Deciphera Pharmaceuticals (DCPH) 10-K 7 Feb 24 2023 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2023	Jan. 31, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-38219
Entity Registrant Name	DECIPHERA PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	30-1003521
Entity Address, Address Line One	200 Smith Street
Entity Address, City or Town	Waltham
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02451
City Area Code	781
Local Phone Number	209-6400
Title of 12(b) Security	Common Stock, $0.01 Par Value
Trading Symbol	DCPH
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Smaller Reporting Company	false
Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 777,074,060
Entity Common Stock, Shares Outstanding		80,800,062
Documents Incorporated by Reference	Portions of the registrant's Proxy Statement for its 2024 Annual Meeting of Stockholders, which the registrant intends to file pursuant to Regulation 14A with the Securities and Exchange Commission not later than 120 days after the registrant's fiscal year ended December 31, 2023, are incorporated by reference into Part III of this Annual Report on Form 10-K.
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity Central Index Key	0001654151

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2023
Audit Information [Abstract]
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	238
Auditor Location	Boston, Massachusetts

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 83,507	$ 64,741
Short-term marketable securities	222,709	259,745
Accounts receivable, net	31,952	22,429
Inventory	21,210	20,561
Prepaid expenses and other current assets	21,718	25,482
Total current assets	381,096	392,958
Long-term marketable securities	46,699	14,550
Long-term investments—restricted and other long-term assets	8,277	3,277
Property and equipment, net	5,421	6,707
Operating lease assets	32,073	36,547
Total assets	473,566	454,039
Current liabilities:
Accounts payable	26,476	18,612
Accrued expenses and other current liabilities	70,295	64,622
Operating lease liabilities	3,504	3,235
Total current liabilities	100,275	86,469
Operating lease liabilities, net of current portion	22,375	25,879
Total liabilities	122,650	112,348
Commitments and contingencies (Note 16)
Stockholders' equity:
Preferred stock, $0.01 par value per share; 5,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.01 par value per share; 125,000,000 shares authorized; 80,503,338 shares and 67,637,351 shares issued and outstanding as of December 31, 2023 and 2022, respectively	805	676
Additional paid-in capital	1,777,839	1,575,361
Accumulated other comprehensive income	577	(983)
Accumulated deficit	(1,428,305)	(1,233,363)
Total stockholders' equity	350,916	341,691
Total liabilities and stockholders' equity	$ 473,566	$ 454,039

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0
Preferred stock, shares issued (in shares)	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	125,000,000	125,000,000
Common stock, shares issued (in shares)	80,503,338	67,637,351
Common stock, shares outstanding (in shares)	80,503,338	67,637,351

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Total revenues	$ 163,356	$ 134,036	$ 96,148
Cost and operating expenses:
Cost of sales	3,732	8,770	2,932
Research and development	234,123	187,821	257,040
Selling, general, and administrative	136,459	120,167	136,253
Total cost and operating expenses	374,314	316,758	396,225
Loss from operations	(210,958)	(182,722)	(300,077)
Other income (expense):
Interest and other income, net	16,447	4,513	113
Total other income (expense), net	16,447	4,513	113
Loss before income tax expense	(194,511)	(178,209)	(299,964)
Income tax expense	431	722	0
Net loss	$ (194,942)	$ (178,931)	$ (299,964)
Net loss per share - basic (in dollars per share)	$ (2.29)	$ (2.37)	$ (5.16)
Net loss per share - diluted (in dollars per share)	$ (2.29)	$ (2.37)	$ (5.16)
Weighted average common shares outstanding - basic (in shares)	85,059,962	75,500,148	58,084,325
Weighted average common shares outstanding - diluted (in shares)	85,059,962	75,500,148	58,084,325
Comprehensive loss:
Net loss	$ (194,942)	$ (178,931)	$ (299,964)
Other comprehensive income (loss):
Unrealized gains (losses) on marketable securities	1,043	(992)	(278)
Currency translation adjustment	517	(42)	318
Total other comprehensive income (loss)	1,560	(1,034)	40
Total comprehensive loss	$ (193,382)	$ (179,965)	$ (299,924)

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Warrant
Beginning balance (in shares) at Dec. 31, 2020		57,596,144
Beginning balance at Dec. 31, 2020	$ 543,676	$ 576	$ 1,297,557	$ 11	$ (754,468)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)		172,094
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs	8,549	$ 2	8,547
Issuance of common stock under stock option and incentive and employee stock purchase plans (in shares)		781,406
Issuance of common stock under stock option and incentive and employee stock purchase plans	6,341	$ 7	6,334
Stock-based compensation expense	46,078		46,078
Other Comprehensive Income (Loss)	40			40
Net loss	(299,964)				(299,964)
Ending balance (in shares) at Dec. 31, 2021		58,549,644
Ending balance at Dec. 31, 2021	304,720	$ 585	1,358,516	51	(1,054,432)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)		7,501,239				892,798
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs	163,353	$ 75	163,278			$ 9
Issuance of common stock under stock option and incentive and employee stock purchase plans (in shares)		693,670
Issuance of common stock under stock option and incentive and employee stock purchase plans	1,632	$ 7	1,625
Stock-based compensation expense	51,942		51,942
Other Comprehensive Income (Loss)	(1,034)			(1,034)
Net loss	$ (178,931)				(178,931)
Ending balance (in shares) at Dec. 31, 2022	67,637,351	67,637,351
Ending balance at Dec. 31, 2022	$ 341,691	$ 676	1,575,361	(983)	(1,233,363)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)		8,990,296				2,427,693
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs	149,113	$ 90	149,023			$ 24
Issuance of common stock under stock option and incentive and employee stock purchase plans (in shares)		1,447,998
Issuance of common stock under stock option and incentive and employee stock purchase plans	2,867	$ 15	2,852
Stock-based compensation expense	50,603		50,603
Other Comprehensive Income (Loss)	1,560			1,560
Net loss	$ (194,942)				(194,942)
Ending balance (in shares) at Dec. 31, 2023	80,503,338	80,503,338
Ending balance at Dec. 31, 2023	$ 350,916	$ 805	$ 1,777,839	$ 577	$ (1,428,305)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (194,942,000)	$ (178,931,000)	$ (299,964,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	50,603,000	51,942,000	46,078,000
Depreciation expense	2,100,000	2,946,000	3,014,000
Noncash lease expense	4,475,000	4,126,000	3,446,000
Acquired in-process research and development	0	0	4,000,000
Net amortization (accretion) of premiums (discounts) on marketable securities	(7,397,000)	(1,297,000)	1,782,000
Changes in operating assets and liabilities:
Accounts receivable	(9,345,000)	(1,784,000)	(6,699,000)
Inventory	(386,000)	(7,109,000)	(10,155,000)
Prepaid expenses and other current assets	3,808,000	(9,510,000)	(7,934,000)
Other long-term assets	(4,996,000)	(168,000)	0
Accounts payable	7,777,000	5,319,000	833,000
Accrued expenses and other current liabilities	4,411,000	(16,184,000)	27,285,000
Income tax liabilities	431,000	722,000	0
Operating lease liabilities	(3,236,000)	(2,934,000)	(2,510,000)
Net cash flows used in operating activities	(146,697,000)	(152,862,000)	(240,824,000)
Cash flows from investing activities:
Purchases of marketable securities	(322,572,000)	(322,767,000)	(335,375,000)
Maturities of marketable securities	335,114,000	289,299,000	468,587,000
Sales of marketable securities	785,000	0	49,613,000
Purchases of property and equipment	(778,000)	(841,000)	(1,970,000)
Acquired in-process research and development	0	0	(4,000,000)
Increase in restricted investments	0	0	(7,000)
Net cash flows provided by (used in) investing activities	12,549,000	(34,309,000)	176,848,000
Cash flows from financing activities:
Proceeds from offerings of common stock, net of underwriting discounts and commissions	149,747,000	163,778,000	8,589,000
Proceeds from pre-funded warrants	24,000	9,000	0
Payments of public offering costs	(634,000)	(425,000)	(40,000)
Proceeds from stock option exercises and employee stock purchase plan	2,867,000	1,632,000	6,341,000
Net cash flows provided by financing activities	152,004,000	164,994,000	14,890,000
Net (decrease) increase in cash and cash equivalents	17,856,000	(22,177,000)	(49,086,000)
Effect of exchange rate changes on cash and cash equivalents	910,000	(145,000)	252,000
Cash and cash equivalents at beginning of period	64,741,000	87,063,000	135,897,000
Cash and cash equivalents at end of period	$ 83,507,000	$ 64,741,000	$ 87,063,000

Nature of the Business and Basi

Nature of the Business and Basis of Presentation	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business and Basis of Presentation	Nature of the Business and Basis of Presentation Nature of the Business Deciphera Pharmaceuticals, Inc. (the Company) is a biopharmaceutical company focused on discovering, developing, and commercializing important new medicines to improve the lives of people with cancer. Leveraging its proprietary switch-control inhibitor platform and deep expertise in kinase biology, the Company designs kinase inhibitors to target the switch pocket region of the kinase with the goal of developing potentially transformative medicines. Through its patient-inspired approach, the Company seeks to develop a broad portfolio of innovative medicines to improve treatment outcomes. QINLOCK, the Company's switch-control tyrosine kinase inhibitor, was discovered using its proprietary drug discovery platform and designed for the treatment of gastrointestinal stromal tumor (GIST). QINLOCK is approved in Australia, Canada, China, the European Union (EU), Hong Kong, Iceland, Israel, Liechtenstein, Macau, Norway, New Zealand, Singapore, Switzerland, Taiwan, the United Kingdom (U.K.), and the United States (U.S.) for the treatment of fourth-line GIST. The Company wholly owns QINLOCK and all of its drug candidates with the exception of a development and commercialization out-license agreement for QINLOCK in Greater China. In addition to QINLOCK, the Company has developed a robust pipeline of novel drug candidates using its switch-control kinase inhibitor platform, including vimseltinib and DCC-3116. The Company is subject to risks and uncertainties common to companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, market acceptance and the successful commercialization of QINLOCK or any of the Company's current or future drug candidates for which it receives marketing approval, protection of proprietary technology, ability to complete late-stage clinical trials, ability to obtain and maintain regulatory approvals, compliance with government regulations, and the ability to secure additional capital to fund operations. QINLOCK and the Company's drug candidates currently under development will require significant additional research and development efforts, including extensive preclinical and/or clinical testing and regulatory approval. In addition to supporting its research and development efforts, the Company will be required to invest in the Company's commercial capabilities and infrastructure, to support its commercialization of QINLOCK, the Company's first approved drug, and any current or future drug candidate for which the Company obtains marketing approval. These efforts require significant amounts of additional capital, adequate personnel and infrastructure, and extensive compliance-reporting capabilities. Even if the Company's drug development and commercialization efforts are successful, it is uncertain when, if ever, the Company will realize sufficient revenue to result in a profit from product sales of QINLOCK or any current or future drug candidates for which it receives marketing approval. In April 2022, the Company entered into an underwriting agreement with J.P. Morgan Securities LLC and Jefferies, LLC (Jefferies), as representatives of the several underwriters named therein, relating to the issuance and sale of an aggregate of 7,501,239 shares of its common stock at a public offering price of $10.00 per share to certain investors. In addition, the Company issued and sold pre-funded warrants to purchase 9,748,761 shares of its common stock at a public offering price of $9.99 per pre-funded warrant, which equals the public offering price per share of the common stock less the $0.01 exercise price per share of each pre-funded warrant. The offering closed on April 29, 2022, resulting in net proceeds of $163.4 million, after deducting underwriting discounts and commissions and other offering expenses. As the pre-funded warrants are indexed to the Company’s common stock (and otherwise meet the requirements to be classified in equity), the Company recorded the consideration received from the issuance of the pre-funded warrants as additional paid-in capital on the Company’s consolidated balance sheets. The pre-funded warrants are exercisable at any time. Certain holders of pre-funded warrants may not exercise the pre-funded warrant if the holder, together with its affiliates, would beneficially own more than 4.99%, 9.99% or 28.22% of the number of shares of the Company’s common stock outstanding immediately after giving effect to such exercise. A holder of pre-funded warrants may increase or decrease this percentage not in excess of 19.99%, with the exception of one holder, by providing at least 61 days’ prior notice to the Company. During the years ended December 31, 2023 and 2022, 2,427,693 and 892,798 shares of pre-funded warrants were exercised, respectively, resulting in net proceeds of less than $0.1 million in each year. As of December 31, 2023, there were 6,428,270 pre-funded warrants outstanding. In August 2022, the Company entered into an amendment to its existing Open Market Sale Agreement℠ (the August 2020 Sales Agreement and as amended, Amended Sales Agreement) with Jefferies, pursuant to which the Company may issue and sell shares of its common stock having aggregate offering proceeds of up to $200.0 million from time to time through Jefferies as its sales agent. Upon delivery of a placement notice and subject to the terms and conditions of the Amended Sales Agreement, Jefferies may sell the Shares by any method permitted by law deemed to be an "at the market offering" as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended. The Company may sell the Shares in amounts and at times to be determined by the Company from time to time subject to the terms and conditions of the Amended Sales Agreement, but it has no obligation to sell any Shares under the Amended Sales Agreement. The Company or Jefferies may suspend or terminate the offering of Shares upon notice to the other party and subject to other conditions. During the year ended December 31, 2021, the Company issued 172,094 shares resulting in net proceeds of $8.5 million after deducting commissions and other offering expenses, under the August 2020 Sales Agreement. During the years ended, December 31, 2023 and 2022, the Company did not issue any shares under the August 2020 Sales Agreement or the Amended Sales Agreement. On January 18, 2023, the Company delivered written notice to Jefferies that it was suspending and terminating the prospectus related to the common stock issuable pursuant to the terms of the Amended Sales Agreement. As a result, the Company will not make any sales of its securities pursuant to the Amended Sales Agreement, unless and until a new prospectus, prospectus supplement, or a new registration statement is filed. The Amended Sales Agreement was superseded by an Open Market Sale Agreement SM entered into in May 2023 (the May 2023 Sales Agreement) with Jefferies. In January 2023, the Company entered into an underwriting agreement with J.P. Morgan Securities LLC, Jefferies, Cowen and Company, LLC, and Guggenheim Securities, LLC, as representatives of the several underwriters named therein, relating to the issuance and sale of an aggregate of 7,986,111 shares of its common stock at a public offering price of $18.00 per share. The offering closed on January 24, 2023, resulting in net proceeds of $134.5 million, after deducting underwriting discounts and commissions and other offering expenses. In May 2023, the Company entered into the May 2023 Sales Agreement with Jefferies, pursuant to which the Company may issue and sell the Shares having aggregate offering proceeds of up to $200.0 million from time to time through Jefferies as its sales agent. Upon delivery of a placement notice and subject to the terms and conditions of the May 2023 Sales Agreement, Jefferies may sell the Shares by any method permitted by law deemed to be an "at the market offering" as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended. The Company may sell the Shares in amounts and at times to be determined by the Company from time to time subject to the terms and conditions of the May 2023 Sales Agreement, but it has no obligation to sell any Shares under the May 2023 Sales Agreement. The Company or Jefferies may suspend or terminate the offering of Shares upon notice to the other party and subject to other conditions. During the year ended December 31, 2023, the Company issued 1,004,185 shares resulting in net proceeds of $14.6 million, after deducting commissions and other offering expenses, under the May 2023 Sales Agreement. As of December 31, 2023, there was up to $185.0 million available for future issuance under the May 2023 Sales Agreement. Basis of Presentation The accompanying consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. Since inception, the Company has incurred recurring losses including net losses of $194.9 million, $178.9 million, and $300.0 million for the years ended December 31, 2023, 2022, and 2021, respectively. As of December 31, 2023, the Company had an accumulated deficit of $1.4 billion. The Company expects to continue to generate operating losses for the foreseeable future. The Company expects that its cash, cash equivalents, and marketable securities of $352.9 million as of December 31, 2023, together with anticipated product, royalty, and supply revenues, but excluding any potential future milestones received under its collaboration or license agreements will be sufficient to fund its operating expenses and capital expenditure requirements through at least 12 months from the issuance date of these consolidated financial statements. The future viability of the Company is dependent on its ability to raise additional capital to fund its operations. The Company will need to obtain substantial additional funding in connection with continuing operations. If the Company is unable to raise capital when needed, or on attractive terms, it could be forced to delay, reduce, or further terminate its research or drug development programs or certain commercialization efforts. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all. These consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated. These consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (GAAP).

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, product revenue reserves, the accrual for research and development expenses, and the valuation of stock-based option awards. Estimates are periodically reviewed in light of changes in circumstances, facts, and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates. Segment Information The Company manages its operations, and the Company's chief operating decision maker views the Company's business, as a single segment for the purposes of making decisions on how to allocate resources and assessing performance. The Company's focus is discovering, developing, and commercializing important new medicines to improve the lives of people with cancer by leveraging its proprietary switch-control inhibitor platform and deep expertise in kinase biology. The Company designs kinase inhibitors to target the switch pocket region of the kinase with the goal of developing potentially transformative medicines and develop a broad portfolio of innovative medicines to improve treatment outcomes. The Company operates in the U.S. and Europe. Primarily all of the Company's long-lived assets reside in the U.S. Revenues The Company recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. Product Revenues QINLOCK is approved in Australia, Canada, China, the EU, Hong Kong, Iceland, Israel, Liechtenstein, Macau, Norway, New Zealand, Singapore, Switzerland, Taiwan, the U.S. and the U.K. for the treatment of fourth-line GIST. The Company recognizes product revenues, net of variable consideration related to certain allowances and accruals, when the customer takes control of the product, which is typically upon delivery to the customer. Product revenue is recorded at the net sales price, or transaction price. The Company records product revenue reserves, which are classified as a reduction in product revenues, to account for the components of variable consideration. Variable consideration includes the following components: chargebacks, government rebates, trade discounts and allowances, product returns, and other incentives, which are described below. These reserves are based on estimates of the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable (if the amount is payable to the Company's customer) or a liability (if the amount is payable to a party other than the Company's customer, other than product returns, which are recorded as liabilities). The Company's estimates of reserves established for variable consideration are calculated based upon a consistent application of the expected value method, which is the sum of probability-weighted amounts in a range of possible consideration amounts. These estimates reflect the Company's historical experience, current contractual and statutory requirements, specific known market events and trends, industry data, forecasted customer buying, and payment patterns. The amount of variable consideration that is included in the transaction price may be subject to constraint and is included in net product revenues only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration received may ultimately differ from the Company's estimates. If actual results vary, the Company adjusts these estimates, which could have an effect on earnings in the period of adjustment. Chargebacks and administrative fees: Chargebacks for discounts represent the Company's estimated obligations resulting from contractual commitments to sell product to qualified healthcare providers and government agencies at prices lower than the list prices charged to the customers who directly purchase the product from the Company. The customers charge the Company for the difference between what the customers pay the Company for the product and the customer's ultimate contractually committed or government required lower selling price to the qualified healthcare providers. As part of the Company's contractual commitments to sell product to qualified healthcare providers, the Company pays fees for administrative services, such as account management and data reporting. Government rebates: Government rebates consist of Medicare, Tricare, Medicaid, and other governmental rebates in the U.S. and other similar programs in other countries, including countries in which the Company is accruing for estimated rebates because final pricing has not yet been negotiated. These reserves are recorded in the same period the related revenue is recognized. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom it will owe a rebate under the Medicare Part D program. Trade discounts and allowances: The Company provides the customers with discounts that are explicitly stated in the contracts and recorded in the period the related product revenue is recognized. In addition, the Company also receives sales order management, inventory management, and data services from the customers in exchange for certain fees. Product returns: The Company estimates the amount of its product sales that may be returned by its customers and records this estimate in the period the related product revenue is recognized. The Company currently estimates product return liabilities based on available industry data and its visibility into the inventory remaining in the distribution channel. Other incentives: Other incentives include co-payment assistance provided to qualified patients, whereby the Company may provide financial assistance to patients with prescription drug co-payments required by the patient's insurance provider. Reserves for co-payment assistance are recorded in the same period the related revenue is recognized. Collaboration Revenues In June 2019, the Company entered into a License Agreement (the Zai License Agreement) with an affiliate of Zai Lab (Shanghai) Co., Ltd. (Zai), pursuant to which the Company granted Zai exclusive rights to develop and commercialize QINLOCK, including certain follow-on compounds (the Licensed Products), in Greater China (the Territory). In February 2020, the Company entered into a Supply Agreement (the Zai Supply Agreement), as required by terms in the Zai License Agreement, pursuant to which the Company supplies the Licensed Products to Zai for use in the Territory for commercial inventory and clinical trials. Subject to the Zai Supply Agreement, costs incurred by the Company for external manufacturing services are reimbursed by Zai. The Zai License Agreement includes development and regulatory milestone payments. Therefore, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant cumulative revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company's control or the licensee's control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. The Zai License Agreement also includes sales-based royalties for the license of intellectual property, including milestone payments based on the level of sales. As the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied. The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time, and if over time, recognition is based on the use of an output or input method. For additional information on the Zai License Agreement and Zai Supply Agreement, please read Note 3, Revenues , to these consolidated financial statements. Cash Equivalents The Company considers all highly liquid investments with original maturities of 90 days or less at the date of purchase to be cash equivalents. Marketable Securities Marketable securities consist of investments with original maturities greater than 90 days at the date of purchase. As of December 31, 2023 and 2022, the Company's marketable securities were comprised of debt securities, commercial paper, U.S. government securities and the Company considers its marketable securities portfolio to be available-for-sale. Available-for-sale marketable securities are classified as current or non-current based on each instrument's underlying effective maturity date and for which the Company has the intent and ability to hold the investment for a period of greater than 12 months. Marketable securities with maturities of less than 12 months from the balance sheet date are classified as current and are included in short-term marketable securities in the consolidated balance sheets. Marketable securities with maturities greater than 12 months from the balance sheet date for which we have the intent and ability to hold the investment for greater than 12 months are classified as non-current and are included in long-term marketable securities in the consolidated balance sheets. Available-for-sale marketable debt securities are recorded at fair market value and unrealized gains and losses are included in accumulated other comprehensive income (loss) in equity, net of related tax effects, except for the changes in allowance for expected credit losses, which are recorded in other income (expense), net, within the consolidated statements of operations and comprehensive loss. Realized gains and losses are reported in other income (expense), net, within the consolidated statements of operations and comprehensive loss on a specific identification basis. The Company conducts periodic reviews to identify and evaluate each investment in the Company's portfolio that has an unrealized loss to determine whether a credit loss exists. An unrealized loss exists when the current fair value of an individual security is less than its amortized cost basis. A credit loss is estimated by considering available information relevant to the collectability of the security and information about past events, current conditions, and reasonable and supportable forecasts. Any credit loss is recorded as a charge to other income (expense), net, not to exceed the amount of the unrealized loss. Unrealized losses other than the credit loss are recognized in accumulated other comprehensive income (loss). When determining whether a credit loss exists, the Company considers several factors, including whether the Company has the intent to sell the security or whether it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis. If the Company has an intent to sell, or if it is more likely than not that the Company will be required to sell a debt security in an unrealized loss position before recovery of its amortized cost basis, the Company will write down the security to its fair value and record the corresponding charge as a component of other income (expense), net. No declines in value were deemed to be credit losses during the years ended December 31, 2023, 2022 or 2021. Fair Value Measurements Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies, and similar techniques. The Company's cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy described above. For additional information on the Company's fair value hierarchy, please read Note 4, Marketable Securities and Fair Value Measurements , to these consolidated financial statements. The carrying values of the Company's accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. Concentrations of Credit Risk and of Significant Suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company maintains all cash, cash equivalents, and marketable securities at accredited financial institutions, in amounts that exceed federally insured limits. The Company attempts to minimize the risks related to cash, cash equivalents, and marketable securities by investing in a range of financial instruments as defined by the Company. The Company has established guidelines related to credit ratings and maturities intended to safeguard principal balances and maintain liquidity. The marketable securities portfolio is maintained in accordance with the Company's investment policy, which defines allowable investments, specifies credit quality standards and limits the credit exposure of any single issuer. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company is dependent on third-party manufacturers to supply products for commercial and research and development activities associated with its drug and drug candidates, as applicable. In particular, the Company relies and expects to continue to rely on a small number of manufacturers to supply it with its requirements for the active pharmaceutical ingredients and formulated drugs related to the Company's drug and drug candidate activities. These activities, including the commercialization of QINLOCK, could be adversely affected by a significant interruption in the supply of active pharmaceutical ingredients and formulated drugs. Accounts Receivable Accounts receivable arise from product sales and amounts due from the Company's collaboration partner and have standard payment terms that generally require payment within 30 to 90 days. The amount from product sales represents amounts due from specialty distributors and specialty pharmacies, which are recorded net of reserves for customer chargebacks, trade discounts and allowances, and other incentives to the extent such amounts are payable to the customer by the Company. The Company monitors economic conditions to identify facts or circumstances that may indicate that its receivables are at risk of collection. The Company provides reserves against accounts receivable for estimated losses, if any, that may result from a customer's inability to pay based on the composition of its accounts receivable, current economic conditions, and historical credit loss activity. Amounts determined to be uncollectible are charged or written-off against the reserve. During the years ended December 31, 2023 and 2022, the Company did not record any expected credit losses related to outstanding accounts receivable. Inventory and Cost of Sales Inventories are stated at the lower of cost or estimated net realizable value with cost based on the first-in first-out method. Inventory that can be used in either the production of clinical or commercial products is expensed as research and development costs when identified for use in clinical trials. The Company classifies its inventory costs as long-term when it expects to utilize the inventory beyond its normal operating cycle and includes these costs in long-term investments—restricted and other long-term assets in the consolidated balance sheets. Cost of sales for both product revenues, net and collaboration revenues are based on the sale of inventory used in commercial products. Prior to the regulatory approval of its drug candidates, the Company incurs expenses for the manufacture of drug product supplies to support clinical development that could potentially be available to support the commercial launch of those drugs. Until the date at which initial regulatory approval has been received or is otherwise considered probable, the Company records all such costs as research and development expenses. The Company performs an assessment of the recoverability of capitalized inventories during each reporting period and writes down any excess and obsolete inventory to its net realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded as a component of cost of sales in the Company's consolidated statements of operations and comprehensive loss. The determination of whether inventory costs will be realizable requires the use of estimates by management. If actual market conditions are less favorable than projected by management, additional write-downs of inventory may be required. Long-Term Investment — Restricted The Company's long-term investment—restricted balance is comprised of certificates of deposit. The certificates of deposit are held to secure letters of credit associated with the Company's lease for space at its headquarters location and to secure a credit card. The balances of such accounts are classified as non-current, as the maturities of these instruments are more than one year from the balance sheet date, and are measured at carrying value in the consolidated balance sheets. Property and Equipment Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Asset Category Estimated Useful Life Lab equipment 5 to 7 years Computer equipment 3 to 5 years Furniture and fixtures 7 years Leasehold improvements Shorter of life of lease or 15 years Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the consolidated statements of operations and comprehensive loss. The cost of normal, recurring, or periodic repairs and maintenance activities are expensed as incurred. Leases The Company accounts for a contract as a lease when it has the right to control the asset for a period of time while obtaining substantially all of the asset's economic benefits. The Company determines if an arrangement is a lease or contains an embedded lease at inception. For arrangements that meet the definition of a lease, the Company determines the initial classification and measurement of its operating right-of-use asset and operating lease liability at the lease commencement date and thereafter if modified. The lease term includes any renewal options that the Company is reasonably assured to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its estimated secured incremental borrowing rate for that lease term. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance, and other expenses, which are generally referred to as non-lease components. The Company has elected to not separate lease and non-lease components. Only the fixed costs for lease components and their associated non-lease components are accounted for as a single lease component and recognized as part of a right-of-use asset and liability. Rent expense is recognized on a straight-line basis over the reasonably assured lease term based on the total lease payments and is included in operating expenses in the consolidated statements of operations and comprehensive loss. The Company has made an accounting policy election to not recognize short-term leases, or leases that have a lease term of 12 months or less at commencement date, within its consolidated balance sheets and to recognize those lease payments in the consolidated statements of operations and comprehensive loss on a straight-line basis over the lease term. Sublease All of the Company's leases are operating leases. The Company determines the classification of a sublease at inception. If the sublease is determined to be an operating lease, the Company will recognize sublease income on a straight-line basis over the lease term in the consolidated statement of operations and comprehensive loss as a reduction of the related operating expense. If the sublease is determined to be a sales-type lease or direct financing lease, the Company will derecognize the right-of-use asset from the Company's original lease and record a net investment in the sublease and evaluate for impairment. The Company will account for the lease liability of the original lease based on the accounting for a lease liability in a finance lease. Impairment of Long-Lived Assets Long-lived assets consist of property, equipment, and operating lease assets. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets or asset group may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends, and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the years ended December 31, 2023, 2022, or 2021. Acquired In - Process Research and Development (IPR&D) Acquired IPR&D represents the value assigned to research and development assets that have not reached technological feasibility. Upon the acquisition of IPR&D, the Company completes an assessment of whether the acquisition constitutes the purchase of a single asset or group of assets. The Company considers multiple factors in this assessment, including the nature of the technology acquired, the presence or absence of separate cash flows, the development process and stage of completion, quantitative significance, and the Company's rationale for entering into the transaction. If the Company acquires a business as defined under applicable accounting standards, then the acquired IPR&D is capitalized as an intangible asset on the consolidated balance sheets and recorded at fair value. If the Company acquires an asset or group of assets that do not meet the definition of a business under applicable accounting standards, then the acquired IPR&D is expensed as research and development in the consolidated statements of operations and comprehensive loss on its acquisition date. Future costs to develop these assets are recorded to research and development expense as they are incurred until such time that the asset or group of assets reaches technological feasibility, if ever. Research and Development Costs Research and development costs are expensed as incurred. Research and development expenses are comprised of costs incurred in performing research and development activities, including salaries, stock-based compensation and benefits, facility- and technology-related costs, depreciation, manufacturing expenses, external costs of outside vendors engaged to conduct preclinical development activities and trials, and upfront fees paid to third-parties associated with acquired IPR&D that has not reached technological feasibility. Prior to initial regulatory approval, the Company expenses costs relating to the production of inventory for the Company's drug and drug candidates as research and development expenses within the Company's consolidated statements of operations and comprehensive loss in the period incurred, unless the Company believes regulatory approval and subsequent commercialization of the drug candidate is probable and the Company expects the future economic benefit from sales of the drug to be realized. Advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses within the Company's consolidated balance sheets. The prepaid amounts are expensed as the related goods are delivered or the services are performed. Research Contract Costs and Accruals The Company has entered into various research and development contracts with research institutions and other companies. These agreements are generally cancellable, and related payments are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies or trials, including the phase or completion of events, invoices received, and contracted costs. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company's estimates. The Company's historical accrual estimates have not been materially different from the actual costs. Patent Costs All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as selling, general, and administrative expenses in the consolidated statements of operations and comprehensive loss. Stock-Based Compensation The Company measures all stock options and other stock-based awards granted to employees and directors based on the fair value on the date of the grant and recognizes compensation expense of those awards over the requisite service period, which is generally the vesting period of the respective award. The straight-line method of expense recognition is applied to all awards with service-only conditions while the graded-vesting method is applied to all awards with both service and performance conditions. The Company has granted performance-based awards under which the fair market value of the awards is expensed after assessing the probability that certain performance criteria will be met and the associated targeted payout level that is forecasted will be achieved. The Company accounts for forfeitures as they occur. The Company classifies stock-based compensation expense in its consolidated statements of operations and comprehensive loss in the same manner in which the award recipient's payroll costs are classified or in which the award recipient's service payments are classified. Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company's tax returns. Deferred taxes are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect in the years in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. The Company accounts for uncertainty in income taxes recognized in its consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than- not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties. Comprehensive Loss and Accumulated Other Comprehensive Income (Loss) Comprehensive loss includes net loss as well as other changes in stockholders' equity (deficit) that result from transactions and economic events other than those with shareholders. For the years ended December 31, 2023 and 2022, the Company's other comprehensive income (loss) consisted of foreign currency translation adjustments and unrealized gains (losses) on marketable securities. For the year ended December 31, 2021, the Company's other comprehensive income (loss) consisted of unrealized gains (losses) on marketable securities. As of December 31, 2023 and 2022, accumulated other comprehensive income (loss) primarily consisted of foreign currency translation adjustments and unrealized gains (losses) on marketable securities. Net Loss per Share Basic net income (loss) per share is computed by dividing the net income (loss) by the weighted average number of common shares outstanding, including pre-funded warr

Revenues

Revenues	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenues	Revenues Net Product Revenues To date, the Company's only source of product revenues has been from the sales of QINLOCK, which began in May 2020, following the approval of QINLOCK by the U.S. Food and Drug Administration (FDA) on May 15, 2020, and during 2023, 2022, and 2021 in certain other jurisdictions following regulatory approval or on a named patient basis. Net product revenues by geography consisted of the following and are attributable to individual countries based on the location of the customer: Year Ended December 31, (in thousands) 2023 2022 2021 U.S. $ 121,546 $ 97,216 $ 81,476 Rest of world 19,570 13,947 5,913 Germany 17,958 14,341 — Total product revenues, net $ 159,074 $ 125,504 $ 87,389 The Company primarily sells QINLOCK through specialty distributors and specialty pharmacies. The Company recognized revenues from two customers accounting for 44% and 12% of gross product revenues for the year ended December 31, 2023, respectively, two customers accounting for 40% and 12% of gross product revenues for the year ended December 31, 2022, respectively, and three customers accounting for 57%, 18% and 10% of gross product revenues for the year ended December 31, 2021, respectively. As of December 31, 2023, two customers individually accounted for approximately 53% and 16% of accounts receivable associated with the Company's product sales. As of December 31, 2022, three customers individually accounted for approximately 47%, 15%, and 14% of accounts receivable associated with the Company's product sales. Activity in each of the product revenue allowance and reserve categories is summarized as follows: (in thousands) Trade discounts and allowances Chargebacks and administrative fees Government rebates and other incentives Returns Total Balance as of December 31, 2022 $ 475 $ 656 $ 15,825 $ 1,375 $ 18,331 Provision related to sales in the current year 4,529 10,757 17,984 4,636 37,906 Adjustments related to prior period sales (31) — 80 — 49 Credits and payments made during the period (4,219) (10,533) (9,023) (4,916) (28,691) Balance as of December 31, 2023 $ 754 $ 880 $ 24,866 $ 1,095 $ 27,595 The total reserves described above are summarized as components of the Company's consolidated balance sheets as follows: (in thousands) December 31, 2023 December 31, 2022 Reduction of accounts receivable, net $ 1,528 $ 1,082 Component of accrued expenses and other current liabilities 26,067 17,249 Total revenue-related reserves $ 27,595 $ 18,331 Collaboration Revenues Zai License Agreement In June 2019, the Company entered into the Zai License Agreement, pursuant to which the Company granted Zai exclusive rights to develop and commercialize the Licensed Products in the Territory. The Company retains exclusive rights to, among other things, develop, manufacture, and commercialize the Licensed Products outside the Territory. Pursuant to the terms of the Zai License Agreement, the Company received an upfront cash payment of $20.0 million and three development milestone payments totaling $12.0 million and will be eligible to receive up to $173.0 million in potential development and commercial milestone payments, consisting of up to $38.0 million of development milestones and up to $135.0 million of commercial milestones. In addition, during the term of the Zai License Agreement, Zai will be obligated to pay the Company tiered percentage royalties ranging from low to high teens on annual net sales of the Licensed Products in the Territory, subject to adjustments in specified circumstances. Additionally, certain costs incurred by the Company associated with the Zai License Agreement are reimbursed by Zai. During the years ended December 31, 2023, 2022, and 2021, the Company recognized royalty revenues under the Zai License Agreement, which the Company began recognizing in the second quarter of 2021 following the approval from the China National Medical Products Administration (China NMPA). During the year ended December 31, 2021, revenues recognized under the Zai License Agreement also included the achievement of a $5.0 million development milestone in the first quarter of 2021. Subject to the terms and conditions of the Zai License Agreement, Zai will be responsible for conducting the development and commercialization activities in the Territory related to the Licensed Products. Subject to specified exceptions, during the term of the Zai License Agreement, each party has agreed that neither it nor its affiliates nor, with respect to Zai, its sublicensees, will conduct any development, manufacturing, and commercialization activities in the Territory that may be deemed competitive with the Licensed Products. In addition, under the Zai License Agreement, each party has granted the other party specified intellectual property licenses to enable the other party to perform its obligations and exercise its rights under the Zai License Agreement, including license grants to enable each party to conduct research, development and commercialization activities pursuant to the terms of the Zai License Agreement. The Zai License Agreement will continue on a Licensed Product-by-Licensed Product and region-by-region basis until the later of (i) the abandonment, expiry or final determination of invalidity of the last valid claim within the Company's patent rights that covers the Licensed Product in such region in the Territory; (ii) the expiry of the regulatory exclusivity for such Licensed Product in such region; or (iii) the close of business of the day that is exactly ten (10) years after the date of the first commercial sale of such Licensed Product in such region. Subject to the terms of the Zai License Agreement, Zai may terminate the Zai License Agreement for convenience by providing written notice to the Company, which termination will be effective following a prescribed notice period. In addition, the Company may terminate the Zai License Agreement under specified circumstances if Zai or certain other parties challenge our patent rights or if Zai or its affiliates do not conduct certain development activities with respect to one or more Licensed Products for a specified period of time, subject to specified exceptions. Either party may terminate the Zai License Agreement for the other party's uncured material breach of a material term of the Zai License Agreement, with a customary notice and cure period, or insolvency. After termination (but not natural expiration), the Company is entitled to retain a worldwide and perpetual license from Zai to exploit the Licensed Products. On a region-by-region and a Licensed Product-by-Licensed Product basis, upon the natural expiration of the Zai License Agreement as described above, the licenses granted by the Company to Zai under the Zai License Agreement in such region with respect to the Licensed Product become fully paid-up, perpetual and irrevocable. The Company identified the following promises under the Zai License Agreement: (1) the exclusive license, with the right to grant sublicenses, granted in the Territory for the Licensed Products; (2) initial and continuing know-how transfer for the Licensed Products; (3) clinical supply of the Licensed Products; (4) participation in the joint steering committee (JSC); and (5) regulatory and technical assistance responsibilities. The Company determined that the exclusive license is distinct and constitutes one performance obligation that is a right to use the Company's intellectual property. The Company determined that the promises under the Zai License Agreement related to the know-how transfer, clinical and commercial supply, participation in the JSC, and the assistance responsibilities are immaterial in the context of the Zai License Agreement and therefore are excluded from the assessment of performance obligations. The Company also evaluated certain options and contingent obligations contained within the Zai License Agreement to determine if they provide Zai with any material rights. The Company concluded that the options and contingent obligations were not issued at a significant and incremental discount, and therefore do not provide Zai with a material right. As such, these options and contingent obligations were excluded as performance obligations and will be accounted for if and when they occur or are exercised. In the first quarter of 2021, the Company determined that the $5.0 million development milestone was probable of achievement and that a significant reversal of cumulative revenue would not occur upon resolution of the uncertainty, and constitute consideration to be included in the transaction price of the arrangement. The remaining potential milestone payments that the Company is eligible to receive were excluded from the transaction price and were fully constrained based on the probability of achievement. The Company will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and if necessary, the Company will adjust its estimate of the transaction price. Because the performance obligation has been satisfied, any additions to the transaction price would be fully recognized in the period. The Company assessed the Zai License Agreement to determine whether a significant financing component exists and concluded that a significant financing component does not exist. Zai Supply Agreement In February 2020, the Company entered into the Zai Supply Agreement, as required by terms in the Zai License Agreement, pursuant to which the Company will supply the Licensed Products to Zai for use in the Territory for clinical trials as well as commercial inventory, if QINLOCK obtained regulatory approval in the Territory. QINLOCK was approved in the PRC, Hong Kong, and Taiwan in 2021, and Macau and Singapore in 2023. Subject to the Zai Supply Agreement, costs incurred by the Company for clinical and commercial supply are reimbursed by Zai. During the second quarter of 2021, following the approvals of QINLOCK in the PRC and Hong Kong in March 2021, the Company began recognizing revenues associated with sales of commercial inventory of QINLOCK under the Zai Supply Agreement.

Marketable Securities and Fair

Marketable Securities and Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Marketable Securities and Fair Value Measurements	Marketable Securities and Fair Value Measurements The following tables present marketable securities by contractual maturity and security type: As of December 31, 2023 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Due within one year: U.S. government securities 97,889 15 (93) $ 97,811 Corporate debt securities 82,934 26 (123) 82,837 Commercial paper 39,542 30 (11) 39,561 Certificates of deposit 2,500 — (1) 2,499 Due after one year through five years: U.S. government securities 31,698 34 (151) 31,581 Corporate debt securities 15,060 64 (5) 15,119 Total $ 269,623 $ 169 $ (384) $ 269,408 As of December 31, 2022 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Due within one year: Corporate debt securities $ 113,939 $ 2 $ (571) $ 113,370 Commercial paper 81,344 12 (336) 81,020 Certificates of deposit 33,877 14 (152) 33,739 U.S. government securities 31,761 15 (160) 31,616 Due after one year through five years: Corporate debt securities 11,278 — (38) 11,240 U.S. government securities 3,349 — (39) 3,310 Total $ 275,548 $ 43 $ (1,296) $ 274,295 The following tables present information about the Company's financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values: As of December 31, 2023 (in thousands) Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ — $ 29,829 $ — $ 29,829 Marketable securities: U.S. government securities — 129,392 — 129,392 Corporate debt securities — 97,956 — 97,956 Commercial paper — 39,561 — 39,561 Certificates of deposit — 2,499 — 2,499 Total $ — $ 299,237 $ — $ 299,237 As of December 31, 2022 (in thousands) Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ — $ 27,787 $ — $ 27,787 Certificates of deposit — 14,167 — 14,167 Corporate debt securities — 4,945 — 4,945 Marketable securities: Corporate debt securities — 124,610 — 124,610 Commercial paper — 81,020 — 81,020 U.S. government securities — 34,926 — 34,926 Certificates of deposit — 33,739 — 33,739 Total $ — $ 321,194 $ — $ 321,194 The tables above exclude certificates of deposit of $3.1 million as of both December 31, 2023 and 2022 that the Company held to secure a letter of credit associated with its leases and to secure a credit card account. The certificates of deposit are measured at carrying value in the consolidated balance sheets in long-term investments—restricted and approximate fair value. For additional information on the letter of credit associated with the Company's leases, please read Note 7, Leases , to these consolidated financial statements. The fair value of Level 2 instruments classified as cash equivalents and marketable securities were determined through third-party pricing services. The pricing services use many observable market inputs to determine value, including reportable trades, benchmark yields, credit spreads, broker/dealer quotes, bids, offers, current spot rates, and other industry and economic events. The Company performs validation procedures to ensure the reasonableness of this data. The Company performs its own review of prices received from the independent pricing services by comparing these prices to other sources. After completing the validation procedures, the Company did not adjust or override any fair value measurements provided by the pricing services as of December 31, 2023 and 2022.

Inventory

Inventory	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Inventory	Inventory Capitalized inventory consisted of the following: (in thousands) December 31, 2023 December 31, 2022 Raw materials $ 4,934 $ 6,844 Work in process 18,253 11,125 Finished goods 2,957 2,592 Total inventory $ 26,144 $ 20,561 Long-term inventory, which consists of raw materials, is included in long-term investments—restricted and other long-term assets in the consolidated balance sheets. As of December 31, 2023, $4.9 million was classified as non-current. Inventory written down as a result of excess, obsolescence, unmarketability, or other reasons is charged to cost of sales, and totaled $0.9 million during the year ended December 31, 2022. There were less than $0.1 million in inventory amounts written down and charged to cost of sales during the year ended December 31, 2021. There were no inventory amounts written down and charged to cost of sales during the year ended December 31, 2023.

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net consisted of the following: December 31, (in thousands) 2023 2022 Laboratory equipment $ 6,517 $ 5,515 Computer equipment 5,035 5,018 Furniture and fixtures 3,922 3,919 Leasehold improvements 2,113 2,113 Construction in progress 31 226 Total cost 17,618 16,791 Less: Accumulated depreciation (12,197) (10,084) Total property and equipment, net $ 5,421 $ 6,707 Depreciation expense was $2.1 million, $2.9 million, and $3.0 million for the years ended December 31, 2023, 2022, and 2021, respectively.

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leases	Leases The Company leases real estate, including office and laboratory space. In May 2018, the Company entered into a lease for office space (the Initial Space) at 200 Smith Street in Waltham, Massachusetts (the Premises). The initial term of the lease expires in November 2029, unless terminated earlier in accordance with the terms of the lease. The Company is entitled to two five-year options to extend. The initial annual base rent is approximately $2.0 million and will increase annually for a total of $22.4 million over the lease term. In October 2019, the lease for the Initial Space commenced. The Premises became the Company's new headquarters in October 2019. In April 2019, the Company amended its lease for office space at the Premises to add an additional 38,003 square feet of space (the Additional Space) for a total of 82,346 square feet of space. The initial term of the lease for the Additional Space will expire in November 2029 unless terminated earlier in accordance with the terms of the lease and the Company is entitled to two five-year options to extend the lease. The initial annual base rent for the Additional Space is approximately $1.9 million and will increase annually for a total of $18.2 million over the lease term. In July 2020, the lease for the Additional Space commenced. The Company is required to maintain a letter of credit associated with its leases at the Premises. The balances of the Company's certificate of deposit associated with the letter of credit for its leases at the Premises of $2.1 million as of both December 31, 2023 and 2022 were classified as long-term investment—restricted in the consolidated balance sheets. In August 2020, the Company amended and restated its real estate leases primarily for office and laboratory space in Lawrence, Kansas (the 2020 Lawrence Lease Agreements). The initial term of the 2020 Lawrence Lease Agreements will expire on December 31, 2030 unless terminated earlier in accordance with the terms of the lease and the Company is entitled to two five-year options to extend the leases. The 2020 Lawrence Lease Agreements modified a previously existing operating lease. Additionally, new leases associated with the 2020 Lawrence Lease Agreements commenced during the first and fourth quarters of 2021 resulting in the additions of operating lease assets of $0.5 million and $3.4 million and corresponding lease liabilities of $0.5 million and $1.7 million, respectively. Further, a new lease associated with the 2020 Lawrence Lease Agreements commenced during the second quarter of 2022 resulting in the addition of operating lease assets of $3.8 million and corresponding lease liability of $1.1 million, respectively. The Company's leases contain options to extend the lease terms; however, these extensions were not included in the operating lease assets and lease liabilities recorded on the consolidated balance sheets as they were not reasonably certain of being exercised. During the years ended December 31, 2023, 2022, and 2021 the Company was subject to certain lease agreements with terms of less than 12 months to accommodate short-term or temporary needs and its office space needs to support commercialization efforts in key European markets. The expenses associated with such lease agreements are included in short-term lease costs for the years ended December 31, 2023, 2022, and 2021, as applicable. The Company's leases require the Company to pay for its share of certain operating expenses, taxes, and other expenses based on actual costs incurred and therefore, as the amounts are variable in nature, are expensed in the period incurred and included in variable lease costs for the years ended December 31, 2023, 2022, and 2021. Sublease In May 2022, the Company entered into a sublease agreement to sublease 44,343 square feet of space at 200 Smith Street, Waltham, MA, for a term of three years for $8.9 million over the term of the sublease. The Company determined the sublease to be an operating lease. Therefore the Company will recognize sublease income on a straight-line basis over the lease term in its consolidated statement of operations and comprehensive income. The Company will continue to account for the right-of-use asset and related liability of the original lease as it did prior to the commencement of the sublease. All of the Company's leases qualify as operating leases. The following table summarizes the presentation of the Company's operating leases in the consolidated balance sheet: December 31, (in thousands) 2023 2022 Operating lease right of use assets $ 32,073 $ 36,547 Current operating lease liabilities $ 3,504 $ 3,235 Operating lease liabilities, net of current portion 22,375 25,879 Total operating lease liabilities $ 25,879 $ 29,114 The components of lease expense were as follows: Year Ended December 31, (in thousands) 2023 2022 2021 Operating lease cost $ 6,012 $ 5,809 $ 5,178 Short-term lease cost 60 455 357 Variable lease cost 1,738 1,468 1,225 Sublease income (2,926) (1,736) — Total lease expense, net $ 4,884 $ 5,996 $ 6,760 Future annual minimum lease payments under operating leases are as follows: (in thousands) As of December 31, 2023 2024 $ 4,854 2025 4,936 2026 5,019 2027 5,101 2028 5,183 Thereafter 5,535 Total future minimum lease payments 30,628 Less: imputed interest (4,749) Total operating lease liabilities $ 25,879 The weighted-average remaining lease term and weighted-average discount rate of the Company's operating leases are as follows: As of December 31, 2023 2022 Weighted-average remaining lease term in years 6.08 6.97 Weighted-average discount rate 5.55 % 5.59 % Supplemental disclosure of cash flow information related to the Company's operating leases included in cash flows used in operating activities in the consolidated statement of cash flows were as follows: Year Ended December 31, (in thousands) 2023 2022 2021 Cash paid for amounts included in the measurement of operating lease liabilities $ 4,772 $ 4,617 $ 4,243 Operating lease liabilities arising from obtaining operating lease assets $ — $ 1,188 $ 2,150

Other Consolidated Financial De

Other Consolidated Financial Detail	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Other Consolidated Financial Detail	. Other Consolidated Financial Detail Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: December 31, (in thousands) 2023 2022 External research and development expenses $ 16,095 $ 17,411 Payroll and related expenses 20,519 21,971 Revenue-related reserves 26,067 17,249 Professional fees 5,669 4,275 Other 1,945 3,716 Total accrued expenses and other current liabilities $ 70,295 $ 64,622 Interest Income For the years ended December 31, 2023, 2022, and 2021, interest income was $16.7 million, $5.1 million, and $0.6 million, respectively.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Undesignated Preferred Stock The Company's board of directors has the authority, without further action by its stockholders, to issue up to 5,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting, or the designation of, such series, any or all of which may be greater than the rights of common stock. The issuance of preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon the Company's liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of the Company or other corporate action. There are no shares of preferred stock outstanding as of December 31, 2023. Common Stock In April 2022, the Company entered into an underwriting agreement with J.P. Morgan Securities LLC and Jefferies, as representatives of the several underwriters named therein, relating to the issuance and sale of an aggregate of 7,501,239 shares of its common stock at a public offering price of $10.00 per share to certain investors. In addition, the Company issued and sold pre-funded warrants to purchase 9,748,761 shares of its common stock at a public offering price of $9.99 per pre-funded warrant, which equals the public offering price per share of the common stock less the $0.01 exercise price per share of each pre-funded warrant. The offering closed on April 29, 2022, resulting in net proceeds of $163.4 million, after deducting underwriting discounts and commissions and other offering expenses. Additionally, during the years ended December 31, 2023 and 2022, 2,427,693 and 892,798 shares of pre-funded warrants exercised, respectively, resulting in net proceeds of less than $0.1 million in each year. For additional information on the pre-funded warrants, please read Note 1, Nature of the Business and Basis of Presentation , to these consolidated financial statements. On August 4, 2022, the Company entered into the Amended Sales Agreement, pursuant to which the Company may issue and sell shares of its common stock in "at the market offerings" having aggregate offering proceeds of up to $200.0 million from time to time through Jefferies as its sales agent. During the year ended December 31, 2021, the Company issued 172,094 shares resulting in net proceeds of $8.5 million after deducting commissions and other offering expenses, under the August 2020 Sales Agreement. During the years ended, December 31, 2023 and 2022, the Company did not issue any shares under the August 2020 Sales Agreement or the Amended Sales Agreement. For additional information on the August 2020 Sales Agreement and Amended Sales Agreement, please read Note 1, Nature of the Business and Basis of Presentation , to these consolidated financial statements. On January 18, 2023, the Company delivered written notice to Jefferies that it was suspending and terminating the prospectus related to the common stock issuable pursuant to the terms of the Amended Sales Agreement. As a result, the Company will not make any sales of its securities pursuant to the Amended Sales Agreement, unless and until a new prospectus, prospectus supplement, or a new registration statement is filed. The Amended Sales Agreement was superseded by the May 2023 Sales Agreement. In January 2023, the Company entered into an underwriting agreement with J.P. Morgan Securities LLC, Jefferies, Cowen and Company, LLC, and Guggenheim Securities, LLC, as representatives of the several underwriters named therein, relating to the issuance and sale of an aggregate of 7,986,111 shares of its common stock at a public offering price of $18.00 per share. The offering closed on January 24, 2023, resulting in net proceeds of $134.5 million, after deducting underwriting discounts and commissions and other offering expenses. In May 2023, the Company entered into the May 2023 Sales Agreement with Jefferies, pursuant to which the Company may issue and sell the Shares having aggregate offering proceeds of up to $200.0 million from time to time through Jefferies as its sales agent. Upon delivery of a placement notice and subject to the terms and conditions of the Sales Agreement, Jefferies may sell the Shares by any method permitted by law deemed to be an "at the market offering" as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended. The Company may sell the Shares in amounts and at times to be determined by the Company from time to time subject to the terms and conditions of the Sales Agreement, but it has no obligation to sell any Shares under the Sales Agreement. The Company or Jefferies may suspend or terminate the offering of Shares upon notice to the other party and subject to other conditions. During the year ended December 31, 2023, the Company issued 1,004,185 shares resulting in net proceeds of $14.6 million, after deducting commissions and other offering expenses, under the May 2023 Sales Agreement. As of December 31, 2023, there was up to $185.0 million available for future issuance under the May 2023 Sales Agreement.

Stock-Based Awards

Stock-Based Awards	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Awards	Stock-Based Awards 2017 Equity Incentive Plan The Company's 2017 Stock Option and Incentive Plan (the 2017 Plan) provides for the grant of equity-based incentive awards. The number of shares initially reserved for issuance of awards under the 2017 Plan was 2,655,831 shares of common stock and may be increased by the number of shares under the 2015 Equity Incentive Plan (the 2015 Plan) and the 2017 Plan that are forfeited, cancelled, repurchased by the Company, or otherwise surrendered. The 2017 Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2018, by 4% of the outstanding number of shares of our common stock on the immediately preceding December 31, or such lesser number of shares as determined by the Compensation Committee of the Company's Board of Directors. As of December 31, 2023, 1,471,244 remained available for issuance under the 2017 Plan. The number of shares reserved for issuance under the 2017 Plan was increased by 3,220,133 shares effective January 1, 2024. Inducement Plan In January 2022, the Company adopted the Inducement Plan pursuant to which the Company initially reserved 800,000 shares of common stock to be used exclusively for grants of equity-based awards to individuals who were not previously employees or directors of the Company, as an inducement material to the individual’s entry into employment with the Company within the meaning of Rule 5635(c)(4) of the Marketplace Rules of the Nasdaq Stock Market, Inc. The Inducement Plan provides for the grant of equity-based awards in the form of nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, unrestricted stock awards, and dividend equivalent rights. The Inducement Plan was adopted by the Company without stockholder approval pursuant to Rule 5635(c)(4) of the Marketplace Rules of the Nasdaq Stock Market, Inc. In February 2023, the Inducement Plan was amended and the number of shares reserved for issuance under the Inducement Plan was increased by 270,000 to return the number of shares available for issuance to the amount initially reserved. As of December 31, 2023, 444,400 shares of common stock were available for issuance under the Inducement Plan. In February 2024, the Inducement Plan was amended and the number of shares reserved for issuance under the Inducement Plan was increased by 355,600. 2015 Equity Incentive Plan Under the 2015 Plan the Company was authorized to sell or issue common shares or restricted common shares, or to grant options for the purchase of common shares, share appreciation rights, and other awards, to employees, members of the board of directors, consultants, and advisors of the Company. Upon effectiveness of the 2017 Plan no further awards were available to be issued under the 2015 Plan. Both the 2017 and 2015 Plans provide that they be administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. The exercise prices for stock options may not be less than 100% of the fair market value of the common stock on the date of grant and the term of awards may not be greater than ten years. The Company bases fair value of common stock on the quoted market price. Vesting periods are determined at the discretion of the board of directors. Awards granted to employees typically vest over four years and directors over one year. 2017 Employee Stock Purchase Plan The 2017 Employee Stock Purchase Plan (the ESPP) initially reserved and authorized the issuance of up to 306,750 shares of common stock to participating employees. The ESPP provides that the number of shares reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2018 and each January 1 thereafter through January 1, 2027, by the least of (i) 1% of the outstanding number of shares of common stock on the immediately preceding December 31; (ii) 400,000; shares or (iii) such number of shares as determined by the ESPP administrator. As of December 31, 2023, 2,219,550 remained available for issuance under the ESPP Plan. The number of shares reserved for issuance under the ESPP was increased by 400,000 shares effective January 1, 2024. The purchase price of common stock under the ESPP is equal to 85% of the lesser of (i) the fair market value per share of the common stock on the first business day of an offering period and (ii) the fair market value per share of the common stock on the purchase date. The fair value of the discounted purchases made under the ESPP is calculated using the Black-Scholes option-pricing model, which is described in further detail within the "Stock Option Valuation" section below, on the date of the first day of the offering period. The fair value of the look-back provision plus the 15% discount is recognized as stock-based compensation expense in the consolidated statements of operations and comprehensive loss over the 6-month purchase period. Employees began participating in the ESPP program during the first offering period of the ESPP program in the second quarter of 2020. There were 113,019, 148,619, and 90,947 shares of common stock issued under the ESPP during the years ended December 31, 2023, 2022, and 2021, respectively. Stock Option Valuation The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option-pricing model, which uses as inputs the fair value of the Company's common stock and assumptions for the volatility of its common stock, the expected term of stock-based awards, the risk-free interest rate for a period that approximates the expected term of stock-based awards, and the expected dividend yield. Prior to October 2017, the Company was privately-held and lacked company-specific historical and implied volatility information. Therefore, it estimates its expected share volatility based on the historical volatility of a set of publicly traded peer companies as well as the limited historical volatility of its own traded stock price. The Company estimated the expected term of its options using the "simplified" method for awards that qualify as "plain-vanilla" options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends on common shares and does not expect to pay any cash dividends in the foreseeable future. The assumptions that the Company used to determine the fair value of options granted to employees and directors were as follows, presented on a weighted average basis: Year Ended December 31, 2023 2022 2021 Risk-free interest rate 4.0 % 2.0 % 1.0 % Expected term (in years) 6.0 6.0 5.8 Expected volatility 85.5 % 78.2 % 77.8 % Expected dividend yield 0 % 0 % 0 % The following table summarizes the Company's option activity from January 1, 2023 to December 31, 2023: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding as of December 31, 2022 8,279,217 $ 24.26 Granted 1,489,555 $ 15.36 Exercised (190,126) $ 8.42 Forfeited (156,603) $ 22.04 Expired (162,575) $ 36.29 Outstanding as of December 31, 2023 9,259,468 $ 22.98 6.7 $ 27,665 Options vested and expected to vest as of December 31, 2023 9,259,468 $ 22.98 6.7 $ 27,665 Options exercisable as of December 31, 2023 6,879,959 $ 24.96 6.1 $ 20,792 The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company's common shares for those options that had exercise prices lower than the fair value of the Company's common shares. The aggregate intrinsic value of options exercised during the years ended December 31, 2023, 2022, and 2021 was $1.0 million, $0.4 million, and $15.7 million, respectively. The weighted average grant-date fair value per share of options granted during the years ended December 31, 2023, 2022, and 2021 was $11.30, $6.48, and $17.95, respectively. Restricted Stock Units The 2017 Plan provides for the award of restricted stock units. During the years ended December 31, 2023, 2022, and 2021, the Company granted restricted stock units to employees that were subject to time-based vesting conditions that lapse between one year and four years from date of grant, assuming continued employment. From time to time, the Company may also grant restricted stock units that are subject to performance-based vesting conditions. All restricted stock units currently granted have been classified as equity instruments as their terms require settlement in shares. Restricted stock units with time-based and performance-based vesting conditions are valued on the grant date using the grant date market price of the underlying shares. The table below summarizes the Company's time-based restricted stock unit activity from January 1, 2023 to December 31, 2023: Number Weighted Unvested at December 31, 2022 2,077,988 $ 18.09 Granted 1,743,194 $ 15.14 Vested (892,882) $ 19.02 Forfeited (393,995) $ 16.92 Unvested at December 31, 2023 2,534,305 $ 15.91 The fair value of time-based restricted stock units that vested during the years ended December 31, 2023, 2022, and 2021 were $14.7 million, $6.2 million, and $4.7 million respectively. During 2023, the Company granted restricted stock units that were subject to performance-based vesting conditions. Vesting of such performance-based restricted stock units is contingent upon meeting any of three specific performance obligations associated with the achievement of certain research and development activities and continued employment through the service period. During the year ended December 31, 2023, two of the performance obligations became probable and were achieved during the fourth quarter of 2023. The table below summarizes the Company's performance-based restricted stock unit activity from January 1, 2023 to December 31, 2023: Number Weighted Unvested at December 31, 2022 — $ — Granted 377,949 $ 15.48 Vested (251,971) $ 15.48 Forfeited (5,575) $ 15.48 Unvested at December 31, 2023 120,403 $ 15.48 The Company granted no performance-based restricted stock units in 2022 or 2021. The fair value of performance-based restricted stock units that vested during the year ended December 31, 2023 was $3.2 million. No performance-based restricted stock units vested in 2022 or 2021 and no performance-based restricted stock units were outstanding as of December 31, 2022 and 2021. Stock-Based Compensation Expense Stock-based compensation expense was classified in the statements of operations and comprehensive loss as follows: Year Ended December 31, (in thousands) 2023 2022 2021 Research and development $ 21,775 $ 22,238 $ 20,698 Selling, general, and administrative 28,828 29,704 25,380 Total stock-based compensation $ 50,603 $ 51,942 $ 46,078 The following table summarizes share-based compensation expense associated with each of our share-based compensation arrangements: Year Ended December 31, (in thousands) 2023 2022 2021 Stock options $ 26,685 $ 34,861 $ 36,263 Time-based restricted stock units 19,526 16,537 9,047 Performance-based restricted stock units 3,900 — — Employee stock purchase plan 492 544 768 Total stock-based compensation expense $ 50,603 $ 51,942 $ 46,078 As of December 31, 2023, total unrecognized compensation cost related to the unvested share-based awards was $54.5 million, which is expected to be recognized over a weighted average of 2.0 years. During the year ended December 31, 2023, of the $3.9 million charged to stock-based compensation expense associated with performance-based restricted stock units, $2.9 million and $1.0 million were classified as selling, general, and administrative and research and development, respectively, within the consolidated statements of operations and comprehensive loss.

In-License Agreement

In-License Agreement	12 Months Ended
	Dec. 31, 2023
Business Combination and Asset Acquisition [Abstract]
In-License Agreement	In-License Agreement In August 2021, the Company entered into an agreement with Sprint Bioscience (Sprint) to exclusively in-license worldwide rights to a research-stage program targeting VPS34, a key kinase in the autophagy pathway for the potential treatment of cancer (the Sprint Agreement). The Company accounted for this transaction as an asset acquisition as the value being acquired primarily relates to a single IPR&D asset. Pursuant to the terms of the Sprint Agreement, the Company made an upfront payment of $4.0 million during the third quarter of 2021, which was recorded as research and development expense within the consolidated statements of operations and comprehensive loss during the year ended December 31, 2021 as the acquired asset had not yet reached technological feasibility. In January 2024, the Company terminated the Sprint Agreement, pursuant to which Sprint received a reversion license to VPS34. No amounts were due upon the termination of the Sprint Agreement.

401(k) Savings Plan

401(k) Savings Plan	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
401(k) Savings Plan	401(k) Savings Plan Effective January 1, 2018, the Company adopted the 2018 401(k) Plan, a defined contribution plan under Section 401(k) of the Internal Revenue Code, whereby the Company provides matching contributions of 100% of each employee's contribution up to a maximum matching contribution of 3% of the employee's eligible compensation and at a rate of 50% of each employee's contribution in excess of 3% up to a maximum of 5% of the employee's eligible compensation. Total employer matching contributions related to the 2018 401(k) Plan were $2.4 million, $2.7 million, and $2.8 million for the years ended December 31, 2023, 2022, and 2021, respectively.

Restructuring

Restructuring	3 Months Ended
	Dec. 31, 2023
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring In November 2021, the Company announced a corporate restructuring intended to prioritize clinical development of select programs, streamline commercial operations, maintain a focus on discovery research, and extend its cash runway. The corporate restructuring included a workforce reduction of approximately 35%, or approximately 140 positions, as well as discontinuation costs such as contract termination fees and non-cancellable commitments related to the rebastinib and ripretinib programs. These amounts were incurred and paid by the end of 2022. The Company recognized a one-time charge in the fourth quarter of 2021 of approximately $26.2 million. This charge included approximately $9.8 million of employee-related termination costs and approximately $16.3 million of discontinuation costs such as contract termination fees and non-cancellable commitments related to the rebastinib and ripretinib programs. For the year ended December 31, 2021, approximately $22.2 million and $4.0 million was recognized in research and development expenses and selling, general, and administrative expenses, respectively, on the Company's consolidated statements of operations and comprehensive loss. The restructuring reserve was included in accrued expenses and other current liabilities in the Company’s consolidated balance sheets. The following table summarized the charges and spending related to the Company’s restructuring efforts during 2021 and 2022: (in thousands) Workforce Reduction Pipeline Programs Total Restructuring charges incurred during the fourth quarter of 2021 $ 9,835 $ 16,335 $ 26,170 Amounts previously included in prepaid and other current assets — (2,927) (2,927) Reserves established 9,835 13,408 23,243 Amounts paid through December 31, 2021 (2,452) — (2,452) Restructuring reserve as of December 31, 2021 $ 7,383 $ 13,408 $ 20,791 Adjustments to previous estimates, net (374) 192 (182) Amounts paid during the year ended December 31, 2022 (7,009) (13,600) (20,609) Restructuring reserve as of December 31, 2022 $ — $ — $ —

Net Loss per Share

Net Loss per Share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss per Share Basic net income (loss) per share is computed by dividing the net income (loss) by the weighted average number of common shares outstanding, including pre-funded warrants, for the period. Diluted net income (loss) per share is computed by dividing the diluted net income (loss) by the weighted average number of common shares, including potential dilutive common shares assuming the dilutive effect as determined using the treasury stock method. For periods in which the Company has reported net losses, diluted net loss per common share is the same as basic net loss per common share, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. The Company reported a net loss during each of the periods presented. Basic and diluted net loss per share was calculated as follows: Year Ended December 31, (in thousands, except share and per share amounts) 2023 2022 2021 Numerator: Net loss $ (194,942) $ (178,931) $ (299,964) Denominator: Weighted average common shares outstanding—basic and diluted 85,059,962 75,500,148 58,084,325 Net loss per share—basic and diluted $ (2.29) $ (2.37) $ (5.16) Common Stock Equivalents The following potential dilutive securities, presented based on amounts outstanding at the end of each reporting period, have been excluded from the calculation of diluted net loss per share because including them would have had an anti-dilutive impact: As of December 31, 2023 2022 2021 Options to purchase common stock 9,259,468 8,279,217 7,439,508 Unvested restricted stock units 2,534,305 2,077,988 1,537,732 Unvested employee stock purchase plan shares 84,623 61,307 211,822 Total 11,878,396 10,418,512 9,189,062

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes On October 2, 2017, immediately prior to the completion of its initial public offering (IPO), the Company engaged in a series of transactions whereby Deciphera Pharmaceuticals, LLC became a wholly owned subsidiary of Deciphera Pharmaceuticals, Inc., a Delaware corporation. As part of the transactions, shareholders of Deciphera Pharmaceuticals, LLC exchanged their shares of Deciphera Pharmaceuticals, LLC for shares of Deciphera Pharmaceuticals, Inc. on a one-for-5.65 basis (the Conversion). Prior to the Conversion on October 2, 2017, the Company had been treated as a partnership for tax purposes and had not been subject to U.S. federal or state income taxation. As a result, the Company had not recorded any U.S. federal or state income tax benefits for the net losses incurred prior to October 2, 2017 or for earned research and orphan drug credits as the operating losses incurred by the Company had been passed through to its members. Upon consummation of the Conversion on October 2, 2017, the Company became subject to Corporate U.S. federal and state income taxes. During the years ended December 31, 2023, 2022, and 2021, the Company reported net losses, and as a result, recorded no income tax benefits for the net operating losses (NOLs), due to its uncertainty of realizing a benefit from those items. Net loss before income tax expense by jurisdiction is as follows: Year Ended December 31, (in thousands) 2023 2022 2021 U.S. $ (191,378) $ (173,072) $ (281,129) Foreign (3,133) (5,137) (18,835) Net loss before income tax expense $ (194,511) $ (178,209) $ (299,964) The provision for income taxes consisted of the following: Year Ended December 31, (in thousands) 2023 2022 2021 Current provision: Federal $ — $ — $ — State — 166 — Foreign 431 556 — Total current provision 431 722 — Total provision for income taxes $ 431 $ 722 $ — A reconciliation of the U.S. federal statutory income tax rate to the Company's effective income tax rate is as follows: Year Ended December 31, 2023 2022 2021 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % State taxes, including credits, net of federal benefit 2.4 4.4 3.2 Federal research and orphan drug credit 6.1 4.2 2.5 Stock-based compensation (2.2) (3.6) 0.1 Permanent adjustments and other (1.9) (1.3) (0.3) Increase in deferred tax asset valuation allowance (25.6) (25.1) (26.5) Effective income tax rate (0.2 %) (0.4 %) — % During 2022, the Company completed a detailed study of its research and development and orphan drug credits. As a result, the Company adjusted its deferred tax asset balances and the impacts are included in the research and orphan drug credit line in the effective rate reconciliation above. The impacts of the 2022 increase of $0.8 million in the deferred tax asset balances have been completely offset by an increase in the Company's valuation allowance which is included in the change in deferred tax asset valuation allowance line in the reconciliation above. The Tax Cuts and Jobs Act (TCJA) requires taxpayers to capitalize and amortize research and experimental (R&D) expenditures under section 174 for tax years beginning after December 31, 2021. These rules became effective for the Company during the year ended December 31, 2022 and the rules are also in effect for its foreign subsidiaries and the calculation of global intangible low-taxes income (GILTI) for the Company. As a result, the Company has capitalized worldwide R&D costs of $223.4 million and $176.9 million for the years ended December 31, 2023 and 2022, respectively. The Company will amortize these costs for tax purposes over 5 years if the R&D was performed in the U.S. and over 15 years if the R&D was performed outside the U.S. Net deferred tax assets consisted of the following: December 31, (in thousands) 2023 2022 Deferred tax assets (liabilities): Net operating loss carryforwards $ 210,790 $ 213,710 Research and orphan drug credit carryforwards 59,495 47,418 Stock-based compensation 23,371 20,134 Accrued expenses 7,484 6,944 Operating lease liabilities 7,563 8,699 Property and equipment (149) (131) Operating lease assets (7,042) (8,158) Research and development capitalization 74,551 37,797 Other 1,004 893 Total gross deferred tax assets 377,067 327,306 Valuation allowance (377,067) (327,306) Net deferred tax assets $ — $ — The change in the valuation allowance was as follows: Year Ended December 31, (in thousands) 2023 2022 Valuation allowance as of beginning of year $ (327,306) $ (282,536) Net increases recorded to income tax provision (49,761) (44,770) Valuation allowance as of end of year $ (377,067) $ (327,306) As of December 31, 2023, the Company had NOL carryforwards for federal income tax purposes of $827.3 million, of which all may be carried forward indefinitely but are subject to an 80% limitation. As of December 31, 2023, the Company had NOL carryforwards for state income tax purposes of $733.4 million, which begin to expire in 2027. As of December 31, 2023, the Company also had available research and orphan drug credit carryforwards for federal and state income tax purposes of $55.7 million and $4.8 million, respectively, which begin to expire in 2037 and 2032, respectively. We also had foreign NOL carryforwards of $29.8 million as of December 31, 2023, which will begin to expire in 2026. Utilization of the NOL carryforwards and research and orphan drug credit carryforwards may be subject to a substantial annual limitation under Section 382 of the Internal Revenue Code of 1986, as amended (the Code), and similar state law due to ownership changes that could occur in the future. These ownership changes may limit the amount of carryforwards that can be utilized annually to offset future taxable income. If the Company experiences a change of control, as defined by Section 382 of the Code and similar state law, at any time since the IPO, utilization of the NOL carryforwards or research and orphan drug credit carryforwards may be subject to an annual limitation under Section 382 of the Code, which is determined by first multiplying the value of the Company's stock at the time of the ownership change by the applicable long-term tax-exempt rate, and then could be subject to additional adjustments, as required. Any limitation may result in expiration of a portion of the NOL carryforwards or research and orphan drug credit carryforwards before utilization. The Company performed an analysis of ownership changes through December 31, 2023. Based on this analysis, the Company does not believe that any of its tax attributes through December 31, 2023 will expire unutilized due to Section 382 limitations. The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management has considered the Company's history of cumulative net losses incurred since inception and has concluded that it is more likely than not that the Company will not realize the benefits of the deferred tax assets. Accordingly, a full valuation allowance has been established against the deferred tax assets as of December 31, 2023. Management reevaluates the positive and negative evidence at each reporting period. The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal, state, and foreign jurisdictions, where applicable. There are currently no pending income tax examinations. The Company's tax years that are open under statute are from December 31, 2020 to the present, although carryforward attributes that were generated prior to 2020 may still be adjusted upon examination by the IRS or state tax authorities if they either have been or will be used in a future period. The Company's policy is to record interest and penalties related to income taxes as part of its income tax provision. As of December 31, 2023, the unremitted earnings of the Company's foreign subsidiaries are not material. The Company has not provided for U.S. income taxes or foreign withholding taxes on these earnings as it is the Company's current intention to permanently reinvest these earnings outside the U.S. The tax liability on these earnings is also not material. Events that could trigger a tax liability include, but are not limited to, distributions, reorganizations or restructurings and/or tax law changes. Uncertain tax positions represent tax positions for which reserves have been established. As of December 31, 2023, the Company has certain gross unrecognized tax benefits primarily related to the Company's federal and state research and orphan drug credit carryforwards. The Company will recognize interest and penalties related to uncertain tax positions in income tax expense when, if ever, it is in a taxable income position. As of December 31, 2023 and 2022, the Company had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in the Company's statement of operations and comprehensive loss. A reconciliation of the beginning and ending amount of uncertain tax positions is summarized as follows: Year Ended December 31, (in thousands) 2023 2022 Beginning Balance $ 1,857 $ 2,355 Additions based on tax positions for the current period 1,284 635 Additions (reductions) for tax positions of prior periods — (1,133) Ending Balance $ 3,141 $ 1,857

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Purchase Commitments Associated with Commercial Supply Agreements The Company has entered into commercial supply agreements related to the supply of QINLOCK that require the Company to make binding forecasts for a certain amount of purchases. The related cancellation clauses would as a general matter require the Company to pay the full amount of these binding forecasts. As of December 31, 2023, the Company's contractual commitments for its commercial supply agreements were $11.0 million, which is expected to be paid within one year. During the years ended December 31, 2023, 2022, and 2021, the Company made $10.0 million, $9.6 million, and $9.1 million, respectively, of payments for purchases associated with its commercial supply agreements. Legal Proceedings The Company is not currently a party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses the costs related to its legal proceedings as they are incurred. Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners, and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and senior management that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations in its consolidated financial statements as of December 31, 2023 or 2022.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net loss	$ (194,942)	$ (178,931)	$ (299,964)

Insider Trading Arrangements

Insider Trading Arrangements - Steven L. Hoerter [Member]	3 Months Ended	12 Months Ended
	Dec. 31, 2023 shares	Dec. 31, 2023 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		During the quarter ended December 31, 2023, Steven L. Hoerter, our Chief Executive Officer and an executive officer, terminated a trading arrangement for the sale of securities of the Company's common stock (terminated Rule 10b5-1 Trading Plan) that was intended to satisfy the affirmative defense conditions of Securities Exchange Act Rule 10b5-1(c). The terminated Rule 10b5-1 Trading Plan was adopted on June 13, 2023 and would have continued until June 30, 2024 if not earlier terminated. Under the terminated Rule 10b5-1 Trading Plan, an aggregate number of 237,500 securities could be sold or purchased during the duration of the terminated Rule 10b5-1 Trading Plan, which includes any shares sold to cover mandatory tax withholding obligations. No shares were triggered under the terminated Rule 10b5-1 Trading Plan prior to termination.
Name	Steven L. Hoerter
Title	Chief Executive Officer and an executive officer
Adoption Date	June 13, 2023
Rule 10b5-1 Arrangement Terminated	true
Aggregate Available	237,500	237,500

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, product revenue reserves, the accrual for research and development expenses, and the valuation of stock-based option awards. Estimates are periodically reviewed in light of changes in circumstances, facts, and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.
Segment Information	Segment Information The Company manages its operations, and the Company's chief operating decision maker views the Company's business, as a single segment for the purposes of making decisions on how to allocate resources and assessing performance. The Company's focus is discovering, developing, and commercializing important new medicines to improve the lives of people with cancer by leveraging its proprietary switch-control inhibitor platform and deep expertise in kinase biology. The Company designs kinase inhibitors to target the switch pocket region of the kinase with the goal of developing potentially transformative medicines and develop a broad portfolio of innovative medicines to improve treatment outcomes. The Company operates in the U.S. and Europe. Primarily all of the Company's long-lived assets reside in the U.S.
Revenues	Revenues The Company recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. Product Revenues QINLOCK is approved in Australia, Canada, China, the EU, Hong Kong, Iceland, Israel, Liechtenstein, Macau, Norway, New Zealand, Singapore, Switzerland, Taiwan, the U.S. and the U.K. for the treatment of fourth-line GIST. The Company recognizes product revenues, net of variable consideration related to certain allowances and accruals, when the customer takes control of the product, which is typically upon delivery to the customer. Product revenue is recorded at the net sales price, or transaction price. The Company records product revenue reserves, which are classified as a reduction in product revenues, to account for the components of variable consideration. Variable consideration includes the following components: chargebacks, government rebates, trade discounts and allowances, product returns, and other incentives, which are described below. These reserves are based on estimates of the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable (if the amount is payable to the Company's customer) or a liability (if the amount is payable to a party other than the Company's customer, other than product returns, which are recorded as liabilities). The Company's estimates of reserves established for variable consideration are calculated based upon a consistent application of the expected value method, which is the sum of probability-weighted amounts in a range of possible consideration amounts. These estimates reflect the Company's historical experience, current contractual and statutory requirements, specific known market events and trends, industry data, forecasted customer buying, and payment patterns. The amount of variable consideration that is included in the transaction price may be subject to constraint and is included in net product revenues only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration received may ultimately differ from the Company's estimates. If actual results vary, the Company adjusts these estimates, which could have an effect on earnings in the period of adjustment. Chargebacks and administrative fees: Chargebacks for discounts represent the Company's estimated obligations resulting from contractual commitments to sell product to qualified healthcare providers and government agencies at prices lower than the list prices charged to the customers who directly purchase the product from the Company. The customers charge the Company for the difference between what the customers pay the Company for the product and the customer's ultimate contractually committed or government required lower selling price to the qualified healthcare providers. As part of the Company's contractual commitments to sell product to qualified healthcare providers, the Company pays fees for administrative services, such as account management and data reporting. Government rebates: Government rebates consist of Medicare, Tricare, Medicaid, and other governmental rebates in the U.S. and other similar programs in other countries, including countries in which the Company is accruing for estimated rebates because final pricing has not yet been negotiated. These reserves are recorded in the same period the related revenue is recognized. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom it will owe a rebate under the Medicare Part D program. Trade discounts and allowances: The Company provides the customers with discounts that are explicitly stated in the contracts and recorded in the period the related product revenue is recognized. In addition, the Company also receives sales order management, inventory management, and data services from the customers in exchange for certain fees. Product returns: The Company estimates the amount of its product sales that may be returned by its customers and records this estimate in the period the related product revenue is recognized. The Company currently estimates product return liabilities based on available industry data and its visibility into the inventory remaining in the distribution channel. Other incentives: Other incentives include co-payment assistance provided to qualified patients, whereby the Company may provide financial assistance to patients with prescription drug co-payments required by the patient's insurance provider. Reserves for co-payment assistance are recorded in the same period the related revenue is recognized. Collaboration Revenues In June 2019, the Company entered into a License Agreement (the Zai License Agreement) with an affiliate of Zai Lab (Shanghai) Co., Ltd. (Zai), pursuant to which the Company granted Zai exclusive rights to develop and commercialize QINLOCK, including certain follow-on compounds (the Licensed Products), in Greater China (the Territory). In February 2020, the Company entered into a Supply Agreement (the Zai Supply Agreement), as required by terms in the Zai License Agreement, pursuant to which the Company supplies the Licensed Products to Zai for use in the Territory for commercial inventory and clinical trials. Subject to the Zai Supply Agreement, costs incurred by the Company for external manufacturing services are reimbursed by Zai. The Zai License Agreement includes development and regulatory milestone payments. Therefore, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant cumulative revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company's control or the licensee's control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. The Zai License Agreement also includes sales-based royalties for the license of intellectual property, including milestone payments based on the level of sales. As the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied. The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time, and if over time, recognition is based on the use of an output or input method. For additional information on the Zai License Agreement and Zai Supply Agreement, please read Note 3, Revenues , to these consolidated financial statements.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments with original maturities of 90 days or less at the date of purchase to be cash equivalents.
Marketable Securities	Marketable Securities Marketable securities consist of investments with original maturities greater than 90 days at the date of purchase. As of December 31, 2023 and 2022, the Company's marketable securities were comprised of debt securities, commercial paper, U.S. government securities and the Company considers its marketable securities portfolio to be available-for-sale. Available-for-sale marketable securities are classified as current or non-current based on each instrument's underlying effective maturity date and for which the Company has the intent and ability to hold the investment for a period of greater than 12 months. Marketable securities with maturities of less than 12 months from the balance sheet date are classified as current and are included in short-term marketable securities in the consolidated balance sheets. Marketable securities with maturities greater than 12 months from the balance sheet date for which we have the intent and ability to hold the investment for greater than 12 months are classified as non-current and are included in long-term marketable securities in the consolidated balance sheets. Available-for-sale marketable debt securities are recorded at fair market value and unrealized gains and losses are included in accumulated other comprehensive income (loss) in equity, net of related tax effects, except for the changes in allowance for expected credit losses, which are recorded in other income (expense), net, within the consolidated statements of operations and comprehensive loss. Realized gains and losses are reported in other income (expense), net, within the consolidated statements of operations and comprehensive loss on a specific identification basis. The Company conducts periodic reviews to identify and evaluate each investment in the Company's portfolio that has an unrealized loss to determine whether a credit loss exists. An unrealized loss exists when the current fair value of an individual security is less than its amortized cost basis. A credit loss is estimated by considering available information relevant to the collectability of the security and information about past events, current conditions, and reasonable and supportable forecasts. Any credit loss is recorded as a charge to other income (expense), net, not to exceed the amount of the unrealized loss. Unrealized losses other than the credit loss are recognized in accumulated other comprehensive income (loss). When determining whether a credit loss exists, the Company considers several factors, including whether the Company has the intent to sell the security or whether it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis. If the Company has an intent to sell, or if it is more likely than not that the Company will be required to sell a debt security in an unrealized loss position before recovery of its amortized cost basis, the Company will write down the security to its fair value and record the corresponding charge as a component of other income (expense), net. No declines in value were deemed to be credit losses during the years ended December 31, 2023, 2022 or 2021.
Fair Value Measurements	Fair Value Measurements Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies, and similar techniques. The Company's cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy described above. For additional information on the Company's fair value hierarchy, please read Note 4, Marketable Securities and Fair Value Measurements , to these consolidated financial statements. The carrying values of the Company's accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities.
Concentrations of Credit Risk and of Significant Suppliers	Concentrations of Credit Risk and of Significant Suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company maintains all cash, cash equivalents, and marketable securities at accredited financial institutions, in amounts that exceed federally insured limits. The Company attempts to minimize the risks related to cash, cash equivalents, and marketable securities by investing in a range of financial instruments as defined by the Company. The Company has established guidelines related to credit ratings and maturities intended to safeguard principal balances and maintain liquidity. The marketable securities portfolio is maintained in accordance with the Company's investment policy, which defines allowable investments, specifies credit quality standards and limits the credit exposure of any single issuer. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company is dependent on third-party manufacturers to supply products for commercial and research and development activities associated with its drug and drug candidates, as applicable. In particular, the Company relies and expects to continue to rely on a small number of manufacturers to supply it with its requirements for the active pharmaceutical ingredients and formulated drugs related to the Company's drug and drug candidate activities. These activities, including the commercialization of QINLOCK, could be adversely affected by a significant interruption in the supply of active pharmaceutical ingredients and formulated drugs.
Accounts Receivable	Accounts Receivable Accounts receivable arise from product sales and amounts due from the Company's collaboration partner and have standard payment terms that generally require payment within 30 to 90 days. The amount from product sales represents amounts due from specialty distributors and specialty pharmacies, which are recorded net of reserves for customer chargebacks, trade discounts and allowances, and other incentives to the extent such amounts are payable to the customer by the Company. The Company monitors economic conditions to identify facts or circumstances that may indicate that its receivables are at risk of collection. The Company provides reserves against accounts receivable for estimated losses, if any, that may result from a customer's inability to pay based on the composition of its accounts receivable, current economic conditions, and historical credit loss activity. Amounts determined to be uncollectible are charged or written-off against the reserve. During the years ended December 31, 2023 and 2022, the Company did not record any expected credit losses related to outstanding accounts receivable.
Inventory	Inventory and Cost of Sales Inventories are stated at the lower of cost or estimated net realizable value with cost based on the first-in first-out method. Inventory that can be used in either the production of clinical or commercial products is expensed as research and development costs when identified for use in clinical trials. The Company classifies its inventory costs as long-term when it expects to utilize the inventory beyond its normal operating cycle and includes these costs in long-term investments—restricted and other long-term assets in the consolidated balance sheets. Cost of sales for both product revenues, net and collaboration revenues are based on the sale of inventory used in commercial products. Prior to the regulatory approval of its drug candidates, the Company incurs expenses for the manufacture of drug product supplies to support clinical development that could potentially be available to support the commercial launch of those drugs. Until the date at which initial regulatory approval has been received or is otherwise considered probable, the Company records all such costs as research and development expenses. The Company performs an assessment of the recoverability of capitalized inventories during each reporting period and writes down any excess and obsolete inventory to its net realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded as a component of cost of sales in the Company's consolidated statements of operations and comprehensive loss. The determination of whether inventory costs will be realizable requires the use of estimates by management. If actual market conditions are less favorable than projected by management, additional write-downs of inventory may be required.
Long-Term Investment-Restricted	Long-Term Investment — Restricted The Company's long-term investment—restricted balance is comprised of certificates of deposit. The certificates of deposit are held to secure letters of credit associated with the Company's lease for space at its headquarters location and to secure a credit card. The balances of such accounts are classified as non-current, as the maturities of these instruments are more than one year from the balance sheet date, and are measured at carrying value in the consolidated balance sheets.
Property and Equipment	Property and Equipment Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Asset Category Estimated Useful Life Lab equipment 5 to 7 years Computer equipment 3 to 5 years Furniture and fixtures 7 years Leasehold improvements Shorter of life of lease or 15 years Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the consolidated statements of operations and comprehensive loss. The cost of normal, recurring, or periodic repairs and maintenance activities are expensed as incurred.
Leases	Leases The Company accounts for a contract as a lease when it has the right to control the asset for a period of time while obtaining substantially all of the asset's economic benefits. The Company determines if an arrangement is a lease or contains an embedded lease at inception. For arrangements that meet the definition of a lease, the Company determines the initial classification and measurement of its operating right-of-use asset and operating lease liability at the lease commencement date and thereafter if modified. The lease term includes any renewal options that the Company is reasonably assured to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its estimated secured incremental borrowing rate for that lease term. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance, and other expenses, which are generally referred to as non-lease components. The Company has elected to not separate lease and non-lease components. Only the fixed costs for lease components and their associated non-lease components are accounted for as a single lease component and recognized as part of a right-of-use asset and liability. Rent expense is recognized on a straight-line basis over the reasonably assured lease term based on the total lease payments and is included in operating expenses in the consolidated statements of operations and comprehensive loss. The Company has made an accounting policy election to not recognize short-term leases, or leases that have a lease term of 12 months or less at commencement date, within its consolidated balance sheets and to recognize those lease payments in the consolidated statements of operations and comprehensive loss on a straight-line basis over the lease term. Sublease All of the Company's leases are operating leases. The Company determines the classification of a sublease at inception. If the sublease is determined to be an operating lease, the Company will recognize sublease income on a straight-line basis over the lease term in the consolidated statement of operations and comprehensive loss as a reduction of the related operating expense. If the sublease is determined to be a sales-type lease or direct financing lease, the Company will derecognize the right-of-use asset from the Company's original lease and record a net investment in the sublease and evaluate for impairment. The Company will account for the lease liability of the original lease based on the accounting for a lease liability in a finance lease.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets consist of property, equipment, and operating lease assets. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets or asset group may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends, and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the years ended December 31, 2023, 2022, or 2021.
In Process Research and Development, Policy	Acquired In - Process Research and Development (IPR&D) Acquired IPR&D represents the value assigned to research and development assets that have not reached technological feasibility. Upon the acquisition of IPR&D, the Company completes an assessment of whether the acquisition constitutes the purchase of a single asset or group of assets. The Company considers multiple factors in this assessment, including the nature of the technology acquired, the presence or absence of separate cash flows, the development process and stage of completion, quantitative significance, and the Company's rationale for entering into the transaction. If the Company acquires a business as defined under applicable accounting standards, then the acquired IPR&D is capitalized as an intangible asset on the consolidated balance sheets and recorded at fair value. If the Company acquires an asset or group of assets that do not meet the definition of a business under applicable accounting standards, then the acquired IPR&D is expensed as research and development in the consolidated statements of operations and comprehensive loss on its acquisition date. Future costs to develop these assets are recorded to research and development expense as they are incurred until such time that the asset or group of assets reaches technological feasibility, if ever.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Research and development expenses are comprised of costs incurred in performing research and development activities, including salaries, stock-based compensation and benefits, facility- and technology-related costs, depreciation, manufacturing expenses, external costs of outside vendors engaged to conduct preclinical development activities and trials, and upfront fees paid to third-parties associated with acquired IPR&D that has not reached technological feasibility. Prior to initial regulatory approval, the Company expenses costs relating to the production of inventory for the Company's drug and drug candidates as research and development expenses within the Company's consolidated statements of operations and comprehensive loss in the period incurred, unless the Company believes regulatory approval and subsequent commercialization of the drug candidate is probable and the Company expects the future economic benefit from sales of the drug to be realized. Advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses within the Company's consolidated balance sheets. The prepaid amounts are expensed as the related goods are delivered or the services are performed.
Research Contract Costs and Accruals	Research Contract Costs and Accruals The Company has entered into various research and development contracts with research institutions and other companies. These agreements are generally cancellable, and related payments are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies or trials, including the phase or completion of events, invoices received, and contracted costs. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company's estimates. The Company's historical accrual estimates have not been materially different from the actual costs.
Patent Costs	Patent Costs All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as selling, general, and administrative expenses in the consolidated statements of operations and comprehensive loss.
Stock-Based Compensation	Stock-Based Compensation The Company measures all stock options and other stock-based awards granted to employees and directors based on the fair value on the date of the grant and recognizes compensation expense of those awards over the requisite service period, which is generally the vesting period of the respective award. The straight-line method of expense recognition is applied to all awards with service-only conditions while the graded-vesting method is applied to all awards with both service and performance conditions. The Company has granted performance-based awards under which the fair market value of the awards is expensed after assessing the probability that certain performance criteria will be met and the associated targeted payout level that is forecasted will be achieved. The Company accounts for forfeitures as they occur. The Company classifies stock-based compensation expense in its consolidated statements of operations and comprehensive loss in the same manner in which the award recipient's payroll costs are classified or in which the award recipient's service payments are classified.
Income Taxes	Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company's tax returns. Deferred taxes are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect in the years in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. The Company accounts for uncertainty in income taxes recognized in its consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than- not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties.
Comprehensive Loss	Comprehensive Loss and Accumulated Other Comprehensive Income (Loss) Comprehensive loss includes net loss as well as other changes in stockholders' equity (deficit) that result from transactions and economic events other than those with shareholders. For the years ended December 31, 2023 and 2022, the Company's other comprehensive income (loss) consisted of foreign currency translation adjustments and unrealized gains (losses) on marketable securities. For the year ended December 31, 2021, the Company's other comprehensive income (loss) consisted of unrealized gains (losses) on marketable securities. As of December 31, 2023 and 2022, accumulated other comprehensive income (loss) primarily consisted of foreign currency translation adjustments and unrealized gains (losses) on marketable securities.
Net Loss per Share	Net Loss per Share Basic net income (loss) per share is computed by dividing the net income (loss) by the weighted average number of common shares outstanding, including pre-funded warrants, for the years ended December 31, 2023, 2022, and 2021. Diluted net income (loss) per share is computed by dividing the diluted net income (loss) by the weighted average number of common shares, including potential dilutive common shares assuming the dilutive effect of outstanding stock options and unvested restricted common stock, as determined using the treasury stock method. For periods in which the Company has reported net losses, diluted net loss per common share is the same as basic net loss per common share, since dilutive common shares are not assumed to have been issued if their effect is antidilutive. Potential common shares that are issuable for little or no cash consideration, such as the Company's pre-funded warrants issued in April 2022, are considered outstanding common shares are included in the calculation of basic and diluted net income (loss) per share in all circumstances.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Estimated Useful life of Assets	Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Asset Category Estimated Useful Life Lab equipment 5 to 7 years Computer equipment 3 to 5 years Furniture and fixtures 7 years Leasehold improvements Shorter of life of lease or 15 years

Revenues (Tables)

Revenues (Tables)	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Net product revenues by geography consisted of the following and are attributable to individual countries based on the location of the customer: Year Ended December 31, (in thousands) 2023 2022 2021 U.S. $ 121,546 $ 97,216 $ 81,476 Rest of world 19,570 13,947 5,913 Germany 17,958 14,341 — Total product revenues, net $ 159,074 $ 125,504 $ 87,389
Analysis Of Amount Of And Change In Product Revenue Reserves	Activity in each of the product revenue allowance and reserve categories is summarized as follows: (in thousands) Trade discounts and allowances Chargebacks and administrative fees Government rebates and other incentives Returns Total Balance as of December 31, 2022 $ 475 $ 656 $ 15,825 $ 1,375 $ 18,331 Provision related to sales in the current year 4,529 10,757 17,984 4,636 37,906 Adjustments related to prior period sales (31) — 80 — 49 Credits and payments made during the period (4,219) (10,533) (9,023) (4,916) (28,691) Balance as of December 31, 2023 $ 754 $ 880 $ 24,866 $ 1,095 $ 27,595
Summary Of Total Product Revenue Reserves Included In The Consolidated Balance Sheets	The total reserves described above are summarized as components of the Company's consolidated balance sheets as follows: (in thousands) December 31, 2023 December 31, 2022 Reduction of accounts receivable, net $ 1,528 $ 1,082 Component of accrued expenses and other current liabilities 26,067 17,249 Total revenue-related reserves $ 27,595 $ 18,331

Marketable Securities and Fai_2

Marketable Securities and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Marketable Securities	The following tables present marketable securities by contractual maturity and security type: As of December 31, 2023 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Due within one year: U.S. government securities 97,889 15 (93) $ 97,811 Corporate debt securities 82,934 26 (123) 82,837 Commercial paper 39,542 30 (11) 39,561 Certificates of deposit 2,500 — (1) 2,499 Due after one year through five years: U.S. government securities 31,698 34 (151) 31,581 Corporate debt securities 15,060 64 (5) 15,119 Total $ 269,623 $ 169 $ (384) $ 269,408 As of December 31, 2022 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Due within one year: Corporate debt securities $ 113,939 $ 2 $ (571) $ 113,370 Commercial paper 81,344 12 (336) 81,020 Certificates of deposit 33,877 14 (152) 33,739 U.S. government securities 31,761 15 (160) 31,616 Due after one year through five years: Corporate debt securities 11,278 — (38) 11,240 U.S. government securities 3,349 — (39) 3,310 Total $ 275,548 $ 43 $ (1,296) $ 274,295
Schedule of Financial Assets Measured at Fair Value on a Recurring Basis	The following tables present information about the Company's financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values: As of December 31, 2023 (in thousands) Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ — $ 29,829 $ — $ 29,829 Marketable securities: U.S. government securities — 129,392 — 129,392 Corporate debt securities — 97,956 — 97,956 Commercial paper — 39,561 — 39,561 Certificates of deposit — 2,499 — 2,499 Total $ — $ 299,237 $ — $ 299,237 As of December 31, 2022 (in thousands) Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ — $ 27,787 $ — $ 27,787 Certificates of deposit — 14,167 — 14,167 Corporate debt securities — 4,945 — 4,945 Marketable securities: Corporate debt securities — 124,610 — 124,610 Commercial paper — 81,020 — 81,020 U.S. government securities — 34,926 — 34,926 Certificates of deposit — 33,739 — 33,739 Total $ — $ 321,194 $ — $ 321,194

Inventory (Tables)

Inventory (Tables)	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Schedule of Inventory, Current	Capitalized inventory consisted of the following: (in thousands) December 31, 2023 December 31, 2022 Raw materials $ 4,934 $ 6,844 Work in process 18,253 11,125 Finished goods 2,957 2,592 Total inventory $ 26,144 $ 20,561

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net consisted of the following: December 31, (in thousands) 2023 2022 Laboratory equipment $ 6,517 $ 5,515 Computer equipment 5,035 5,018 Furniture and fixtures 3,922 3,919 Leasehold improvements 2,113 2,113 Construction in progress 31 226 Total cost 17,618 16,791 Less: Accumulated depreciation (12,197) (10,084) Total property and equipment, net $ 5,421 $ 6,707

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Operating Leases in the Consolidated Balance Sheet	All of the Company's leases qualify as operating leases. The following table summarizes the presentation of the Company's operating leases in the consolidated balance sheet: December 31, (in thousands) 2023 2022 Operating lease right of use assets $ 32,073 $ 36,547 Current operating lease liabilities $ 3,504 $ 3,235 Operating lease liabilities, net of current portion 22,375 25,879 Total operating lease liabilities $ 25,879 $ 29,114
Components of Lease Expense	The components of lease expense were as follows: Year Ended December 31, (in thousands) 2023 2022 2021 Operating lease cost $ 6,012 $ 5,809 $ 5,178 Short-term lease cost 60 455 357 Variable lease cost 1,738 1,468 1,225 Sublease income (2,926) (1,736) — Total lease expense, net $ 4,884 $ 5,996 $ 6,760
Summary of Future Annual Minimum Lease Payments Under Operating Leases	Future annual minimum lease payments under operating leases are as follows: (in thousands) As of December 31, 2023 2024 $ 4,854 2025 4,936 2026 5,019 2027 5,101 2028 5,183 Thereafter 5,535 Total future minimum lease payments 30,628 Less: imputed interest (4,749) Total operating lease liabilities $ 25,879
Operating Lease Weighted Average Remaining Term and Discount Rate	The weighted-average remaining lease term and weighted-average discount rate of the Company's operating leases are as follows: As of December 31, 2023 2022 Weighted-average remaining lease term in years 6.08 6.97 Weighted-average discount rate 5.55 % 5.59 %
Schedule of Cash Flow, Supplemental Disclosures, Leases, Lessee	Supplemental disclosure of cash flow information related to the Company's operating leases included in cash flows used in operating activities in the consolidated statement of cash flows were as follows: Year Ended December 31, (in thousands) 2023 2022 2021 Cash paid for amounts included in the measurement of operating lease liabilities $ 4,772 $ 4,617 $ 4,243 Operating lease liabilities arising from obtaining operating lease assets $ — $ 1,188 $ 2,150

Other Consolidated Financial _2

Other Consolidated Financial Detail (Tables)	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	December 31, (in thousands) 2023 2022 External research and development expenses $ 16,095 $ 17,411 Payroll and related expenses 20,519 21,971 Revenue-related reserves 26,067 17,249 Professional fees 5,669 4,275 Other 1,945 3,716 Total accrued expenses and other current liabilities $ 70,295 $ 64,622

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Assumptions used to Determine the Fair Value of Options Granted to Employees and Directors	The assumptions that the Company used to determine the fair value of options granted to employees and directors were as follows, presented on a weighted average basis: Year Ended December 31, 2023 2022 2021 Risk-free interest rate 4.0 % 2.0 % 1.0 % Expected term (in years) 6.0 6.0 5.8 Expected volatility 85.5 % 78.2 % 77.8 % Expected dividend yield 0 % 0 % 0 %
Summary of Option Activity	The following table summarizes the Company's option activity from January 1, 2023 to December 31, 2023: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding as of December 31, 2022 8,279,217 $ 24.26 Granted 1,489,555 $ 15.36 Exercised (190,126) $ 8.42 Forfeited (156,603) $ 22.04 Expired (162,575) $ 36.29 Outstanding as of December 31, 2023 9,259,468 $ 22.98 6.7 $ 27,665 Options vested and expected to vest as of December 31, 2023 9,259,468 $ 22.98 6.7 $ 27,665 Options exercisable as of December 31, 2023 6,879,959 $ 24.96 6.1 $ 20,792
Summary of RSU Activity	The table below summarizes the Company's time-based restricted stock unit activity from January 1, 2023 to December 31, 2023: Number Weighted Unvested at December 31, 2022 2,077,988 $ 18.09 Granted 1,743,194 $ 15.14 Vested (892,882) $ 19.02 Forfeited (393,995) $ 16.92 Unvested at December 31, 2023 2,534,305 $ 15.91 Number Weighted Unvested at December 31, 2022 — $ — Granted 377,949 $ 15.48 Vested (251,971) $ 15.48 Forfeited (5,575) $ 15.48 Unvested at December 31, 2023 120,403 $ 15.48
Classification of Stock-Based Compensation Expense	Stock-based compensation expense was classified in the statements of operations and comprehensive loss as follows: Year Ended December 31, (in thousands) 2023 2022 2021 Research and development $ 21,775 $ 22,238 $ 20,698 Selling, general, and administrative 28,828 29,704 25,380 Total stock-based compensation $ 50,603 $ 51,942 $ 46,078 The following table summarizes share-based compensation expense associated with each of our share-based compensation arrangements: Year Ended December 31, (in thousands) 2023 2022 2021 Stock options $ 26,685 $ 34,861 $ 36,263 Time-based restricted stock units 19,526 16,537 9,047 Performance-based restricted stock units 3,900 — — Employee stock purchase plan 492 544 768 Total stock-based compensation expense $ 50,603 $ 51,942 $ 46,078

Restructuring (Tables)

Restructuring (Tables)	3 Months Ended
	Dec. 31, 2023
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Reserve by Type of Cost	The following table summarized the charges and spending related to the Company’s restructuring efforts during 2021 and 2022: (in thousands) Workforce Reduction Pipeline Programs Total Restructuring charges incurred during the fourth quarter of 2021 $ 9,835 $ 16,335 $ 26,170 Amounts previously included in prepaid and other current assets — (2,927) (2,927) Reserves established 9,835 13,408 23,243 Amounts paid through December 31, 2021 (2,452) — (2,452) Restructuring reserve as of December 31, 2021 $ 7,383 $ 13,408 $ 20,791 Adjustments to previous estimates, net (374) 192 (182) Amounts paid during the year ended December 31, 2022 (7,009) (13,600) (20,609) Restructuring reserve as of December 31, 2022 $ — $ — $ —

Net Loss per Share (Tables)

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Summary of Basic and Diluted Net Loss per Share	Basic and diluted net loss per share was calculated as follows: Year Ended December 31, (in thousands, except share and per share amounts) 2023 2022 2021 Numerator: Net loss $ (194,942) $ (178,931) $ (299,964) Denominator: Weighted average common shares outstanding—basic and diluted 85,059,962 75,500,148 58,084,325 Net loss per share—basic and diluted $ (2.29) $ (2.37) $ (5.16)
Summary of Potential Dilutive Securities	The following potential dilutive securities, presented based on amounts outstanding at the end of each reporting period, have been excluded from the calculation of diluted net loss per share because including them would have had an anti-dilutive impact: As of December 31, 2023 2022 2021 Options to purchase common stock 9,259,468 8,279,217 7,439,508 Unvested restricted stock units 2,534,305 2,077,988 1,537,732 Unvested employee stock purchase plan shares 84,623 61,307 211,822 Total 11,878,396 10,418,512 9,189,062

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	Net loss before income tax expense by jurisdiction is as follows: Year Ended December 31, (in thousands) 2023 2022 2021 U.S. $ (191,378) $ (173,072) $ (281,129) Foreign (3,133) (5,137) (18,835) Net loss before income tax expense $ (194,511) $ (178,209) $ (299,964)
Schedule of Components of Income Tax Expense (Benefit)	The provision for income taxes consisted of the following: Year Ended December 31, (in thousands) 2023 2022 2021 Current provision: Federal $ — $ — $ — State — 166 — Foreign 431 556 — Total current provision 431 722 — Total provision for income taxes $ 431 $ 722 $ —
Reconciliation of U.S. Federal Statutory Income Tax Rate to Effective Income Tax Rate	A reconciliation of the U.S. federal statutory income tax rate to the Company's effective income tax rate is as follows: Year Ended December 31, 2023 2022 2021 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % State taxes, including credits, net of federal benefit 2.4 4.4 3.2 Federal research and orphan drug credit 6.1 4.2 2.5 Stock-based compensation (2.2) (3.6) 0.1 Permanent adjustments and other (1.9) (1.3) (0.3) Increase in deferred tax asset valuation allowance (25.6) (25.1) (26.5) Effective income tax rate (0.2 %) (0.4 %) — %
Schedule of Net Deferred Tax Assets	Net deferred tax assets consisted of the following: December 31, (in thousands) 2023 2022 Deferred tax assets (liabilities): Net operating loss carryforwards $ 210,790 $ 213,710 Research and orphan drug credit carryforwards 59,495 47,418 Stock-based compensation 23,371 20,134 Accrued expenses 7,484 6,944 Operating lease liabilities 7,563 8,699 Property and equipment (149) (131) Operating lease assets (7,042) (8,158) Research and development capitalization 74,551 37,797 Other 1,004 893 Total gross deferred tax assets 377,067 327,306 Valuation allowance (377,067) (327,306) Net deferred tax assets $ — $ —
Schedule of Changes in Valuation Allowance for Deferred Tax Assets	The change in the valuation allowance was as follows: Year Ended December 31, (in thousands) 2023 2022 Valuation allowance as of beginning of year $ (327,306) $ (282,536) Net increases recorded to income tax provision (49,761) (44,770) Valuation allowance as of end of year $ (377,067) $ (327,306)
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the beginning and ending amount of uncertain tax positions is summarized as follows: Year Ended December 31, (in thousands) 2023 2022 Beginning Balance $ 1,857 $ 2,355 Additions based on tax positions for the current period 1,284 635 Additions (reductions) for tax positions of prior periods — (1,133) Ending Balance $ 3,141 $ 1,857

Nature of the Business and Ba_2

Nature of the Business and Basis of Presentation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		12 Months Ended
	Jan. 24, 2023	Apr. 29, 2022	May 31, 2023	Aug. 31, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Apr. 26, 2022
Nature Of Business And Basis Of Presentation [Line Items]
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs	$ 134,500	$ 163,400			$ 149,113	$ 163,353	$ 8,549
Proceeds from pre-funded warrants					$ 24	9	0
Class of Warrant or Right, Outstanding					6,428,270
Net loss					$ (194,942)	(178,931)	$ (299,964)
Accumulated deficit					(1,428,305)	$ (1,233,363)
Cash, cash equivalents and marketable securities					$ 352,900
Common Shares
Nature Of Business And Basis Of Presentation [Line Items]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)	7,986,111	7,501,239			8,990,296	7,501,239	172,094
Convertible preferred shares sold under share purchase agreement (in dollars per share)	$ 18							$ 10
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs					$ 90	$ 75	$ 2
Warrant
Nature Of Business And Basis Of Presentation [Line Items]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)		9,748,761			2,427,693	892,798
Convertible preferred shares sold under share purchase agreement (in dollars per share)								9.99
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 0.01
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs					$ 24	$ 9
Proceeds from pre-funded warrants					$ 100	$ 100
August 2020 Sales Agreement and Amended Sales Agreement
Nature Of Business And Basis Of Presentation [Line Items]
Authorized aggregate offering proceeds				$ 200,000
August 2020 Sales Agreement and Amended Sales Agreement | Common Shares
Nature Of Business And Basis Of Presentation [Line Items]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)					0	0	172,094
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs							$ 8,500
May 2023 Sale Agreement
Nature Of Business And Basis Of Presentation [Line Items]
Authorized aggregate offering proceeds			$ 200,000
Available for future issuance					$ 185,000
May 2023 Sale Agreement | Common Shares
Nature Of Business And Basis Of Presentation [Line Items]
Issuance of common stock sold in public offering, net of underwriting discounts, commissions and offering costs (in shares)					1,004,185
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs					$ 14,600

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Summary of Estimated Useful life of Assets (Details)	Dec. 31, 2023
Lab equipment | Minimum
Property, Plant and Equipment [Line Items]
Property plant and equipment estimated useful lives	5 years
Lab equipment | Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment estimated useful lives	7 years
Computer equipment | Minimum
Property, Plant and Equipment [Line Items]
Property plant and equipment estimated useful lives	3 years
Computer equipment | Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment estimated useful lives	5 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property plant and equipment estimated useful lives	7 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment estimated useful lives	15 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Significant Accounting Policies [Line Items]
Credit losses	$ 0	$ 0	$ 0
Accounts receivable, credit losses	0
Impairment losses on long-lived assets	$ 0	$ 0	$ 0
Minimum
Significant Accounting Policies [Line Items]
Income tax examination, likelihood percentage	50%

Revenues - Net Product Revenues

Revenues - Net Product Revenues by Geography (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenues	$ 163,356	$ 134,036	$ 96,148
Product Revenues, net
Disaggregation of Revenue [Line Items]
Total revenues	159,074	125,504	87,389
Product Revenues, net | U.S.
Disaggregation of Revenue [Line Items]
Total revenues	121,546	97,216	81,476
Product Revenues, net | Rest of world
Disaggregation of Revenue [Line Items]
Total revenues	19,570	13,947	5,913
Product Revenues, net | Germany
Disaggregation of Revenue [Line Items]
Total revenues	$ 17,958	$ 14,341	$ 0

Revenues - Additional Informati

Revenues - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2021	Jun. 30, 2019	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
License Agreement Transactions [Line Items]
Total revenues				$ 163,356,000	$ 134,036,000	$ 96,148,000
Customer One | Revenue from Contract with Customer Benchmark | Customer Concentration Risk
License Agreement Transactions [Line Items]
Concentration risk percentage				44%	40%	57%
Customer One | Reduction of accounts receivable, net | Customer Concentration Risk
License Agreement Transactions [Line Items]
Concentration risk percentage				53%	47%
Customer Two | Revenue from Contract with Customer Benchmark | Customer Concentration Risk
License Agreement Transactions [Line Items]
Concentration risk percentage				12%	12%	18%
Customer Two | Reduction of accounts receivable, net | Customer Concentration Risk
License Agreement Transactions [Line Items]
Concentration risk percentage				16%	15%
Customer Three | Revenue from Contract with Customer Benchmark | Customer Concentration Risk
License Agreement Transactions [Line Items]
Concentration risk percentage						10%
Customer Three | Reduction of accounts receivable, net | Customer Concentration Risk
License Agreement Transactions [Line Items]
Concentration risk percentage					14%
Product Revenues, net
License Agreement Transactions [Line Items]
Total revenues				$ 159,074,000	$ 125,504,000	$ 87,389,000
Product Revenues, net | U.S.
License Agreement Transactions [Line Items]
Total revenues				121,546,000	97,216,000	81,476,000
Product Revenues, net | Rest of world
License Agreement Transactions [Line Items]
Total revenues				19,570,000	13,947,000	5,913,000
Collaboration Arrangement
License Agreement Transactions [Line Items]
Total revenues				$ 4,282,000	$ 8,532,000	$ 8,759,000
Zai License Agreement
License Agreement Transactions [Line Items]
Collaboration arrangement transaction price		$ 5,000,000
Agreement continuation period	10 years
Zai License Agreement | Development And Commercial Milestone | Maximum
License Agreement Transactions [Line Items]
License agreement milestone	$ 173,000,000
Zai License Agreement | Development Milestone | Collaboration Arrangement
License Agreement Transactions [Line Items]
Total revenues	12,000,000
Zai License Agreement | Development Milestone | Maximum
License Agreement Transactions [Line Items]
License agreement milestone	38,000,000
Zai License Agreement | Commercial Milestone | Maximum
License Agreement Transactions [Line Items]
License agreement milestone	$ 135,000,000
Zai License Agreement | Upfront Payment | Collaboration Arrangement
License Agreement Transactions [Line Items]
Total revenues			$ 20,000,000

Revenues - Product Revenue Allo

Revenues - Product Revenue Allowance and Reserve Categories (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 18,331
Provision related to sales in the current year	37,906
Adjustments related to prior period sales	49
Credits and payments made during the period	(28,691)
Ending balance	27,595
Trade discounts and allowances
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	475
Provision related to sales in the current year	4,529
Adjustments related to prior period sales	(31)
Credits and payments made during the period	(4,219)
Ending balance	754
Chargebacks and administrative fees
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	656
Provision related to sales in the current year	10,757
Adjustments related to prior period sales	0
Credits and payments made during the period	(10,533)
Ending balance	880
Government rebates and other incentives
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	15,825
Provision related to sales in the current year	17,984
Adjustments related to prior period sales	80
Credits and payments made during the period	(9,023)
Ending balance	24,866
Returns
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	1,375
Provision related to sales in the current year	4,636
Adjustments related to prior period sales	0
Credits and payments made during the period	(4,916)
Ending balance	$ 1,095

Revenues - Total Reserves Summa

Revenues - Total Reserves Summarized (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Total revenue-related reserves	$ 27,595	$ 18,331
Reduction of accounts receivable, net
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Total revenue-related reserves	1,528	1,082
Component of accrued expenses and other current liabilities
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Total revenue-related reserves	$ 26,067	$ 17,249

Marketable Securities and Fai_3

Marketable Securities and Fair Value Measurements - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Total
Amortized Cost	$ 269,623	$ 275,548
Gross Unrealized Gains	169	43
Gross Unrealized Losses	(384)	(1,296)
Estimated Fair Value	269,408	274,295
U.S. government securities
Due within one year:
Amortized Cost	97,889	31,761
Gross Unrealized Gains	15	15
Gross Unrealized Losses	93	160
Estimated Fair Value	97,811	31,616
Due after one year through five years:
Amortized Cost	31,698	3,349
Gross Unrealized Gains	34	0
Gross Unrealized Losses	(151)	(39)
Estimated Fair Value	31,581	3,310
Total
Estimated Fair Value	129,392	34,926
Corporate debt securities
Due within one year:
Amortized Cost	82,934	113,939
Gross Unrealized Gains	26	2
Gross Unrealized Losses	123	571
Estimated Fair Value	82,837	113,370
Due after one year through five years:
Amortized Cost	15,060	11,278
Gross Unrealized Gains	64	0
Gross Unrealized Losses	(5)	(38)
Estimated Fair Value	15,119	11,240
Total
Estimated Fair Value	39,561	124,610
Commercial paper
Due within one year:
Amortized Cost	39,542	81,344
Gross Unrealized Gains	30	12
Gross Unrealized Losses	11	336
Estimated Fair Value	39,561	81,020
Total
Estimated Fair Value	97,956	81,020
Certificates of deposit
Due within one year:
Amortized Cost	2,500	33,877
Gross Unrealized Gains	0	14
Gross Unrealized Losses	1	152
Estimated Fair Value	2,499	33,739
Total
Estimated Fair Value	$ 2,499	$ 33,739

Marketable Securities and Fai_4

Marketable Securities and Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Marketable securities:
Total Marketable securities	$ 269,408	$ 274,295
Total	299,237	321,194
U.S. government securities
Marketable securities:
Total Marketable securities	129,392	34,926
Commercial paper
Marketable securities:
Total Marketable securities	97,956	81,020
Corporate debt securities
Marketable securities:
Total Marketable securities	39,561	124,610
Certificates of deposit
Marketable securities:
Total Marketable securities	2,499	33,739
Money market funds
Cash equivalents:
Total Cash equivalents	29,829	27,787
Certificates of deposit
Cash equivalents:
Total Cash equivalents		14,167
Corporate debt securities
Cash equivalents:
Total Cash equivalents		4,945
Level 1
Marketable securities:
Total	0	0
Level 1 | U.S. government securities
Marketable securities:
Total Marketable securities	0	0
Level 1 | Commercial paper
Marketable securities:
Total Marketable securities	0	0
Level 1 | Corporate debt securities
Marketable securities:
Total Marketable securities	0	0
Level 1 | Certificates of deposit
Marketable securities:
Total Marketable securities	0	0
Level 1 | Money market funds
Cash equivalents:
Total Cash equivalents	0	0
Level 1 | Certificates of deposit
Cash equivalents:
Total Cash equivalents		0
Level 1 | Corporate debt securities
Cash equivalents:
Total Cash equivalents		0
Level 2
Marketable securities:
Total	299,237	321,194
Level 2 | U.S. government securities
Marketable securities:
Total Marketable securities	129,392	34,926
Level 2 | Commercial paper
Marketable securities:
Total Marketable securities	97,956	81,020
Level 2 | Corporate debt securities
Marketable securities:
Total Marketable securities	39,561	124,610
Level 2 | Certificates of deposit
Marketable securities:
Total Marketable securities	2,499	33,739
Level 2 | Money market funds
Cash equivalents:
Total Cash equivalents	29,829	27,787
Level 2 | Certificates of deposit
Cash equivalents:
Total Cash equivalents		14,167
Level 2 | Corporate debt securities
Cash equivalents:
Total Cash equivalents		4,945
Level 3
Marketable securities:
Total	0	0
Level 3 | U.S. government securities
Marketable securities:
Total Marketable securities	0	0
Level 3 | Commercial paper
Marketable securities:
Total Marketable securities	0	0
Level 3 | Corporate debt securities
Marketable securities:
Total Marketable securities	0	0
Level 3 | Certificates of deposit
Marketable securities:
Total Marketable securities	0	0
Level 3 | Money market funds
Cash equivalents:
Total Cash equivalents	$ 0	0
Level 3 | Certificates of deposit
Cash equivalents:
Total Cash equivalents		0
Level 3 | Corporate debt securities
Cash equivalents:
Total Cash equivalents		$ 0

Marketable Securities and Fai_5

Marketable Securities and Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Letter of Credit | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash balance held to secure letter of credit associated with lease and Company credit card	$ 3.1	$ 3.1

Inventory (Details)

Inventory (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Inventory Disclosure [Abstract]
Raw materials	$ 4,934,000	$ 6,844,000
Work in process	18,253,000	11,125,000
Finished goods	2,957,000	2,592,000
Total inventory	26,144,000	20,561,000
Inventory, noncurrent	4,900,000
Inventory write-down	$ 0	$ 900,000	$ 100,000

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total cost	$ 17,618	$ 16,791
Less: Accumulated depreciation	(12,197)	(10,084)
Total property and equipment, net	5,421	6,707
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total cost	6,517	5,515
Computer equipment
Property, Plant and Equipment [Line Items]
Total cost	5,035	5,018
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total cost	3,922	3,919
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total cost	2,113	2,113
Construction in progress
Property, Plant and Equipment [Line Items]
Total cost	$ 31	$ 226

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 2,100	$ 2,946	$ 3,014

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	1 Months Ended
	Aug. 31, 2020 renewal_option	Apr. 30, 2019 USD ($) ft² renewal_option	May 31, 2018 USD ($) renewal_option	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	May 31, 2022 USD ($) ft²	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease assets				$ 32,073	$ 36,547
Operating lease liability				25,879	29,114
Operating sublease area | ft²							44,343
Lessor, Operating Sublease, Term							3 years
Lessor, Operating Lease, Payments to be Received							$ 8,900
The Initial Space
Lessee, Lease, Description [Line Items]
Number of lease options | renewal_option			2
Lease renewal term			5 years
Initial annual base rent			$ 2,000
Initial annual base rent increase			$ 22,400
The Additional Space
Lessee, Lease, Description [Line Items]
Number of lease options | renewal_option		2
Lease renewal term		5 years
Initial annual base rent		$ 1,900
Initial annual base rent increase		$ 18,200
Additional office space | ft²		38,003
The Premises
Lessee, Lease, Description [Line Items]
Operating lease area | ft²		82,346
Letter of Credit | Certificates of deposit
Lessee, Lease, Description [Line Items]
Cash balance to secure letter of credit associated with lease				3,100	3,100
Letter of Credit | The Premises | Certificates of deposit
Lessee, Lease, Description [Line Items]
Cash balance to secure letter of credit associated with lease				$ 2,100	$ 2,100
Kansas
Lessee, Lease, Description [Line Items]
Number of lease options | renewal_option	2
Lease renewal term	5 years
Operating lease assets						$ 3,800		$ 3,400	$ 500
Operating lease liability						$ 1,100		$ 1,700	$ 500

Leases - Operating Leases in th

Leases - Operating Leases in the Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating lease assets	$ 32,073	$ 36,547
Operating lease liabilities	3,504	3,235
Operating lease liabilities, net of current portion	22,375	25,879
Total operating lease liabilities	$ 25,879	$ 29,114

Leases - Components of Lease Ex

Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease cost	$ 6,012	$ 5,809	$ 5,178
Short-term lease cost	60	455	357
Variable lease cost	1,738	1,468	1,225
Sublease income	(2,926)	(1,736)	0
Total lease expense, net	$ 4,884	$ 5,996	$ 6,760

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Lease Payments under Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Operating Leases, After Adoption
2024	$ 4,854
2025	4,936
2026	5,019
2027	5,101
2028	5,183
Thereafter	5,535
Total future minimum lease payments	30,628
Less: imputed interest	(4,749)
Total operating lease liabilities	$ 25,879	$ 29,114

Leases - Operating Lease Weight

Leases - Operating Lease Weighted Average Remaining Term and Discount Rate (Details)	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Weighted-average remaining lease term in years	6 years 29 days	6 years 11 months 19 days
Weighted-average discount rate	5.55%	5.59%

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 4,772	$ 4,617	$ 4,243
Operating lease liabilities arising from obtaining operating lease assets	$ 0	$ 1,188	$ 2,150

Other Consolidated Financial _3

Other Consolidated Financial Detail - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accounts Payable and Accrued Liabilities [Abstract]
External research and development expenses	$ 16,095	$ 17,411
Payroll and related expenses	20,519	21,971
Revenue-related reserves	27,595	18,331
Professional fees	5,669	4,275
Other	1,945	3,716
Total accrued expenses and other current liabilities	$ 70,295	$ 64,622

Other Consolidated Financial _4

Other Consolidated Financial Detail - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Interest income	$ 16.7	$ 5.1	$ 0.6

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		12 Months Ended
	Jan. 24, 2023	Apr. 29, 2022	May 31, 2023	Aug. 31, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Apr. 26, 2022
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)					5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)					0
Preferred stock, shares issued (in shares)					0
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs	$ 134,500	$ 163,400			$ 149,113	$ 163,353	$ 8,549
Proceeds from pre-funded warrants					$ 24	$ 9	$ 0
Common Shares
Class of Stock [Line Items]
Number of additional shares issued and sold (in shares)	7,986,111	7,501,239			8,990,296	7,501,239	172,094
Convertible preferred shares sold under share purchase agreement (in dollars per share)	$ 18							$ 10
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs					$ 90	$ 75	$ 2
Warrant
Class of Stock [Line Items]
Number of additional shares issued and sold (in shares)		9,748,761			2,427,693	892,798
Convertible preferred shares sold under share purchase agreement (in dollars per share)								9.99
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 0.01
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs					$ 24	$ 9
Proceeds from pre-funded warrants					$ 100	$ 100
August 2020 Sales Agreement and Amended Sales Agreement
Class of Stock [Line Items]
Authorized aggregate offering proceeds				$ 200,000
August 2020 Sales Agreement and Amended Sales Agreement | Common Shares
Class of Stock [Line Items]
Number of additional shares issued and sold (in shares)					0	0	172,094
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs							$ 8,500
May 2023 Sale Agreement
Class of Stock [Line Items]
Authorized aggregate offering proceeds			$ 200,000
Available for future issuance					$ 185,000
May 2023 Sale Agreement | Common Shares
Class of Stock [Line Items]
Number of additional shares issued and sold (in shares)					1,004,185
Issuance of common stock and pre-funded warrants, net of underwriting discounts, commissions and offering costs					$ 14,600

Stock-Based Awards - Additional

Stock-Based Awards - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended	12 Months Ended
	Feb. 06, 2024	Jan. 01, 2024	Sep. 21, 2017	Feb. 28, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued under ESPP (in shares)					113,019	148,619,000,000	90,947,000,000
Intrinsic value of stock options exercised					$ 1,000	$ 400	$ 15,700
Weighted average grant-date fair value per share of options granted (in dollars per share)					$ 11.30	$ 6.48	$ 17.95
Unrecognized compensation cost related to unvested share-based awards					$ 54,500
Unrecognized compensation cost related to unvested share-based awards, period for recognition					2 years
Stock-based compensation expense					$ 50,603	$ 51,942	$ 46,078
Time-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, granted (in shares)					1,743,194
Fair-value of units					$ 14,700	$ 6,200	4,700
Vested (in shares)					892,882
Nonvested shares outstanding (in shares)					2,534,305	2,077,988
Stock-based compensation expense					$ 19,526	$ 16,537	$ 9,047
Time-based restricted stock units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period					4 years	4 years	4 years
Time-based restricted stock units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period					1 year	1 year	1 year
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, granted (in shares)					377,949	0	0
Fair-value of units					$ 3,200
Vested (in shares)					251,971	0	0
Nonvested shares outstanding (in shares)					120,403	0	0
Stock-based compensation expense					$ 3,900	$ 0	$ 0
Unvested employee stock purchase plan shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value of common stock					85%
Discount percentage					15%
Purchase period					6 months
Stock-based compensation expense					$ 492	$ 544	$ 768
2017 Stock Option and Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)					10 years
2017 Stock Option and Incentive Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value of common stock					100%
2017 Stock Option and Incentive Plan | Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period					1 year
2017 Stock Option and Incentive Plan | Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period					4 years
Common Shares | 2017 Stock Option and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares reserved for issuance (in shares)			2,655,831		1,471,244
Effective date from which automatic annual increase in number of shares reserved for future issuance			Jan. 01, 2018
Percentage of automatic annual increase in number of shares reserved for future issuance			4%
Common Shares | 2017 Stock Option and Incentive Plan | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved for issuance (in shares)		3,220,133
Common Shares | 2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares reserved for issuance (in shares)			306,750		2,219,550
Effective date from which automatic annual increase in number of shares reserved for future issuance			Jan. 01, 2018
Date until which automatic annual increase in number of shares reserved for future issuance			Jan. 01, 2027
Common Shares | 2017 Employee Stock Purchase Plan | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved for issuance (in shares)		400,000
Common Shares | 2017 Employee Stock Purchase Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of automatic annual increase in number of shares reserved for future issuance			1%
Automatic annual increase in number of shares reserved for future issuance (in shares)			400,000
Common Shares | Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares reserved for issuance (in shares)					444,400			800,000
Increase in shares reserved for issuance (in shares)				270,000
Common Shares | Inducement Plan | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved for issuance (in shares)	355,600

Stock-Based Awards - Summary of

Stock-Based Awards - Summary of Assumptions used to Determine the Fair Value of Options Granted to Employees and Directors (Details) - Stock options	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4%	2%	1%
Expected term (in years)	6 years	6 years	5 years 9 months 18 days
Expected volatility	85.50%	78.20%	77.80%
Expected dividend yield	0%	0%	0%

Stock-Based Awards - Summary _2

Stock-Based Awards - Summary of Option Activity (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares shares
Number of Shares
Outstanding, beginning balance, number of shares (in shares) | shares	8,279,217
Granted | shares	1,489,555
Exercised | shares	(190,126)
Forfeited | shares	(156,603)
Expired | shares	(162,575)
Outstanding, ending balance, number of shares (in shares) | shares	9,259,468
Options vested and expected to vest (in shares) | shares	9,259,468
Options exercisable (in shares) | shares	6,879,959
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 24.26
Granted (in dollars per share) | $ / shares	15.36
Exercised (in dollars per share) | $ / shares	8.42
Forfeited (in dollars per share) | $ / shares	22.04
Expired (in dollars per share) | $ / shares	36.29
Outstanding, ending balance (in dollars per share) | $ / shares	22.98
Options vested and expected to vest (in dollars per share) | $ / shares	22.98
Options exercisable (in dollars per share) | $ / shares	$ 24.96
Additional Disclosures
Outstanding, weighted average remaining contractual term	6 years 8 months 12 days
Options vested and expected to vest, weighted average remaining contractual term	6 years 8 months 12 days
Options exercisable, weighted average remaining contractual term	6 years 1 month 6 days
Outstanding, aggregate intrinsic value | $	$ 27,665
Options vested and expected to vest, aggregate intrinsic value | $	27,665
Options exercisable, aggregate intrinsic value | $	$ 20,792

Stock-Based Awards - Summary _3

Stock-Based Awards - Summary of RSU Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Time-based restricted stock units
Number of Shares
Outstanding shares, beginning balance (in shares)	2,077,988
Granted (in shares)	1,743,194
Vested (in shares)	(892,882)
Forfeited (in shares)	(393,995)
Outstanding shares, ending balance (in shares)	2,534,305	2,077,988
Weighted Average Exercise Price
Weighted average grant date fair value, beginning balance (in dollars per share)	$ 18.09
Weighted average grant date fair value, granted (in dollars per share)	15.14
Weighted average grant date fair value, vested (in dollars per share)	19.02
Weighted average grant date fair value, forfeited (in dollars per share)	16.92
Weighted average grant date fair value, ending balance (in dollars per share)	$ 15.91	$ 18.09
Performance-based restricted stock units
Number of Shares
Outstanding shares, beginning balance (in shares)	0	0
Granted (in shares)	377,949	0	0
Vested (in shares)	(251,971)	0	0
Forfeited (in shares)	(5,575)
Outstanding shares, ending balance (in shares)	120,403	0	0
Weighted Average Exercise Price
Weighted average grant date fair value, beginning balance (in dollars per share)	$ 0
Weighted average grant date fair value, granted (in dollars per share)	15.48
Weighted average grant date fair value, vested (in dollars per share)	15.48
Weighted average grant date fair value, forfeited (in dollars per share)	15.48
Weighted average grant date fair value, ending balance (in dollars per share)	$ 15.48	$ 0

Stock-Based Awards - Classifica

Stock-Based Awards - Classification of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 50,603	$ 51,942	$ 46,078
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	21,775	22,238	20,698
Selling, general, and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	28,828	29,704	25,380
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	26,685	34,861	36,263
Time-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	19,526	16,537	9,047
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	3,900	0	0
Performance-based restricted stock units | Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	1,000
Performance-based restricted stock units | Selling, general, and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	2,900
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 492	$ 544	$ 768

Business Combinations and Asset

Business Combinations and Asset Acquisitions (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Asset Acquisition [Line Items]
Acquired in-process research and development		$ 0	$ 0	$ 4,000,000
License | Sprint Bioscience
Asset Acquisition [Line Items]
Acquired in-process research and development	$ 4,000,000

401(k) Savings Plan - Additiona

401(k) Savings Plan - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan description	Effective January 1, 2018, the Company adopted the 2018 401(k) Plan, a defined contribution plan under Section 401(k) of the Internal Revenue Code, whereby the Company provides matching contributions of 100% of each employee's contribution up to a maximum matching contribution of 3% of the employee's eligible compensation and at a rate of 50% of each employee's contribution in excess of 3% up to a maximum of 5% of the employee's eligible compensation.
Matching contributions to the plan by employer	$ 2.4	$ 2.7	$ 2.8
Up to Three Percent of Compensation
Defined Contribution Plan Disclosure [Line Items]
Percentage of matching contribution to plan	100%
Three to Five Percent of Compensation
Defined Contribution Plan Disclosure [Line Items]
Percentage of matching contribution to plan	50%
Maximum | First Tier of Matching
Defined Contribution Plan Disclosure [Line Items]
Employee earnings subject to employer match	3%
Maximum | Second Tier of Matching
Defined Contribution Plan Disclosure [Line Items]
Percentage of salary for matching contribution per employee on time-based vesting	5%
Minimum | Second Tier of Matching
Defined Contribution Plan Disclosure [Line Items]
Percentage of salary for matching contribution per employee on time-based vesting	3%

Restructuring (Details)

Restructuring (Details) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Dec. 31, 2021 USD ($)	Nov. 30, 2021 USD ($) position	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent		35%
Restructuring and Related Cost, Number of Positions Eliminated | position		140
Restructuring Charges			$ 26,170
Restructuring Costs and Asset Impairment Charges			(2,927)
Restructuring Reserve	$ 20,791	$ 23,243	20,791	$ 0	$ 20,791
Payments for Restructuring	(2,452)			(20,609)
Restructuring Reserve, Accrual Adjustment				(182)
Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring Charges					22,200
Selling, general, and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring Charges					4,000
Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			9,835
Restructuring Costs and Asset Impairment Charges			0
Restructuring Reserve	7,383	9,835	7,383	0	7,383
Payments for Restructuring	(2,452)			(7,009)
Restructuring Reserve, Accrual Adjustment				(374)
Pipeline programs
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			16,335
Restructuring Costs and Asset Impairment Charges			(2,927)
Restructuring Reserve	13,408	$ 13,408	$ 13,408	0	$ 13,408
Payments for Restructuring	$ 0			(13,600)
Restructuring Reserve, Accrual Adjustment				$ 192

Net Loss per Share - Summary of

Net Loss per Share - Summary of Basic and Diluted Net Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net loss	$ (194,942)	$ (178,931)	$ (299,964)
Denominator:
Weighted average common shares outstanding - diluted (in shares)	85,059,962	75,500,148	58,084,325
Weighted average common shares outstanding - basic (in shares)	85,059,962	75,500,148	58,084,325
Net loss per share - diluted (in dollars per share)	$ (2.29)	$ (2.37)	$ (5.16)
Net loss per share - basic (in dollars per share)	$ (2.29)	$ (2.37)	$ (5.16)

Net Loss per Share - Summary _2

Net Loss per Share - Summary of Potential Dilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from computation of diluted net loss per common share (in shares)	11,878,396	10,418,512	9,189,062
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from computation of diluted net loss per common share (in shares)	9,259,468	8,279,217	7,439,508
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from computation of diluted net loss per common share (in shares)	2,534,305	2,077,988	1,537,732
Unvested employee stock purchase plan shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from computation of diluted net loss per common share (in shares)	84,623	61,307	211,822

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details)		12 Months Ended
	Oct. 02, 2017	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Income Tax Disclosure [Line Items]
Conversion ratio	5.65
Increase (Decrease) in Deferred Income Taxes			$ 800,000
Tax Cuts and Jobs Act, capitalized research and development costs		$ 223,400,000	176,900,000
Research and orphan drug credit carryforwards		$ 59,495,000	47,418,000
Income tax examination, description		There are currently no pending income tax examinations. The Company's tax years that are open under statute are from December 31, 2020 to the present, although carryforward attributes that were generated prior to 2020 may still be adjusted upon examination by the IRS or state tax authorities if they either have been or will be used in a future period.
Accrued interest or penalties related to uncertain tax positions		$ 0	0
Income Tax Examination, Penalties and Interest Expense		$ 0	$ 0
Federal
Income Tax Disclosure [Line Items]
Tax Cuts and Jobs Act, capitalized research and development costs amortization period		5 years
Net operating loss carryforwards		$ 827,300,000
Research and orphan drug credit carryforwards		$ 55,700,000
Tax credit carryforwards expiration year		2037
State
Income Tax Disclosure [Line Items]
Net operating loss carryforwards		$ 733,400,000
Net operating loss carryforwards expiration year		2027
Research and orphan drug credit carryforwards		$ 4,800,000
Tax credit carryforwards expiration year		2032
Foreign Tax Authority
Income Tax Disclosure [Line Items]
Tax Cuts and Jobs Act, capitalized research and development costs amortization period		15 years
Net operating loss carryforwards		$ 29,800,000
Tax credit carryforwards expiration year		2026

Income Taxes - Schedule of Net

Income Taxes - Schedule of Net Loss Domestic and Foreign (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
U.S.	$ (191,378)	$ (173,072)	$ (281,129)
Foreign	(3,133)	(5,137)	(18,835)
Loss before income tax expense	$ (194,511)	$ (178,209)	$ (299,964)

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current provision:
Federal	$ 0	$ 0	$ 0
State	0	166	0
Foreign	431	556	0
Total current provision	431	722	0
Total provision for income taxes	$ 431	$ 722	$ 0

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of U.S. Federal Statutory Income Tax Rate to Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21%	21%	21%
State taxes, including credits, net of federal benefit	2.40%	4.40%	3.20%
Federal research and orphan drug credit	6.10%	4.20%	2.50%
Stock-based compensation	(2.20%)	(3.60%)	0.10%
Permanent adjustments and other	(1.90%)	(1.30%)	(0.30%)
Increase in deferred tax asset valuation allowance	(25.60%)	(25.10%)	(26.50%)
Effective income tax rate	(0.20%)	(0.40%)	0%

Income Taxes - Schedule of Ne_2

Income Taxes - Schedule of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets (liabilities):
Net operating loss carryforwards	$ 210,790	$ 213,710
Research and orphan drug credit carryforwards	59,495	47,418
Stock-based compensation	23,371	20,134
Accrued expenses	7,484	6,944
Operating lease liabilities	7,563	8,699
Property and equipment	(149)	(131)
Operating lease assets	(7,042)	(8,158)
Research and development capitalization	74,551	37,797
Other	1,004	893
Total gross deferred tax assets	377,067	327,306
Valuation allowance	(377,067)	(327,306)	$ (282,536)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Schedule of Chan

Income Taxes - Schedule of Changes in Valuation Allowance for Deferred Tax Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Valuation allowance as of beginning of year	$ (327,306)	$ (282,536)
Net increases recorded to income tax provision	(49,761)	(44,770)
Valuation allowance as of end of year	$ (377,067)	$ (327,306)

Income Taxes - Schedule of Unre

Income Taxes - Schedule of Unrecognized Tax Benefits Roll Forward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 1,857	$ 2,355
Additions based on tax positions for the current period	1,284	635
Additions (reductions) for tax positions of prior periods	0	(1,133)
Ending Balance	$ 3,141	$ 1,857

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - Supply Commitment - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Commitments [Line Items]
Supply commitment, remaining minimum amount committed	$ 11
Supply commitment payment period, year one	1 year
Supply commitment amount paid	$ 10	$ 9.6	$ 9.1