of approximately $0.2 million and $0.4 million during the three and six months ended June 30, 2024 and $0.2 million and $0.6 million six months ended June 30, 2023, respectively. The interest and amortization of issuance costs is reflected as non-cash interest expense for the sale of future royalties in the Consolidated Statements of Operations. The following table shows the activity within the liability account for the six months ended June 30, 2024: (in thousands) June 30, 2024 Liability related to sale of future Zejula royalties and milestones – balance at 12/31/2023 $ 32,717 Amortization of issuance costs 15 Royalty and milestone payments to DRI (1,894) Non-cash interest expense recognized 426 Liability related to sale of future royalties and milestones – ending balance $ 31,264

Fair Value Measurements and Ava

Fair Value Measurements and Available for Sale Investments	6 Months Ended
Fair Value Measurements and Available for Sale Investments	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements and Available for Sale Investments	Fair Value Measurements and Available for Sale Investments Fair Value Measurements Our financial instruments consist principally of cash, cash equivalents, short-term and long-term investments, receivables, and accounts payable. Certain of our financial assets and liabilities have been recorded at fair value in the consolidated balance sheet in accordance with the accounting standards for fair value measurements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. Accounting guidance also establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value: Level 1 – Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2 – Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted 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 related assets or liabilities; and Level 3 – Unobservable inputs that are supported by little or no market activities, therefore requiring an entity to develop its own assumptions. Assets and Liabilities Measured at Fair Value on a Recurring Basis The following table summarizes our assets and liabilities that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy: Fair Value Measurements at End of Period Using: (in thousands) Fair Value Quoted Market Prices for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) At June 30, 2024 Money market funds (1) $ 59,280 $ 59,280 $ — $ — Mutual funds (1) 2,737 2,737 — — U.S. Treasury securities (2) 296,797 296,797 — — Agency securities (2) 5,066 — 5,066 — Commercial and corporate obligations (2) 19,766 — 19,766 — At December 31, 2023 Money market funds (1) $ 27,789 $ 27,789 $ — $ — Mutual funds (1) 6,286 6,286 — — U.S. Treasury securities (2) 325,714 325,714 — — Certificates of deposit (2) 244 — 244 — Agency securities (2) 20,253 — 20,253 — Commercial and corporate obligations (2) 35,754 — 35,754 — (1) Included in cash and cash equivalents in the accompanying consolidated balance sheets. (2) Included in short-term or long-term investments in the accompanying consolidated balance sheets depending on the respective maturity date. The following methods and assumptions were used to estimate the fair value of our financial instruments for which it is practicable to estimate that value: Marketable Securities. For fair values determined by Level 1 inputs, which utilize quoted prices in active markets for identical assets, the level of judgment required to estimate fair value is relatively low. For fair values determined by Level 2 inputs, which utilize quoted prices in less active markets for similar assets, the level of judgment required to estimate fair value is also considered relatively low. Fair Value of Other Financial Instruments The carrying amounts of certain of our financial instruments, including cash and cash equivalents, accounts payable, and accrued expenses approximate fair value due to their short-term nature. Available for Sale Investments We invest our excess cash in agency securities, debt instruments of financial institutions and corporations, commercial obligations, and U.S. Treasury securities, which we classify as available-for-sale investments. These investments are carried at fair value and are included in the tables above. The aggregate market value, cost basis, and gross unrealized gains and losses of available-for-sale investments by security type, classified in short-term and long-term investments as of June 30, 2024 are as follows: (in thousands) Amortized Gross Gross Total Agency securities (1) $ 5,074 $ — $ (8) $ 5,066 Commercial and corporate obligations (2) 19,778 — (12) 19,766 U.S. Treasury securities (3) 296,985 27 (215) 296,797 Total available for sale investments $ 321,837 $ 27 $ (235) $ 321,629 (1) Of our outstanding agency securities, $5.1 million have maturity dates of less than one year and $0.0 million have maturity dates between one (2) Of our outstanding commercial and corporate obligations, $19.8 million have maturity dates of less than one year and $0.0 million have a maturity date of between one (3) Of our outstanding U.S. Treasury securities, $254.2 million have maturity dates of less than one year and $42.6 million have a maturity date of between one The aggregate market value, cost basis, and gross unrealized gains and losses of available for sale investments by security type, classified in short-term and long-term investments as of December 31, 2023 are as follows: (in thousands) Amortized Gross Gross Total Agency securities (1) $ 20,322 $ — $ (69) $ 20,253 Certificates of deposit (2) 246 — (2) 244 Commercial and corporate obligations (3) 35,760 77 (83) 35,754 U.S. Treasury securities (4) 326,227 122 (635) 325,714 Total available for sale investments $ 382,555 $ 199 $ (789) $ 381,965 (1) Of our outstanding agency securities, $20.3 million have maturity dates of less than one year and $0.0 million have a maturity date of between one (2) Of our outstanding certificates of deposit, $0.2 million have a maturity date of less than one year and $0.0 million have a maturity date of between one (3) Of our outstanding commercial and corporate obligations, $25.8 million have maturity dates of less than one year and $10.0 million have a maturity date of between one (4) Of our outstanding U.S. Treasury securities, $308.6 million have maturity dates of less than one year and $17.1 million have a maturity date of between one The following tables present gross unrealized losses and fair values for those investments that were in an unrealized loss position as of June 30, 2024 and December 31, 2023, aggregated by investment category and the length of time that individual securities have been in a continuous loss position: June 30, 2024 Less than 12 Months 12 Months or Greater Total (in thousands) Fair Value Gross Fair Value Gross Fair Value Gross Agency securities $ — $ — $ 5,066 $ (8) $ 5,066 $ (8) Commercial and corporate obligations 14,258 (10) 3,804 (2) 18,062 (12) U.S. Treasury Securities 182,460 (119) 52,401 (96) 234,861 (215) Total $ 196,718 $ (129) $ 61,271 $ (106) $ 257,989 $ (235) December 31, 2023 Less than 12 Months 12 Months or Greater Total (in thousands) Fair Value Gross Fair Value Gross Fair Value Gross Agency securities $ 2,530 $ (1) $ 17,723 $ (68) $ 20,253 $ (69) Certificates of Deposit — — 244 (2) 244 (2) Commercial and corporate obligations 5,160 (9) 15,200 (74) 20,360 (83) U.S. Treasury Securities 98,840 (110) 99,000 (525) 197,840 (635) Total $ 106,530 $ (120) $ 132,167 $ (669) $ 238,697 $ (789) As of June 30, 2024 and December 31, 2023, unrealized losses on available-for-sale investments were $0.2 million and $0.8 million, respectively, with unrealized losses of $0.1 million, on available for sale investments that were in an unrealized loss position for greater than 12 months as of June 30, 2024. We do not intend to sell the investments and it is not more likely than not that we will be required to sell the investments before recovery of their amortized cost basis, accordingly, no allowance for credit losses was recorded.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
Stockholders' Equity	Jun. 30, 2024
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Common Stock Of the 500,000,000 shares of common stock authorized , 27,434,033 shares were issued and outstanding as of June 30, 2024. Stock Repurchase Program In January 2023, our Board of Directors authorized a stock repurchase program (the “Repurchase Program”) to repurchase up to $50.0 million of our outstanding common stock, par value $0.001 per share. The Repurchase Program was completed in May 2023. The following table presents the repurchase activity from January 1, 2023 through May 5, 2023, the end date of the Repurchase Program: Total number of shares purchased Average price paid per share Approximate dollar value of shares purchased First Quarter 2023 1,589,424 $ 24.19 $ 38,456 Second Quarter 2023 534,790 21.59 11,544 Total 2,124,214 $ 50,000 The repurchased common stock was subsequently retired after the repurchase and the par value of the shares was charged to common stock. The excess of the repurchase price over the par value was applied against additional paid in capital. Open Market Sales Agreement In November 2022, we entered into the Cowen Sales Agreement with Cowen, through which we may offer and sell shares of our common stock, having an aggregate offering of up to $150.0 million through Cowen as our sales agent. As of June 30, 2024, we had sold no shares under this agreement.

Equity Incentive Plans

Equity Incentive Plans	6 Months Ended
Equity Incentive Plans	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Equity Incentive Plans	Equity Incentive Plans 2017 Equity Incentive Plan In January 2017, our Board of Directors and stockholders approved and adopted the 2017 Equity Incentive Plan (the “2017 Plan”). Under the 2017 Plan, we may grant stock options, stock appreciation rights, restricted stock, restricted stock units and other awards to individuals who are then our employees, officers, directors or consultants. In addition, the number of shares of stock available for issuance under the 2017 Plan were to be automatically increased each January 1, beginning on January 1, 2018, by 4% of the aggregate number of outstanding shares of our common stock as of the immediately preceding December 31 or such lesser number as determined by our Board of Directors. The 2017 Plan automatically increased by 1,063,871 shares as of January 1, 2024. At our annual stockholder meeting on June 12, 2024, the 2017 Plan was amended, eliminating the automatic annual share increase and number of shares available for issuance was increased by 2,700,000 shares. All future share increases will require stockholder approval. As of June 30, 2024, 3,653,227 shares were available for future issuance. Employee Stock Purchase Plan In January 2017, our Board of Directors and stockholders approved and adopted the 2017 Employee Stock Purchase Plan (“ESPP”). In addition, the number shares of stock available for issuance under the ESPP will be automatically increased each January 1, beginning on January 1, 2018, by 1% of the aggregate number of outstanding shares of our common stock as of the immediately preceding December 31 or such lesser number as determined by our Board of Directors. The ESPP automatically increased by 265,967 shares as of January 1, 2024. As of June 30, 2024, 151,842 shares have been issued under the ESPP and 1,946,965 shares were available for future issuance. Stock Options Stock options granted to employees and non-employees generally vest over a four-year period while stock options granted to directors generally vest over a one-year period. Each stock option award has a maximum term of 10 years from the date of grant, subject to earlier cancellation prior to vesting upon cessation of service to us. A summary of the activity related to stock option awards during the six months ended June 30, 2024 is as follows: Shares Subject to Options Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding at January 1, 2024 4,225,615 $ 27.36 7.42 $ 5,827 Granted 2,159,889 $ 21.45 Exercised (74,908) $ 15.57 Forfeitures and cancellations (207,690) $ 33.88 Outstanding at June 30, 2024 6,102,906 $ 25.19 7.89 $ 19,526 Exercisable at June 30, 2024 2,636,860 $ 28.98 6.30 $ 8,469 Total cash received from the exercise of stock options was approximately $1.1 million during the six months ended June 30, 2024. Time-Based Restricted Stock Units Each Restricted Stock Unit (“RSU”) represents one equivalent share of our common stock to be issued after satisfying the applicable continued service-based vesting criteria over a specified period. The fair value of these RSUs is based on the closing price of our common stock on the date of the grant. We measure compensation expense over the expected vesting period on a straight-line basis. The RSUs do not entitle the participants to the rights of holders of common stock, such as voting rights, until the shares are issued. Number of Restricted Stock Units Weighted-Average Grant Date Fair Value Weighted-Average Remaining Contractual Term (in years) Aggregate Outstanding at January 1, 2024 1,481,572 $ 24.80 0.73 $ 31,735 Granted 786,108 $ 21.45 Released (1,055,959) $ 25.94 Forfeitures and cancellations (7,372) $ 22.18 Outstanding at June 30, 2024 1,204,349 $ 21.63 1.82 $ 30,181 RSU expected to vest at June 30, 2024 1,204,349 $ 21.63 1.82 $ 30,181 Stock-Based Compensation Expense We recognize stock-based compensation expense for awards issued to employees and non-employees over the requisite service period based on the estimated grant-date fair value of such awards. We record the expense for stock-based compensation awards subject to performance-based milestone vesting over the requisite service period when management determines that achievement of the milestone is probable. Management evaluates when the achievement of a performance-based milestone is probable based on the expected satisfaction of the performance conditions at each reporting date. The estimated fair values of stock option awards granted were determined on the date of grant using the Black-Scholes option valuation model with the following weighted-average assumptions: Six Months Ended 2024 2023 Risk-free interest rate 4.0 % 3.7 % Expected volatility 78.3 % 86.1 % Expected dividend yield — % — % Expected term (in years) 6.28 5.75 Weighted-average grant date fair value per share $ 15.28 $ 16.50 We determine the appropriate risk-free interest rate, expected term for employee stock-based awards, contractual term for non-employee stock-based awards, and volatility assumptions. The weighted-average expected option term for employee and non-employee stock-based awards reflects the historical option term. Expected volatility incorporates the historical volatility of our stock price. The risk-free interest rate is based upon U.S. Treasury securities with remaining terms similar to the expected or contractual term of the stock-based payment awards. The assumed dividend yield is based on our expectation of not paying dividends in the foreseeable future. Total non-cash stock-based compensation expense for all stock awards that was recognized in the consolidated statements of operations and comprehensive loss is as follows: Three Months Ended Six Months Ended (in thousands) 2024 2023 2024 2023 Research and development $ 3,534 $ 2,683 $ 6,988 $ 5,453 General and administrative 4,010 5,744 (1) 10,687 (2) 11,834 (3) Total $ 7,544 $ 8,427 $ 17,675 $ 17,287 (1) Includes $2.9 million related to 2 year RSU initially issued to our new CEO in March 2022 and now fully recognized. (2) Includes $2.6 million related to 2 year RSU initially issued to our new CEO in March 2022 and now fully recognized. (3) Includes $5.8 million related to 2 year RSU initially issued to our new CEO in March 2022 and now fully recognized. At June 30, 2024, there was $51.2 million of unrecognized compensation cost related to unvested stock option awards, which is expected to be recognized over a remaining weighted-average vesting period of 3.03 years and $22.1 million of unrecognized cost related to unvested RSU awards, which is expected to be recognized over a period of 3.10 years and $0.2 million of unrecognized compensation cost related to the ESPP, which is expected to be recognized over a remaining weighted-average vesting period of 0.38 years.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Leases On May 4, 2020, we entered into a lease agreement with Wateridge Property Owner, LP, with respect to facilities in the building at 10770 Wateridge Circle, San Diego, California 92121 (the “Lease Agreement”). Under the Lease Agreement, we agreed to lease approximately 45,000 square feet of space for a term of 124 months, beginning on April 5, 2021. The terms of the Lease Agreement provide us with an option to extend the term of the lease for an additional five years, as well as a one-time option to terminate the lease after seven years with the payment of a termination fee. The exercise of the lease option is at our sole discretion, which we currently do not anticipate exercising and as such was not recognized as part of the right-of-use asset (the “ROU asset”) and lease liability. The monthly base rent was initially $4.20 per rentable square foot and is increased by 3% annually. Under the Lease Agreement, we are also responsible for our pro rata share of real estate taxes, building insurance, maintenance, direct expenses, and utilities. Upon lease commencement, on April 5, 2021, we recognized an ROU asset of $20.6 million, with a corresponding lease liability of $20.7 million on the consolidated balance sheets. The ROU asset includes adjustments for prepayments, initial direct costs, and lease incentives. As of June 30, 2024, we have recorded $0.3 million as a security deposit in accordance with the terms of the Lease Agreement. Our lease payments are fixed, and we recognize lease expense for leases on a straight-line basis over the lease term. Operating lease ROU assets and lease liabilities are recorded based on the present value of the future minimum lease payments over the lease term at commencement date. As our lease does not provide an implicit rate, we used our incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future payments. The weighted-average discount rate used was 4.0% and the weighted-average remaining lease term is approximately 7.2 years. The following non-cancellable office lease costs are included in our consolidated statements of cash flow (in thousands): Six Months Ended Leases Classification on the Cash Flow 2024 2023 Operating lease cost Operating $ 1,239 $ 1,239 Cash paid for amounts included in the measurement of lease liabilities Operating 1,217 1,181 At June 30, 2024, the future minimum annual obligations for the Company’s operating lease liabilities are as follows (in thousands): Years Ending December 31, 2024 $ 1,241 2025 2,531 2026 2,607 2027 2,685 2028 2,766 Thereafter 7,788 Total minimum payments required 19,618 Less imputed interest (2,672) Total $ 16,946

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net loss	$ (46,660)	$ (43,936)	$ (39,845)	$ (44,255)	$ (90,596)	$ (84,100)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	6 Months Ended
Insider Trading Arrangements	Jun. 30, 2024 shares	Jun. 30, 2024 shares
Trading Arrangements, by Individual
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Paul Lizzul [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		On June 10, 2024, Paul Lizzul, chief medical officer of the Company, entered into a written plan for the potential sale of up to an aggregate 36,500 shares of common stock (the “New Lizzul 10b5-1 Plan”). No trades will occur under the New Lizzul 10b5-1 Plan prior to the termination of Mr. Lizzul’s existing rule 10b5-1 plan, pursuant to its terms. The plan is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act and is scheduled to terminate no later than June 10, 2025.
Name	Paul Lizzul
Title	chief medical officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	June 10, 2024
Expiration Date	June 10, 2025
Arrangement Duration	365 days
Aggregate Available	36,500	36,500
Eric Loumeau [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		On June 10, 2024, Eric Loumeau, chief legal officer of the Company, entered into a written plan for the potential sale of up to an aggregate 77,045 shares of common stock (the “New Loumeau 10b5-1 Plan”). The aggregate number of shares that will be sold under the New Loumeau 10b 5-1 Plan is not yet determinable because the shares available will be net of shares sold to satisfy tax withholding obligations that arise in connection with the vesting and settlement of such restricted stock unit awards. As such, for purposes of this disclosure, the aggregate number of shares of common stock available for sale reflects the aggregate maximum number of shares underlying Mr. Loumeau’s restricted stock units which may be sold, without excluding the shares that will be sold to satisfy the tax withholding obligations. No trades will occur under the New Loumeau 10b5-1 Plan prior to the termination of Mr. Loumeau’s existing 10b5-1 plan, pursuant to its terms. The plan is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act and is scheduled to terminate no later than June 30, 2025.
Name	Eric Loumeau
Title	chief legal officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	June 10, 2024
Expiration Date	June 30, 2025
Arrangement Duration	385 days
Aggregate Available	77,045	77,045
Dennis Mulroy [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		On June 14, 2024, Dennis Mulroy, chief financial officer of the Company, entered into a written plan for the potential sale of up to an aggregate 62,350 shares of common stock (the “New Mulroy 10b5-1 Plan”). The aggregate number of shares that will be sold under the New Mulroy 10b 5-1 Plan is not yet determinable because the shares available will be net of shares sold to satisfy tax withholding obligations that arise in connection with the vesting and settlement of such restricted stock unit awards. As such, for purposes of this disclosure, the aggregate number of shares of common stock available for sale reflects the aggregate maximum number of shares underlying Mr. Mulroy’s restricted stock units which may be sold, without excluding the shares that will be sold to satisfy the tax withholding obligations. No trades will occur under the New Mulroy 10b5-1 Plan prior to the termination of Mr. Mulroy’s existing 10b5-1 plan, pursuant to its terms. The plan is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act and is scheduled to terminate no later than May 15, 2025.
Name	Dennis Mulroy
Title	chief financial officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	June 14, 2024
Expiration Date	May 15, 2025
Arrangement Duration	335 days
Aggregate Available	62,350	62,350

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation
Basis of Consolidation	Basis of Consolidation The accompanying consolidated financial statements include us and our wholly owned Australian subsidiary. All intercompany accounts and transactions have been eliminated in consolidation. We operate in one reportable segment, and our functional and reporting currency is the U.S. dollar.
Use of Estimates	Use of Estimates The preparation of the accompanying consolidated financial statements in conformity with U.S. GAAP requires our management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. We base our estimates and assumptions on historical experience when available and on various factors that we believe to be reasonable under the circumstances. Significant estimates relied upon in preparing these financial statements include estimates related to revenue recognition, accrued research and development expenses, stock-based compensation, and the liability related to the sale of future royalties. We evaluate our estimates and assumptions on an ongoing basis. Our actual results could differ from these estimates under different assumptions or conditions.
Net Loss Per Common Share	Net Loss Per Common Share Basic net loss per common share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted-average number of common equivalent shares outstanding for the period, as well as any dilutive effect from outstanding stock options and warrants using the treasury stock method. For each period presented, there is no difference in the number of shares used to calculate basic and diluted net loss per share.
Accounting Pronouncements and Recent Accounting Pronouncements Not Yet Adopted	Accounting Pronouncements We have implemented all new accounting pronouncements that are in effect and may have an impact on our consolidated financial statements. Unless otherwise discussed, we believe the impact of any recently issued and not yet effective pronouncements will not have a material impact on our consolidated financial statements. Recent Accounting Pronouncements Not Yet Adopted In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures , which requires enhanced disclosure of significant segment expenses on an annual and interim basis. The guidance will be effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning December 15, 2024, with early adoption permitted. Upon adoption, the guidance should be applied retrospectively to all prior periods presented in the financial statements. We are currently assessing the impact that this standard will have on our consolidated financial statements. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures Income Taxes , which improves the transparency of income tax disclosures by requiring consistent categories and greater disaggregation of information in the effective tax rate reconciliation and income taxes paid disaggregated by jurisdiction. It also includes certain other amendments to improve the effectiveness of income tax disclosures. This guidance will be effective for the annual periods beginning after December 15, 2024. Early adoption is permitted. Upon adoption, the guidance can be applied prospectively or retrospectively. We are currently assessing the impact that this standard will have on our consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	6 Months Ended
Summary of Significant Accounting Policies (Tables)	Jun. 30, 2024
Accounting Policies [Abstract]
Schedule of Outstanding Potentially Dilutive Securities Excluded in the Calculation of Diluted Net Loss Per Share	The following table sets forth the weighted-average o utstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because to do so would be anti-dilutive (in common stock equivalent shares): Three Months Ended Six Months Ended (in thousands) 2024 2023 2024 2023 Options to purchase common stock 6,148 4,332 6,113 4,443 Restricted Stock Units 249 413 655 425 Total 6,397 4,745 6,768 4,868

Balance Sheet Accounts and Su_2

Balance Sheet Accounts and Supplemental Disclosures (Tables)	6 Months Ended
	Jun. 30, 2024
Balance Sheet Related Disclosures [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consist of the following: (in thousands) June 30, 2024 December 31, 2023 Laboratory equipment $ 6,489 $ 6,473 Office furniture and equipment 1,654 1,640 Leasehold improvements 203 203 Property and equipment, gross 8,346 8,316 Less: accumulated depreciation and amortization (6,513) (6,218) Total property and equipment, net $ 1,833 $ 2,098
Schedule of Accrued Expenses	Accrued expenses consist of the following: (in thousands) June 30, 2024 December 31, 2023 Accrued compensation and related expenses $ 5,421 $ 7,201 Accrued professional fees and other expenses 988 1,412 Accrued research, development and manufacturing expenses 26,815 21,898 Accrued for repurchases of common stock 456 456 Total accrued expenses $ 33,680 $ 30,967

Collaborative Research and De_2

Collaborative Research and Development Agreements (Tables)	6 Months Ended
Collaborative Research and Development Agreements (Tables)	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Schedule of Milestones Achieved	Milestones under the GSK Agreement are as follows: Anti-PD-1 ( Jemperli /Dostarlimab) Anti-TIM-3 Milestone Event Amount Quarter Recognized Amount Quarter Recognized Initiated in vivo toxicology studies using good laboratory practices (GLPs) $1.0M Q2'15 $1.0M Q4'15 IND clearance from the FDA $4.0M Q1'16 $4.0M Q2'16 Phase 2 clinical trial initiation $3.0M Q2'17 $3.0M Q4'17 Phase 3 clinical trial initiation - first indication $5.0M Q3'18 $5.0M Q4'22 Phase 3 clinical trial initiation - second indication $5.0M Q2'19 $5.0M — Filing of the first BLA (1) - first indication $10.0M Q1'20 $10.0M — Filing of the first MAA (2) - first indication $5.0M Q1'20 $5.0M — Filing of the first BLA - second indication $10.0M Q1'21 $10.0M — First BLA approval - first indication $20.0M Q2'21 $20.0M — First MAA approval - first indication $10.0M Q2'21 $10.0M — First BLA approval - second indication $20.0M Q3'21 $20.0M — Filing of the first MAA - second indication (3) $5.0M — $5.0M — First MAA approval - second indication (3) $10.0M — $10.0M — First commercial sales milestone (3) $15.0M — $15.0M — Second commercial sales milestone (3) $25.0M — $25.0M — Third commercial sales milestone (3) $50.0M — $50.0M — Fourth commercial sales milestone $75.0M — $75.0M — Milestones recognized through June 30, 2024 $93.0M — $13.0M — Milestones that may be recognized in the future $180.0M — $260.0M — (1) Biologics License Application (“BLA”) (2) Marketing Authorization Application (“MAA”) (3) For Jemperli , the filing and approval of the first MAA for a second indication and first three commercial sales milestones are included as part of the royalty monetization agreement with Sagard (as defined below), see Note 5. Cash is generally received within 30 days of milestone achievement.

Sale of Future Royalties (Table

Sale of Future Royalties (Tables)	6 Months Ended
Sale of Future Royalties (Tables)	Jun. 30, 2024
Other Liabilities Disclosure [Abstract]
Schedule of Royalty Transaction Activity	The following table shows the activity within the liability account for the six months ended June 30, 2024: (in thousands) June 30, 2024 Liability related to sale of future Jemperli royalties and milestones – balance at 12/31/2023 $ 278,090 Proceeds from sale of future royalties 50,000 Issuance costs related to the sale of future royalties (103) Amortization of issuance costs 28 Royalty and milestone payments to Sagard (14,099) Non-cash interest expense recognized 16,801 Liability related to sale of future royalties and milestones – ending balance $ 330,717 The following table shows the activity within the liability account for the six months ended June 30, 2024: (in thousands) June 30, 2024 Liability related to sale of future Zejula royalties and milestones – balance at 12/31/2023 $ 32,717 Amortization of issuance costs 15 Royalty and milestone payments to DRI (1,894) Non-cash interest expense recognized 426 Liability related to sale of future royalties and milestones – ending balance $ 31,264

Fair Value Measurements and A_2

Fair Value Measurements and Available for Sale Investments (Tables)	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities that Require Fair Value Measurements on a Recurring Basis	The following table summarizes our assets and liabilities that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy: Fair Value Measurements at End of Period Using: (in thousands) Fair Value Quoted Market Prices for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) At June 30, 2024 Money market funds (1) $ 59,280 $ 59,280 $ — $ — Mutual funds (1) 2,737 2,737 — — U.S. Treasury securities (2) 296,797 296,797 — — Agency securities (2) 5,066 — 5,066 — Commercial and corporate obligations (2) 19,766 — 19,766 — At December 31, 2023 Money market funds (1) $ 27,789 $ 27,789 $ — $ — Mutual funds (1) 6,286 6,286 — — U.S. Treasury securities (2) 325,714 325,714 — — Certificates of deposit (2) 244 — 244 — Agency securities (2) 20,253 — 20,253 — Commercial and corporate obligations (2) 35,754 — 35,754 — (1) Included in cash and cash equivalents in the accompanying consolidated balance sheets. (2) Included in short-term or long-term investments in the accompanying consolidated balance sheets depending on the respective maturity date.
Schedule of Available-for-sale Investments	The aggregate market value, cost basis, and gross unrealized gains and losses of available-for-sale investments by security type, classified in short-term and long-term investments as of June 30, 2024 are as follows: (in thousands) Amortized Gross Gross Total Agency securities (1) $ 5,074 $ — $ (8) $ 5,066 Commercial and corporate obligations (2) 19,778 — (12) 19,766 U.S. Treasury securities (3) 296,985 27 (215) 296,797 Total available for sale investments $ 321,837 $ 27 $ (235) $ 321,629 (1) Of our outstanding agency securities, $5.1 million have maturity dates of less than one year and $0.0 million have maturity dates between one (2) Of our outstanding commercial and corporate obligations, $19.8 million have maturity dates of less than one year and $0.0 million have a maturity date of between one (3) Of our outstanding U.S. Treasury securities, $254.2 million have maturity dates of less than one year and $42.6 million have a maturity date of between one The aggregate market value, cost basis, and gross unrealized gains and losses of available for sale investments by security type, classified in short-term and long-term investments as of December 31, 2023 are as follows: (in thousands) Amortized Gross Gross Total Agency securities (1) $ 20,322 $ — $ (69) $ 20,253 Certificates of deposit (2) 246 — (2) 244 Commercial and corporate obligations (3) 35,760 77 (83) 35,754 U.S. Treasury securities (4) 326,227 122 (635) 325,714 Total available for sale investments $ 382,555 $ 199 $ (789) $ 381,965 (1) Of our outstanding agency securities, $20.3 million have maturity dates of less than one year and $0.0 million have a maturity date of between one (2) Of our outstanding certificates of deposit, $0.2 million have a maturity date of less than one year and $0.0 million have a maturity date of between one (3) Of our outstanding commercial and corporate obligations, $25.8 million have maturity dates of less than one year and $10.0 million have a maturity date of between one (4) Of our outstanding U.S. Treasury securities, $308.6 million have maturity dates of less than one year and $17.1 million have a maturity date of between one
Schedule of Unrealized Loss and Fair Values in a Loss Position	The following tables present gross unrealized losses and fair values for those investments that were in an unrealized loss position as of June 30, 2024 and December 31, 2023, aggregated by investment category and the length of time that individual securities have been in a continuous loss position: June 30, 2024 Less than 12 Months 12 Months or Greater Total (in thousands) Fair Value Gross Fair Value Gross Fair Value Gross Agency securities $ — $ — $ 5,066 $ (8) $ 5,066 $ (8) Commercial and corporate obligations 14,258 (10) 3,804 (2) 18,062 (12) U.S. Treasury Securities 182,460 (119) 52,401 (96) 234,861 (215) Total $ 196,718 $ (129) $ 61,271 $ (106) $ 257,989 $ (235) December 31, 2023 Less than 12 Months 12 Months or Greater Total (in thousands) Fair Value Gross Fair Value Gross Fair Value Gross Agency securities $ 2,530 $ (1) $ 17,723 $ (68) $ 20,253 $ (69) Certificates of Deposit — — 244 (2) 244 (2) Commercial and corporate obligations 5,160 (9) 15,200 (74) 20,360 (83) U.S. Treasury Securities 98,840 (110) 99,000 (525) 197,840 (635) Total $ 106,530 $ (120) $ 132,167 $ (669) $ 238,697 $ (789)

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
Stockholders' Equity (Tables)	Jun. 30, 2024
Equity [Abstract]
Schedule of Repurchase Activity	The following table presents the repurchase activity from January 1, 2023 through May 5, 2023, the end date of the Repurchase Program: Total number of shares purchased Average price paid per share Approximate dollar value of shares purchased First Quarter 2023 1,589,424 $ 24.19 $ 38,456 Second Quarter 2023 534,790 21.59 11,544 Total 2,124,214 $ 50,000

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	6 Months Ended
Equity Incentive Plans (Tables)	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Schedule of Activity Related to Stock Option Awards	A summary of the activity related to stock option awards during the six months ended June 30, 2024 is as follows: Shares Subject to Options Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding at January 1, 2024 4,225,615 $ 27.36 7.42 $ 5,827 Granted 2,159,889 $ 21.45 Exercised (74,908) $ 15.57 Forfeitures and cancellations (207,690) $ 33.88 Outstanding at June 30, 2024 6,102,906 $ 25.19 7.89 $ 19,526 Exercisable at June 30, 2024 2,636,860 $ 28.98 6.30 $ 8,469
Schedule of Time-based Restricted Stock Units Activity	Number of Restricted Stock Units Weighted-Average Grant Date Fair Value Weighted-Average Remaining Contractual Term (in years) Aggregate Outstanding at January 1, 2024 1,481,572 $ 24.80 0.73 $ 31,735 Granted 786,108 $ 21.45 Released (1,055,959) $ 25.94 Forfeitures and cancellations (7,372) $ 22.18 Outstanding at June 30, 2024 1,204,349 $ 21.63 1.82 $ 30,181 RSU expected to vest at June 30, 2024 1,204,349 $ 21.63 1.82 $ 30,181
Schedule of Weighted Average Assumptions used to Estimate Fair Value	The estimated fair values of stock option awards granted were determined on the date of grant using the Black-Scholes option valuation model with the following weighted-average assumptions: Six Months Ended 2024 2023 Risk-free interest rate 4.0 % 3.7 % Expected volatility 78.3 % 86.1 % Expected dividend yield — % — % Expected term (in years) 6.28 5.75 Weighted-average grant date fair value per share $ 15.28 $ 16.50
Schedule of Non-cash Stock-based Compensation Expense	Total non-cash stock-based compensation expense for all stock awards that was recognized in the consolidated statements of operations and comprehensive loss is as follows: Three Months Ended Six Months Ended (in thousands) 2024 2023 2024 2023 Research and development $ 3,534 $ 2,683 $ 6,988 $ 5,453 General and administrative 4,010 5,744 (1) 10,687 (2) 11,834 (3) Total $ 7,544 $ 8,427 $ 17,675 $ 17,287 (1) Includes $2.9 million related to 2 year RSU initially issued to our new CEO in March 2022 and now fully recognized. (2) Includes $2.6 million related to 2 year RSU initially issued to our new CEO in March 2022 and now fully recognized. (3) Includes $5.8 million related to 2 year RSU initially issued to our new CEO in March 2022 and now fully recognized.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
Commitments and Contingencies (Tables)	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Costs in Cash Flow Statement	The following non-cancellable office lease costs are included in our consolidated statements of cash flow (in thousands): Six Months Ended Leases Classification on the Cash Flow 2024 2023 Operating lease cost Operating $ 1,239 $ 1,239 Cash paid for amounts included in the measurement of lease liabilities Operating 1,217 1,181
Schedule of Future Minimum Annual Obligations	At June 30, 2024, the future minimum annual obligations for the Company’s operating lease liabilities are as follows (in thousands): Years Ending December 31, 2024 $ 1,241 2025 2,531 2026 2,607 2027 2,685 2028 2,766 Thereafter 7,788 Total minimum payments required 19,618 Less imputed interest (2,672) Total $ 16,946

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details)	6 Months Ended
	Jun. 30, 2024 segment
Accounting Policies [Abstract]
Number of reportable segments	1

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Potentially Dilutive Securities (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Options to purchase common stock (in shares)	6,397	4,745	6,768	4,868
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Options to purchase common stock (in shares)	6,148	4,332	6,113	4,443
Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Options to purchase common stock (in shares)	249	413	655	425

Balance Sheet Accounts and Su_3

Balance Sheet Accounts and Supplemental Disclosures - Schedule of Property and Equipment, net (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 8,346	$ 8,316
Less: accumulated depreciation and amortization	(6,513)	(6,218)
Total property and equipment, net	1,833	2,098
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	6,489	6,473
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,654	1,640
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 203	$ 203

Balance Sheet Accounts and Su_4

Balance Sheet Accounts and Supplemental Disclosures -Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Balance Sheet Related Disclosures [Abstract]
Accrued compensation and related expenses	$ 5,421	$ 7,201
Accrued professional fees and other expenses	988	1,412
Accrued research, development and manufacturing expenses	26,815	21,898
Accrued for repurchases of common stock	456	456
Total accrued expenses	$ 33,680	$ 30,967

Collaborative Research and De_3

Collaborative Research and Development Agreements - Narrative (Details) - USD ($)			1 Months Ended		3 Months Ended		6 Months Ended
	Nov. 24, 2023	Oct. 23, 2020	Dec. 31, 2023	Mar. 31, 2014	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregation of Revenue [Line Items]
Collaboration revenue					$ 10,971,000	$ 3,460,000	$ 18,150,000	$ 4,834,000
GSK \| GlaxoSmithKline Collaboration
Disaggregation of Revenue [Line Items]
Agreement term following first commercial sale or expiration of the last to expire patent		12 years
GSK \| GlaxoSmithKline Collaboration \| Minimum
Disaggregation of Revenue [Line Items]
Royalty percent on net sales				4%
GSK \| GlaxoSmithKline Collaboration \| Maximum
Disaggregation of Revenue [Line Items]
Royalty percent on net sales				8%
GSK \| Royalties
Disaggregation of Revenue [Line Items]
Collaboration revenue					11,000,000	3,500,000	18,200,000	4,800,000
GSK \| Royalty Agreement, Up To $1.0 billion \| Anti-PD-1 (Jemperli/Dostarlimab)
Disaggregation of Revenue [Line Items]
Royalty percent on net sales		8%
Net sales royalty		$ 1,000,000,000
GSK \| Royalty Agreement, Above $1.0 billion \| Minimum \| Anti-PD-1 (Jemperli/Dostarlimab)
Disaggregation of Revenue [Line Items]
Royalty percent on net sales		12%
GSK \| Royalty Agreement, Above $1.0 billion \| Maximum \| Anti-PD-1 (Jemperli/Dostarlimab)
Disaggregation of Revenue [Line Items]
Royalty percent on net sales		25%
Net sales royalty		$ 1,000,000,000
GSK \| Jemperli Royalty Monetization Agreement
Disaggregation of Revenue [Line Items]
Collaboration revenue					10,100,000	2,800,000	16,300,000	3,300,000
GSK \| Zejula Royalty Monetization Agreement
Disaggregation of Revenue [Line Items]
Collaboration revenue					900,000	700,000	1,900,000	1,500,000
GSK \| Zejula revenue prior to the Zejula Royalty Monetization Agreement
Disaggregation of Revenue [Line Items]
Collaboration revenue						$ 700,000		$ 1,500,000
Centessa Pharmaceuticals (UK) Limited (Centessa) \| GlaxoSmithKline Collaboration
Disaggregation of Revenue [Line Items]
Potential future payments	$ 10,000,000				$ 10,000,000		$ 10,000,000
Centessa Pharmaceuticals (UK) Limited (Centessa) \| GlaxoSmithKline Collaboration \| License Agreement, Centessa Pharmaceuticals (UK) Limited
Disaggregation of Revenue [Line Items]
Cash payment	4,000,000
Reimbursement	3,000,000
Transaction costs incurred	$ 300,000
Total transferred			$ 7,300,000

Collaborative Research and De_4

Collaborative Research and Development Agreements - Schedule of Milestone Achieved (Details) - USD ($) $ in Thousands

3 Months Ended

6 Months Ended

Jun. 30, 2024

Jun. 30, 2023

Dec. 31, 2022

Sep. 30, 2021

Jun. 30, 2021

Mar. 31, 2021

Mar. 31, 2020

Jun. 30, 2019

Sep. 30, 2018

Dec. 31, 2017

Jun. 30, 2017

Jun. 30, 2016

Mar. 31, 2016

Dec. 31, 2015

Jun. 30, 2015

Jun. 30, 2024

Jun. 30, 2023

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 10,971

$ 3,460

$ 18,150

$ 4,834

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Initiated in vivo toxicology studies using good laboratory practices (GLPs)

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 1,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | IND clearance from the FDA

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 4,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Phase 2 clinical trial initiation

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 3,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Phase 3 clinical trial initiation - first indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 5,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Phase 3 clinical trial initiation - second indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 5,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Filing of the first BLA - first indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 10,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Filing of the first MAA - first indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 5,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Filing of the first BLA - second indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 10,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | First BLA approval - first indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 20,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | First MAA approval - first indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 10,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | First BLA approval - second indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 20,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Filing of the first MAA - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

5,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | First MAA approval - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

10,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | First commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

15,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Second commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

25,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Third commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

50,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Fourth commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

75,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Milestones recognized through June 30, 2024

Disaggregation of Revenue [Line Items]

Collaboration revenue

93,000

GSK | Anti-PD-1 (Jemperli/Dostarlimab) | Milestones that may be recognized in the future

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

180,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Initiated in vivo toxicology studies using good laboratory practices (GLPs)

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 1,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | IND clearance from the FDA

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 4,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Phase 2 clinical trial initiation

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 3,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Phase 3 clinical trial initiation - first indication

Disaggregation of Revenue [Line Items]

Collaboration revenue

$ 5,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Phase 3 clinical trial initiation - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

5,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first BLA - first indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

10,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first MAA - first indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

5,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first BLA - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

10,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First BLA approval - first indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

20,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First MAA approval - first indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

10,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First BLA approval - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

20,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first MAA - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

5,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First MAA approval - second indication

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

10,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

15,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Second commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

25,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Third commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

50,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Fourth commercial sales milestone

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

75,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Milestones recognized through June 30, 2024

Disaggregation of Revenue [Line Items]

Collaboration revenue

13,000

GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Milestones that may be recognized in the future

Disaggregation of Revenue [Line Items]

Milestones that may be recognized in the future

$ 260,000

Sale of Future Royalties - Narr

Sale of Future Royalties - Narrative (Details) - USD ($)	1 Months Ended			3 Months Ended		6 Months Ended
Sale of Future Royalties - Narrative (Details) - USD ($)	May 31, 2024	Sep. 30, 2022	Oct. 31, 2021	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Jan. 01, 2021
Liabilities Related To Sale Of Future Royalties [Line Items]
Collaboration revenue				$ 10,971,000	$ 3,460,000	$ 18,150,000	$ 4,834,000
Liability related to sale of future royalties				361,981,000		361,981,000		$ 310,807,000
Non-cash interest expense				$ 10,953,000	4,358,000	17,270,000	8,694,000
Jemperli Royalty Monetization Agreement
Liabilities Related To Sale Of Future Royalties [Line Items]
Issuance costs related to the sale of future royalties						$ 103,000
Net of proceeds			$ 299,500,000
Effective interest rate				17.20%		17.20%
Non-cash interest expense and amortization of issuance costs				$ 10,700,000	4,200,000	$ 16,800,000	8,100,000
Non-cash interest expense						16,801,000
Jemperli Royalty Monetization Agreement \| Sagard
Liabilities Related To Sale Of Future Royalties [Line Items]
Proceeds from sale of future royalties			250,000,000
Royalties agreement, maximum annual royalty payout capacity			1,000,000,000
Royalties and milestones received				24,500,000		24,500,000
Issuance costs related to the sale of future royalties			400,000
Jemperli Royalty Monetization Agreement \| Sagard \| By the end of 2026
Liabilities Related To Sale Of Future Royalties [Line Items]
Royalties and milestones, agreement amount to be received			600,000,000
Jemperli Royalty Monetization Agreement \| Sagard \| During 2027
Liabilities Related To Sale Of Future Royalties [Line Items]
Royalties and milestones, agreement amount to be received			$ 675,000,000
Jemperli Royalty Monetization Agreement \| GSK
Liabilities Related To Sale Of Future Royalties [Line Items]
Collaboration revenue				10,100,000	2,800,000	16,300,000	3,300,000
Zejula Royalty Monetization Agreement
Liabilities Related To Sale Of Future Royalties [Line Items]
Issuance costs related to the sale of future royalties		$ 200,000
Net of proceeds		34,800,000
Non-cash interest expense						426,000
Zejula Royalty Monetization Agreement \| GSK
Liabilities Related To Sale Of Future Royalties [Line Items]
Collaboration revenue				900,000	700,000	1,900,000	1,500,000
Settlement agreement rate									0.50%
Non-cash interest expense				$ 200,000	$ 200,000	$ 400,000	$ 600,000
Zejula Royalty Monetization Agreement \| DRI Healthcare Trust
Liabilities Related To Sale Of Future Royalties [Line Items]
Proceeds from sale of future royalties		35,000,000
Royalties and milestones, agreement amount to be received		10,000,000
Liability related to sale of future royalties		$ 35,000,000
Jemperli Royalty Monetization Agreement Amendment 1 \| Sagard
Liabilities Related To Sale Of Future Royalties [Line Items]
Proceeds from sale of future royalties	$ 50,000,000
Issuance costs related to the sale of future royalties	$ 100,000

Sale of Future Royalties - Sche

Sale of Future Royalties - Schedule of Royalty Transaction Activity (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Sep. 30, 2022	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Liabilities Related To Sale Of Future Royalties [Roll Forward]
Royalty and milestone payments to Sagard				$ (15,993)	$ (3,071)
Non-cash interest expense recognized		$ 10,953	$ 4,358	17,270	$ 8,694
Jemperli Royalty Monetization Agreement
Liabilities Related To Sale Of Future Royalties [Roll Forward]
Beginning balance				278,090
Proceeds from sale of future royalties				50,000
Issuance costs related to the sale of future royalties				(103)
Amortization of issuance costs				28
Royalty and milestone payments to Sagard				(14,099)
Non-cash interest expense recognized				16,801
Ending balance		330,717		330,717
Zejula Royalty Monetization Agreement
Liabilities Related To Sale Of Future Royalties [Roll Forward]
Beginning balance				32,717
Issuance costs related to the sale of future royalties	$ (200)
Amortization of issuance costs				15
Royalty and milestone payments to Sagard				(1,894)
Non-cash interest expense recognized				426
Ending balance		$ 31,264		$ 31,264

Fair Value Measurements and A_3

Fair Value Measurements and Available for Sale Investments -Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	$ 321,629	$ 381,965
U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	296,797	325,714
Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities		244
Agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	5,066	20,253
Commercial and corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	19,766	35,754
Recurring \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	59,280	27,789
Recurring \| Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	2,737	6,286
Recurring \| U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	296,797	325,714
Recurring \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities		244
Recurring \| Agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	5,066	20,253
Recurring \| Commercial and corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	19,766	35,754
Recurring \| Quoted Market Prices for Identical Assets (Level 1) \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	59,280	27,789
Recurring \| Quoted Market Prices for Identical Assets (Level 1) \| Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	2,737	6,286
Recurring \| Quoted Market Prices for Identical Assets (Level 1) \| U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	296,797	325,714
Recurring \| Quoted Market Prices for Identical Assets (Level 1) \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities		0
Recurring \| Quoted Market Prices for Identical Assets (Level 1) \| Agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	0	0
Recurring \| Quoted Market Prices for Identical Assets (Level 1) \| Commercial and corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities		244
Recurring \| Significant Other Observable Inputs (Level 2) \| Agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	5,066	20,253
Recurring \| Significant Other Observable Inputs (Level 2) \| Commercial and corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	19,766	35,754
Recurring \| Significant Unobservable Inputs (Level 3) \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities		0
Recurring \| Significant Unobservable Inputs (Level 3) \| Agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Commercial and corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, debt securities	$ 0	$ 0

Fair Value Measurements and A_4

Fair Value Measurements and Available for Sale Investments -Schedule of Available-for-sale Investments (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 321,837	$ 382,555
Gross Unrealized Gains	27	199
Gross Unrealized Losses	(235)	(789)
Total Fair Value	321,629	381,965
Short-term investments	278,983	354,939
Long-term investments	42,646	27,026
Agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,074	20,322
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(8)	(69)
Total Fair Value	5,066	20,253
Short-term investments	5,100	20,300
Long-term investments	$ 0	$ 0
Agency securities \| Minimum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)	1 year	1 year
Agency securities \| Maximum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)	2 years	2 years
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		$ 246
Gross Unrealized Gains		0
Gross Unrealized Losses		(2)
Total Fair Value		244
Short-term investments		200
Long-term investments		$ 0
Certificates of deposit \| Minimum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)		1 year
Certificates of deposit \| Maximum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)		2 years
Commercial and corporate obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 19,778	$ 35,760
Gross Unrealized Gains	0	77
Gross Unrealized Losses	(12)	(83)
Total Fair Value	19,766	35,754
Short-term investments	19,800	25,800
Long-term investments	$ 0	$ 10,000
Commercial and corporate obligations \| Minimum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)	1 year	1 year
Commercial and corporate obligations \| Maximum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)	2 years	2 years
U.S. Treasury Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 296,985	$ 326,227
Gross Unrealized Gains	27	122
Gross Unrealized Losses	(215)	(635)
Total Fair Value	296,797	325,714
Short-term investments	254,200	308,600
Long-term investments	$ 42,600	$ 17,100
U.S. Treasury Securities \| Minimum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)	1 year	1 year
U.S. Treasury Securities \| Maximum
Debt Securities, Available-for-sale [Line Items]
Remaining maturity (in years)	2 years	2 years

Fair Value Measurements and A_5

Fair Value Measurements and Available for Sale Investments - Schedule of Unrealized Loss and Fair Values in a Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair value	$ 196,718	$ 106,530
Less than 12 months, Gross unrealized losses	(129)	(120)
12 months or greater, Fair value	61,271	132,167
12 months or greater, Gross unrealized losses	(106)	(669)
Fair Value	257,989	238,697
Gross Unrealized Losses	(235)	(789)
Agency securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair value	0	2,530
Less than 12 months, Gross unrealized losses	0	(1)
12 months or greater, Fair value	5,066	17,723
12 months or greater, Gross unrealized losses	(8)	(68)
Fair Value	5,066	20,253
Gross Unrealized Losses	(8)	(69)
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair value		0
Less than 12 months, Gross unrealized losses		0
12 months or greater, Fair value		244
12 months or greater, Gross unrealized losses		(2)
Fair Value		244
Gross Unrealized Losses		(2)
Commercial and corporate obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair value	14,258	5,160
Less than 12 months, Gross unrealized losses	(10)	(9)
12 months or greater, Fair value	3,804	15,200
12 months or greater, Gross unrealized losses	(2)	(74)
Fair Value	18,062	20,360
Gross Unrealized Losses	(12)	(83)
U.S. Treasury Securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair value	182,460	98,840
Less than 12 months, Gross unrealized losses	(119)	(110)
12 months or greater, Fair value	52,401	99,000
12 months or greater, Gross unrealized losses	(96)	(525)
Fair Value	234,861	197,840
Gross Unrealized Losses	$ (215)	$ (635)

Fair Value Measurements and A_6

Fair Value Measurements and Available for Sale Investments - Narratives (Details) - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Unrealized losses on available-for-sale	$ 235,000	$ 789,000
Unrealized losses on available for sale investments in unrealized loss position for greater than 12 months	106,000	$ 669,000
Allowance for credit losses	$ 0

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) - USD ($)	6 Months Ended
Stockholders' Equity - Narrative (Details) - USD ($)	Jun. 30, 2024	Dec. 31, 2023	Jan. 31, 2023	Nov. 30, 2022
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	27,434,033	26,597,000
Common stock, shares outstanding (in shares)	27,434,033	26,597,000
Authorized repurchase amount			$ 50,000,000
Stock repurchase plan, common stock par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Open Market Sales Agreement
Class of Stock [Line Items]
Aggregate offering of (up to)				$ 150,000,000
Shares sold (in shares)	0

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule Of Stock Repurchase Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024
Equity [Abstract]
Total number of shares purchased (in shares)	534,790	1,589,424	2,124,214
Average price paid per share (in dollars per share)	$ 21.59	$ 24.19
Approximate dollar value of shares purchased (in dollars per share)	$ 11,544	$ 38,456	$ 50,000

Equity Incentive Plans - Narrat

Equity Incentive Plans - Narrative (Details) $ in Millions				6 Months Ended
Equity Incentive Plans - Narrative (Details) $ in Millions	Jun. 12, 2024 shares	Jan. 01, 2024 shares	Jan. 01, 2018	Jun. 30, 2024 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock options exercised \| $				$ 1.1
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $				$ 0.2
Weighted average period remaining for amortization of unrecognized compensation cost (in years)				4 months 17 days
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				4 years
Award expiration period				10 years
Unrecognized compensation cost \| $				$ 51.2
Weighted average period remaining for amortization of unrecognized compensation cost (in years)				3 years 10 days
Stock Options \| Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				1 year
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award equivalent shares				1
Unrecognized compensation cost \| $				$ 22.1
Weighted average period remaining for amortization of unrecognized compensation cost (in years)				3 years 1 month 6 days
Equity Incentive Plan, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual increase in number of shares available for issuance percentage			4%
Capital shares reserved for future issuance, increase (in shares)	2,700,000	1,063,871
Shares reserved for future award grants (in shares)				3,653,227
Employee Stock Purchase Plan, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future award grants (in shares)				1,946,965
Employee Stock Purchase Plan, 2017 \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual increase in number of shares available for issuance percentage			1%
Capital shares reserved for future issuance, increase (in shares)		265,967
Issued under ESPP (in shares)				151,842

Equity Incentive Plans -Schedul

Equity Incentive Plans -Schedule of Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Shares Subject to Options
Stock options outstanding, beginning balance (in shares)	4,225,615
Granted (in shares)	2,159,889
Exercised (in shares)	(74,908)
Forfeitures and cancellations (in shares)	(207,690)
Stock options outstanding, ending balance (in shares)	6,102,906	4,225,615
Shares subject to options, exercisable, ending balance (in shares)	2,636,860
Weighted-Average Exercise Price per Share
Stock options outstanding, beginning balance (in dollars per share)	$ 27.36
Granted (in dollars per share)	21.45
Exercised (in dollars per share)	15.57
Forfeitures and cancellations (in dollars per share)	33.88
Stock options outstanding, ending balance (in dollars per share)	25.19	$ 27.36
Weighted-average exercise price per share, Stock options exercisable, ending balance (in dollars per share)	$ 28.98
Weighted-Average Remaining Contractual Term and Aggregate Intrinsic Value
Weighted average remaining contractual term, options outstanding (in years)	7 years 10 months 20 days	7 years 5 months 1 day
Weighted average remaining contractual term, options exercisable (in years)	6 years 3 months 18 days
Aggregate intrinsic value, options outstanding	$ 19,526	$ 5,827
Aggregate intrinsic value, options exercisable	$ 8,469

Equity Incentive Plans - Schedu

Equity Incentive Plans - Schedule of Time-based Restricted Stock Units (Details) - RSUs - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Number of Restricted Stock Units
Number of shares, beginning balance (in shares)	1,481,572
Granted (in shares)	786,108
Released (in shares)	(1,055,959)
Forfeitures and cancellations (in shares)	(7,372)
Number of shares, ending balance (in shares)	1,204,349	1,481,572
Number of shares, Restricted stock units expected to vest (in shares)	1,204,349
Weighted-Average Grant Date Fair Value
Weighted average grant date fair value, beginning balance (in dollars per share)	$ 24.80
Granted (in dollars per share)	21.45
Vested (in dollars per share)	25.94
Cancelled (in dollars per share)	22.18
Weighted average grant date fair value, ending balance (in dollars per share)	21.63	$ 24.80
Number of shares, Restricted stock units expected to vest (in dollars per share)	$ 21.63
Weighted-Average Remaining Contractual Term and Aggregate Intrinsic Value
Weighted average remaining contractual term, other than options outstanding (in years)	1 year 9 months 25 days	8 months 23 days
Weighted average remaining contractual term, other than options vested and expected to vest (in years)	1 year 9 months 25 days
Aggregate intrinsic value, outstanding	$ 30,181	$ 31,735
Aggregate intrinsic value, restricted stock units expected to vest	$ 30,181

Equity Incentive Plans - Sche_2

Equity Incentive Plans - Schedule of Weighted Average Assumptions used to Estimate Fair Value (Details) - Stock Options - $ / shares	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4%	3.70%
Expected volatility	78.30%	86.10%
Expected dividend yield	0%	0%
Expected term (in years)	6 years 3 months 10 days	5 years 9 months
Weighted average grant date fair value per share (in dollars per share)	$ 15.28	$ 16.50

Equity Incentive Plans -Sched_2

Equity Incentive Plans -Schedule of Allocation of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total	$ 7,544	$ 8,427	$ 17,675	$ 17,287
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total	3,534	2,683	6,988	5,453
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total	$ 4,010	5,744	10,687	11,834
General and administrative \| CEO \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total		$ 2,900	$ 2,600	$ 5,800
Award vesting period		2 years	2 years	2 years

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) ft² in Thousands, $ in Thousands	May 04, 2020 ft² $ / ft²	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Apr. 05, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets		$ 15,291	$ 16,174
Lease liability		$ 16,946
Weighted-average discount rate		4%
Weighted average remaining lease term		7 years 2 months 12 days
Lease Agreement
Lessee, Lease, Description [Line Items]
Area of leased property (sqft) \| ft²	45
Lease term	124 months
Lease renewal term	5 years
Lease termination term	7 years
Monthly base rate (in dollars per sqft) \| $ / ft²	4.20
Increase in annual rent percentage	3%
Operating lease right-of-use assets				$ 20,600
Lease liability				$ 20,700
Security deposit		$ 300

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Costs Included in Cash Flow Statement (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 1,239	$ 1,239
Cash paid for amounts included in the measurement of lease liabilities	$ 1,217	$ 1,181

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Future Minimum Annual Obligations (Details) $ in Thousands	Jun. 30, 2024 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2024	$ 1,241
2025	2,531
2026	2,607
2027	2,685
2028	2,766
Thereafter	7,788
Total minimum payments required	19,618
Less imputed interest	(2,672)
Total	$ 16,946