Day One Biopharmaceuticals (DAWN) 10-K 6 Mar 23 2022 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Mar. 01, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Entity Registrant Name	DAY ONE BIOPHARMACEUTICALS, INC.
Entity Central Index Key	0001845337
Entity File Number	001-40431
Entity Tax Identification Number	83-2415215
Entity Incorporation, State or Country Code	DE
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Shell Company	false
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Entity Address, Address Line One	2000 Sierra Point Parkway
Entity Address, Address Line Two	Suite 501
Entity Address, City or Town	Brisbane
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94005
City Area Code	650
Local Phone Number	484-0899
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	DAWN
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		73,587,094
Entity Public Float			$ 697.9
Documents Incorporated by Reference	Portions of the registrant’s Definitive Proxy Statement relating to the 2023 Annual Meeting of Shareholders are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein. The Definitive Proxy Statement will be filed within 120 days of the Registrant’s fiscal year ended December 31, 2022. Except with respect to information specifically incorporated by reference in this Form 10-K, the Proxy Statement is not deemed to be filed as part of this Form 10-K.
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	San Mateo, California

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 85,262	$ 284,309
Short-term investments	257,007	0
Prepaid expenses and other current assets	5,605	5,059
Total current assets	347,874	289,368
Property and equipment, net	20	57
Operating lease right-of-use asset	699	227
Deposits and other long-term assets	469	169
Total assets	349,062	289,821
Current liabilities:
Accounts payable	260	1,744
Accrued expenses and other current liabilities	15,950	6,709
Current portion of operating lease liabilities	405	204
Total current liabilities	16,615	8,657
Long-term portion of lease liabilities	408	16
Total liabilities	17,023	8,673
Commitments and contingencies (Note 6)
Stockholders' equity
Common stock, $0.0001 par value; 500,000,000 shares authorized as of December 31, 2022 and 2021; 73,458,176 and 61,952,292 shares issued and outstanding as of December 31, 2022 and 2021, respectively	7	6
Additional paid-in-capital	601,771	408,629
Accumulated other comprehensive loss	(71)	0
Accumulated deficit	(269,668)	(127,487)
Total stockholders' equity	332,039	281,148
Total liabilities and stockholders' equity	$ 349,062	$ 289,821

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Common Stock, Par or Stated Value Per Share	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Shares, Issued	73,458,176	61,952,292
Common Stock, Shares, Outstanding	73,458,176	61,952,292

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating expenses:
Research and development	$ 85,618	$ 43,584	$ 9,100
General and administrative	61,291	29,159	4,682
Total operating expenses	146,909	72,743	13,782
Loss from operations	(146,909)	(72,743)	(13,782)
Interest income (expense), net	4,746	4	(30)
Other expense, net	(18)	(15)	(31)
Changes in fair value of derivative tranche liability	0	0	(30,000)
Net loss	(142,181)	(72,754)	(43,843)
Net loss attributable to redeemable convertible noncontrolling interests	0	(2,109)	(3,336)
Exchange of redeemable noncontrolling interest shares-deemed dividend	0	(99,994)	0
Net loss attributable to common stockholders/members	$ (142,181)	$ (170,639)	$ (40,507)
Net loss per share, basic	$ (2.17)	$ (4.62)	$ (7.33)
Net loss per share, diluted	$ (2.17)	$ (4.62)	$ (7.33)
Weighted-average number of common shares used in computing net loss per share, basic	65,466,773	36,960,569	5,529,519
Weighted-average number of common shares used in computing net loss per share, diluted	65,466,773	36,960,569	5,529,519

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Net loss	$ (142,181)	$ (72,754)	$ (43,843)
Other comprehensive loss:
Unrealized loss on available-for-sale securities	(71)	0	0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent, Total	$ (142,252)	$ (72,754)	$ (43,843)

Consolidated Statements of Rede

Consolidated Statements of Redeemable Convertible Preferred Shares, Redeemable Noncontrolling Interest and Stockholders Equity/ Members (Deficit) - USD ($) $ in Thousands	Total	Common Stock [Member]	Preferred Stock [Member] Redeemable Convertible Preferred Stock [Member]	Common Shares [Member]	Incentive Shares [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Redeemable Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2019	$ (10,673)		$ 30,504	$ 2,000	$ 111		$ (12,784)		$ 5,487
Beginning Balance (In shares) at Dec. 31, 2019			12,502,752	6,035,869	1,488,421
Issuance of Series A redeemable convertible preferred shares for cash net of issuance costs of $95 and derivative tranches liability of $1,483			$ 29,977
Issuance of Series A redeemable convertible preferred shares, shares			10,348,505
Issuance of incentive shares, shares					3,101,178
Cancellations of incentive shares, shares					(477,582)
Reclassification of derivative tranches liability upon settlement			$ 31,483
Share-based compensation expense	526				$ 526
Net loss attributable to redeemable convertible noncontrolling interests	(3,336)								(3,336)
Transfer to redeemable noncontrolling interest related to change in ownership	(3,551)						(3,551)		3,551
Net loss attributable to Day One Biopharmaceuticals Holding Company, LLC members	(40,507)						(40,507)
Unrealized loss on available-for-sale securities	0
Ending Balance at Dec. 31, 2020	(54,205)		$ 91,964	$ 2,000	$ 637		(56,842)		5,702
Ending Balance (In shares) at Dec. 31, 2020			22,851,257	6,035,869	4,112,017
Issuance of Series A redeemable convertible preferred shares for cash net of issuance costs of $95 and derivative tranches liability of $1,483			$ 129,757
Issuance of Series A redeemable convertible preferred shares, shares			9,638,141
Issuance of incentive shares, shares					2,959,795
Cancellations of incentive shares, shares					(265,596)
Conversion of redeemable convertible preferred, common, and incentive shares into common stock	221,721	$ 4	$ (221,721)	$ (2,000)	$ (1,175)	$ 224,892
Conversion of redeemable convertible preferred, common, and incentive shares into common stock, Shares		43,958,557	(32,489,398)	(6,035,869)	(6,806,216)
Conversion of redeemable noncontrolling interest to common stock	3,593	$ 1				3,592			(3,593)
Conversion Of Redeemable Noncontrolling Interest To Common Stock Shares		6,470,382
Common stock issued in IPO, net of issuance costs of $16,995	167,045	$ 1				167,044
Common stock issued in IPO, net of issuance costs of $16,995, shares		11,500,000
Issuance of shares pursuant to Employee Stock Purchase Plan	318					318
Issuance of shares pursuant to Employee Stock Purchase Plan, Shares		23,353
Net loss attributable to common stockholders/members	(70,645)						(70,645)
Share-based compensation expense	13,321				$ 538	12,783
Net loss attributable to redeemable convertible noncontrolling interests	(2,109)								$ (2,109)
Stock Issued During Period, Shares, Conversion of Units		43,958,557	(32,489,398)	(6,035,869)	(6,806,216)
Unrealized loss on available-for-sale securities	0
Ending Balance at Dec. 31, 2021	281,148	$ 6				408,629	(127,487)
Ending Balance (In shares) at Dec. 31, 2021		61,952,292
Issuance of shares pursuant to Employee Stock Purchase Plan	642					642
Issuance of shares pursuant to Employee Stock Purchase Plan, Shares				97,413
Net loss attributable to common stockholders/members	(142,181)						(142,181)
Share-based compensation expense	27,242					27,242
Net loss attributable to redeemable convertible noncontrolling interests	0
Issuance of common stock upon exercise of stock options, shares		235,474
Issuance of common stock upon exercise of stock options, Amount	3,649					3,649
Issuance of common stock upon release of restricted stock units, shares		79,441
Common stock issued pursuant to follow-on offering, net of issuance costs, Shares				11,500,000
Common stock issued pursuant to follow-on offering, net of issuance costs, Amount	161,610			$ 1		161,609
Unvested common stock forfeiture, shares				406,444
Unrealized loss on available-for-sale securities	(71)							$ (71)
Ending Balance at Dec. 31, 2022	$ 332,039	$ 7				$ 601,771	$ (269,668)	$ 71
Ending Balance (In shares) at Dec. 31, 2022		73,458,176

Consolidated Statements of Re_2

Consolidated Statements of Redeemable Convertible Preferred Shares, Redeemable Noncontrolling Interest and Stockholders Equity/ Members (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Series A Redeemable Convertible Preferred Shares
Stock issuance costs			$ 22
Series B Redeemable Convertible Preferred Shares
Stock issuance costs		$ 243
Common Stock [Member]
Stock issuance costs	$ 10,864	$ 16,995

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities
Net loss	$ (142,181)	$ (72,754)	$ (43,843)
Adjustments to reconcile net loss to net cash used in operating activities:
Acquired in-process research and development assets	0	8,000	0
Share-based compensation expense	27,242	13,321	526
Depreciation expense	63	20	16
Accretion of discounts on short-term investments, net	(2,030)	0	0
Amortization of operating right-of-use assets	468	179	139
Non-cash interest expense	0	0	30
Changes in derivative tranche liabilities	0	0	30,000
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(546)	(3,717)	(1,336)
Deposits and other long-term assets	(300)	(62)	(107)
Accounts payable	(1,484)	1,542	132
Accrued expenses and other current liabilities	9,241	5,114	1,127
Operating lease liabilities	(347)	(182)	(173)
Net cash used in operating activities	(109,874)	(48,539)	(13,489)
Cash flows from investing activities
Cash paid for purchase of short-term investments	(394,206)	0	0
Cash paid for purchase of property and equipment	(26)	0	(92)
Proceeds from maturity of short-term investment	139,158	0	0
Cash paid for acquired in-process research and development assets	0	(8,000)	0
Net cash used in investing activities	(255,074)	(8,000)	(92)
Cash flows from financing activities
Proceeds from issuance of common stock, net	161,610	167,045	0
Proceeds from issuance of common stock upon stock option exercises	3,649		0
Proceeds from issuance of common stock upon ESPP purchase	642	318	0
Net cash provided by financing activities	165,901	297,120	29,977
Net (decrease) increase in cash and cash equivalents	(199,047)	240,581	16,396
Cash and cash equivalents, beginning of period	284,309	43,728	27,332
Cash and cash equivalents, end of period	85,262	284,309	43,728
Supplemental disclosures of noncash activities
Lease liability obtained in exchange for right-of-use asset	940	0	545
Transfers to redeemable convertible noncontrolling interest	0	0	3,551
Exchange of 45,331,483 preferred, common, and incentive shares in connection with the Conversion (Note 1)	0	224,892	0
Exchange of redeemable convertible noncontrolling interest to 6,470,382 shares of common stock (Note 11)	0	3,592	0
Series A Preferred Stock [Member]
Cash flows from financing activities
Proceeds from issuance of redeemable convertible preferred shares, net of issuance costs	0		29,977
Series B Preferred Stock [Member]
Cash flows from financing activities
Proceeds from issuance of redeemable convertible preferred shares, net of issuance costs		$ 129,757	$ 0

Description of Business, Organi

Description of Business, Organization and Liquidity	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business, Organization and Liquidity	1. Description of Business and Organization Organization and Business Day One Biopharmaceuticals, Inc., or the Company, is a clinical-stage biopharmaceutical company dedicated to developing and commercializing targeted therapies for patients of all ages with life-threatening diseases. The Company was formed as a limited liability company under the laws of the State of Delaware in November 2018, under the name Hero Therapeutics Holding Company, LLC. Subsequently, the Company changed its name to Day One Therapeutics Holding Company, LLC in December 2018 and to Day One Biopharmaceuticals Holding Company, LLC, or Day One Holding LLC, in March 2020. On May 26, 2021, the Company completed a conversion by filing a certificate of conversion with the Secretary of State of the State of Delaware and changed its name to Day One Biopharmaceuticals, Inc. Prior to December 31, 2021, the Company had two subsidiaries: DOT Therapeutics-2, Inc. (formerly Hero Therapeutics Inc. and Day One Biopharmaceuticals, Inc.), or DOT-2, incorporated in Delaware in November 2018, and DOT Therapeutics-1, Inc., or DOT-1, incorporated in Delaware in December 2019. DOT-2 and DOT-1 are collectively referred to herein as the Subsidiaries. In December 2021, the Company’s board of directors approved the merger, or the Merger, of the Subsidiaries with and into the Company, with the Company being the surviving corporation, effective December 31, 2021. For more information on the financial statement impact of the Merger, refer to the section titled “Basis of Presentation.” Initial Public Offering, Corporate Conversion and Exchange of Takeda’s shares On June 1, 2021, the Company closed its initial public offering, or the IPO, in which it sold an aggregate of 11,500,000 shares of common stock at a price to the public of $ 16.00 per share, which included 1,500,000 shares issued upon the full exercise by the underwriters of their option to purchase additional shares of common stock. The Company received aggregate net proceeds from the IPO of $ 167.0 million, after deducting underwriting discounts and commissions and offering costs, of $ 17.0 million. The common stock began trading on the Nasdaq Global Select Market on May 27, 2021 under the symbol “DAWN.” In contemplation of the IPO, on May 26, 2021, the Company completed a legal entity conversion, or the Conversion, which included the following: Day One Holding LLC (i) converted from a Delaware limited liability company to a Delaware corporation by filing a certificate of conversion with the Secretary of State of the State of Delaware and (ii) changed its name to Day One Biopharmaceuticals, Inc. As part of the Conversion: • holders of Series A redeemable convertible preferred shares of Day One Holding LLC received one share of Series A redeemable convertible preferred stock of the Company for each Series A redeemable convertible preferred share held immediately prior to the Conversion; • holders of Series B redeemable convertible preferred shares of Day One Holding LLC received one share of Series B redeemable convertible preferred stock of the Company for each Series B redeemable convertible preferred share held immediately prior to the Conversion; • holders of common shares of Day One Holding LLC received one share of common stock of the Company for each common share held immediately prior to the Conversion; • each outstanding incentive share in Day One Holding LLC converted into a number of shares of common stock of the Company based upon a conversion price determined by the board of directors. The conversion price was determined as a difference between the IPO price of $ 16.00 per share and the participating threshold for each incentive share. The Company issued 5,433,290 common stock shares upon the conversion of incentive shares of Day One Holding LLC, of which 4,719,605 common stock shares continue to vest as per the original vesting terms of the incentive shares awards. In connection with the IPO and the Conversion, pursuant to the terms of the Millennium Stock Exchange Agreement, or the Millennium Stock Exchange Agreement, and the Conversion, Millennium Pharmaceuticals, Inc. exchanged 9,857,143 shares of Series A redeemable convertible preferred stock of DOT-1, a subsidiary of Day One Holding LLC, for 6,470,382 shares of common stock of the Company, or the Exchange. The Company holds all property and assets of Day One Holding LLC and assumed all of the debts and obligations of Day One Holding LLC. Effective on the date of the Conversion, each member of the board of directors and each officer of Day One Holding LLC became a member of the board of directors and an officer of the Company. The Conversion was a tax-free reorganization, that included authorization to issue capital stock consisting of 500,000,000 shares of common stock, $ 0.0001 par value per share, and 10,000,000 shares of undesignated preferred stock, $ 0.0001 par value per share. Upon the closing of the IPO, 32,489,398 shares of redeemable convertible preferred stock issued by the Company in the Conversion converted into an equal number of shares of common stock. The Company also granted options for 4,418,874 shares of common stock at an exercise price of $ 16.00 per share upon the IPO date. Shares Split On May 23, 2021, the board of directors of Day One Holding LLC approved an amendment to its operating agreement to effect a forward split of the Company’s shares at a 2.325-for-1 ratio, or the Stock Split. The Stock Split became effective on May 23, 2021, upon approval by the members and execution of the amended LLC operating agreement. All issued and outstanding common shares, redeemable convertible preferred shares, incentive shares and per share amounts contained in these consolidated financial statements have been retroactively adjusted to reflect this Stock Split for all periods presented. Risks and Uncertainties Related to COVID-19 The full impact of the ongoing COVID-19 pandemic remains highly uncertain and subject to change. There are many uncertainties around the COVID-19 pandemic and future developments, which are unpredictable, may result in a material, negative impact to the Company's operations and financial condition. The Company has experienced and expect to continue to experience volatility in services rendered from its third-party service providers as local governments respond to resurgences and the emergence of new strains, each of which may result in the prolonged reinstitution, extension or enhancement of protective measures. With respect to manufacturing and supply, the Company does not anticipate disruptions to its drug supply chain, and it cannot be sure if lock-down measures or restrictions will be implemented and what, if any, impact that may have on its facilities and operations. The Company's management team continues to actively monitor this evolving health crisis and its effects on its operations, key vendors and workforce.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policie s Basis of Presentation The accompanying consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America, or U.S. GAAP, and include the accounts of the Company’s subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Because the Merger (refer to the section “Organization and Business”) did not constitute a change in the reporting entity, as defined in Accounting Standard Codification, or ASC, 250, Accounting changes and error corrections , the Company has reported the assets and liabilities transferred from its Subsidiaries at historical carrying value, prospectively from December 31, 2021. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in ASC and Accounting Standards Updates, or ASU, of the Financial Accounting Standards Board, or FASB. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include, but are not limited to, the valuation of share-based awards, the valuation of deferred tax assets and income tax uncertainties, and accruals for research and development activities. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable. Actual results may differ from those estimates or assumptions. Segments The Company has determined that its chief executive officer is the chief operating decision maker, or CODM. The Company operates and manages the business as one reporting and one operating segment, which is the business of identifying and advancing targeted therapies for patients of all ages with genomically defined cancers. The Company’s CODM reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance. All of the Company’s assets are located in the United States. Concentration of credit risk and other risks and uncertainties Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. The Company’s cash, cash equivalents and short-term investments are held in more than one financial institution in the United States. Amounts on deposit may at times exceed federally insured limits. Management believes that the financial institutions that the Company's cash, cash equivalents and short-term investments are held at are financially sound and, accordingly, minimal credit risk exists with respect to the financial institutions. The Company is subject to certain risks and uncertainties and believes that changes in any of the following areas could have a material adverse effect on the Company's future financial position or results of its operations: ability to obtain future financing; regulatory requirements for approval and market acceptance of, and reimbursement for, product candidates; performance of third-party clinical research organizations and manufacturers upon which the Company relies; development of sales channels; protection of the Company’s intellectual property; litigation or claims against the Company based on intellectual property, patent, product, regulatory or other factors; changes to the market landscape; and the Company’s ability to attract and retain employees necessary to support its growth. The Company is dependent on third-party manufacturers to supply products for research and development activities in its programs. 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 these programs. These programs could be adversely affected by a significant interruption in the supply of active pharmaceutical ingredients and formulated drugs. Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less at the time of purchase to be cash equivalents. The Company’s cash equivalents consist of investments in money market funds and U.S. government agency securities. Cash equivalents are recognized at amortized cost, which approximates fair value. Investments The Company’s investments are comprised of U.S. government agency securities and U.S. treasury securities. Investments are classified at the time of purchase, based on management’s intent, as held-to-maturity, available-for-sale, or trading. All of the Company’s investments are classified as available-for-sale. Available-for-sale securities are carried at estimated fair value with unrealized holdings gains and losses (net of tax effects) on such investments reported in other comprehensive (loss) income as a separate component on the consolidated statements of comprehensive loss. Fair value is determined based on quoted market rates when observable or by utilizing data points that are observable, such as quoted prices, interest rates, and yield curves. For available-for-sale securities, the Company determines if any impairment is related to credit loss or non-credit loss. In making the assessment of whether a loss is from credit or other factors, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows is less than the amortized cost basis, a credit loss exists and an allowance is created, limited by the amount that the fair value is less than amortized cost basis. Subsequent activity related to the credit loss component in the form of write-offs or recoveries is recognized as part of the allowance for credit losses on available-for-sale securities. Fair Value of Financial Instruments Assets and liabilities recorded at fair value on a recurring basis in the consolidated balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability 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. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The carrying amounts reflected in the accompanying consolidated balance sheets for cash equivalents, prepaid expenses, other current assets, accounts payable, accrued expenses and other current liabilities approximate their fair values, due to their short-term nature. Property and Equipment, Net Property and equipment are recorded at cost, less accumulated depreciation and amortization. Depreciation is recognized using the straight-line method over the estimated useful lives of the related assets ranging from three to five years, and leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset. Leases Contractual arrangements that meet the definition of a lease are classified as operating or finance leases and are recorded on the consolidated balance sheets as both a right-of-use asset, or ROU asset, and lease liability, calculated by discounting fixed lease payments over the lease term at the rate implicit in the lease or the Company’s incremental borrowing rate, or IBR. Lease ROU assets and lease obligations are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. The Company currently does not have any finance leases. Operating lease ROU assets are adjusted for (i) payments made at or before the commencement date, (ii) initial direct costs incurred, and (iii) tenant incentives under the lease. As the implicit rate for the operating leases are not determinable, the Company determines its IBR based on the information available at the applicable lease commencement date. The IBR is determined by using the rate of interest that the Company would pay to borrow on a collateralized basis an amount equal to the lease payments for a similar term and in a similar economic environment where the asset is located. The Company considers a lease term to be the noncancelable period that it has the right to use the underlying asset, including any periods where it is reasonably certain the Company will exercise any option to extend the contract. Lease costs for minimum lease payments for operating leases are recognized on a straight-line basis over the lease term. Lease liabilities are increased by interest and reduced by payments each period, and the ROU asset is amortized over the lease term. Variable lease costs are recorded when incurred. In measuring the ROU assets and lease liabilities, the Company has elected to combine lease and non-lease components. The Company excludes short-term leases, if any, having initial terms of 12 months or less at lease commencement as an accounting policy election, and recognizes rent expense on a straight-line basis over the lease term for these types of leases. Impairment of Long-Lived Assets The Company evaluates long-lived assets, which consist of property and equipment and right-of-use assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. To date, no impairments have been recognized in the consolidated financial statements. Research and Development Expenses Research and development expenses consist of costs associated with acquiring technology and intellectual property licenses that have no alternative future uses; costs incurred under agreements with third-party contract research organizations, contract manufacturing organizations and other third parties that conduct clinical trials on the Company’s behalf; other costs associated with research and development programs, including laboratory materials and supplies; employee-related costs, including salaries, benefits and share-based compensation expense, for the Company’s research and development personnel; and facilities and other overhead expenses, including expenses for rent and facilities maintenance, and amortization. The Company’s expense research and development costs as incurred. The Company is obligated to make upfront payments upon execution of certain research and development agreements. Advance payments, including nonrefundable amounts, for goods or services that will be used or rendered for future research and development activities are deferred. Such amounts are recognized as expense as the related goods are delivered or the related services are performed, or such time when the Company does not expect the goods to be delivered or services to be performed. Accrued Research and Development Expenses The Company records accrued liabilities for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical and clinical studies, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued liabilities in the balance sheets and within research and development expenses in the consolidated statements of operations. These costs are a significant component of our research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with third-party service providers under the service agreements. The Company makes judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. The Company makes payments in connection with clinical trials under contracts with contract manufacturing organizations and contract research organizations that support conducting and managing clinical trials. The financial terms of these contracts are subject to negotiation, which vary by contract and may result in payments that do not match the periods over which materials or services are provided. Generally, these agreements set forth the scope of work to be performed at a fixed fee, unit price or on a time and materials basis. In the event the Company makes advance payments for goods or services that will be used or rendered for future research and development activities, the payments are deferred and capitalized as a prepaid expense and recognized as expense as the goods are received or the related services are rendered. Such payments are evaluated for current or long-term classification based on when they are expected to be realized. Patent Costs All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty of the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses in the consolidated statements of operations. Redeemable Convertible Preferred Shares The Company recorded redeemable convertible preferred shares at their respective fair values on the dates of issuance, net of issuance costs. The redeemable convertible preferred shares were recorded outside of members’ deficit because while they were not mandatorily redeemable, in the event of a deemed liquidation event, which was outside of the Company’s control, the proceeds were distributed first to the redeemable convertible preferred shareholders in accordance with their liquidation preferences. The Company had not adjusted the carrying values of the redeemable convertible preferred shares to their liquidation preferences because it is uncertain whether or when a deemed liquidation event would occur that would obligate it to pay the liquidation preferences to holders of redeemable convertible preferred shares. Redeemable convertible preferred shares were all converted to common stock shares upon the closing of the IPO in May 2021. Redeemable Noncontrolling Interest Redeemable noncontrolling interest represented the portion of equity (net assets) in DOT-1 that was neither directly nor indirectly attributable to the Company. Redeemable noncontrolling interest is classified as temporary equity because preferred shares issued to a holder contained certain redemption features that were not solely within the control of the Company. Share-Based Compensation Prior to the IPO, the Company recognized share-based compensation expense based on the estimated fair value of all share-based awards, incentive shares and restricted share awards, on the date of grant using the option-pricing model. The option-pricing model requires the input of subjective assumptions, including the fair value of the underlying common shares, the expected term of the award, the expected volatility, risk-free interest rates, and the dividend yield. In determining the fair value of common shares, the methodologies used to estimate the enterprise value were performed using methodologies, approaches, and assumptions consistent with the American Institute of Certified Public Accountants Accounting and Valuation Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation . The participation threshold amounts were determined by the board of directors, at the time of grant. The expected life of the awards granted during the period was determined based on an expected time to the liquidation event. The Company applied the risk-free interest rate based on the U.S. Treasury yield in effect at the time of the grant consistent with the life of the award. The expected volatility was based on a peer group in the industry in which the Company did business consistent with the expected time to liquidity. The dividend yield was set at zero as the underlying security did not and was not expected to pay a dividend. Subsequent to closing of the IPO, the Company uses the Black-Scholes valuation model to estimate the fair value of options granted to employees and non-employees, intrinsic value to estimate the fair value of restricted stock award, and fair value of the Company’s common stock at the grant date for restricted stock units. The Black-Scholes option-pricing model, used to estimate fair value of stock options awards, requires the use of the following assumptions: • Fair Value of Common Stock —The Company’s closing price on the Nasdaq market at the grant date. • Expected Term —The expected term represents the period that the share-based awards are expected to be outstanding. The expected term for stock options is calculated using the simplified method, as the weighted-average vesting term of the award and the award’s contract period. The Company utilizes this method due to lack of historical exercise data and the plain-vanilla nature of the Company’s service condition share-based awards. For the Company's performance condition stock option awards, the Company calculated the expected term by taking into consideration the options' contractual life, the timing of when milestones are expected to be achieved, and the expected exercise period by a holder from the vesting date until the contractual term. • Expected Volatility —Since the Company does not have sufficient trading history for its common stock, the expected volatility is estimated based on the average historical volatilities of common stock of comparable publicly traded biopharmaceutical companies over a period equal to the expected term of the stock option grants. The comparable biopharmaceutical companies are chosen based on their size, stage in the life cycle or area of specialty. The Company will continue to apply this process until sufficient historical information regarding the volatility of the common stock price becomes available. • Risk-Free Interest Rate —The risk-free interest rate is based on the U.S. Treasury yield in effect at the time of grant for zero-coupon U.S. Treasury notes with maturities approximately equal to the expected term of the awards. • Expected Dividend Yield —The Company has never paid dividends on the common stock and has no plans to pay dividends on its common stock. Therefore, the expected dividend yield use is zero. The Company uses the straight-line attribution method for recognizing share-based compensation expense. The Company recognizes forfeitures by reducing the expense in the same period the forfeitures occur. The Company recognizes share-based compensation expense for awards with performance conditions when it is probable that the condition will be met, and the award will vest. The Company classifies share-based compensation expense in the consolidated statements of operations in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. Income Taxes Prior to the IPO, the Company was a “pass-through” entity under the Internal Revenue Code with two corporate subsidiaries. Prior to the Conversion, the members of the Company, formerly Day One Biopharmaceuticals Holding Company, LLC, were taxed directly on their respective ownership interests and activity in Day One Biopharmaceuticals Holding Company, LLC. The Company’s consolidated corporate subsidiaries accounted for income taxes under the asset and liability method, as discussed below. Upon the closing of the IPO and the Conversion, the Company’s income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax base and net operating loss and tax credit carryforwards. Deferred tax assets and liabilities are determined based upon the difference between the consolidated financial statement carrying amounts and the tax basis of assets and liabilities and are measured using the enacted tax rate expected to apply to taxable income in the years in which the differences are expected to be reversed. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized. The uncertain income tax positions are recognized at the largest amount that is more likely than not to be sustained upon audit by the relevant taxing authority. Changes in recognition or measurement are reflected in the period in which judgment occurs. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of the provision for income taxes. To date, there have been no interest or penalties recorded in relation to unrecognized tax benefits. Net Loss per Share The Company calculates basic and diluted net loss per share in conformity with the two-class method required for participating securities. Under the two-class method, basic net loss per share is computed by dividing the net loss by the weighted average number of common shares outstanding during the period, without consideration of potential dilutive securities. Diluted net loss per share is computed by dividing the net loss, after adjusting it for loss attributable to redeemable noncontrolling interest, in any, by the sum of the weighted average number of common stock shares outstanding during the period plus the dilutive effects of potentially dilutive securities outstanding during the period. Potentially dilutive securities include incentive shares, unvested restricted common shares and redeemable convertible preferred shares, prior to the IPO. Potentially dilutive securities include unvested restricted stock awards, unvested restricted stock units and stock options, after the IPO. For all periods presented, diluted net loss per share is the same as basic net loss per share since the effect of including potential common stock shares is anti-dilutive and incentive shares participation thresholds were not met. Comprehensive Loss Comprehensive loss represents all changes in stockholders' equity except those resulting from and distributions to stockholders. The Company’s unrealized gains and losses on available-for-sale securities represent the only component of other comprehensive loss that are excluded from the reported net loss and that are presented in the consolidated statements of comprehensive loss. Emerging Growth Company Status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. The JOBS Act does not preclude an emerging growth company from adopting a new or revised accounting standard earlier than the time that such standard applies to private companies. The Company expects to use the extended transition period for any other new or revised accounting standards during the period in which it remains an emerging growth company. Recently Adopted Accounting Pronouncements In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, or ASU 2019-12, which eliminates certain exceptions related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. ASU 2019-12 also clarifies and simplifies other aspects of the accounting for income taxes. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020, with early adoption permitted. The Company adopted ASU 2019-12 on January 1, 2022, and this adoption had no material impact on the Company’s financial statements and related disclosures.

Recurring Fair Value Measuremen

Recurring Fair Value Measurements	12 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Recurring Fair Value Measurements The following table sets forth the Company’s financial instruments as of December 31, 2022 and 2021, which are measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): December 31, 2022 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ 18,765 $ — $ — $ 18,765 U.S. treasury securities — 145,785 — 145,785 U.S. government agency securities — 136,022 — 136,022 Total assets measured at fair value $ 18,765 $ 281,807 $ — $ 300,572 December 31, 2021 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ 111,221 $ — $ — $ 111,221 Total assets measured at fair value $ 111,221 $ — $ — $ 111,221 The Company's money market funds are classified as Level 1 because they are measured using observable inputs from active markets for identical assets. The Company's U.S. treasury securities and U.S. government agency securities are classified as Level 2 because they are measured with inputs that are either directly or indirectly observable for the asset which include quoted prices for similar assets in active markets and quoted prices for identical or similar assets in markets that are not active. There were no assets or liabilities classified as Level 3 as of December 31, 2022 and 2021. There were no transfers between Level 1, Level 2 or Level 3 categories during the periods presented. The following tables summarize the estimated fair value of the Company's cash equivalents, available-for-sale securities classified as short-term investments, and associated unrealized gains and losses (in thousands): December 31, 2022 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash equivalents: Money market funds $ 18,765 $ — $ — $ 18,765 U.S. government agency securities 24,800 — — 24,800 Total cash equivalents 43,565 — — 43,565 Short-term investments U.S. treasury securities 145,880 1 ( 96 ) 145,785 U.S. government agency securities 111,197 37 ( 12 ) 111,222 Total short-term investments $ 257,077 $ 38 $ ( 108 ) $ 257,007 December 31, 2021 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash equivalents: Money market funds $ 111,221 $ — $ — $ 111,221 Total cash equivalents $ 111,221 $ — $ — $ 111,221 The following table summarizes the maturities of our cash equivalents and available-for-sale securities as of December 31, 2022 (in thousands): Amortized Cost Fair Value Mature in one year or less $ 300,642 $ 300,572 Total $ 300,642 $ 300,572 The following table presents the breakdown of the Company's available-for-sale securities with gross unrealized losses and the duration that those losses had been unrealized as December 31, 2022 (in thousands): December 31, 2022 Unrealized Losses Less Than 12 Months Unrealized Losses 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Financial assets: U.S. treasury securities $ 140,822 $ ( 96 ) $ — $ — $ 140,822 $ ( 96 ) U.S. government agency securities 26,811 ( 12 ) — — 26,811 ( 12 ) Total financial assets $ 167,633 $ ( 108 ) $ — $ — $ 167,633 $ ( 108 ) The Company did no t have available-for-sale securities with gross unrealized losses as of December 31, 2021. The Company regularly reviews the changes to the rating of its securities and monitors the surrounding economic conditions to assess the risk of expected credit losses. As of December 31, 2022, there were no securities that were in an unrealized loss position for more than 12 months. As of December 31, 2022, the unrealized losses on the Company’s investments in U.S. treasury securities and U.S. government securities were caused by interest rate increases. The current credit ratings are all within the guidelines of the investment policy of the Company and the Company does not expect the issuers to settle any security at a price less than the amortized cost basis of the investment with the contractual cash flows of these investments guaranteed by the issuer. No allowance for credit losses has been recorded since it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost basis.

Balance Sheet Items

Balance Sheet Items	12 Months Ended
	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Items	4. Balance Sheet Items Prepaid Expenses and Other Current Assets Prepaid and other current assets consisted of the following (in thousands): December 31, December 31, Prepaid research and development expenses $ 3,007 $ 2,099 Prepaid insurance 1,592 1,945 Other prepaid expenses and other assets 1,006 1,015 Total prepaid expenses and other current assets $ 5,605 $ 5,059 Property and Equipment, Net Property and equipment, net, consisted of the following (in thousands): December 31, December 31, Leasehold improvements $ 26 $ 15 Furniture and fixtures — 78 Property and equipment, gross 26 93 Less: accumulated depreciation ( 6 ) ( 36 ) Property and equipment, net $ 20 $ 57 Depreciation expense for the years ended December 31, 2022, 2021, and 2020 was approximately $ 63,000 , $ 20,000 , and $ 16,000 , respectively. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, December 31, Accrued research and development expenses $ 7,554 $ 3,308 Accrued payroll related expenses 6,129 2,565 Accrued professional service expenses 2,088 732 Other 179 104 Total accrued expenses and other current liabilities $ 15,950 $ 6,709

Significant Agreements

Significant Agreements	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Significant Agreements	5. Significant Agreements License agreement with Merck KGaA, Darmstadt, Germany On February 10, 2021, DOT-2, the Company’s subsidiary, entered into a license agreement, or the MRKDG License Agreement, with Merck KGaA, Darmstadt, Germany, a pharmaceutical corporation located in Darmstadt, Germany. Under the MRKDG License Agreement, Merck KGaA, Darmstadt, Germany granted to the Company an exclusive worldwide license, with the right to grant sublicenses through multiple tiers, under specified patent rights and know-how for the Company to research, develop, manufacture and commercialize products containing and comprising the pimasertib and MSC2015103B compounds. The Company also received clinical inventory supplies to use in its research and development activities. The Company’s exclusive license grant is subject to a non-exclusive license granted by Merck KGaA, Darmstadt, Germany’s affiliate to a cancer research organization and Merck KGaA, Darmstadt, Germany retains the right to conduct, directly or indirectly, certain ongoing clinical studies relating to pimasertib. Under the MRKDG License Agreement, the Company has obligations to use commercially reasonable efforts to develop and commercialize at least two licensed products in at least two specified major market countries by the year 2029. In consideration for the rights granted under the MRKDG License Agreement and clinical supplies, the Company made an upfront payment of $ 8.0 million, which was recorded as research and development expenses, as the technology does not have an alternative future use and supplies are used for research activities. Additionally, the Company made a milestone payment of $ 2.5 million, which was recorded as research and development expenses due to the nature of the license agreement and the milestone event relating to the first dosing of a patient in a first clinical trial of a product containing pimasertib, in the year ended December 31, 2022. The Company may also be required to make additional payments of up to $ 364.5 million based upon the achievement of specified development, regulatory, and commercial milestones, as well a high, single-digit royalty percentage on future net sales of licensed products, if any. Milestones and royalties are contingent upon future events and will be recorded when the milestones are achieved and when payments are due. The term of the MRKDG License Agreement will expire on a licensed product-by-licensed product and country-by-country basis upon the expiration of the Company’s obligation to pay royalties to the licensor with respect to such licensed product in such country and will expire in its entirety upon the expiration of all of the Company’s payment obligations with respect to all licensed products and all countries under the MRKDG License Agreement. Effective December 31, 2021, DOT-2 was merged with and into the Company, with the Company being the surviving corporation and assuming DOT-2’s obligations under the MRKDG License Agreement. Takeda Asset Purchase Agreement On December 16, 2019, DOT-1, the Company’s subsidiary, entered into an asset purchase agreement, or the Takeda Asset Agreement, with Millennium Pharmaceuticals, Inc., a related party and an affiliate of Takeda Pharmaceutical Company Limited, or Takeda. Pursuant to the Takeda Asset Agreement, DOT-1 purchased certain technology rights and know-how related to TAK-580 (which is now tovorafenib (DAY101)) that provides a new approach for treating patients with primary brain tumors or brain metastases of solid tumors. DOT-1 also received clinical inventory supplies to use in the Company’s research and development activities of such RAF-inhibitor and an assigned investigator clinical trial agreement. Takeda also assigned to DOT-1 its exclusive license agreement, or the Viracta License Agreement, with Viracta Therapeutics, Inc. (f/k/a Sunesis Pharmaceuticals, Inc.), or Viracta. Takeda also granted DOT-1 a worldwide, sublicensable exclusive license under specified patents and know-how and non-exclusive license under other patents and know-how generated by Takeda under the Takeda Asset Agreement. The Company also granted Takeda a grant back license, as defined in the Takeda Asset Agreement, which is terminable either automatically or by DOT-1 in the event Takeda does not achieve specified development milestones within the applicable timeframes set forth under the Takeda Asset Agreement. This grant back license to Takeda was terminated at the time of Conversion in connection with the Millennium Stock Exchange Agreement. In consideration for the sale and assignment of assets and the grant of the license under the Takeda Asset Agreement, DOT-1 made an upfront payment of $ 1.0 million in cash and issued 9,857,143 shares of Series A redeemable convertible preferred stock in DOT-1 in December 2019. The fair value of issued shares was estimated as $ 9.9 million, based on the price paid by other investors for issued shares in the Series A financing of DOT-1. Based on the terms of the Millennium Stock Exchange Agreement, Takeda exchanged the 9,857,143 shares of Series A redeemable convertible preferred stock of DOT-1 for 6,470,382 shares of the Company’s common stock upon the effectiveness of the Conversion, on May 26, 2021. The term of the Takeda Asset Agreement will expire on a country-by-country basis upon expiration of all assigned patent rights and all licensed patent rights in such country. Takeda may terminate the Takeda Asset Agreement prior to the Company's first commercial sale of a product if we cease conducting any development activities for a continuous and specified period of time and such cessation is not agreed upon by the parties and is not done in response to guidance from a regulatory authority. Additionally, Takeda can terminate the Takeda Asset Agreement in the event of the Company's bankruptcy. In the event of termination of the Takeda Asset Agreement by Takeda as a result of our cessation of development or bankruptcy, all assigned patents, know-how and contracts (other than the Viracta License Agreement) will be assigned back to Takeda and Takeda will obtain a reversion license under patents and know-how generated to exploit all such terminated products. Effective December 31, 2021, DOT-1 was merged with and into the Company, with the Company being the surviving corporation and assuming DOT-1’s obligations under the Takeda Assets Purchase Agreement. Viracta License Agreement On December 16, 2019, DOT-1 amended and restated the Viracta License Agreement that was assigned pursuant to the Takeda Asset Agreement. Under the Viracta License Agreement, DOT-1 received a worldwide exclusive license under specified patent rights and know-how to develop, use, manufacture, and commercialize products containing compounds binding the RAF protein family. DOT-1 paid $ 2.0 million upfront in cash to Viracta, which was recorded as research and development expenses in 2019. DOT-1 made a milestone payment of $ 3.0 million to Viracta in February 2021, which was recorded as research and development expense when the milestone was achieved in April 2021. DOT-1 is also required to make additional milestone payments of up to $ 54.0 million upon achievement of specified development and regulatory milestones for each licensed product in two indications, with milestones payable for the second indication to achieve a specified milestone event being lower than milestones payable for the first indication. Additionally, if DOT-1 obtains a priority review voucher with respect to a licensed product and sells such priority review voucher to a third party or uses such priority review voucher, DOT-1 is obligated to pay Viracta a specified percentage in the mid-teen digits of all net consideration received from any such sale or of the value of such used priority review voucher, as applicable. Commencing on the first commercial sale of a licensed product in a country, DOT-1 is obligated to pay tiered royalties ranging in the mid-single-digit percentages on net sales of licensed products, if any. The obligation to pay royalties will end on a country-by-country and licensed product-by-licensed product basis commencing on the first commercial sale in a country and continuing until the later of: (i) the expiration of the last valid claim of the Viracta licensed patents, jointly owned collaboration patents or specified patents owned by the Company covering the use or sale of such product in such country, (ii) the expiration of the last statutory exclusivity pertaining to such product in such country or (iii) the tenth anniversary of the first commercial sale of such product in such country. No other milestones, except as discussed above, were achieved and due as of December 31, 2022. The term of the Viracta License Agreement will expire on a licensed product-by-licensed product and country-by-country basis upon the expiration of the Company’s obligation to pay royalties to Viracta with respect to such product in such country. DOT-1 has the right to terminate the Viracta License Agreement with respect to any or all of the licensed products at will upon a specified notice period. Effective December 31, 2021, DOT-1 was merged with and into the Company, with the Company being the surviving corporation and assuming DOT-1’s obligations under Viracta License Agreement.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies Leases The Company entered into a lease agreement for its corporate office facility in South San Francisco, California in March 2020. Such agreement was determined to be a lease, since the right to control the use of the identified asset was conveyed to the Company for a period of time in exchange for consideration. The Company can extend the lease term for an additional three years at market rates upon the notice of extension. The Company is obligated to pay monthly rent expense and its pro rata share of utilities, common area maintenance expenses, and property taxes. The landlord also provided an allowance of $ 10,000 for tenant improvements. The Company concluded that it is an operating lease. Common area expenses are a non-lease component and a variable consideration and included in operating expenses as incurred. The extension period has not been included in the determination of the Right of Use, or ROU, asset or the lease liability for operating leases as the Company concluded that it is not reasonably certain that it would exercise this option. In October 2022, the Company terminated this lease agreement prior to its scheduled expiration in January 2023. In April 2022, the Company entered into a lease agreement for approximately 12,000 square feet of general use office space in Brisbane, California. Such agreement was determined to be a lease since the right to control the use of the identified asset was conveyed to the Company for a period of time in exchange for consideration. The term of the lease is 31 months and commenced in May 2022. There is no option to extend the lease term nor is there an option to terminate the lease term prior to its expiration. The Company is obligated to pay monthly rent expense and its pro rata share of the landlord's operating expenses which include utilities, common area maintenance expenses, and property taxes. Such expenses are a non-lease component and a variable consideration and included in the Company's operating expenses as incurred. The Company concluded that this lease is also an operating lease. The total payments for base rent over the term of the lease is approximately $ 1.1 million. Upon execution of the agreement, the Company paid a security deposit of approximately $ 40,000 classified as deposits and other long-term assets on the consolidated balance sheet. The Company determined the lease incremental borrowing rate, or IBR, based on the information available at the applicable lease commencement date as the Company’s leases do not provide an implicit rate. The IBR is determined by using the rate of interest that the Company would pay to borrow on a collateralized basis an amount equal to the lease payments for a similar term and in a similar economic environment where the asset is located. As of December 31, 2022, the weighted-average remaining lease term and weighted-average discount rate were 1.9 years and 9.0 %, respectively. The Company’s lease does not require any contingent rental payments, impose financial restrictions, or contain any residual value guarantees. Lease expense of right-of-use assets is recognized on a straight-line basis over the applicable lease term. Lease expense was $ 0.5 million, $ 0.2 million and $ 0.1 million for the years ended December 31, 2022, 2021 and 2020, respectively. Cash paid for amounts included in the measurement of operating lease liabilities was $ 0.4 million, $ 0.2 million and $ 0.2 million for the years ended December 31, 2022, 2021 and 2020, respectively. Variable payments expensed during the years ended December 31, 2022, 2021, and 2020 were immaterial. As of December 31, 2022, the future lease obligations were as follows (in thousands): 2023 $ 458 2024 424 Total future minimum lease payments 882 Less: Imputed interest 69 Present value of operating lease liabilities $ 813 Research and Development Agreements The Company enters into contracts in the normal course of business with clinical research organizations, contract manufacturing organizations, and other third-party vendors for clinical trial, manufacturing, testing, and other research and development activities. These contracts generally provide for termination on notice, with the exception of one vendor where certain costs are non-cancellable after the approval of the project. As of each of December 31, 2022 and 2021, there were no amounts accrued related to termination and cancellation charges as these are not probable. License Agreements The Company entered into the license agreements, as disclosed in Note 5, pursuant to which the Company is required to pay milestones contingent upon meeting of specific events. The first milestone, related to the Viracta License Agreement, was achieved and recorded to research and development expense during the year ended December 31, 2021. The second milestone, related to the MRKDG License Agreement, was achieved and recorded to research and development during the year ended December 31, 2022. The Company may be required to pay royalties on sales of products developed under these agreements. All products are in development as of December 31, 2022 and 2021, and no such royalties were due. Legal Proceedings The Company, from time to time, may be party to litigation arising in the ordinary course of business. The Company is not subject to any material legal proceedings, and to the best of its knowledge, no material legal proceedings are currently pending or threatened. Indemnification Agreements In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for indemnification for certain liabilities. The exposure under these agreements is unknown because it involves claims that may be made against it in the future but have not yet been made. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. However, the Company may record charges in the future as a result of these indemnification obligations. The Company also has indemnification obligations to its directors and executive officers for specified events or occurrences, subject to some limits, while they are serving at its request in such capacities. There have been no claims, to date and the Company believes the fair value of these indemnification agreements is minimal. Accordingly, the Company had no t recorded any liabilities for these agreements as of each of December 31, 2022 and 2021.

Redeemable Convertible Preferre

Redeemable Convertible Preferred Shares	12 Months Ended
	Dec. 31, 2022
Temporary Equity Disclosure [Abstract]
Redeemable Convertible Preferred Shares	7. Redeemable Convertible Preferred Shares On June 1, 2021, the Company completed its IPO, selling an aggregate of 11,500,000 shares of common stock. All outstanding redeemable convertible preferred shares were converted into 32,489,398 shares of common stock upon the completion of the IPO. As of December 31, 2022, the Company did no t have any outstanding shares of redeemable convertible preferred shares. In February 2021, the Company issued 9,638,141 Series B redeemable convertible preferred shares at a price of $ 13.488 per share for gross cash proceeds of $ 130 .0 million. The Company incurred issuance costs of $ 243,000 .

Common Stock

Common Stock	12 Months Ended
	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Common Stock	8. Common Stock Pursuant to its certificate of incorporation, the Company is authorized to issue 500.0 million shares of common stock at a par value of $ 0.0001 per share. As of December 31, 2022, 73,458,176 shares of common stock were issued and outstanding. In November 2018, the Company entered into common shares purchase agreements with two founders of the Company. The individuals purchased a total of 2,790,000 common shares for a total purchase price of $ 300 . Shares vested monthly for two and four years, respectively. Vesting for a certain number of shares was accelerated upon the Company’s closing of its Series A redeemable convertible preferred share financing. The Company also has an option for a period of ninety days after the individual’s employment is terminated either voluntarily or involuntarily to repurchase the unvested common shares at a price that is the lower of the original price per share paid by the founder for such stock or the fair value as of the date of such repurchase. The founders’ shares were converted to common stock in the Conversion. As of December 31, 2022, all founders’ common stock were vested. At-The-Market Offering In June 2022, the Company entered into an equity distribution agreement with Piper Sandler & Co. and JonesTrading Institutional Services LLC, as sales agents, relating to the issuance and sale of shares of the Company’s common stock for an aggregate offering price of up to $ 150.0 million under an at-the-market offering program, or the 2022 ATM. During the year ended December 31, 2022, the Company did not make any sales under the 2022 ATM. June 2022 Follow-On Offering In June 2022, the Company completed a follow-on offering and issued and sold 11,500,000 shares of common stock (including the exercise by the underwriters of their option to purchase an additional 1,500,000 shares of common stock) at a price to the public of $ 15.00 per share for net proceeds of approximately $ 161.6 million, after deducting underwriting discounts, commissions, and offering costs. The Company has reserved shares of common stock for future issuances as follows: December 31, Common stock options issued and outstanding 7,634,167 Common stock available for future grants 1,839,775 Common stock available for ESPP 1,101,756 Restricted stock units issued and outstanding 485,351 Total 11,061,049

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Share-based Compensation	9. Share-Based Compensation Prior to the Conversion, Day One Holding LLC granted incentive shares under the Incentive Share Plan and was authorized to issue 8,924,177 incentive shares. Incentive shares were a separate non-voting class of shares that participated in distributions only after incentive shares vested, unless it was approved by the board of directors and included at least two of the preferred members, and a participation threshold was met. The incentive shares represented profits interests in Day One Holding LLC, which was an interest in the increase in the Company’s value over the participation threshold, as defined in its operating agreement and as determined at the time of grant. A holder of incentive shares had the right to participate in distributions of profits only in excess of the participation threshold. The participation threshold was based on the valuation of the Company’s common shares on or around the grant date. The fair value of the incentive shares was estimated using an option pricing model with the following assumptions: Year Ended December 31, 2021 2020 Common share fair value $ 6.36 - $ 8.89 $ 0.85 - $ 2.10 Participating threshold $ 6.36 - $ 7.51 $ 0.27 Risk free rate 0.14 % 0.16 % - 0.30 % Volatility 72.90 % 78.00 % - 80.00 % Time to liquidity (in years) 0.20 - 1.80 3.03 - 3.33 Grant date fair value $ 4.24 - $ 4.52 $ 0.71 - $ 1.67 During the Conversion, the Company converted all incentive shares to vested and unvested shares of common stock. As such, there was no incentive shares activity for the year ended December 31, 2022. The Company used the option pricing model to estimate the fair value of each incentive shares award on the date of grant. The members’ equity value was based on a recent enterprise valuation analysis performed and common share fair value. The participation threshold amounts were determined by the board of directors at the time of grant. The expected life of the awards granted during the period was determined based on an expected time to the liquidation event. The Company applied the risk-free interest rate based on the U.S. Treasury yield in effect at the time of the grant. Fair Value of Common Share Prior to the IPO, management’s approach to estimate the fair value of the common share was consistent with the methods outlined in the American Institute of Certified Public Accountants’ Practice Aid, Valuation of Privately-Held-Company Equity Securities Issued as Compensation , or the Practice Aid, considering a number of objective and subjective factors including: valuations of common shares performed with the assistance of independent third-party valuation specialists; the Company’s stage of development and business strategy, including the status of research and development efforts, and the material risks related to the business and industry; the Company’s results of operations and financial position, including levels of available capital resources; the valuation of publicly traded companies in the life sciences and biotechnology sectors, as well as recently completed mergers and acquisitions of peer companies; the lack of marketability of the common shares; the prices of redeemable convertible preferred shares sold to investors in arm’s length transactions and the rights, preferences, and privileges of the Company’s redeemable convertible preferred shares relative to those of common shares; the likelihood of achieving a liquidity event for the holders of the common and redeemable convertible preferred shares, such as an initial public offering or a sale, given prevailing market conditions. The fair value of the common shares was approved by the board of directors until such time as the Company shares were listed on an established stock exchange or national market system. The incentive shares were classified as equity awards and share-based compensation expense was based on the grant date fair value of the award. The following table provides a summary of the incentive shares activity: Number of Weighted Average Outstanding as of December 31, 2020 4,112,017 $ 1.26 Granted 2,959,795 $ 4.32 Forfeited ( 265,596 ) $ 1.67 Converted to unvested common stock ( 6,806,216 ) $ 2.58 Outstanding as of December 31, 2021 — $ — 2022 Equity Inducement Plan In October 2022, the board of directors and stockholders approved the 2022 Equity Inducement Plan, or the 2022 Plan. The 2022 Plan provides for the grant of non-statutory stock options and restricted stock units. The number of shares of common stock reserved for issuance under the 2022 Plan is 1,000,000 shares. The following table provides a summary of stock option activity under the 2022 Plan during the year ended December 31, 2022. Options Weighted-Average Weighted-Average Aggregate Outstanding at December 31, 2021 — $ — Granted 309,000 $ 21.14 Exercised — $ — $ — Forfeiture — $ — Outstanding at December 31, 2022 309,000 $ 21.14 9.8 $ 117 Vested and expected to vest at December 31, 2022 309,000 $ 21.14 9.8 $ 117 Exercisable at December 31, 2022 — $ — — $ — Aggregate intrinsic value represents the difference between the estimated fair value of the underlying common stock and the exercise price of outstanding, in-the-money options. There was no fair value of options that vested during the years ended December 31, 2022, 2021 and 2020. The weighted-average grant date fair value of options granted during the year ended December 31, 2022 was $ 15.08 per share. There was no weighted-average grant date fair value of options granted during the years ended December 31, 2021 and 2020. Unamortized share-based compensation for stock options as of December 31, 2022 was $ 4.5 million, which is expected to be recognized over a weighted-average period of 3.8 years. The Company used the Black-Scholes option pricing model to estimate the fair value of stock options awards granted with the following assumptions: Year Ended 2022 Expected term (in years) 6.08 Expected volatility 79.53 % Risk-free interest rate 4.18 % Expected dividend yield — The following table provides a summary of restricted stock units activity under the 2022 Plan during the year ended December 31, 2022: Number of Weighted Average Unvested restricted stock units at December 31, 2021 — $ — Granted 47,400 $ 21.14 Vested — $ — Forfeiture — $ — Unvested restricted stock units at December 31, 2022 47,400 $ 21.14 Unamortized share-based compensation for restricted stock units as of December 31, 2022 was $ 1.0 million, which is expected to be recognized over a weighted-average period of 3.9 years. 2021 Equity Incentive Plan Immediately prior to consummation of the IPO, all the outstanding incentive shares were converted into common stock. The following table provides a summary of the unvested common stock awards activity during the year ended December 31, 2022. Number of Weighted Average Unvested common stock as of December 31, 2021 3,753,862 $ 16.00 Vested ( 1,624,674 ) $ 16.00 Forfeiture ( 406,444 ) $ 16.00 Unvested common stock as of December 31, 2022 1,722,744 $ 16.00 In May 2021, in connection with the IPO, the board of directors and stockholders approved, the 2021 Equity Incentive Plan, or the 2021 Plan, which became effective on the day before the date of the effectiveness of the IPO. The 2021 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, awards of restricted stock, restricted stock units and other share-based awards. The number of shares of common stock reserved for issuance under the 2021 Plan is equal to the sum of: (x) 6,369,000 shares of common stock; plus (y) 4,719,605 shares of common stock issued in respect of the Conversion of incentive shares that were subject to vesting immediately prior to the effectiveness of the registration statement for the IPO that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by us at their original issuance price pursuant to a contractual repurchase right. The number of shares available for grant and issuance under the 2021 Plan will be automatically increased on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2021 and continuing for each fiscal year until, and including, the fiscal year commencing on January 1, 2031, by the lesser of (a) 5 % of the number of shares of all classes of the Company’s common stock, plus the total number of shares of Company common stock issuable upon conversion of any preferred stock or exercise of any warrants to acquire shares of Company common stock for a nominal exercise price issued and outstanding on each December 31 immediately prior to the date of increase or (b) such number of shares determined by the board of directors. The following table provides a summary of stock option activity under the 2021 Plan during the year ended December 31, 2022. Options Weighted-Average Weighted-Average Aggregate Outstanding at December 31, 2021 5,071,896 $ 16.90 Granted 3,284,580 $ 15.45 Exercised ( 235,474 ) $ 15.70 $ 1,604 Forfeiture ( 486,835 ) $ 15.17 Outstanding at December 31, 2022 7,634,167 $ 16.42 8.8 $ 40,759 Vested and expected to vest at December 31, 2022 7,634,167 $ 16.42 8.8 $ 40,759 Exercisable at December 31, 2022 2,287,512 $ 16.46 8.6 $ 12,050 Aggregate intrinsic value represents the difference between the estimated fair value of the underlying common stock and the exercise price of outstanding, in-the-money options. The total fair value of options that vested during the years ended December 31, 2022 and 2021 was $ 23.1 million and $ 1.1 million, respectively. There was no fair value of options that vested during the year ended December 31, 2020. The weighted-average grant date fair value of options granted during the years ended December 31, 2022 and 2021 were $ 9.61 per share and $ 9.91 per share, respectively. There was no weighted-average grant date fair value of options granted during the year ended December 31, 2020. Unamortized share-based compensation for stock options as of December 31, 2022 was $ 49.8 million, which is expected to be recognized over a weighted-average period of 2.7 years. The Company used the Black-Scholes option pricing model to estimate the fair value of stock options awards granted with the following assumptions: Year Ended 2022 2021 Expected term (in years) 5.27 - 6.33 5.31 - 6.08 Expected volatility 65.20 % - 81.68 % 61.25 % - 66.53 % Risk-free interest rate 1.47 % - 4.37 % 0.82 % - 1.39 % Expected dividend yield — — The following table provides a summary of restricted stock units activity under the 2021 Plan during the year ended December 31, 2022: Number of Weighted Average Unvested restricted stock units at December 31, 2021 96,890 $ 22.93 Granted 503,095 $ 15.47 Vested ( 79,441 ) $ 16.82 Forfeiture ( 35,193 ) $ 14.14 Unvested restricted stock units at December 31, 2022 485,351 $ 16.83 Unamortized share-based compensation for restricted stock units as of December 31, 2022 was $ 7.5 million, which is expected to be recognized over a weighted-average period of 3.3 years. Performance Awards In June 2022, the Company granted performance awards, consisting of performance stock options, or PSOs, and performance stock units, or PSUs, to non-executive employees pursuant to the 2021 Equity Incentive Plan. Each performance award is earned through the achievement of a performance-based metric over a defined performance period determined by the compensation committee of the Company's board of directors. The estimated fair value of the equity awards that contain performance conditions is expensed over the term of the award once the Company has determined that it is probable that the performance conditions will be satisfied. During the year ended December 31, 2022, the Company granted 152,550 PSOs with a weighted-average grant date fair value of $ 7.78 per share and 99,250 PSUs with a weighted-average grant date fair value of $ 15.25 per share. The total fair values of PSOs and PSUs granted were $ 1.2 million and $ 1.5 million, respectively. As of December 31, 2022, no PSOs or PSUs had vested since the achievement of the performance-based metrics of the performance awards was not deemed probable. The Company used the Black-Scholes option pricing model to estimate the fair value of the PSO awards granted with the following assumptions: Year Ended 2022 Expected term (in years) 2.92 - 3.42 Expected volatility 72.72 % - 72.98 % Risk-free interest rate 3.37 % Expected dividend yield — 2021 Employee Stock Purchase Plan In May 2021, the board of directors adopted and the stockholders approved the 2021 Employee Stock Purchase Plan, or the ESPP, which became effective on May 26, 2021. A total of 603,000 shares of common stock were initially reserved for issuance under the ESPP. The number of shares of the common stock reserved for issuance under the ESPP will automatically increase on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2021 and continuing for each fiscal year until, and including, the fiscal year commencing on January 1, 2031, by the lesser of: (a) 1 % of the total number of outstanding shares of common stock of the Company (on an as converted basis outstanding on the immediately preceding December 31 (rounded down to the nearest whole share) and (b) an amount determined by the board of directors. 97,413 shares have been issued under the ESPP as of December 31, 2022. The Company recognized $ 0.5 million and $ 0.2 million of compensation expense related to the ESPP plan for the years ended December 31, 2022 and 2021, respectively. The Company did not recognize any compensation expense related to the ESPP plan for the year ended December 31, 2020. The fair value of our common stock to be issued under the ESPP is estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions: Year Ended 2022 2021 Expected term (in years) 0.50 0.25 - 0.50 Expected volatility 128.95 % 42.5 % - 48.4 % Risk-free interest rate 4.54 % 0.05 % - 0.06 % Expected dividend yield — — Share-based compensation expense recorded in the accompanying consolidated statements of operations is as follows (in thousands): Year Ended December 31, 2022 2021 2020 Research and development expense $ 8,486 $ 3,840 $ 212 General and administrative expense 18,756 9,481 314 Total share-based compensation expense $ 27,242 $ 13,321 $ 526 As of December 31, 2022, there was $ 70.1 million of unrecognized compensation cost related to unvested restricted stock, unvested restricted stock units, unvested stock options, and shares subject to purchase under the ESPP that is expected to be recognized over a weighted-average period of approximately 2.8 years. As of December 31, 2022, there was $ 2.6 million of unrecognized compensation cost related to unvested PSOs and PSUs. The Company will recognize the PSO and PSU expense through the expected vesting dates when the achievement of the performance-based metrics is probable.

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Net Loss Per Share	10. Net Loss Per Share Basic and diluted net loss per share attributable to common shareholders/stockholders after the Conversion is calculated as follows (in thousands except share and per share amounts): Twelve Months Ended 2022 2021 2020 Net loss $ ( 142,181 ) $ ( 72,754 ) $ ( 43,843 ) Net loss attributable to redeemable convertible noncontrolling interests — ( 2,109 ) ( 3,336 ) Exchange of redeemable noncontrolling interest shares – deemed dividend — ( 99,994 ) — Net loss attributable to common stockholders/members ( 142,181 ) ( 170,639 ) ( 40,507 ) Net loss per share, basic and diluted $ ( 2.17 ) $ ( 4.62 ) $ ( 7.33 ) Weighted-average number of common shares used in computing net loss per share, basic and diluted 65,466,773 36,960,569 5,529,519 The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: As of December 31, 2022 2021 2020 Stock options 7,943,167 5,071,896 — Unvested common shares 1,722,744 3,753,862 193,766 Restricted stock units 532,751 96,890 — Shares committed under ESPP 44,672 25,362 — Redeemable convertible preferred shares — — 22,851,257 Incentive shares — — 4,112,017 Total 10,243,334 8,948,010 27,157,040

Redeemable Noncontrolling Inter

Redeemable Noncontrolling Interest	12 Months Ended
	Dec. 31, 2022
Temporary Equity Disclosure [Abstract]
Redeemable Noncontrolling Interest	11. Redeemable Noncontrolling Interest Prior to the Merger, DOT-1, the Company’s subsidiary, issued Series A redeemable convertible preferred shares to Takeda in accordance with the Takeda Asset Agreement (Note 5). The Company concluded that it represented a redeemable noncontrolling interest. The Company adjusted the carrying value of redeemable noncontrolling interest to allocate net losses of the subsidiary to Takeda. Transfers to and from the redeemable noncontrolling interest represented changes in ownership and the allocation of Series A redeemable convertible preferred shares issuance costs issued by the subsidiary. On May 26, 2021, pursuant to the terms of the Millennium Stock Exchange Agreement, Takeda exchanged 9,857,143 shares of Series A redeemable convertible preferred stock in DOT-1 for 6,470,382 shares of common stock of the Company. Prior to the Exchange, the Company accounted for the redeemable noncontrolling interest as discussed in the paragraph above and allocated $ 2.1 million of net losses to Takeda for the period from January 1, 2021 to May 26, 2021. The Exchange resulted in DOT-1 becoming a wholly owned subsidiary of the Company and was recorded for accounting purposes as an extinguishment of the redeemable noncontrolling interest. As such, the Company also recognized an extinguishment loss of $ 100.0 million to additional paid-in-capital, which was calculated as a difference between the fair value of common stock issued to Takeda in the conversion and the carrying value of redeemable noncontrolling interest at the conversion date. The all-stock exchange was treated as a deemed dividend in the calculation of net loss attributable to common stockholders/members and net loss per share.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes Prior to the IPO and conversion, the Company was treated as a partnership for tax purposes, and thus, not subject to income taxes. It was the responsibility of the LLC members to report their proportion share of any taxable income or loss generated by Day One Biopharmaceuticals Holdings Company, LLC to the appropriate taxing authorities and pay the associated taxes, if any. Prior to the Conversion, the Company’s consolidated subsidiaries were treated as corporations for tax purposes and were subject to income taxes which have been included in the consolidated financial statements. Subsequent to the Conversion, the Company and its subsidiaries are treated as a consolidated corporate group for tax purposes. On December 31, 2021, the Company liquidated the prior subsidiaries into the Company in a tax-free Internal Revenue Code Section 332 liquidation. As such, a single entity provision and subsequent tax return is calculated for the year ended December 31, 2022. All pre-tax losses have been incurred in the United States. The effective tax rate of the Company’s provision (benefit) for income taxes differs from the federal statutory rate as follows: Year Ended December 31, 2022 2021 2020 Statutory rate 21.0 % 21.0 % 21.0 % State tax 0.6 % ( 0.8 )% 2.3 % Permanent differences — 0.6 % ( 14.4 )% Credits 1.7 % 3.8 % 1.4 % Change in valuation allowance ( 22.6 )% ( 21.5 )% ( 10.1 )% Share-based compensation ( 0.7 )% ( 3.1 )% ( 0.2 )% Total — — — Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The principal components of the Company’s deferred tax assets and liabilities consisted of the following (in thousands): As of December 31, 2022 2021 2020 Deferred tax assets Federal and state net operating loss carryforwards $ 25,884 $ 17,270 $ 7,732 Capitalized R&D Section 174 Expense 14,908 — — Credits 6,653 3,670 731 Intangible asset basis 2,562 2,188 — Share-based compensation 2,133 — — Accrued expenses 1,803 709 235 Total deferred tax assets 53,943 23,837 8,698 Total deferred tax liabilities ( 149 ) ( 59 ) ( 97 ) Less: valuation allowance ( 53,794 ) ( 23,778 ) ( 8,601 ) Net deferred tax assets $ — $ — $ — The Company has incurred net operating losses in each year since inception. The Company has not reflected the benefit of any such net operating loss carryforwards in the consolidated financial statements. Due to its history of losses, and lack of other positive evidence, the Company determined that it is more likely than not that its net deferred tax assets will not be realized, and therefore, the net deferred tax assets are fully offset by a valuation allowance at December 31, 2022 and 2021. The Company increased the valuation allowance by $ 30.0 million, $ 15.2 million and $ 4.4 million for the years ended December 31, 2022, 2021, and 2020, respectively. As of December 31, 2022, the Company had federal net operating loss carryforwards, or NOLs, of $ 117.6 million that do not expire and federal tax credits of $ 8.2 million available to offset tax liabilities that begin to expire in 2038 . The Company also has gross state NOLs of $ 17.6 million and state tax credits of $ 1.2 million which are available to offset state tax liabilities. The state NOLs begin to expire in 2038 and the state tax credits do not expire. The Company has not completed a study to determine whether an ownership change per the provisions of Section 382 of the Internal Revenue Code, as well as similar state provisions, has occurred. Utilization of its net operating loss and income tax credit carryforwards may be subject to a substantial annual limitation due to ownership changes that may have occurred or that could occur in the future. These ownership changes may limit the amount of the net operating loss and income tax credit carryover that can be utilized annually to offset future taxable income. In general, an “ownership change” as defined by Section 382 of the Internal Revenue Code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50 percentage points of the outstanding shares of a company by certain shareholders. In accordance with the Tax Cuts and Jobs Act of 2017, Research and Experimental, or R&E, expenses under Internal Revenue Code Section 174 are required to be capitalized beginning in 2022. R&E expenses are required to be amortized over a period of 5 years for domestic expenses and 15 years for foreign expenses. Uncertain Tax Positions In accordance with authoritative guidance, the impact of an uncertain income tax position on the income tax return must be recognized at the largest amount that is more-likely-than-not to be sustained upon audit by the relevant taxing authority. An uncertain income tax position will not be recognized if it has less than a 50% likelihood of being sustained. The following table reconciles the beginning and ending amount of unrecognized tax benefits (in thousands): Year Ended December 31, 2022 2021 2020 Balance at beginning of year $ 1,141 $ 188 $ 2 Additions based on tax positions related to prior year 726 — — Additions based on tax positions related to current year 916 953 186 Reductions based on tax positions related to prior year ( 248 ) — — Reductions based on tax positions related to current year — — — Balance at end of year $ 2,535 $ 1,141 $ 188 The entire amount of the unrecognized tax benefits would not impact the Company’s effective tax rate if recognized. The Company has elected to include interest and penalties as a component of tax expense. During the years ended December 31, 2022, 2021 and 2020, the Company did no t recognize accrued interest and penalties related to unrecognized tax benefits. The Company does not anticipate that the amount of existing unrecognized tax benefits will significantly increase or decrease during the next 12 months . The Company files income tax returns in the U.S. federal, California and other state tax jurisdictions. The federal and state income tax returns from December 31, 2018 to December 31, 2022 remain subject to examination.

Defined Contribution Plan

Defined Contribution Plan	12 Months Ended
	Dec. 31, 2022
Retirement Benefits [Abstract]
Defined Contribution Plan	13. Defined Contribution Plan The Company maintains an employee savings plan pursuant to Section 401(k) of the Internal Revenue Code. All employees are eligible to participate provided that they meet the requirements of the plan. For the year ended December 31, 2022, the Company made matching contributions of $ 0.8 million. The Company did not make matching contributions in the prior year.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America, or U.S. GAAP, and include the accounts of the Company’s subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Because the Merger (refer to the section “Organization and Business”) did not constitute a change in the reporting entity, as defined in Accounting Standard Codification, or ASC, 250, Accounting changes and error corrections , the Company has reported the assets and liabilities transferred from its Subsidiaries at historical carrying value, prospectively from December 31, 2021. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in ASC and Accounting Standards Updates, or ASU, of the Financial Accounting Standards Board, or FASB.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include, but are not limited to, the valuation of share-based awards, the valuation of deferred tax assets and income tax uncertainties, and accruals for research and development activities. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable. Actual results may differ from those estimates or assumptions.
Segments	Segments The Company has determined that its chief executive officer is the chief operating decision maker, or CODM. The Company operates and manages the business as one reporting and one operating segment, which is the business of identifying and advancing targeted therapies for patients of all ages with genomically defined cancers. The Company’s CODM reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance. All of the Company’s assets are located in the United States.
Concentration of credit risk and other risks and uncertainties	Concentration of credit risk and other risks and uncertainties Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. The Company’s cash, cash equivalents and short-term investments are held in more than one financial institution in the United States. Amounts on deposit may at times exceed federally insured limits. Management believes that the financial institutions that the Company's cash, cash equivalents and short-term investments are held at are financially sound and, accordingly, minimal credit risk exists with respect to the financial institutions. The Company is subject to certain risks and uncertainties and believes that changes in any of the following areas could have a material adverse effect on the Company's future financial position or results of its operations: ability to obtain future financing; regulatory requirements for approval and market acceptance of, and reimbursement for, product candidates; performance of third-party clinical research organizations and manufacturers upon which the Company relies; development of sales channels; protection of the Company’s intellectual property; litigation or claims against the Company based on intellectual property, patent, product, regulatory or other factors; changes to the market landscape; and the Company’s ability to attract and retain employees necessary to support its growth. The Company is dependent on third-party manufacturers to supply products for research and development activities in its programs. 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 these programs. These programs could be adversely affected by a significant interruption in the supply of active pharmaceutical ingredients and formulated drugs.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less at the time of purchase to be cash equivalents. The Company’s cash equivalents consist of investments in money market funds and U.S. government agency securities. Cash equivalents are recognized at amortized cost, which approximates fair value.
Investments	Investments The Company’s investments are comprised of U.S. government agency securities and U.S. treasury securities. Investments are classified at the time of purchase, based on management’s intent, as held-to-maturity, available-for-sale, or trading. All of the Company’s investments are classified as available-for-sale. Available-for-sale securities are carried at estimated fair value with unrealized holdings gains and losses (net of tax effects) on such investments reported in other comprehensive (loss) income as a separate component on the consolidated statements of comprehensive loss. Fair value is determined based on quoted market rates when observable or by utilizing data points that are observable, such as quoted prices, interest rates, and yield curves. For available-for-sale securities, the Company determines if any impairment is related to credit loss or non-credit loss. In making the assessment of whether a loss is from credit or other factors, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows is less than the amortized cost basis, a credit loss exists and an allowance is created, limited by the amount that the fair value is less than amortized cost basis. Subsequent activity related to the credit loss component in the form of write-offs or recoveries is recognized as part of the allowance for credit losses on available-for-sale securities.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Assets and liabilities recorded at fair value on a recurring basis in the consolidated balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability 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. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The carrying amounts reflected in the accompanying consolidated balance sheets for cash equivalents, prepaid expenses, other current assets, accounts payable, accrued expenses and other current liabilities approximate their fair values, due to their short-term nature.
Property and Equipment, Net	Property and Equipment, Net Property and equipment are recorded at cost, less accumulated depreciation and amortization. Depreciation is recognized using the straight-line method over the estimated useful lives of the related assets ranging from three to five years, and leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset.
Leases	Leases Contractual arrangements that meet the definition of a lease are classified as operating or finance leases and are recorded on the consolidated balance sheets as both a right-of-use asset, or ROU asset, and lease liability, calculated by discounting fixed lease payments over the lease term at the rate implicit in the lease or the Company’s incremental borrowing rate, or IBR. Lease ROU assets and lease obligations are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. The Company currently does not have any finance leases. Operating lease ROU assets are adjusted for (i) payments made at or before the commencement date, (ii) initial direct costs incurred, and (iii) tenant incentives under the lease. As the implicit rate for the operating leases are not determinable, the Company determines its IBR based on the information available at the applicable lease commencement date. The IBR is determined by using the rate of interest that the Company would pay to borrow on a collateralized basis an amount equal to the lease payments for a similar term and in a similar economic environment where the asset is located. The Company considers a lease term to be the noncancelable period that it has the right to use the underlying asset, including any periods where it is reasonably certain the Company will exercise any option to extend the contract. Lease costs for minimum lease payments for operating leases are recognized on a straight-line basis over the lease term. Lease liabilities are increased by interest and reduced by payments each period, and the ROU asset is amortized over the lease term. Variable lease costs are recorded when incurred. In measuring the ROU assets and lease liabilities, the Company has elected to combine lease and non-lease components. The Company excludes short-term leases, if any, having initial terms of 12 months or less at lease commencement as an accounting policy election, and recognizes rent expense on a straight-line basis over the lease term for these types of leases.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates long-lived assets, which consist of property and equipment and right-of-use assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. To date, no impairments have been recognized in the consolidated financial statements.
Research and Development Expenses	Research and Development Expenses Research and development expenses consist of costs associated with acquiring technology and intellectual property licenses that have no alternative future uses; costs incurred under agreements with third-party contract research organizations, contract manufacturing organizations and other third parties that conduct clinical trials on the Company’s behalf; other costs associated with research and development programs, including laboratory materials and supplies; employee-related costs, including salaries, benefits and share-based compensation expense, for the Company’s research and development personnel; and facilities and other overhead expenses, including expenses for rent and facilities maintenance, and amortization. The Company’s expense research and development costs as incurred. The Company is obligated to make upfront payments upon execution of certain research and development agreements. Advance payments, including nonrefundable amounts, for goods or services that will be used or rendered for future research and development activities are deferred. Such amounts are recognized as expense as the related goods are delivered or the related services are performed, or such time when the Company does not expect the goods to be delivered or services to be performed.
Accrued Research and Development Expenses	Accrued Research and Development Expenses The Company records accrued liabilities for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical and clinical studies, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued liabilities in the balance sheets and within research and development expenses in the consolidated statements of operations. These costs are a significant component of our research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with third-party service providers under the service agreements. The Company makes judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. The Company makes payments in connection with clinical trials under contracts with contract manufacturing organizations and contract research organizations that support conducting and managing clinical trials. The financial terms of these contracts are subject to negotiation, which vary by contract and may result in payments that do not match the periods over which materials or services are provided. Generally, these agreements set forth the scope of work to be performed at a fixed fee, unit price or on a time and materials basis. In the event the Company makes advance payments for goods or services that will be used or rendered for future research and development activities, the payments are deferred and capitalized as a prepaid expense and recognized as expense as the goods are received or the related services are rendered. Such payments are evaluated for current or long-term classification based on when they are expected to be realized.
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 of the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses in the consolidated statements of operations.
Redeemable Convertible Preferred Shares	Redeemable Convertible Preferred Shares The Company recorded redeemable convertible preferred shares at their respective fair values on the dates of issuance, net of issuance costs. The redeemable convertible preferred shares were recorded outside of members’ deficit because while they were not mandatorily redeemable, in the event of a deemed liquidation event, which was outside of the Company’s control, the proceeds were distributed first to the redeemable convertible preferred shareholders in accordance with their liquidation preferences. The Company had not adjusted the carrying values of the redeemable convertible preferred shares to their liquidation preferences because it is uncertain whether or when a deemed liquidation event would occur that would obligate it to pay the liquidation preferences to holders of redeemable convertible preferred shares. Redeemable convertible preferred shares were all converted to common stock shares upon the closing of the IPO in May 2021.
Redeemable Noncontrolling Interest	Redeemable Noncontrolling Interest Redeemable noncontrolling interest represented the portion of equity (net assets) in DOT-1 that was neither directly nor indirectly attributable to the Company. Redeemable noncontrolling interest is classified as temporary equity because preferred shares issued to a holder contained certain redemption features that were not solely within the control of the Company.
Share-Based Compensation	Share-Based Compensation Prior to the IPO, the Company recognized share-based compensation expense based on the estimated fair value of all share-based awards, incentive shares and restricted share awards, on the date of grant using the option-pricing model. The option-pricing model requires the input of subjective assumptions, including the fair value of the underlying common shares, the expected term of the award, the expected volatility, risk-free interest rates, and the dividend yield. In determining the fair value of common shares, the methodologies used to estimate the enterprise value were performed using methodologies, approaches, and assumptions consistent with the American Institute of Certified Public Accountants Accounting and Valuation Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation . The participation threshold amounts were determined by the board of directors, at the time of grant. The expected life of the awards granted during the period was determined based on an expected time to the liquidation event. The Company applied the risk-free interest rate based on the U.S. Treasury yield in effect at the time of the grant consistent with the life of the award. The expected volatility was based on a peer group in the industry in which the Company did business consistent with the expected time to liquidity. The dividend yield was set at zero as the underlying security did not and was not expected to pay a dividend. Subsequent to closing of the IPO, the Company uses the Black-Scholes valuation model to estimate the fair value of options granted to employees and non-employees, intrinsic value to estimate the fair value of restricted stock award, and fair value of the Company’s common stock at the grant date for restricted stock units. The Black-Scholes option-pricing model, used to estimate fair value of stock options awards, requires the use of the following assumptions: • Fair Value of Common Stock —The Company’s closing price on the Nasdaq market at the grant date. • Expected Term —The expected term represents the period that the share-based awards are expected to be outstanding. The expected term for stock options is calculated using the simplified method, as the weighted-average vesting term of the award and the award’s contract period. The Company utilizes this method due to lack of historical exercise data and the plain-vanilla nature of the Company’s service condition share-based awards. For the Company's performance condition stock option awards, the Company calculated the expected term by taking into consideration the options' contractual life, the timing of when milestones are expected to be achieved, and the expected exercise period by a holder from the vesting date until the contractual term. • Expected Volatility —Since the Company does not have sufficient trading history for its common stock, the expected volatility is estimated based on the average historical volatilities of common stock of comparable publicly traded biopharmaceutical companies over a period equal to the expected term of the stock option grants. The comparable biopharmaceutical companies are chosen based on their size, stage in the life cycle or area of specialty. The Company will continue to apply this process until sufficient historical information regarding the volatility of the common stock price becomes available. • Risk-Free Interest Rate —The risk-free interest rate is based on the U.S. Treasury yield in effect at the time of grant for zero-coupon U.S. Treasury notes with maturities approximately equal to the expected term of the awards. • Expected Dividend Yield —The Company has never paid dividends on the common stock and has no plans to pay dividends on its common stock. Therefore, the expected dividend yield use is zero. The Company uses the straight-line attribution method for recognizing share-based compensation expense. The Company recognizes forfeitures by reducing the expense in the same period the forfeitures occur. The Company recognizes share-based compensation expense for awards with performance conditions when it is probable that the condition will be met, and the award will vest. The Company classifies share-based compensation expense in the consolidated statements of operations in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified.
Income Taxes	Income Taxes Prior to the IPO, the Company was a “pass-through” entity under the Internal Revenue Code with two corporate subsidiaries. Prior to the Conversion, the members of the Company, formerly Day One Biopharmaceuticals Holding Company, LLC, were taxed directly on their respective ownership interests and activity in Day One Biopharmaceuticals Holding Company, LLC. The Company’s consolidated corporate subsidiaries accounted for income taxes under the asset and liability method, as discussed below. Upon the closing of the IPO and the Conversion, the Company’s income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax base and net operating loss and tax credit carryforwards. Deferred tax assets and liabilities are determined based upon the difference between the consolidated financial statement carrying amounts and the tax basis of assets and liabilities and are measured using the enacted tax rate expected to apply to taxable income in the years in which the differences are expected to be reversed. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized. The uncertain income tax positions are recognized at the largest amount that is more likely than not to be sustained upon audit by the relevant taxing authority. Changes in recognition or measurement are reflected in the period in which judgment occurs. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of the provision for income taxes. To date, there have been no interest or penalties recorded in relation to unrecognized tax benefits.
Net Loss per Share	Net Loss per Share The Company calculates basic and diluted net loss per share in conformity with the two-class method required for participating securities. Under the two-class method, basic net loss per share is computed by dividing the net loss by the weighted average number of common shares outstanding during the period, without consideration of potential dilutive securities. Diluted net loss per share is computed by dividing the net loss, after adjusting it for loss attributable to redeemable noncontrolling interest, in any, by the sum of the weighted average number of common stock shares outstanding during the period plus the dilutive effects of potentially dilutive securities outstanding during the period. Potentially dilutive securities include incentive shares, unvested restricted common shares and redeemable convertible preferred shares, prior to the IPO. Potentially dilutive securities include unvested restricted stock awards, unvested restricted stock units and stock options, after the IPO. For all periods presented, diluted net loss per share is the same as basic net loss per share since the effect of including potential common stock shares is anti-dilutive and incentive shares participation thresholds were not met.
Comprehensive Loss	Comprehensive Loss Comprehensive loss represents all changes in stockholders' equity except those resulting from and distributions to stockholders. The Company’s unrealized gains and losses on available-for-sale securities represent the only component of other comprehensive loss that are excluded from the reported net loss and that are presented in the consolidated statements of comprehensive loss.
Emerging Growth Company Status	Emerging Growth Company Status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. The JOBS Act does not preclude an emerging growth company from adopting a new or revised accounting standard earlier than the time that such standard applies to private companies. The Company expects to use the extended transition period for any other new or revised accounting standards during the period in which it remains an emerging growth company.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, or ASU 2019-12, which eliminates certain exceptions related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. ASU 2019-12 also clarifies and simplifies other aspects of the accounting for income taxes. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020, with early adoption permitted. The Company adopted ASU 2019-12 on January 1, 2022, and this adoption had no material impact on the Company’s financial statements and related disclosures.

Recurring Fair Value Measurem_2

Recurring Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table sets forth the Company’s financial instruments as of December 31, 2022 and 2021, which are measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): December 31, 2022 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ 18,765 $ — $ — $ 18,765 U.S. treasury securities — 145,785 — 145,785 U.S. government agency securities — 136,022 — 136,022 Total assets measured at fair value $ 18,765 $ 281,807 $ — $ 300,572 December 31, 2021 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ 111,221 $ — $ — $ 111,221 Total assets measured at fair value $ 111,221 $ — $ — $ 111,221
Schedule of cash equivalents, marketable securities, and unrealized gains and losses	The following tables summarize the estimated fair value of the Company's cash equivalents, available-for-sale securities classified as short-term investments, and associated unrealized gains and losses (in thousands): December 31, 2022 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash equivalents: Money market funds $ 18,765 $ — $ — $ 18,765 U.S. government agency securities 24,800 — — 24,800 Total cash equivalents 43,565 — — 43,565 Short-term investments U.S. treasury securities 145,880 1 ( 96 ) 145,785 U.S. government agency securities 111,197 37 ( 12 ) 111,222 Total short-term investments $ 257,077 $ 38 $ ( 108 ) $ 257,007 December 31, 2021 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash equivalents: Money market funds $ 111,221 $ — $ — $ 111,221 Total cash equivalents $ 111,221 $ — $ — $ 111,221
Schedule of maturities of our available-for-sale marketable securities table text block	The following table summarizes the maturities of our cash equivalents and available-for-sale securities as of December 31, 2022 (in thousands): Amortized Cost Fair Value Mature in one year or less $ 300,642 $ 300,572 Total $ 300,642 $ 300,572
Schedule of available-for-sale marketable securities with gross unrealized losses	The following table presents the breakdown of the Company's available-for-sale securities with gross unrealized losses and the duration that those losses had been unrealized as December 31, 2022 (in thousands): December 31, 2022 Unrealized Losses Less Than 12 Months Unrealized Losses 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Financial assets: U.S. treasury securities $ 140,822 $ ( 96 ) $ — $ — $ 140,822 $ ( 96 ) U.S. government agency securities 26,811 ( 12 ) — — 26,811 ( 12 ) Total financial assets $ 167,633 $ ( 108 ) $ — $ — $ 167,633 $ ( 108 )

Balance Sheet Items (Tables)

Balance Sheet Items (Tables)	12 Months Ended
	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Schedule of Prepaid and Other Current Assets	Prepaid and other current assets consisted of the following (in thousands): December 31, December 31, Prepaid research and development expenses $ 3,007 $ 2,099 Prepaid insurance 1,592 1,945 Other prepaid expenses and other assets 1,006 1,015 Total prepaid expenses and other current assets $ 5,605 $ 5,059
Schedule of Property and Equipment, Net	Property and equipment, net, consisted of the following (in thousands): December 31, December 31, Leasehold improvements $ 26 $ 15 Furniture and fixtures — 78 Property and equipment, gross 26 93 Less: accumulated depreciation ( 6 ) ( 36 ) Property and equipment, net $ 20 $ 57
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, December 31, Accrued research and development expenses $ 7,554 $ 3,308 Accrued payroll related expenses 6,129 2,565 Accrued professional service expenses 2,088 732 Other 179 104 Total accrued expenses and other current liabilities $ 15,950 $ 6,709

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Schedule Of Prepaid Expenses and Other Current Assets	Prepaid and other current assets consisted of the following (in thousands): December 31, December 31, Prepaid research and development expenses $ 3,007 $ 2,099 Prepaid insurance 1,592 1,945 Other prepaid expenses and other assets 1,006 1,015 Total prepaid expenses and other current assets $ 5,605 $ 5,059

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2022
Property, Plant and Equipment, Net [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net, consisted of the following (in thousands): December 31, December 31, Leasehold improvements $ 26 $ 15 Furniture and fixtures — 78 Property and equipment, gross 26 93 Less: accumulated depreciation ( 6 ) ( 36 ) Property and equipment, net $ 20 $ 57

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2022
Disclosure Text Block [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, December 31, Accrued research and development expenses $ 7,554 $ 3,308 Accrued payroll related expenses 6,129 2,565 Accrued professional service expenses 2,088 732 Other 179 104 Total accrued expenses and other current liabilities $ 15,950 $ 6,709

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Summary of Future Lease Obligations	As of December 31, 2022, the future lease obligations were as follows (in thousands): 2023 $ 458 2024 424 Total future minimum lease payments 882 Less: Imputed interest 69 Present value of operating lease liabilities $ 813

Common Stock (Tables)

Common Stock (Tables)	12 Months Ended
	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Schedule of Common Stock Shares Reserved for Future Issuance	The Company has reserved shares of common stock for future issuances as follows: December 31, Common stock options issued and outstanding 7,634,167 Common stock available for future grants 1,839,775 Common stock available for ESPP 1,101,756 Restricted stock units issued and outstanding 485,351 Total 11,061,049

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of Fair Value of The Incentive Shares Estimated Using An Option Pricing Model	The fair value of the incentive shares was estimated using an option pricing model with the following assumptions: Year Ended December 31, 2021 2020 Common share fair value $ 6.36 - $ 8.89 $ 0.85 - $ 2.10 Participating threshold $ 6.36 - $ 7.51 $ 0.27 Risk free rate 0.14 % 0.16 % - 0.30 % Volatility 72.90 % 78.00 % - 80.00 % Time to liquidity (in years) 0.20 - 1.80 3.03 - 3.33 Grant date fair value $ 4.24 - $ 4.52 $ 0.71 - $ 1.67
Summary of The Incentive Shares Activity	The following table provides a summary of the incentive shares activity: Number of Weighted Average Outstanding as of December 31, 2020 4,112,017 $ 1.26 Granted 2,959,795 $ 4.32 Forfeited ( 265,596 ) $ 1.67 Converted to unvested common stock ( 6,806,216 ) $ 2.58 Outstanding as of December 31, 2021 — $ —
Common stock to be issued under the ESPP Table text block	The fair value of our common stock to be issued under the ESPP is estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions: Year Ended 2022 2021 Expected term (in years) 0.50 0.25 - 0.50 Expected volatility 128.95 % 42.5 % - 48.4 % Risk-free interest rate 4.54 % 0.05 % - 0.06 % Expected dividend yield — —
Summary of Share-based Compensation Expense Recorded in The Accompanying Condensed Consolidated Statements of Operations and Comprehensive Loss	Share-based compensation expense recorded in the accompanying consolidated statements of operations is as follows (in thousands): Year Ended December 31, 2022 2021 2020 Research and development expense $ 8,486 $ 3,840 $ 212 General and administrative expense 18,756 9,481 314 Total share-based compensation expense $ 27,242 $ 13,321 $ 526
Performance Stock Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of The Black-Scholes Option Pricing Model to Estimate The Fair Value of Stock Option Granted	The Company used the Black-Scholes option pricing model to estimate the fair value of the PSO awards granted with the following assumptions: Year Ended 2022 Expected term (in years) 2.92 - 3.42 Expected volatility 72.72 % - 72.98 % Risk-free interest rate 3.37 % Expected dividend yield —
2022 Equity Inducement Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of Stock Option Activity	The following table provides a summary of stock option activity under the 2022 Plan during the year ended December 31, 2022. Options Weighted-Average Weighted-Average Aggregate Outstanding at December 31, 2021 — $ — Granted 309,000 $ 21.14 Exercised — $ — $ — Forfeiture — $ — Outstanding at December 31, 2022 309,000 $ 21.14 9.8 $ 117 Vested and expected to vest at December 31, 2022 309,000 $ 21.14 9.8 $ 117 Exercisable at December 31, 2022 — $ — — $ —
Summary of The Black-Scholes Option Pricing Model to Estimate The Fair Value of Stock Option Granted	The Company used the Black-Scholes option pricing model to estimate the fair value of stock options awards granted with the following assumptions: Year Ended 2022 Expected term (in years) 6.08 Expected volatility 79.53 % Risk-free interest rate 4.18 % Expected dividend yield —
Summary of Restricted Stock Units Activity	The following table provides a summary of restricted stock units activity under the 2022 Plan during the year ended December 31, 2022: Number of Weighted Average Unvested restricted stock units at December 31, 2021 — $ — Granted 47,400 $ 21.14 Vested — $ — Forfeiture — $ — Unvested restricted stock units at December 31, 2022 47,400 $ 21.14
2021 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of Stock Option Activity	The following table provides a summary of stock option activity under the 2021 Plan during the year ended December 31, 2022. Options Weighted-Average Weighted-Average Aggregate Outstanding at December 31, 2021 5,071,896 $ 16.90 Granted 3,284,580 $ 15.45 Exercised ( 235,474 ) $ 15.70 $ 1,604 Forfeiture ( 486,835 ) $ 15.17 Outstanding at December 31, 2022 7,634,167 $ 16.42 8.8 $ 40,759 Vested and expected to vest at December 31, 2022 7,634,167 $ 16.42 8.8 $ 40,759 Exercisable at December 31, 2022 2,287,512 $ 16.46 8.6 $ 12,050
Schedule of Nonvested Share Activity	The following table provides a summary of the unvested common stock awards activity during the year ended December 31, 2022. Number of Weighted Average Unvested common stock as of December 31, 2021 3,753,862 $ 16.00 Vested ( 1,624,674 ) $ 16.00 Forfeiture ( 406,444 ) $ 16.00 Unvested common stock as of December 31, 2022 1,722,744 $ 16.00
Summary of Restricted Stock Units Activity	The following table provides a summary of restricted stock units activity under the 2021 Plan during the year ended December 31, 2022: Number of Weighted Average Unvested restricted stock units at December 31, 2021 96,890 $ 22.93 Granted 503,095 $ 15.47 Vested ( 79,441 ) $ 16.82 Forfeiture ( 35,193 ) $ 14.14 Unvested restricted stock units at December 31, 2022 485,351 $ 16.83
Schedule of Performance Stock Options Assumptions	The Company used the Black-Scholes option pricing model to estimate the fair value of stock options awards granted with the following assumptions: Year Ended 2022 2021 Expected term (in years) 5.27 - 6.33 5.31 - 6.08 Expected volatility 65.20 % - 81.68 % 61.25 % - 66.53 % Risk-free interest rate 1.47 % - 4.37 % 0.82 % - 1.39 % Expected dividend yield — —

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Summary of Basic and Diluted Net Loss Per Share Attributable to Common Shareholders/Stockholders	Basic and diluted net loss per share attributable to common shareholders/stockholders after the Conversion is calculated as follows (in thousands except share and per share amounts): Twelve Months Ended 2022 2021 2020 Net loss $ ( 142,181 ) $ ( 72,754 ) $ ( 43,843 ) Net loss attributable to redeemable convertible noncontrolling interests — ( 2,109 ) ( 3,336 ) Exchange of redeemable noncontrolling interest shares – deemed dividend — ( 99,994 ) — Net loss attributable to common stockholders/members ( 142,181 ) ( 170,639 ) ( 40,507 ) Net loss per share, basic and diluted $ ( 2.17 ) $ ( 4.62 ) $ ( 7.33 ) Weighted-average number of common shares used in computing net loss per share, basic and diluted 65,466,773 36,960,569 5,529,519
Summary of Outstanding Potentially Dilutive Securities Have Been Excluded From Calculation of Diluted Net Loss Per Share	The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: As of December 31, 2022 2021 2020 Stock options 7,943,167 5,071,896 — Unvested common shares 1,722,744 3,753,862 193,766 Restricted stock units 532,751 96,890 — Shares committed under ESPP 44,672 25,362 — Redeemable convertible preferred shares — — 22,851,257 Incentive shares — — 4,112,017 Total 10,243,334 8,948,010 27,157,040

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	The effective tax rate of the Company’s provision (benefit) for income taxes differs from the federal statutory rate as follows: Year Ended December 31, 2022 2021 2020 Statutory rate 21.0 % 21.0 % 21.0 % State tax 0.6 % ( 0.8 )% 2.3 % Permanent differences — 0.6 % ( 14.4 )% Credits 1.7 % 3.8 % 1.4 % Change in valuation allowance ( 22.6 )% ( 21.5 )% ( 10.1 )% Share-based compensation ( 0.7 )% ( 3.1 )% ( 0.2 )% Total — — —
Schedule of Deferred Tax Assets and Liabilities	Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The principal components of the Company’s deferred tax assets and liabilities consisted of the following (in thousands): As of December 31, 2022 2021 2020 Deferred tax assets Federal and state net operating loss carryforwards $ 25,884 $ 17,270 $ 7,732 Capitalized R&D Section 174 Expense 14,908 — — Credits 6,653 3,670 731 Intangible asset basis 2,562 2,188 — Share-based compensation 2,133 — — Accrued expenses 1,803 709 235 Total deferred tax assets 53,943 23,837 8,698 Total deferred tax liabilities ( 149 ) ( 59 ) ( 97 ) Less: valuation allowance ( 53,794 ) ( 23,778 ) ( 8,601 ) Net deferred tax assets $ — $ — $ —
Summary of Unrecognized Tax Benefits	The following table reconciles the beginning and ending amount of unrecognized tax benefits (in thousands): Year Ended December 31, 2022 2021 2020 Balance at beginning of year $ 1,141 $ 188 $ 2 Additions based on tax positions related to prior year 726 — — Additions based on tax positions related to current year 916 953 186 Reductions based on tax positions related to prior year ( 248 ) — — Reductions based on tax positions related to current year — — — Balance at end of year $ 2,535 $ 1,141 $ 188

Description of Business, Orga_2

Description of Business, Organization and Liquidity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Jun. 01, 2021	May 23, 2021	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Proceeds from issuance of initial public offering	$ 167,000
Payments of stock issuance costs	$ 17,000
Share-based compensation arrangement by share-based payment award, options, vested, number of shares				4,719,605
Common stock shares authorized				500,000,000	500,000,000
Preferred stock shares authorized				10,000,000
Common stock par or stated value per share				$ 0.0001	$ 0.0001
Preferred stock par or stated value per share				$ 0.0001
Stockholders' equity note, stock split		2.325-for-1
Retained Earnings (Accumulated Deficit)				$ (269,668)	$ (127,487)
Cash and cash equivalents				$ 85,262	$ 284,309
IPO [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Common stock issued in IPO, net of issuance costs of $16,995, shares	11,500,000		11,500,000
Shares issued, price per share	$ 16			$ 16
Number of shares issued upon conversion				5,433,290
Stock issued during period, shares, conversion of units				32,489,398
Share-based compensation arrangement by share-based payment award, options, grants in period, net of forfeitures				4,418,874
Over-Allotment Option [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock issued during period, shares, issued for services	1,500,000
Series A Redeemable Convertible Preferred Stock [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Common stock par or stated value per share				$ 0.0001
Series A Redeemable Convertible Preferred Stock [Member] | Millennium Pharmaceuticals, Inc. [Member] | The Millennium Stock Exchange Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Conversion of stock, shares converted				9,857,143
Convertible preferred stock, shares issued upon conversion				6,470,382

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Class of Stock [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Payments	$ 0

Recurring Fair Value Measurem_3

Recurring Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 85,262	$ 284,309
Amortized cost, Mature in one year or less	300,642
Fair Value, Mature in one year or less	300,572
Amortized Cost, Total	300,642
Fair Value, Total	300,572
Unrealized Losses Less Than 12 Months, Fair value	167,633
Unrealized Losses Less Than 12 Months, Unrealized losses	(108)
Fair Value	(108)
Unrealized losses	167,633
Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	300,572	111,221
Fair Value, Inputs, Level 1 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	18,765	111,221
Fair Value, Inputs, Level 2 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	281,807	0
Fair Value, Inputs, Level 3 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0	0
Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	18,765	111,221
Cash and cash equivalents	18,765	111,221
Cash Equivalents Unrealized Gains	0	0
Cash Equivalents Unrealized Losses	0	0
Money Market Funds [Member] | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	18,765	111,221
Money Market Funds [Member] | Fair Value, Inputs, Level 1 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	18,765	111,221
Money Market Funds [Member] | Fair Value, Inputs, Level 2 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0	0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0	0
US Treasury Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Unrealized Gain	1
Debt Securities, Available-for-Sale, Unrealized Loss	96
Debt Securities, Available-for-Sale	145,785
Debt Securities, Available-for-Sale, Amortized Cost	145,880
US Treasury Securities [Member] | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	145,785
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	145,785
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0
U.S. government agency securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	24,800
Cash and cash equivalents	24,800
Debt Securities, Available-for-Sale, Unrealized Gain	37
Debt Securities, Available-for-Sale, Unrealized Loss	12
Debt Securities, Available-for-Sale	111,222
Cash Equivalents Unrealized Gains	0
Cash Equivalents Unrealized Losses	0
Debt Securities, Available-for-Sale, Amortized Cost	111,197
U.S. government agency securities [Member] | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	136,022
U.S. government agency securities [Member] | Fair Value, Inputs, Level 1 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0
U.S. government agency securities [Member] | Fair Value, Inputs, Level 2 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	136,022
U.S. government agency securities [Member] | Fair Value, Inputs, Level 3 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	0
Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value disclosure	43,565	111,221
Cash and cash equivalents	43,565	111,221
Cash Equivalents Unrealized Gains	0	0
Cash Equivalents Unrealized Losses	0	$ 0
Marketable Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale, Unrealized Gain	38
Debt Securities, Available-for-Sale, Unrealized Loss	108
Debt Securities, Available-for-Sale	257,007
Debt Securities, Available-for-Sale, Amortized Cost	$ 257,077

Recurring Fair Value Measurem_4

Recurring Fair Value Measurements - Schedule of cash equivalent, marketable securities and unrealized gains and losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 85,262	$ 284,309
Marketable Securities [Member]
Cash and Cash Equivalents [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost	257,077
Debt Securities, Available-for-Sale, Unrealized Gain	38
Debt Securities, Available-for-Sale, Unrealized Loss	(108)
Debt Securities, Available-for-Sale	257,007
Cash Equivalents [Member]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	43,565	111,221
Cash Equivalents Unrealized Gains	0	0
Cash Equivalents Unrealized Losses	0	0
Cash and Cash Equivalents, Fair Value Disclosure	43,565	111,221
Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	18,765	111,221
Cash Equivalents Unrealized Gains	0	0
Cash Equivalents Unrealized Losses	0	0
Cash and Cash Equivalents, Fair Value Disclosure	18,765	$ 111,221
U.S. government agency securities [Member]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	24,800
Cash Equivalents Unrealized Gains	0
Cash Equivalents Unrealized Losses	0
Cash and Cash Equivalents, Fair Value Disclosure	24,800
Debt Securities, Available-for-Sale, Amortized Cost	111,197
Debt Securities, Available-for-Sale, Unrealized Gain	37
Debt Securities, Available-for-Sale, Unrealized Loss	(12)
Debt Securities, Available-for-Sale	111,222
US Treasury Securities [Member]
Cash and Cash Equivalents [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost	145,880
Debt Securities, Available-for-Sale, Unrealized Gain	1
Debt Securities, Available-for-Sale, Unrealized Loss	(96)
Debt Securities, Available-for-Sale	$ 145,785

Recurring Fair Value Measurem_5

Recurring Fair Value Measurements - Schedule of maturities of our available-for-sale marketable securities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Amortized cost, Mature in one year or less	$ 300,642
Amortized Cost, Total	300,642
Fair Value, Mature in one year or less	300,572
Fair Value, Total	$ 300,572

Recurring Fair Value Measurem_6

Recurring Fair Value Measurements - Schedule of available -for -sale marketable securities with gross unrealized losses (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Cash and Cash Equivalents [Line Items]
Unrealized Losses Less Than 12 Months, Fair value	$ 167,633
Unrealized Losses Less Than 12 Months, Unrealized losses	(108)
Unrealized losses 12 months or greater fair value	0
Unrealized losses 12 months or greater unrealized losses	0
Unrealized losses	167,633
Fair Value	(108)
US Treasury Securities [Member]
Cash and Cash Equivalents [Line Items]
Unrealized Losses Less Than 12 Months, Fair value	140,822
Unrealized Losses Less Than 12 Months, Unrealized losses	(96)
Unrealized losses 12 months or greater fair value	0
Unrealized losses 12 months or greater unrealized losses	0
Unrealized losses	140,822
Fair Value	(96)
U.S. government agency securities [Member]
Cash and Cash Equivalents [Line Items]
Unrealized Losses Less Than 12 Months, Fair value	26,811
Unrealized Losses Less Than 12 Months, Unrealized losses	(12)
Unrealized losses 12 months or greater fair value	0
Unrealized losses 12 months or greater unrealized losses	0
Unrealized losses	26,811
Fair Value	$ (12)

Recurring Fair Value Measurem_7

Recurring Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	$ 0	$ 0
Available-for-Sale Securities	0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 0

Balance Sheet Items - Schedule

Balance Sheet Items - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid research and development expenses	$ 3,007	$ 2,099
Prepaid insurance	1,592	1,945
Other prepaid expenses and other assets	1,006	1,015
Total prepaid expenses and other current assets	$ 5,605	$ 5,059

Balance Sheet Items - Summary o

Balance Sheet Items - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 26	$ 93
Less: accumulated depreciation and amortization	(6)	(36)
Property and equipment, net	20	57
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	26	15
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 0	$ 78

Balance Sheet Items - Summary_2

Balance Sheet Items - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Accrued research and development expenses	$ 7,554	$ 3,308
Accrued payroll related expenses	6,129	2,565
Accrued professional service expenses	2,088	732
Other	179	104
Total accrued expenses and other current liabilities	$ 15,950	$ 6,709

Balance Sheet Items - Additiona

Balance Sheet Items - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Balance Sheet Items [Lines items]
Depreciation	$ 63,000	$ 20,000	$ 16,000

Significant Agreements - Additi

Significant Agreements - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 16, 2019	Feb. 28, 2021	Dec. 31, 2022	Dec. 31, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Common stock issued in IPO, net of issuance costs of $16,995				$ 167,045
Common Stock [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Stock Issued During Period, Shares, New Issues				11,500,000
Common stock issued in IPO, net of issuance costs of $16,995				$ 1
Takeda Asset Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront of cash payment	$ 1,000
Takeda Asset Agreement [Member] | Common Stock [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Issuance of Series A redeemable convertible preferred shares, shares	6,470,382
Takeda Asset Agreement [Member] | Series A Redeemable Convertible Preferred Stock [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Stock Issued During Period, Shares, New Issues			9,857,143
Common stock issued in IPO, net of issuance costs of $16,995	$ 9,900
Issuance of Series A redeemable convertible preferred shares, shares	9,857,143
Takeda Asset Agreement [Member] | Research and Development Expense [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment			$ 8,000
Merck License Agreement [Member] | Research and Development Expense [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment of Milestones			2,500
Merck License Agreement [Member] | Research and Development Expense [Member] | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment of Milestones			$ 364,500
Viracta License Agreement [Member] | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment of Milestones		$ 54,000
Viracta License Agreement [Member] | Research and Development Expense [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment of Milestones		$ 3,000
Upfront of cash payment	$ 2,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Apr. 30, 2022 USD ($) ft²	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Lessee Lease Description [Line Items]
Weighted-average remaining lease term		1 year 10 months 24 days
Weighted-average discount rate		9%
Amortization of operating right-of-use assets		$ 468,000	$ 179,000	$ 139,000
Research And Development Agreements
Lessee Lease Description [Line Items]
Termination and cancellation charges payable		0	0
Viracta License Agreement [Member]
Lessee Lease Description [Line Items]
Royalty fee payable		0	0
Indemnification Agreement
Lessee Lease Description [Line Items]
Termination and cancellation charges payable		0	0
Central America
Lessee Lease Description [Line Items]
Operating lease term	31 months
Area of land | ft²	12,000
Security deposit	$ 40,000
Operating lease payments	$ 1,100,000
Lease For Corporate Office Facility | Central America
Lessee Lease Description [Line Items]
Tenant improvement allowances receivable		$ 10,000
Lessee operating lease renewal lease term		3 years
Amortization of operating right-of-use assets		$ 500,000	200,000	100,000
Operating lease payments		$ 400,000	$ 200,000	$ 200,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Future Lease Obligations (Detail) $ in Thousands	Dec. 31, 2022 USD ($)
Lessee Lease Description [Line Items]
2023	$ 458
2024	424
Total future minimum lease payments	882
Less: Imputed interest	69
Present value of operating lease liabilities	$ 813

Redeemable Convertible Prefer_2

Redeemable Convertible Preferred Shares - Additional Information (Detail) - USD ($)		1 Months Ended
	Jun. 01, 2021	Jun. 30, 2021	Feb. 28, 2021	Dec. 31, 2022
Temporary Equity [Line Items]
Payments of Stock Issuance Costs	$ 17,000,000
Redeemable Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Common Stock Shares Issued As A Result Of Conversion Of Temporary Equity Into Permanent Equity		32,489,398
Temporary Equity, Shares Outstanding				0
Series B Redeemable Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary Equity Stock Issued During The Period Shares New Issues			9,638,141
Temporary Equity Issue Price Per Share			$ 13.488
Payments of Stock Issuance Costs			$ 243,000
Series B Redeemable Convertible Preferred Stock [Member] | Gross Proceeds [Member]
Temporary Equity [Line Items]
Proceeds from redeemable convertible preferred stock			$ 130,000,000
IPO [Member]
Temporary Equity [Line Items]
Stock Issued During Period, Shares, New Issues	11,500,000	11,500,000

Common Stock - Additional Infor

Common Stock - Additional Information (Detail) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Jun. 30, 2022 USD ($) $ / shares shares	Nov. 30, 2018 USD ($) shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($)
Class Of Stock [Line Items]
Common Stock, Shares Authorized			500,000,000	500,000,000
Common Stock, Par or Stated Value Per Share | $ / shares			$ 0.0001	$ 0.0001
Common Stock, Shares, Issued			73,458,176	61,952,292
Common Stock, Shares, Outstanding			73,458,176	61,952,292
Number Of Directors Entitled To Be Elected By The Holders Of Common Stock		200
Common Stock, capital shares purchase an additional for future issuance			11,061,049
Proceeds from issuance of common stock, net | $			$ 161,610	$ 167,045	$ 0
Common Stock, Capital Shares Reserved for Future Issuance			11,061,049
Proceeds from Issuance of Common Stock | $			$ 161,610	$ 167,045	$ 0
Common Shares Purchase Agreement
Class Of Stock [Line Items]
Common Stock, Shares Authorized			500,000,000
Common Stock, Par or Stated Value Per Share | $ / shares			$ 0.0001
Common Stock, Shares, Issued			73,458,176
Common Shares Purchase Agreement | Founder
Class Of Stock [Line Items]
Stock Issued During Period, Shares, New Issues		2,790,000
Proceeds from issuance of common stock, net | $		$ 300
Proceeds from Issuance of Common Stock | $		$ 300
Sales agreement [Member]
Class Of Stock [Line Items]
Common Stock, Par or Stated Value Per Share | $ / shares	$ 15
Common Stock, Shares, Issued	11,500,000
Common Stock, capital shares purchase an additional for future issuance	1,500,000
Proceeds from issuance of common stock, net | $	$ 161,600
Common stock for an aggregate offering price | $	$ 150,000
Common Stock, Capital Shares Reserved for Future Issuance	1,500,000
Proceeds from Issuance of Common Stock | $	$ 161,600

Common Stock - Schedule of Comm

Common Stock - Schedule of Common Stock Shares Reserved for Future Issuance (Detail)	Dec. 31, 2022 shares
Class Of Stock [Line Items]
Common Stock, capital shares purchase an additional for future issuance	11,061,049
Common Stock [Member]
Class Of Stock [Line Items]
Common Stock, capital shares purchase an additional for future issuance	7,634,167
Restricted Stock Units (RSUs) [Member]
Class Of Stock [Line Items]
Common Stock, capital shares purchase an additional for future issuance	485,351
Share-based Payment Arrangement, Option [Member]
Class Of Stock [Line Items]
Common Stock, capital shares purchase an additional for future issuance	1,101,756
Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Common Stock, capital shares purchase an additional for future issuance	1,839,775

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	May 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Oct. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, capital shares purchase an additional for future issuance		11,061,049
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares		4,719,605
Share-based compensation expense		$ 27,242	$ 13,321	$ 526
Performance Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted		152,550
Total fair value of options		$ 1,200
Weighted-average grant date fair value of options granted		$ 7.78
Performance Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of options		$ 1,500
Granted PSUs		99,250
Grant date fair value		$ 15.25
Incentive Share Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation remaining period for recognition		3 years 9 months 18 days
Unamortized stock-based compensation for stock options		$ 4,500
Incentive Share Plan [Member] | Day One Holding LLC [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangment number of shares authorized		8,924,177
2021 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, capital shares purchase an additional for future issuance	6,369,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares	4,719,605	7,634,167
Granted		3,284,580
Total intrinsic value of the options outstanding		$ 40,759
Total fair value of options		$ 23,100	$ 1,100
Weighted-average grant date fair value of options granted		$ 9.61	$ 9.91
Weighted average remaining contractual term		8 years 9 months 18 days
Weighted-average period expected to be recognized		8 years 9 months 18 days
2021 Equity Incentive Plan [Member] | Unvested Restricted Stock And Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period expected to be recognized		3 years 3 months 18 days
Unamortized stock-based compensation for stock options		$ 7,500
2021 Equity Incentive Plan [Member] | Performance Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period expected to be recognized		2 years 8 months 12 days
Unamortized stock-based compensation for stock options		$ 49,800
2021 Equity Incentive Plan [Member] | Incremental Shares Reserved For Future Issuance
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum	5%
2021 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment award fair value assumptions dividend yield		0%	0%
Common Stock, capital shares purchase an additional for future issuance	603,000
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum	1%
Stock Issued During Period, Shares, Employee Stock Ownership Plan		97,413
Share-based compensation expense		$ 500	$ 200
2021 Employee Stock Purchase Plan [Member] | Unvested Restricted Stock And Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation		$ 70,100
Share based compensation by share based payment arrangement unrecognized compensation remaining period for recognition		2 years 9 months 18 days
2021 Employee Stock Purchase Plan [Member] | Unvested PSOs and PSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation		$ 2,600
2022 Equity Inducement Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, capital shares purchase an additional for future issuance					1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares		309,000
Granted		309,000
Total intrinsic value of the options outstanding		$ 117
Total fair value of options		$ 0	$ 0	$ 0
Weighted-average grant date fair value of options granted		$ 15.08	$ 0	$ 0
Weighted average remaining contractual term		9 years 9 months 18 days
Weighted-average period expected to be recognized		9 years 9 months 18 days
2022 Equity Inducement Plan [Member] | Unvested Restricted Stock And Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period expected to be recognized		3 years 10 months 24 days
Unamortized stock-based compensation for stock options		$ 1,000

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Fair Value of The Incentive Shares Estimated Using An Option Pricing Model (Detail) - Incentive Share Plan Member [Member] - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Participating threshold		$ 0.27
Risk free rate	0.14%
Volatility	72.90%
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common share fair value	$ 6.36	$ 0.85
Participating threshold	$ 6.36
Risk free rate		0.16%
Volatility		78%
Time to liquidity (in years)	2 months 12 days	3 years 10 days
Grant date fair value	$ 4.24	$ 0.71
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common share fair value	8.89	$ 2.10
Participating threshold	$ 7.51
Risk free rate		0.30%
Volatility		80%
Time to liquidity (in years)	1 year 9 months 18 days	3 years 3 months 29 days
Grant date fair value	$ 4.52	$ 1.67

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of The Incentive Shares Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Two Thousand And Twenty One Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Forfeited	(406,444)
Number of Shares, Unvasted Restricted Stock, Beginning balance	3,753,862
Weighted Average Grant Date Fair Value, Beginning Balance	$ 16
Weighted Average Grant Date Fair Value, Ending Balance	$ 16	$ 16
Incentive Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Share Outstanding, Beginning balance	0	4,112,017
Granted		2,959,795
Forfeited		(265,596)
Converted to unvested common stock		(6,806,216)
Number of Share Outstanding, Ending balance		0
Weighted Average Grant Date Fair Value, Beginning Balance	$ 0	$ 1.26
Grant date fair value		4.32
Forfeited		1.67
Converted to unvested common stock		2.58
Weighted Average Grant Date Fair Value, Ending Balance		$ 0

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	May 31, 2021	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested and expected to vest at December 31, 2022		4,719,605
2021 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Beginning Balance		5,071,896
Granted		3,284,580
Exercised		(235,474)
Forfeiture		(486,835)
Number of Shares, Ending Balance		7,634,167
Vested and expected to vest at December 31, 2022	4,719,605	7,634,167
Exercisable at December 31, 2022		2,287,512
Weighted Average Exercise Price, Begining Balance		$ 16.90
Granted		15.45
Exercised		15.70
Forfeiture		15.17
Weighted Average Exercise Price, Ending Balance		16.42
Vested and expected to vest at December 31, 2022		16.42
Exercisable at December 31, 2022		$ 16.46
Weighted-Average Remaining Contractual Term, Outstanding at December 31, 2021		8 years 9 months 18 days
Vested and expected to vest at December 31, 2022		8 years 9 months 18 days
Weighted-Average Remaining Contractual Term, Exercisable at December 31, 2021		8 years 7 months 6 days
Exercised		$ 1,604
Outstanding at December 31, 2022, Aggregiate Intrinsic Value		40,759
Vested and expected to vest at December 31, 2022		40,759
Exercisable at December 31, 2022, Aggregiate Intrinsic Value		$ 12,050
2022 Equity Inducement Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted		309,000
Number of Shares, Ending Balance		309,000
Vested and expected to vest at December 31, 2022		309,000
Granted		$ 21.14
Weighted Average Exercise Price, Ending Balance		21.14
Vested and expected to vest at December 31, 2022		$ 21.14
Weighted-Average Remaining Contractual Term, Outstanding at December 31, 2021		9 years 9 months 18 days
Vested and expected to vest at December 31, 2022		9 years 9 months 18 days
Outstanding at December 31, 2022, Aggregiate Intrinsic Value		$ 117
Vested and expected to vest at December 31, 2022		$ 117

Stock-Based Compensation - Su_4

Stock-Based Compensation - Summary of The Black-Scholes Option Pricing Model to Estimate The Fair Value of Stock Option Granted (Detail)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
2021 Equity Incentive Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 7 days	5 years 3 months 21 days
Expected volatility	65.20%	61.25%
Risk-free interest rate	1.47%	0.82%
2021 Equity Incentive Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 3 months 29 days	6 years 29 days
Expected volatility	81.68%	66.53%
Risk-free interest rate	4.37%	1.39%
2022 Equity Inducement Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 29 days
Expected volatility	79.53%
Risk-free interest rate	4.18%
2021 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months
Expected volatility	128.95%
Risk-free interest rate	4.54%
Share based compensation by share based payment award fair value assumptions dividend yield	0%	0%
2021 Employee Stock Purchase Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		3 months
Expected volatility		42.50%
Risk-free interest rate		0.05%
2021 Employee Stock Purchase Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		6 months
Expected volatility		48.40%
Risk-free interest rate		0.06%
Performance Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	3.37%
Performance Stock Options | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	2 years 11 months 1 day
Expected volatility	72.72%
Performance Stock Options | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	3 years 5 months 1 day
Expected volatility	72.98%

Stock-Based Compensation - Su_5

Stock-Based Compensation - Summary of Restricted Stock Units Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
2021 Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vested	1,624,674
Forfeited	406,444
Unvested restricted stock as of December 31, 2022	$ 16	$ 16
Vested	16
Unvested restricted stock Grant fair value at December 31, 2022	$ 16	$ 16
2021 Stock Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unvested restricted stock at December 31, 2021		96,890
Granted PSUs	503,095
Vested	79,441
Forfeited	35,193
Unvested restricted stock at December 31, 2022	485,351
Unvested restricted stock as of December 31, 2022	$ 16.83	$ 22.93
Grant date fair value	15.47
Vested	16.82
Forfeited	14.14
Unvested restricted stock Grant fair value at December 31, 2022	$ 16.83	$ 22.93
2022 Equity Inducement Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted PSUs	47,400
Unvested restricted stock at December 31, 2022	47,400
Unvested restricted stock as of December 31, 2022	$ 21.14
Grant date fair value	21.14
Unvested restricted stock Grant fair value at December 31, 2022	$ 21.14

Stock-Based Compensation - Su_6

Stock-Based Compensation - Summary of The Unvested Common Stock (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
2021 Stock Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvasted Restricted Stock, Beginning balance	3,753,862
Vested	(1,624,674)
Forfeited	(406,444)
Number of Shares, Unvasted Restricted Stock, Ending balance	1,722,744	3,753,862
Weighted Average Grant Date Fair Value, Beginning Balance	$ 16
Conversion of incentive shares	16
Vested	16
Weighted Average Grant Date Fair Value, Ending Balance	16	$ 16
Incentive Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding as of December 31, 2020		0	4,112,017
Forfeited		(265,596)
Number of Share Outstanding, Ending balance		0
Weighted Average Grant Date Fair Value, Beginning Balance	$ 0	$ 1.26
Weighted Average Grant Date Fair Value, Ending Balance		$ 0

Stock-Based Compensation - Su_7

Stock-Based Compensation - Summary of Share/Stock-based Compensation Expense Recorded in The Accompanying Condensed Consolidated Statements of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 27,242	$ 13,321	$ 526
2021 Employee Stock Purchase Plan [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	500	200
Research and Development Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	8,486	3,840	212
General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 18,756	$ 9,481	$ 314

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Basic and Diluted Net Loss Per Share Attributable to Common Shareholders/Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Net loss	$ (142,181)	$ (72,754)	$ (43,843)
Net loss attributable to redeemable convertible noncontrolling interests	0	(2,109)	(3,336)
Exchange of redeemable noncontrolling interest shares - deemed dividend	0	(99,994)	0
Net loss attributable to common share members/common stockholders	$ (142,181)	$ (170,639)	$ (40,507)
Net loss per share, diluted	$ (2.17)	$ (4.62)	$ (7.33)
Net loss per share, basic	$ (2.17)	$ (4.62)	$ (7.33)
Weighted-average number of common shares used in computing net loss per share, diluted	65,466,773	36,960,569	5,529,519
Weighted-average number of common shares used in computing net loss per share, basic	65,466,773	36,960,569	5,529,519

Net Loss Per Share - Summary _2

Net Loss Per Share - Summary of Outstanding Potentially Dilutive Securities Have Been Excluded From Calculation of Diluted Net Loss Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	10,243,334	8,948,010	27,157,040
Share-based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	7,943,167	5,071,896	0
Unvested common shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	1,722,744	3,753,862	193,766
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	532,751	96,890	0
Shares committed under ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	44,672	25,362	0
Incentive Shares [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	0	0	4,112,017
Redeemable convertible preferred shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options	0	0	22,851,257

Redeemable Noncontrolling Int_2

Redeemable Noncontrolling Interest - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	5 Months Ended	12 Months Ended
	May 26, 2021	May 26, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Redeemable Noncontrolling Interest [Line Items]
Net loss attributable to redeemable convertible noncontrolling interests			$ 0	$ (2,109)	$ (3,336)
Adjustment To Additional Paid In Capital Loss On Conversion Of Temporary Equity Into Permanent Equity		$ 100,000
DOT One [Member]
Redeemable Noncontrolling Interest [Line Items]
Temporary Equity Shares Converted Into Permanent Equity	9,857,143
Common Stock Shares Issued As A Result Of Conversion Of Temporary Equity Into Permanent Equity	6,470,382
DOT One [Member] | Takeda [Member]
Redeemable Noncontrolling Interest [Line Items]
Net loss attributable to redeemable convertible noncontrolling interests		$ 2,100

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Detail)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Statutory rate	21%	21%	21%
State tax	0.60%	(0.80%)	2.30%
Permanent differences	0%	0.60%	(14.40%)
Credits	1.70%	3.80%	1.40%
Change in valuation allowance	(22.60%)	(21.50%)	(10.10%)
Share-based compensation	(0.70%)	(3.10%)	(0.20%)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets
Federal and state net operating loss carryforwards	$ 25,884	$ 17,270	$ 7,732
Capitalized R&D Section 174 Expense	14,908	0	0
Credits	6,653	3,670	731
Intangible asset basis	2,562	2,188	0
Share-based compensation	2,133	0	0
Accrued expenses	1,803	709	235
Total deferred tax assets	53,943	23,837	8,698
Total deferred tax liabilities	(149)	(59)	(97)
Less: valuation allowance	(53,794)	(23,778)	(8,601)
Net deferred tax assets	$ 0	$ 0	$ 0

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Change in deferred tax assets valuation allowance	$ 30,000	$ 15,200	$ 4,400
Operating Loss Carryforwards	117,600
Offset tax liabilities	$ 8,200
Net Operating Loss, Carryback period	12 months
Net operating loss carryforwards	$ 117,600
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	0	$ 0	$ 0
Tax Credit Carryforward, Expiration Year
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Tax Credit Carryforward, Expiration Year	2038
Research and experimental expenses amortization period	5 years
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Research and experimental expenses amortization period	15 years
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
State tax credits	$ 1,200
Gross state NOL	$ 17,600
Tax Credit Carryforward, Expiration Year	2038
Tax Credit Carryforward, Expiration Year

Income Taxes - Summary of Unrec

Income Taxes - Summary of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 1,141	$ 188	$ 2
Additions based on tax positions related to prior year	726	0	0
Additions based on tax positions related to current year	916	953	186
Reductions based on tax positions related to prior year	(248)	0	0
Reductions based on tax positions related to current year	0	0	0
Balance at end of year	$ 2,535	$ 1,141	$ 188

Defined Contribution Plan (Addi

Defined Contribution Plan (Additional Information) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)
Retirement Benefits [Abstract]
Matching Contribution	$ 0.8