Acrivon Therapeutics, Inc. Common Stock (ACRV) 10-K 28 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 25, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Trading Symbol	ACRV
Entity Registrant Name	Acrivon Therapeutics, Inc.
Entity Central Index Key	0001781174
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Common Stock, Shares Outstanding		22,636,951
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-41551
Entity Tax Identification Number	82-5125532
Entity Address, Address Line One	480 Arsenal Way
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Watertown
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02472
City Area Code	617
Local Phone Number	207-8979
Entity Incorporation, State or Country Code	DE
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.001 per share
Security Exchange Name	NASDAQ
Document Annual Report	true
Document Transition Report	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction	false
Documents Incorporated by Reference	Portions of the Registrant's definitive Proxy Statement, to be filed pursuant to Regulation 14A under the Securities Exchange Act of 1934, for its 2024 Annual Meeting of Stockholders are incorporated herein by reference in Part III.
Auditor Firm ID	238
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Boston, Massachusetts, United States
Entity Public Float			$ 157.7

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 36,015	$ 29,519
Short-term investments	91,443	98,232
Prepaid expenses and other current assets	2,234	4,344
Total current assets	129,692	132,095
Property and equipment, net	3,479	2,092
Operating lease right-of-use assets	4,429	4,770
Long-term investments		41,881
Restricted cash	414	388
Deferred offering costs	251
Total assets	138,265	181,226
Current liabilities:
Accounts payable	5,048	904
Accrued expenses and other current liabilities	7,378	4,886
Operating lease liabilities, current	877	726
Total current liabilities	13,303	6,516
Operating lease liabilities, long-term	3,767	4,235
Total liabilities	17,070	10,751
Commitments and contingencies (Note 12)
Stockholders' equity:
Common stock, par value $0.001; 500,000,000 shares authorized as of December 31, 2023 and 2022, respectively; 22,522,644 and 21,920,402 shares issued and outstanding as of December 31, 2023 and 2022, respectively.	23	22
Additional paid-in capital	237,675	226,580
Accumulated other comprehensive loss	(83)	(95)
Accumulated deficit	(116,420)	(56,032)
Total stockholders' equity	121,195	170,475
Total liabilities and stockholders' equity	$ 138,265	$ 181,226

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, authorized	10,000,000	10,000,000
Preferred stock, shares, issued	0	0
Preferred stock, shares, outstanding	0	0
Common stock, per share value	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares, issued	22,522,644	21,920,402
Common stock, shares, outstanding	22,522,644	21,920,402

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating expenses:
Research and development	$ 46,024	$ 23,949
General and administrative	21,079	8,708
Total operating expenses	67,103	32,657
Loss from operations	(67,103)	(32,657)
Other income, net	6,715	1,490
Net loss	$ (60,388)	$ (31,167)
Net loss per share—basic	$ (2.74)	$ (7.56)
Net loss per share—diluted	$ (2.74)	$ (7.56)
Weighted-average common stock outstanding—basic	22,078,190	4,121,912
Weighted-average common stock outstanding—diluted	22,078,190	4,121,912
Comprehensive loss:
Net loss	$ (60,388)	$ (31,167)
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale investments, net of tax	12	(95)
Comprehensive loss	$ (60,376)	$ (31,262)

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' DEFICIT - USD ($) $ in Thousands	Total	IPO [Member]	Private Placement [Member]	Convertible Preferred Stock	Common Stock	Common Stock IPO [Member]	Common Stock Private Placement [Member]	Additional Paid-In Capital	Additional Paid-In Capital IPO [Member]	Additional Paid-In Capital Private Placement [Member]	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning Balance at Dec. 31, 2021	$ (23,809)				$ 2			$ 1,054				$ (24,865)
Beginning Balance of Temporary Equity, Shares at Dec. 31, 2021				27,471,911
Beginning Balance of Temporary Equity, Value at Dec. 31, 2021				$ 122,518
Beginning Balance, Shares at Dec. 31, 2021					1,769,561
Issuance of common stock		$ 96,169	$ 4,650			$ 9			$ 96,160	$ 4,650
Issuance of common stock, Shares						8,585,540	400,000
Exercise of common stock options	24							24
Exercise of common stock options, Shares					25,039
Conversion of convertible preferred stock to common stock, Shares				(27,471,911)	11,140,262
Conversion of convertible preferred stock to common stock	122,518			$ (122,518)	$ 11			122,507
Stock-based compensation expense	2,185							2,185
Unrealized gain (loss) on available-for-sale investments, net of tax	(95)										$ (95)
Net loss	(31,167)											(31,167)
Ending Balance at Dec. 31, 2022	170,475				$ 22			226,580			(95)	(56,032)
Ending Balance, Shares at Dec. 31, 2022					21,920,402
Exercise of common stock options	$ 775							775
Exercise of common stock options, Shares	292,444				292,444
Issuance of common stock upon vesting of restricted stock units, net of shares withheld for tax	$ (1,297)				$ 1			(1,298)
Issuance of common stock upon vesting of restricted stock units, net of shares withheld for tax, Shares					309,798
Stock-based compensation expense	11,618							11,618
Unrealized gain (loss) on available-for-sale investments, net of tax	12										12
Net loss	(60,388)											(60,388)
Ending Balance at Dec. 31, 2023	$ 121,195				$ 23			$ 237,675			$ (83)	$ (116,420)
Ending Balance, Shares at Dec. 31, 2023					22,522,644

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (60,388)	$ (31,167)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	536	364
Stock-based compensation expense	11,618	2,185
Non-cash lease expense	778	731
Net amortization of premiums and accretion of discounts on investments	(3,323)	(698)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	2,110	(3,539)
Accounts payable	3,609	(245)
Accrued expenses and other liabilities	3,173	2,919
Operating lease liabilities	(754)	(667)
Net cash used in operating activities	(42,641)	(30,117)
Cash flows from investing activities:
Purchases of short-term and long-term investments	(56,528)	(150,178)
Proceeds from maturities of short-term investments	108,533	10,668
Purchases of property and equipment	(1,288)	(2,166)
Net cash provided by (used in) investing activities	50,717	(141,676)
Cash flows from financing activities:
Proceeds from initial public offering of common stock, net of commissions and underwriting discounts		99,808
Proceeds from issuance of common stock upon Concurrent Private Placement, net of placement agent fee		4,650
Proceeds from exercise of stock options	775	24
Payments of offering costs	(1,032)	(2,773)
Payments of tax withholdings related to vesting of restricted stock units	(1,297)
Net cash (used in) provided by financing activities	(1,554)	101,709
Net increase (decrease) in cash, cash equivalents, and restricted cash	6,522	(70,084)
Cash, cash equivalents and restricted cash at beginning of period	29,907	99,991
Cash, cash equivalents and restricted cash at end of period	36,429	29,907
Supplemental disclosure of non-cash investing and financing activities:
Conversion of convertible preferred stock to common stock		122,518
Purchases of property and equipment included in accounts payable	635
Supplemental cash flow information:
Right-of-use assets obtained in exchange for operating lease liability	437
Deferred offering costs in accounts payable and accrued expenses and other current liabilities	85	866
Reconciliation of cash, cash equivalents, and restricted cash:
Cash and cash equivalents	36,015	29,519
Restricted cash	414	388
Total cash, cash equivalents, and restricted cash	$ 36,429	$ 29,907

Nature of the Business

Nature of the Business	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business	1. Nature of the Business Acrivon Therapeutics, Inc., (the “Company”) is a clinical stage biopharmaceutical company developing oncology medicines that the Company matches to patients whose tumors are predicted to be sensitive to each specific medicine by utilizing its proteomics-based patient responder identification platform. The Company’s pipeline includes the Phase 2 lead program, ACR-368, referred to as prexasertib, a precision oncology asset, as well as ACR-2316, a selective, dual WEE1/PKMYT1 inhibitor, and additional programs targeting these two critical nodes in the DNA Damage Response, or DDR, pathways. The Company was incorporated in March 2018 under the laws of the state of Delaware, and its principal offices are in Watertown, Massachusetts. Also in March 2018, the Company formed Acrivon AB, a wholly-owned subsidiary of the Company, established in Lund, Sweden. In December 2021, the Company formed Acrivon Securities Corporation, a wholly-owned subsidiary, established in Massachusetts. Liquidity As an emerging growth entity, the Company has devoted substantially all of its resources since inception to organizing and staffing the Company, business planning, raising capital, establishing its intellectual property portfolio, acquiring or discovering drug candidates, research and development activities for the Company's lead candidate ACR-368, for the Company's internally discovered development candidate ACR-2316, and other compounds, establishing arrangements with third parties for the manufacture of its drug candidates and component materials, and providing general and administrative support for these operations. As a result, the Company has incurred significant operating losses and negative cash flows from operations since its inception and anticipates such losses and negative cash flows will continue for the foreseeable future. The Company has incurred recurring losses since its inception, including net losses of $ 60.4 million and $ 31.2 million for the years ended December 31, 2023, and 2022, respectively. As of December 31, 2023 and 2022 the Company had an accumulated deficit of $ 116.4 million and $ 56.0 million, respectively. To date the Company has not generated any revenues and expects to continue generating operating losses for the foreseeable future as it continues to expand its research and development efforts. Since its inception, the Company has funded its operations primarily with proceeds from the sales of shares of its convertible preferred stock and the issuance of convertible notes, and most recently, through an initial public offering (“IPO”) and concurrent private placement. Upon the closing of the Company’s IPO on November 17, 2022, only common stock remains issued and outstanding. The Company expects that its existing cash, cash equivalents and investments of $ 127.5 million as of December 31, 2023, will be sufficient to fund its operating expenses and capital expenditure requirements for at least 12 months from the date these consolidated financial statements were issued. The Company will need additional funding to support its planned operating activities. There can be no assurances, however, that the current operating plan will be achieved or that additional funding will be available on terms acceptable to the Company, or at all, considering the current interest rate environment. If the Company is unable to obtain sufficient funding, it could be required to delay its development efforts, limit activities and reduce research and development costs, which could adversely affect its business prospects. ATM Program On December 1, 2023, the Company filed a registration statement on Form S-3 (the “Registration Statement”) with the U.S. Securities and Exchange Commission (the “SEC”), which was declared effective on December 15, 2023, which registered the offering, issuance, and sale of up to a maximum aggregate offering price of $ 300.0 million of common stock, preferred stock, debt securities, warrants and/or units of any combination thereof. We simultaneously entered into a sales agreement with Cowen and Company, LLC, as sales agent, to provide for the issuance and sale by the Company of up to $ 100.0 million of common stock from time to time in “at-the-market” offerings under the Registration Statement and related prospectus filed with the Registration Statement (“ATM Program”). As of December 31, 2023, no sales had been made pursuant to the ATM Program. Initial Public Offering, Reverse Stock Split and Concurrent Private Placement On November 17, 2022, the Company closed its IPO, pursuant to which it issued and sold 7,550,000 shares of its common stock at a public offering price of $ 12.50 per share for gross proceeds of $ 94.4 million. In connection with the IPO, the Company granted the underwriters a 30-day option to purchase 1,132,500 additional shares of common stock. On December 14, 2022, the underwriters partially exercised the option to purchase 1,035,540 additional shares. The sale pursuant to the exercise of the underwriters’ option to purchase additional shares closed on December 16, 2022, upon which the Company issued 1,035,540 shares of common stock for gross proceeds of $ 12.9 million. The Company received aggregate net proceeds from the IPO, including the exercise by the underwriters of their option to purchase additional shares, of $ 99.8 million, after deducting underwriting discounts and commissions of $ 7.5 million, but before deducting offering expenses payable by the Company of $ 3.6 million. In connection with the IPO, the Company effected a 1-for-2.466 reverse stock split of the Company’s common stock and adjusted the ratio at which the Company’s preferred stock is convertible into common stock, the number of shares available for issuance under the 2019 Stock Incentive Plan (“2019 Plan”) and the number of options and exercise prices of options granted under the 2019 Plan as a result of the 1-for-2.466 reverse stock split. Accordingly, all common shares, stock options, and per share information presented in the accompanying consolidated financial statements and notes thereto have been adjusted, where applicable, to reflect the reverse stock split on a retroactive basis for all periods presented. The per share par value and authorized number of shares of the Company’s common stock were not adjusted as a result of the reverse stock split. Upon the closing of the IPO, all of the Company's then-outstanding shares of convertible preferred stock converted into 11,140,262 shares of common stock at the applicable conversion ratio then in effect. Subsequent to the closing of the IPO, there were no shares of convertible preferred stock outstanding. The Company also completed a private placement which closed concurrently with the IPO, in which the Company issued and sold 400,000 shares of its common stock at $ 12.50 per share to Chione Limited, an existing investor of the Company (the “Concurrent Private Placement”). The Company received aggregate net proceeds of $ 4.7 million from the Concurrent Private Placement, after deducting the placement agent fee.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation and Consolidation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include the operations of Acrivon Therapeutics, Inc. and its wholly-owned subsidiaries. All intercompany accounts, transactions and balances have been eliminated in consolidation. Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the accrual of research and development expenses and the valuation of stock-based awards. The Company bases its estimates on historical experience when available, known trends and other market specific data, or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates when there are changes in circumstances, facts and experience. Changes in estimates and assumptions are reflected in reported results in the period in which they become known. Actual results could differ from those estimates. Segment Information Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one operating segment. The Company’s focus is the research and development of precision oncology therapies. The Company’s chief operating decision maker, its chief executive officer, manages the Company’s operations on a consolidated basis for the purpose of allocating resources. As the Company has one reportable segment, all required segment financial information is presented in the consolidated financial statements. As of December 31, 2023, $ 5.7 million and $ 2.2 million of the Company’s long-lived assets are held in the United States and in Sweden, respectively. Cash and Cash Equivalents The Company considers all highly liquid investments purchased with original maturities of 90 days or less at acquisition to be cash equivalents. Cash and cash equivalents include standard checking accounts and amounts held in money market funds. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. Restricted Cash Cash accounts with any type of restriction are classified as restricted cash. The Company has restricted cash deposits with a bank, which serve as collateral for a letter of credit issued to the landlord of the Company’s leased facility for a security deposit. The Company classified this amount as restricted cash in the accompanying consolidated balance sheets within non-current assets based on the release date of restrictions. Deferred Offering Costs The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of an equity financing, these costs are recorded as a reduction of the proceeds from the offering in stockholders’ equity as a reduction of additional paid-in capital generated as a result of the offering. Should the Company choose to not initiate such financing, the deferred offering costs would be immediately expensed as operating expenses. Deferred offering costs associated with the ATM Program are reclassified to additional paid-in-capital on a pro-rata basis when the Company completes offerings under the ATM Program. Any remaining deferred offering costs will be expensed to the consolidated statements of operations and comprehensive loss should the planned offering be abandoned. As of December 31, 2023, $ 0.3 million of such deferred offering costs are capitalized. Concentration of Credit Risk and Significant Suppliers Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and investments. The Company has not experienced any credit losses on its cash, cash equivalents, or investments. The Company maintains its cash, cash equivalents and investments, which at times exceed insurance limits, at major financial institutions. The Company has not experienced any losses in such accounts and management believes that such funds are not exposed to any significant credit or concentration risk. However, the Company may face exposure, including constraint on liquidity and access to capital, if there is failure by these or other financial institutions. The Company is dependent on third-party contract research organizations (“CROs”) and contract manufacturing organizations to supply certain intellectual property and services for research activities in its drug candidates. In particular, the Company relies and expects to continue to rely on a small number of these organizations to supply it with its requirements for key raw materials related to these programs. These drug candidates could be adversely affected by a significant interruption in the supply of key raw materials. Additionally, the Company relies on a single companion diagnostic collaborator to perform ACR-368 OncoSignature tests in the Company’s clinical trials (see Note 12). Comprehensive Loss Comprehensive loss is defined as a change in equity of a business enterprise during a period resulting from transactions from non-owner sources. Comprehensive loss includes net loss and certain changes in stockholders' equity that are excluded from net loss. The Company had a net change in available-for-sale securities during the years ended December 31, 2023 and 2022, which met the criteria as other comprehensive loss and, therefore, the Company’s comprehensive loss includes unrealized gains (losses) on those available-for-sale securities. Investments The Company classifies all investments with an original maturity of greater than three months and less than one year upon purchase as available-for-sale. Available-for-sale securities are recorded at fair value based upon market prices at period end, with the unrealized gains and losses reported in other comprehensive loss. The amortized cost of debt securities in this category is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization is included in interest income, presented within other income, net in the consolidated statements of operations and comprehensive loss. Realized gains and losses and declines in value due to credit-related factors on available-for-sale securities are included in other income, net in the consolidated statements of operations and comprehensive loss. The cost of securities sold is based on the specific identification method. Interest on securities classified as available-for-sale is included in interest income, presented within other income, net in the consolidated statements of operations and comprehensive loss. For the years ended December 31, 2023 and 2022, other income, net, of $ 6.7 million and $ 1.5 million, respectively, included interest income of $ 7.0 million and $ 1.5 million, respectively, offset by de minimis miscellaneous items. At each balance sheet date, the Company assesses available-for-sale debt securities in an unrealized loss position to determine whether the unrealized loss or any potential credit losses should be recognized in other income, net. The Company evaluates whether it intends to sell, or it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. The Company also evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the severity of the impairment, any changes in interest rates, changes to the underlying credit ratings and forecasted recovery, among other factors. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded in other income, net. There have been no impairment or credit losses recognized during any of the periods presented. Fair Value Measurements Accounting Standards Codification (“ASC”) Topic 820, Fair Value Measurement (“ASC 820”), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company’s own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tier fair value hierarchy that distinguishes among the following: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. Level 3 —Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. 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. Property and Equipment, net Property and equipment are stated at cost, less accumulated depreciation. Costs for capital assets not yet placed in service are capitalized as construction in progress and depreciated once placed in service. Costs of major additions and betterments are capitalized. Maintenance and repairs which do not improve or extend the life of the respective assets are charged to expense as incurred. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets, which range from five to seven years. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. The Company's leasehold improvements as of December 31, 2023 were de minimis. The Company had no leasehold improvements as of December 31, 2022. When an item is sold or retired, the costs and related accumulated depreciation are eliminated, and the resulting gain or loss, if any, is credited or charged to the consolidated statements of operations and comprehensive loss. Property and equipment to be disposed of are carried at fair value less costs to sell. The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life (in Years) Laboratory equipment and computer equipment 5 years Furniture and fixtures 5 - 7 years Leasehold improvements Lesser of asset useful life or lease term Impairment of Long-Lived Assets The Company recognizes an impairment loss in the consolidated statements of operations and comprehensive loss only if the carrying amount of a long-lived asset is not recoverable based on its undiscounted future cash flows and in such case, measures an impairment loss as the difference between the carrying amount and the fair value of the asset. The Company tests long-lived assets to be held and used, including property and equipment and operating lease right-of-use (“ROU”) assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of assets or asset groups may not be fully recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written down to their fair values. The Company has no t recognized any impairment losses during the years ended December 31, 2023 and 2022. Research and Development Expenses Research and development costs include (i) employee-related expenses, including salaries, benefits, and stock-based compensation expense; (ii) external research and development expenses incurred under arrangements with third parties, such as CRO agreements and consultants; (iii) costs associated with preclinical activities; and (iv) lab supplies, lab expenses and an allocation of rent, depreciation, and infrastructure. Costs incurred in connection with research and development activities are expensed as incurred. The Company enters into various consulting, research, and other agreements with commercial firms, researchers, universities and other external parties for the provision of goods and services. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the Company’s clinical sites and vendors. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. Depending upon the timing of payments to the service providers, the Company recognizes prepaid expenses or accrued expenses related to these costs. These accrued or prepaid expenses are based on management’s estimates of the work performed under service agreements, milestones achieved, and experience with similar contracts. Milestone payments under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. The Company monitors each of these factors and adjusts estimates accordingly. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception. Asset Acquisitions and Acquired In-Process Research and Development Expenses The Company accounts for acquisitions of assets or a group of assets that do not meet the definition of a business as asset acquisitions based on the cost to acquire the asset or group of assets, which include certain transaction costs. In an asset acquisition, the cost to acquire is allocated to the identifiable assets acquired and liabilities assumed based on their relative fair values as of the acquisition date. No goodwill is recorded in an asset acquisition. Assets that are acquired in an asset acquisition for use in research and development activities that have an alternative future use are capitalized as in-process research and development (“IPR&D”). Acquired IPR&D that has no alternative future use as of the acquisition date is recognized as research and development expense as of the acquisition date. The Company will recognize additional research and development expenses in the future if and when the Company becomes obligated to make contingent milestone payments under the terms of the agreements by which it acquired the IPR&D assets. Contingent consideration in asset acquisitions is measured and recognized when payment becomes probable and reasonably estimable. Subsequent changes in the accrued amount of contingent consideration are measured and recognized at the end of each reporting period and upon settlement as an adjustment to the cost basis of the acquired asset or group of assets, or, if related to IPR&D with no alternative future use, charged to expense. The Company did no t recognize any IPR&D expense for the years ended December 31, 2023 and 2022. Patent Costs All patent-related costs incurred in connection with filing and prosecuting patent applications such as direct application fees, and legal and consulting expenses are expensed as incurred due to the uncertainty about the recovery of the expenditure. Patent-related costs are classified as general and administrative expenses within the Company’s consolidated statements of operations and comprehensive loss. Foreign Currency Transactions The functional currency for the Company’s wholly-owned foreign subsidiary, Acrivon AB, is the United States dollar. All foreign currency transaction gains and losses are recognized in the consolidated statements of operations and comprehensive loss through other income, net. The Company recognized a net foreign currency transaction gain of $ 0.1 million during the year ended December 31, 2023, which is primarily related to unrealized and realized foreign currency gains and losses as a result of transactions entered into by Acrivon AB in currencies other than the United States dollar. The Company did no t recognize any material foreign currency transaction gain or loss during the year ended December 31, 2022. Leases Effective on January 1, 2021, the Company accounts for leases in accordance with Accounting Standards Update (“ASU”) No. 2016-02, Leases , as subsequently amended (collectively, “ASC 842”). In accordance with ASC 842, the Company determines whether an arrangement is or contains a lease at inception. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date, when control of the underlying asset is transferred from the lessor to the lessee, as operating or finance leases and records a ROU asset and a lease liability on the consolidated balance sheets for all leases with an initial lease term of greater than 12 months. The Company has elected to not recognize leases with a lease term of 12 months or less, but payments are recognized as expense on a straight-line basis over the lease term. The Company enters into contracts that contain both lease and non-lease components. Non-lease components may include maintenance, utilities, and other operating costs. For leases of real estate, the Company combines the lease and associated non-lease components in its lease arrangements as a single lease component. Variable costs, such as utilities or maintenance costs, are not included in the measurement of right-of-use assets and lease liabilities, but rather are expensed when the event determining the amount of variable consideration to be paid occurs. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease if readily determinable. If the rate implicit is not readily determinable, the Company utilizes its incremental borrowing rate, which reflects the fixed rate at which the Company could borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. ROU assets are further adjusted for initial direct costs, prepaid rent, or incentives received. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as interest expense using the effective interest method and (ii) a portion that reduces the finance liability associated with the lease. In addition, the Company examines other contracts with suppliers, vendors and outside parties to identify whether such contracts contain an embedded lease and, as applicable, records such embedded leases in accordance with ASC 842. Stock-Based Compensation The Company accounts for all stock-based payment awards granted to employees and non-employees as stock-based compensation expense at fair value, based on the date of the grant, and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective award. The Company’s stock-based payments include stock options and grants of common stock. The measurement date for employee awards is the date of grant, and stock-based compensation costs are recognized as expense over the employees’ requisite service period, which is the vesting period, on a straight-line basis. The Company adopted ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU No. 2018-07”) at inception of the 2019 Stock Incentive Plan, prior to the issuance of any stock option grants. The measurement date for non-employee awards is the date of grant, and stock-based compensation costs for non-employees are recognized as expense over the vesting period on a straight-line basis. The Company accounts for forfeitures as they occur. Stock-based compensation expense is classified in the accompanying consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipients service payments are classified. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model, which requires inputs based on certain subjective assumptions. Prior to the IPO, the Company’s board of directors (“Board”) determined the fair value of the Company’s common stock, taking into consideration its most recently available third-party valuations of common stock as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the grant date. The Company has historically been a private company and lacks company-specific historical and implied volatility information. Following the IPO, the fair value of the Company's common stock is determined based on the quoted market price of common stock. The Company estimates its expected stock volatility based on the historical volatility of a publicly traded set of representative companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends on common stock and does not expect to pay any cash dividends in the foreseeable future. Net Loss per Share Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. Net loss per share attributable to common stockholders is calculated using the two-class method, which is an earnings allocation formula that determines net loss per share for the holders of the Company’s common shares and participating securities. The Company’s convertible preferred stock contained participation rights in any dividend paid by the Company and was deemed to be a participating security. Net loss attributable to common stockholders and participating preferred shares, if any, are allocated to each share on an as-converted basis as if all of the earnings for the period had been distributed. The participating securities did not include a contractual obligation to share in losses of the Company and are not included in the calculation of net loss per share in the periods in which a net loss is recorded. Diluted net loss per share is computed using the more dilutive of (a) the two-class method or (b) the if-converted method. The Company allocates earnings first to preferred stockholders based on dividend rights and then to common and preferred stockholders based on ownership interests. The weighted-average number of common shares included in the computation of diluted net loss per share gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and preferred stock. Common stock equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders since dilutive common shares are not assumed to have been issued if their effect is antidilutive. The Company reported a net loss attributable to common stockholders for the years ended December 31, 2023 and 2022. Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or the Company’s tax returns. Under this method, deferred tax assets and liabilities are determined based on the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established. The Company accounts for uncertain tax positions recognized in the consolidated financial statements by prescribing a “more likely than not” threshold for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. There are no unrecognized tax benefits included in the Company’s consolidated balance sheets as of December 31, 2023 and 2022. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company has not recognized interest or penalties in its consolidated statements of operations and comprehensive loss since inception. Recently Adopted Accounting Pronouncements ASU 2016-13, Financial Instruments–Credit Losses In June 2016, the FASB issued ASU 2016-13, Financial Instruments–Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ ASU 2016-13 ”), and also issued subsequent amendments to the initial guidance: ASU 2018-19, ASU 2019-04, ASU 2019-05, ASU 2020-02 and ASU 2020-03 (collectively, “Topic 326”). Topic 326 significantly changes the impairment model for most financial assets and certain other instruments. Topic 326 requires immediate recognition of estimated credit losses expected to occur over the remaining life of many financial assets, which will generally result in earlier recognition of allowances for credit losses on loans and other financial instruments. The measurement is based on relevant information, including historical experience, current conditions and reasonable and supportable forecasts that affect the collectability of the reported amount and requires disclosure requirements related to credit risks. The Company adopted this accounting standard as of January 1, 2023 , with no material impact on its consolidated financial statements and related disclosures. Recently Issued Accounting Pronouncements Not Yet Adopted ASU 2023-06, Disclosure Improvements In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. The amendments clarify or improve disclosure and presentation requirements on various disclosure areas, including the statement of cash flows, earnings per share, debt, equity, and derivatives. The amendments will align the requirements in the FASB ASC with the SEC’s regulations. The amendments in this ASU will be effective on the date the related disclosures are removed from Regulation S-X or Regulation S-K by the SEC, and will not be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. Early adoption is prohibited. As the Company is currently subject to these SEC requirements, ASU 2023-06 is not expected to have a significant impact on the Company. ASU 2023-07, Segment Reporting (Topic 280) In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which requires public entities to disclose information about their reportable segments’ significant expenses on an interim and annual basis. All disclosure requirements under ASU 2023-07 are also required for public entities with a single reportable segment. The ASU is effective for annual periods beginning after December 15, 2024 and for interim periods within fiscal years beginning after December 15, 2025. Early adoption is permitted. The Company is currently evaluating the effect of this update on its consolidated financial statements and related disclosures. ASU 2023-09, Income Taxes (Topic 740) In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures , which requires disclosure of disaggregated income taxes paid, prescribes standard categories for the components of the effective tax rate reconciliation, and modifies other income tax-related disclosures. The ASU is effective for annual periods beginning after December 15, 2024 and allows for adoption on a prospective basis, with a retrospective option. The Company is currently evaluating the effect of this update on its consolidated financial statements and related disclosures.

Investments

Investments	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Investments	3. Investments The following table summarizes the amortized cost and estimated fair value of the Company's U.S. Treasury securities and U.S. government-sponsored enterprise securities, which are considered to be available-for-sale investments and were included in short-term investments as of December 31, 2023 and in short and long-term investments as of December 31, 2022 (in thousands): December 31, 2023 Amortized Cost Gross Unrealized Gross Unrealized Fair Value Short-term investments: U.S. Treasury securities $ 41,470 $ 22 $ ( 19 ) $ 41,473 U.S. government-sponsored enterprise securities 50,056 — ( 86 ) 49,970 $ 91,526 $ 22 $ ( 105 ) $ 91,443 December 31, 2022 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Short-term investments: U.S. Treasury securities $ 32,174 $ 3 $ ( 34 ) $ 32,143 U.S. government-sponsored enterprise securities 66,106 68 ( 85 ) 66,089 Long-term investments: U.S. Treasury securities 7,242 — ( 4 ) 7,238 U.S. government-sponsored enterprise securities 34,686 — ( 43 ) 34,643 $ 140,208 $ 71 $ ( 166 ) $ 140,113 Certain short-term debt securities with original maturities of less than 90 days are included in cash and cash equivalents on the consolidated balance sheets and are not included in the tables above. As of December 31, 2023 and 2022, all short-term investments had contractual maturities within one year . As of December 31, 2022, all long-term investments had contractual maturities between one to two years . The aggregate fair value of available-for-sale securities held by the Company in an unrealized loss position for less than 12 months as of December 31, 2023 was $ 59.9 million. The unrealized losses on the Company’s investments of $ 0.1 million and $ 0.2 million as of December 31, 2023 and 2022, respectively, were caused by interest rate increases which resulted in the decrease in market value of these securities. There were no available-for-sale securities in a continuous unrealized loss position for greater than 12 months. Because the decline in fair value is attributable to changes in interest rates and not credit quality, and because the Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases, which may be maturity, there are no allowances for credit losses as of December 31, 2023.

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurement	4. Fair Value Measurement The following tables present information about the Company’s financial assets measured at fair value on a recurring basis (in thousands): Fair Value Measurements at December 31, 2023 Using: Assets: Total Level 1 Level 2 Level 3 Cash equivalents: Money market funds $ 31,191 $ 31,191 $ — $ — Short-term investments: U.S. Treasury securities 41,473 41,473 — — U.S. government-sponsored enterprise securities 49,970 — 49,970 — Total assets $ 122,634 $ 72,664 $ 49,970 $ — Fair Value Measurements at December 31, 2022 Using: Assets: Total Level 1 Level 2 Level 3 Cash equivalents: Money market funds $ 24,082 $ 24,082 $ — $ — Short-term investments: U.S. Treasury securities 32,143 32,143 — — U.S. government-sponsored enterprise securities 66,089 — 66,089 — Long-term investments: U.S. Treasury securities 7,238 7,238 — — U.S. government-sponsored enterprise securities 34,643 — 34,643 — Total assets $ 164,195 $ 63,463 $ 100,732 $ — The Company classifies its money market funds and U.S. Treasury securities as Level 1 assets under the fair value hierarchy as these assets have been valued using quoted market prices in active markets without any valuation adjustment. The Company classifies its U.S. government-sponsored enterprise securities as Level 2 assets under the fair value hierarchy as these assets have been valued using information obtained through a third-party pricing service as of the balance sheet date, using observable market inputs that may include trade information, broker or dealer quotes, bids, offers, or a combination of these data sources. During the years ended December 31, 2023 and 2022, there were no transfers between levels. The Company uses the carrying amounts of its restricted cash, prepaid expenses and other current assets, accounts payable and accrued expenses to approximate their fair values due to the short-term nature of these amounts.

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	5. Property and Equipment, net Property and equipment, net consisted of the following (in thousands): December 31, 2023 2022 Laboratory and computer equipment $ 2,955 $ 2,340 Furniture and fixtures 172 172 Construction in progress 1,308 — Total property and equipment 4,435 2,512 Less: accumulated depreciation ( 956 ) ( 420 ) Property and equipment, net $ 3,479 $ 2,092 Depreciation expense related to property and equipment for the years ended December 31, 2023 and 2022 was $ 0.5 million and $ 0.4 million, respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	6. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, 2023 2022 Accrued compensation and benefits $ 3,860 $ 2,662 Accrued research and development expenses 2,661 790 Accrued legal, accounting and other professional fees 667 648 Accrued other 190 44 Accrued offering costs — 673 Deferred sublease income — 69 Total accrued expenses and other current liabilities $ 7,378 $ 4,886

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leases	7. Leases In September 2020, the Company entered into an operating lease agreement, denominated in Swedish Krona, for office and laboratory space located in Lund, Sweden. The term of the lease commenced in October 2020 and expired in September 2023 , with an option to extend the term for an additional three years . In September 2023, the Company modified the lease agreement. The modification extended the lease term for an additional quarter, resulting in a de minimis impact to the ROU asset and corresponding lease liability. In December 2020, the Company entered into a lease agreement for laboratory and office space located at 480 Arsenal Way, Watertown, Massachusetts (the “Arsenal Way Lease”). The term of the lease commenced in April 2021 . The lease has an initial term from the rent commencement date, which is a month after the lease commencement date, of approximately seven years , with an option to extend the term for an additional five years at then-market rental rates. In connection with the execution of the lease agreement, the Company delivered a letter of credit of $ 0.3 million to the landlord, which is included in restricted cash in the accompanying consolidated balance sheets. The landlord contributed an aggregate of $ 0.7 million toward the cost of tenant improvements for the premises. Under the terms of the lease, the base rent is $ 1.0 million, subject to a 3 % annual rent increase, plus an allocation of operating expenses and taxes. In May 2021, the Company entered into an agreement to sublease 6,330 rentable square feet of its Arsenal Way Lease to a subtenant through March 2023 . Sublease income was recognized on a straight-line basis over the term of the sublease agreement. Sublease rent income, including common area maintenance charges, was $ 0.2 million and $ 0.8 million for the years ended December 31, 2023 and 2022, respectively, which was allocated and recorded as a reduction to general and administrative expenses and research and development expenses. The Company was not relieved of its primary obligation under the Arsenal Way Lease as a result of the sublease. In August 2023, the Company entered into an operating lease agreement, denominated is Swedish Krona, for office and laboratory space located in Lund, Sweden. The term of the lease commenced in December 2023 . The lease has an initial term of three years , with an option to extend the term for an additional three years . Lease payments are made on a quarterly basis. The Company recognizes monthly operating lease expense on a straight-line basis over the term of the lease as research and development or general and administrative expenses in the consolidated statements of operations and comprehensive loss. Variable lease expense relates primarily to office lease common area maintenance, insurance, and property taxes, is expensed as incurred, and is excluded from the calculation of the lease liabilities and right-of-use-assets. The following table summarizes the presentation of the Company’s operating leases on its consolidated balance sheets (in thousands): Leases Balance sheet classification December 31, 2023 December 31, 2022 Assets: Operating lease assets Operating lease right-of-use assets $ 4,429 $ 4,770 Total lease assets $ 4,429 $ 4,770 Liabilities: Current: Operating lease liabilities Operating lease liability, current $ 877 $ 726 Noncurrent: Operating lease liabilities Operating lease liability, long-term 3,767 4,235 Total lease liabilities $ 4,644 $ 4,961 The components of lease cost under ASC 842 included within research and development expenses and general and administrative expenses in the Company’s consolidated statements of operations and comprehensive loss were as follows (in thousands): For the Year Ended December 31, Lease cost 2023 2022 Operating lease cost $ 1,140 $ 1,143 Variable lease cost 492 519 Sublease income ( 134 ) ( 537 ) Total lease cost $ 1,498 $ 1,125 As of December 31, 2023 and 2022, the weighted-average remaining lease term for operating leases was 4.2 years and 5.3 years, respectively, and the weighted-average discount rate was 8.30 % and 7.86 %, respectively. Cash paid for amounts included in the measurement of lease liabilities was $ 1.1 million for each of the years ended December 31, 2023 and 2022. Future minimum annual lease commitments under the Company’s non-cancelable operating leases as of December 31, 2023 were as follows (in thousands): Year ended December 31, Amount 2024 $ 1,221 2025 1,315 2026 1,349 2027 1,200 2028 404 Total lease payments 5,489 Less: interest ( 845 ) Present value of operating lease liabilities $ 4,644

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Class of Stock Disclosures [Abstract]
Stockholders' Equity	8. Stockholders' Equity Prior to the IPO, the voting, dividend and liquidation rights of the holders of the Company’s common stock were subject to and qualified by the rights, powers and preferences of the holders of the Preferred Stock as set forth above and described in the Company’s final prospectus for the IPO filed with the SEC pursuant to Rule 424(b)(4) under the Securities Act on November 16, 2022. In October 2022, the Board approved the amended and restated certificate of incorporation, which was filed upon the closing of the IPO and which authorized the Company to issue up to 10,000,000 shares of preferred stock, with a par value of $ 0.001 . There are no shares of preferred stock issued or outstanding as of December 31, 2023. As of December 31, 2023 and 2022, the Company’s Amended and Restated Certificate of Incorporation authorized the Company to issue 500,000,000 shares of common stock, with a par value of $ 0.001 . The holders of the common stock are entitled to one vote for each share of common stock held at all meetings of stockholders (and written actions in lieu of meetings), and there are not any cumulative voting rights. The number of authorized shares of common stock may be increased or decreased by the affirmative vote of the holders of shares of capital stock of the Company; however, the issuance of common stock may be subject to the vote of the holders of one or more series of preferred stock that may be required by terms of the Amended and Restated Certificate of Incorporation. As of December 31, 2023 and 2022, the Company had reserved the following shares of common stock for the potential exercise of stock options, vesting of restricted stock units, as well as the remaining shares available for issuance under the 2022 Stock Option Incentive Plan (the “2022 Plan”), the 2022 Employee Stock Purchase Plan (the “2022 ESPP”), and the 2023 Inducement Plan (the “Inducement Plan”): December 31, 2023 2022 Options to purchase common stock 3,117,042 3,300,935 Unvested restricted stock units 1,759,918 1,787,152 Remaining shares reserved for future issuance 2,107,745 733,636 Total 6,984,705 5,821,723

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	9. Stock-Based Compensation 2022 Equity Incentive Plan In October 2022, the Board adopted, and in November 2022 its stockholders approved, the 2022 Plan, which replaced the 2019 Plan and became effective immediately prior to and contingent upon the execution of the underwriting agreement related to the Company’s IPO. No further shares were issued under the 2019 Plan as of the effective date of the 2022 Plan. The 2022 Plan allows the Company to make equity-based and cash-based incentive awards to its officers, employees, directors, and consultants. The 2022 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock awards, restricted stock units (“RSUs”) and other stock-based awards. The number of shares initially reserved for issuance under the 2022 Plan was 5,606,723 , which is the sum of: (i) 2,555,271 new shares, plus (ii) the number of shares that remained available for issuance under the 2019 Plan at the time the 2022 Plan became effective and (iii) up to 2,148,679 shares of common stock subject to awards granted under the 2019 Plan that, after the effective date of the 2022 Plan, expire or otherwise terminate without having been exercised in full or are forfeited to or repurchased. In addition, the number of shares reserved and available for issuance under the 2022 Plan shall automatically increase beginning on January 1, 2023 and each January 1 thereafter, by five percent of the aggregate number of shares of common stock of all classes issued and outstanding on the immediately preceding December 31 or such lesser number of shares of common stock as determined by the compensation committee. The shares of common stock underlying any awards under the 2022 Plan and the 2019 Plan that are forfeited, canceled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, reacquired by the Company prior to vesting, satisfied without the issuance of stock, expire, or are otherwise terminated (other than by exercise) will be added back to the shares of common stock available for issuance under the 2022 Plan. As of December 31, 2023, there were 1,369,341 shares reserved for future issuance under the 2022 Plan. 2022 Employee Stock Purchase Plan In October 2022, the Board adopted, and in November 2022 its stockholders approved, the 2022 ESPP, which became effective immediately prior to and contingent upon the execution of the underwriting agreement related to the Company’s IPO. A total of 215,000 shares of common stock were initially reserved for issuance under this plan. The number of shares of common stock that may be issued under the 2022 ESPP shall cumulatively increase beginning on January 1, 2023 and each January 1 thereafter through January 1, 2032, by one percent of the outstanding number of shares of common stock on the immediately preceding December 31 or such lesser number of shares as determined by the compensation committee. No shares of the Company's common stock have been issued and no stock-based compensation expense has been recognized related to the 2022 ESPP. As of December 31, 2023, there were 434,204 shares reserved for future issuance under the 2022 ESPP. 2023 Inducement Plan In June 2023, the Board adopted the Inducement Plan to facilitate the granting of equity awards as an inducement material to new employees joining the Company. The Inducement Plan is administered by the compensation committee of the Board. The Board initially reserved 450,000 common shares of the Company for issuance under the Inducement Plan. The only persons eligible to receive awards under the Inducement Plan are individuals who are new employees and satisfy the standards for inducement grants under Nasdaq Listing Rule 5635(c)(4) or 5635(c)(3), as applicable. The terms of the Inducement Plan are identical to the terms of the 2022 Plan, except that no incentive stock options shall be awarded under the Inducement Plan. As of December 31, 2023, there were 304,200 shares reserved for future issuance under the Inducement Plan. Stock Options The Company has granted stock options with service-based vesting conditions. Stock options typically vest over four years and have a maximum term of ten years . The Company typically grants stock options to employees and non-employees at exercise prices deemed by the Board to be equal to the fair value of the common stock at the time of grant. The assumptions that the Company used in the Black-Scholes option-pricing model to determine the grant date fair value of stock options granted were as follows: December 31, 2023 2022 Risk-free interest rate range 3.40 % - 4.84 % 2.69 % - 4.15 % Dividend yield 0.00 % 0.00 % Expected life of options (years) 5.8 - 6.1 5.8 - 6.1 Volatility rate range 81.63 % - 83.55 % 71.06 % - 82.54 % Fair value of common stock range $ 3.89 - $ 20.50 $ 3.63 - $ 12.50 The following table summarizes the Company’s stock option activity: Number Weighted-Average Weighted-Average Aggregate Intrinsic Outstanding as of December 31, 2022 3,300,935 $ 6.29 9.26 $ 18,346 Granted 297,556 10.43 Exercised ( 292,444 ) 2.65 Forfeited or canceled ( 189,005 ) 6.12 Outstanding as of December 31, 2023 3,117,042 $ 7.04 8.34 $ 3,409 Vested and expected to vest as of December 31, 2023 3,117,042 $ 7.04 8.34 $ 3,409 Vested and exercisable as of December 31, 2023 1,313,352 $ 5.08 7.86 $ 2,342 Included in the table above are 123,825 options outstanding as of December 31, 2023 that were granted under the Inducement Plan. The aggregate intrinsic value of options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the common stock as of the end of the reporting period. The aggregate intrinsic value of options exercised during the years ended December 31, 2023 and 2022 was $ 2.1 million and $ 0.1 million, respectively. The weighted-average grant date fair value of the Company’s stock options granted during the years ended December 31, 2023 and 2022 was $ 7.59 and $ 5.52 per option, respectively. As of December 31, 2023, there was $ 10.5 million of unrecognized stock-based compensation expense related to stock option grants. The Company expects to recognize this amount over a weighted-average period of 2.5 years. The total fair value of options vested during the years ended December 31, 2023 and 2022, was $ 4.2 million and $ 0.5 million, respectively. RSUs The Company has granted RSUs with service vesting based conditions. Unvested shares of restricted common stock may not be sold or transferred by the holder. They are legally issued and outstanding. These restrictions lapse according to the time-based vesting of each award. A summary of the RSU activity during the year ended December 31, 2023 is as follows: Restricted Stock Units Weighted-Average Unvested at December 31, 2022 1,787,152 $ 12.49 Granted 563,060 $ 11.20 Vested ( 566,260 ) $ 12.52 Forfeited ( 24,034 ) $ 10.86 Unvested at December 31, 2023 1,759,918 $ 12.09 Included in the table above are 21,975 unvested RSUs as of December 31, 2023 that were granted under the Inducement Plan. RSUs typically vest over four years . If and when an RSU vests, the Company will issue one share of common stock for each whole RSU that has vested, subject to satisfaction of the employee's tax withholding obligations. Upon vesting and settlement of RSUs, the Company may withhold the portion of those shares with a fair market value equal to the amount of the minimum statutory withholding taxes due. The withheld shares are accounted for as repurchases of common stock. The weighted-average grant date fair value of the Company’s RSUs granted during the years ended December 31, 2023 and 2022 was $ 11.20 and $ 12.49 per RSU, respectively. As of December 31, 2023, there was $ 19.6 million of unrecognized stock-based compensation expense related to RSUs. The Company expects to recognize this amount over a weighted-average period of 2.3 years. The total fair value of RSUs vested during the year ended December 31, 2023 was $ 7.1 million. No RSUs vested in 2022. Stock-Based Compensation Expense Stock-based compensation expense included in the Company’s consolidated statements of operations and comprehensive loss is as follows (in thousands): Year Ended December 31, 2023 2022 General and administrative $ 9,089 $ 1,396 Research and development 2,529 789 Total stock-based compensation expense $ 11,618 $ 2,185

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes The effective income tax rate differed from the amount computed by applying the federal statutory rate to the Company’s loss before income taxes as follows: December 31, 2023 2022 Tax effected at statutory rate 21.0 % 21.0 % State taxes 6.0 % 7.0 % Stock-based compensation ( 1.3 %) ( 0.5 %) Executive compensation ( 1.7 %) ( 0.7 %) Federal research and development credits 4.4 % 1.3 % Change in valuation allowance ( 28.5 %) ( 28.1 %) Total ( 0.1 %) — % The Company's total deferred tax assets at December 31, 2023 and 2022 are as follows (in thousands): December 31, 2023 2022 Deferred Tax Assets Net operating loss carryforward $ 9,395 $ 6,137 R&D credit carryovers 3,985 1,015 Section 174 R&D amortization 13,819 5,093 Operating lease liabilities 1,134 1,309 Accrued expenses and other current liabilities 919 528 Capitalized licenses 3,482 2,039 Other 554 226 33,288 16,347 Valuation allowance ( 31,761 ) ( 14,562 ) Deferred tax asset 1,527 1,785 Deferred Tax Liabilities Property and equipment ( 457 ) ( 531 ) Operating lease right-of-use assets ( 1,070 ) ( 1,254 ) Deferred tax liability ( 1,527 ) ( 1,785 ) Net deferred tax asset $ — $ — The Company has had no income tax expense due to operating losses incurred since inception. ASC 740, Income Taxes , requires a valuation allowance to reduce the deferred tax assets reported if, based on the weight of the evidence, it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets. Based on this, the Company has provided a valuation allowance for the full amount of the net deferred tax assets as the realization of the deferred tax assets is not determined to be more likely than not. During 2023, the valuation allowance increased by $ 17.2 million primarily due to the increase in the Company's book loss reported in the period and the generation of additional research and development credits. As of December 31, 2023, the Company had $ 33.0 million and $ 35.3 million of federal and state operating loss carryforwards (“NOLs”), respectively. The federal NOLs are not subject to expiration and the state NOLs begin to expire in 2038 . These loss carryforwards are available to reduce future federal taxable income, if any. As of December 31, 2023, the Company also has federal and state research and development tax credit carryforwards of approximately $ 3.1 million and $ 1.2 million, respectively, to offset future income taxes, which will begin to expire beginning in December 2033. These loss carryforwards are subject to review and possible adjustment by the appropriate taxing authorities. The amount of loss carryforwards that may be utilized in any future period may be limited based upon changes in the ownership of the Company's ultimate parent. The 2017 Tax Cuts and Jobs Act (“TCJA”) included a multitude of tax provisions, including several deferred changes that became effective for tax years ending after December 31, 2021. Included in the provisions was the TCJA’s amendment to Section 174, which now requires U.S.-based and non-U.S-based research and experimental (“R&E”) expenditures to be capitalized and amortized over a period of five or 15 years , respectively, for amounts paid in tax years starting after December 31, 2021. Prior to the TCJA amendment, Section 174 allowed taxpayers to either immediately deduct R&E expenditures in the year paid or incurred. The Company has applied this required change in accounting method beginning in 2022. On December 18, 2015, the Protecting Americans from Tax Hikes (“PATH”) Act of 2015 was signed into law. The PATH Act has created several R&D credit provisions, including allowing qualified small business to utilize the research credit against the employer portion of payroll tax (i.e., FICA tax) not exceeding $ 500,000 per year. The Company does not qualify as a small business for 2023 due to gross receipts exceeding $ 5.0 million. The Company follows the provisions of ASC 740-10, Accounting for Uncertainty in Income Taxes , which specifies how tax benefits for uncertain tax positions are to be recognized, measured, and recorded in financial statements; requires certain disclosures of uncertain tax matters; specifies how reserves for uncertain tax positions should be classified on the consolidated balance sheets; and provides transition and interim period guidance, among other provisions. As of December 31, 2023 and 2022, the Company has no t recorded tax reserves associated with any unrecognized tax benefits. The Company’s policy is to recognize interest and penalties accrued on any uncertain tax positions as a component of income tax expense, if any, in its consolidated statements of operations and comprehensive loss. As of December 31, 2023, and 2022, the Company had no reserves for uncertain tax positions. For the years ended December 31, 2023 and 2022, no estimated interest or penalties were recognized on uncertain tax positions. The Company has not conducted a study of its research and development credit carryforwards. This study may result in an adjustment to research and development credit carryforwards; however, until a study is completed, and any adjustment is known, no amounts are being presented as an uncertain tax position. A full valuation allowance has been provided against the Company’s research and development credits and, if an adjustment is required, this adjustment would be offset by an adjustment to the valuation allowance. Thus, there would be no impact to the consolidated balance sheets or consolidated statements of operations and comprehensive loss if an adjustment were required. The Company's federal and Massachusetts income tax returns for the years ended December 31, 2020 to December 31, 2023 remain open and are subject to examination by the Internal Revenue Service and state taxing authorities. In addition, the Company’s tax carryover attributes such as net operating losses or credits from earlier periods are also subject to examination.

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Net Loss Per Share	11. Net Loss Per Share Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share amounts): December 31, 2023 2022 Numerator: Net loss attributable to common stockholders—basic and diluted $ ( 60,388 ) $ ( 31,167 ) Denominator: Weighted-average common stock outstanding—basic and diluted 22,078,190 4,121,912 Net loss per share—basic and diluted $ ( 2.74 ) $ ( 7.56 ) The Company’s potentially dilutive securities, which include stock options and RSUs, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following shares from the computation of diluted net loss per share attributable to common stockholders as of December 31, 2023 and 2022 because including them would have had an anti-dilutive effect: December 31, 2023 2022 Options to purchase common stock 3,117,042 3,300,935 Unvested restricted stock units 1,759,918 1,787,152

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Leases The Company’s commitments under its operating leases are described in Note 7. License Agreement In January 2021, the Company entered into a license agreement and stock issuance agreement with Eli Lilly and Company (“Lilly”) (collectively, the “Lilly Agreement”), pursuant to which the Company has been granted an exclusive, royalty-bearing sublicensable license to certain patents owned or controlled by Lilly, to commercially develop, manufacture, use, distribute and sell therapeutic products containing the compound prexasertib. The license from Lilly comprises three families of patent filings all relating to ACR-368. Additionally, pursuant to the Lilly Agreement, the Company received ACR-368 drug substance and drug product to be used in future research. As initial consideration for the license, the Company made a one-time, non-creditable, non-refundable upfront payment of $ 5.0 million. As additional consideration for the license, the Company is required to pay Lilly aggregate development and commercial milestone payments of up to $ 168.0 million, of which $ 5.0 million is due prior to a new drug application. The Company is also obligated to pay a tiered percentage royalty on annual net sales ranging from single-digit up to a maximum of 10 %, subject to certain specified reductions. Royalties are payable by the Company on a licensed product-by-licensed product and country-by-country basis until the later of the expiration of the last valid claim covering the licensed product in such country, expiration of all applicable regulatory exclusivities in such country for such licensed product and the tenth anniversary of the first commercial sale of such licensed product in such country, provided, that the Company’s obligation to pay royalties for a given licensed product in a given country will expire earlier upon achievement of certain sales thresholds by generic products in such country. As of December 31, 2023, no milestone payments or royalties have been incurred related to the Lilly Agreement. Companion Diagnostic Agreement In June 2022, the Company entered into a companion diagnostic agreement (the “Akoya Agreement”) with Akoya Biosciences, Inc. (“Akoya”), pursuant to which the Company has engaged Akoya to co-develop, validate, and commercialize the Company’s proprietary ACR-368 OncoSignature test, the companion diagnostic that will be used to identify patients with cancer most likely to respond to ACR-368. Subject to the terms of the Akoya Agreement, as subsequently amended, the Company paid Akoya a one-time, non-refundable, non-creditable upfront payment in the amount of $ 0.6 million. The Company is obligated to pay Akoya up to an aggregate of $ 17.3 million upon the achievement of specified development milestones. Through December 31, 2023, the Company has made aggregate payments of $ 7.0 million to Akoya. During the years ended December 31, 2023 and 2022, the Company recorded research and development expenses of $ 6.0 million and $ 2.3 million, respectively. $ 1.3 million was due to Akoya and included in accounts payable as of December 31, 2023. Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with each of its directors and executive officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or services as directors or executive officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not currently aware of any indemnification claims and had not accrued any liabilities related to such obligations in its consolidated financial statements as of December 31, 2023 and 2022. Legal Proceedings From time to time, in the ordinary course of business, the Company is subject to litigation and regulatory examinations as well as information gathering requests, inquiries and investigations. We are not currently party to any material legal proceedings and are not aware of any pending or threatened legal proceedings against us that we believe could have an adverse effect on our business, operating results or financial condition. Other Contracts The Company enters into contracts in the normal course of business with various third parties for preclinical research studies, clinical trials, testing, manufacturing and other services. These contracts generally provide for termination upon notice and are cancelable without significant penalty or payment, and do not contain any minimum purchase commitments.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Employee Benefit Plans	13. Employee Benefit Plans Effective January 1, 2019, the Company adopted a 401(k) Plan for its employees, which is designed to be qualified under Section 401(k) of the Internal Revenue Code. Eligible employees are permitted to contribute to the 401(k) Plan within statutory and 401(k) Plan limits. Since inception of the 401(k) Plan and through the year ended December 31, 2023, the Company has not made any contributions to the 401(k) Plan.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include the operations of Acrivon Therapeutics, Inc. and its wholly-owned subsidiaries. All intercompany accounts, transactions and balances have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the accrual of research and development expenses and the valuation of stock-based awards. The Company bases its estimates on historical experience when available, known trends and other market specific data, or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates when there are changes in circumstances, facts and experience. Changes in estimates and assumptions are reflected in reported results in the period in which they become known. Actual results could differ from those estimates.
Segment Information	Segment Information Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one operating segment. The Company’s focus is the research and development of precision oncology therapies. The Company’s chief operating decision maker, its chief executive officer, manages the Company’s operations on a consolidated basis for the purpose of allocating resources. As the Company has one reportable segment, all required segment financial information is presented in the consolidated financial statements. As of December 31, 2023, $ 5.7 million and $ 2.2 million of the Company’s long-lived assets are held in the United States and in Sweden, respectively.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments purchased with original maturities of 90 days or less at acquisition to be cash equivalents. Cash and cash equivalents include standard checking accounts and amounts held in money market funds. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits.
Restricted Cash	Restricted Cash Cash accounts with any type of restriction are classified as restricted cash. The Company has restricted cash deposits with a bank, which serve as collateral for a letter of credit issued to the landlord of the Company’s leased facility for a security deposit. The Company classified this amount as restricted cash in the accompanying consolidated balance sheets within non-current assets based on the release date of restrictions.
Deferred Offering Costs	Deferred Offering Costs The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of an equity financing, these costs are recorded as a reduction of the proceeds from the offering in stockholders’ equity as a reduction of additional paid-in capital generated as a result of the offering. Should the Company choose to not initiate such financing, the deferred offering costs would be immediately expensed as operating expenses. Deferred offering costs associated with the ATM Program are reclassified to additional paid-in-capital on a pro-rata basis when the Company completes offerings under the ATM Program. Any remaining deferred offering costs will be expensed to the consolidated statements of operations and comprehensive loss should the planned offering be abandoned. As of December 31, 2023, $ 0.3 million of such deferred offering costs are capitalized.
Concentration of Credit Risk and Significant Suppliers	Concentration of Credit Risk and Significant Suppliers Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and investments. The Company has not experienced any credit losses on its cash, cash equivalents, or investments. The Company maintains its cash, cash equivalents and investments, which at times exceed insurance limits, at major financial institutions. The Company has not experienced any losses in such accounts and management believes that such funds are not exposed to any significant credit or concentration risk. However, the Company may face exposure, including constraint on liquidity and access to capital, if there is failure by these or other financial institutions. The Company is dependent on third-party contract research organizations (“CROs”) and contract manufacturing organizations to supply certain intellectual property and services for research activities in its drug candidates. In particular, the Company relies and expects to continue to rely on a small number of these organizations to supply it with its requirements for key raw materials related to these programs. These drug candidates could be adversely affected by a significant interruption in the supply of key raw materials. Additionally, the Company relies on a single companion diagnostic collaborator to perform ACR-368 OncoSignature tests in the Company’s clinical trials (see Note 12).
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as a change in equity of a business enterprise during a period resulting from transactions from non-owner sources. Comprehensive loss includes net loss and certain changes in stockholders' equity that are excluded from net loss. The Company had a net change in available-for-sale securities during the years ended December 31, 2023 and 2022, which met the criteria as other comprehensive loss and, therefore, the Company’s comprehensive loss includes unrealized gains (losses) on those available-for-sale securities.
Investments	Investments The Company classifies all investments with an original maturity of greater than three months and less than one year upon purchase as available-for-sale. Available-for-sale securities are recorded at fair value based upon market prices at period end, with the unrealized gains and losses reported in other comprehensive loss. The amortized cost of debt securities in this category is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization is included in interest income, presented within other income, net in the consolidated statements of operations and comprehensive loss. Realized gains and losses and declines in value due to credit-related factors on available-for-sale securities are included in other income, net in the consolidated statements of operations and comprehensive loss. The cost of securities sold is based on the specific identification method. Interest on securities classified as available-for-sale is included in interest income, presented within other income, net in the consolidated statements of operations and comprehensive loss. For the years ended December 31, 2023 and 2022, other income, net, of $ 6.7 million and $ 1.5 million, respectively, included interest income of $ 7.0 million and $ 1.5 million, respectively, offset by de minimis miscellaneous items. At each balance sheet date, the Company assesses available-for-sale debt securities in an unrealized loss position to determine whether the unrealized loss or any potential credit losses should be recognized in other income, net. The Company evaluates whether it intends to sell, or it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. The Company also evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the severity of the impairment, any changes in interest rates, changes to the underlying credit ratings and forecasted recovery, among other factors. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded in other income, net. There have been no impairment or credit losses recognized during any of the periods presented.
Fair Value Measurements	Fair Value Measurements Accounting Standards Codification (“ASC”) Topic 820, Fair Value Measurement (“ASC 820”), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company’s own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tier fair value hierarchy that distinguishes among the following: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. Level 3 —Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. 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.
Property and Equipment, net	Property and Equipment, net Property and equipment are stated at cost, less accumulated depreciation. Costs for capital assets not yet placed in service are capitalized as construction in progress and depreciated once placed in service. Costs of major additions and betterments are capitalized. Maintenance and repairs which do not improve or extend the life of the respective assets are charged to expense as incurred. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets, which range from five to seven years. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. The Company's leasehold improvements as of December 31, 2023 were de minimis. The Company had no leasehold improvements as of December 31, 2022. When an item is sold or retired, the costs and related accumulated depreciation are eliminated, and the resulting gain or loss, if any, is credited or charged to the consolidated statements of operations and comprehensive loss. Property and equipment to be disposed of are carried at fair value less costs to sell. The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life (in Years) Laboratory equipment and computer equipment 5 years Furniture and fixtures 5 - 7 years Leasehold improvements Lesser of asset useful life or lease term
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company recognizes an impairment loss in the consolidated statements of operations and comprehensive loss only if the carrying amount of a long-lived asset is not recoverable based on its undiscounted future cash flows and in such case, measures an impairment loss as the difference between the carrying amount and the fair value of the asset. The Company tests long-lived assets to be held and used, including property and equipment and operating lease right-of-use (“ROU”) assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of assets or asset groups may not be fully recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written down to their fair values. The Company has no t recognized any impairment losses during the years ended December 31, 2023 and 2022.
Research and Development Expenses	Research and Development Expenses Research and development costs include (i) employee-related expenses, including salaries, benefits, and stock-based compensation expense; (ii) external research and development expenses incurred under arrangements with third parties, such as CRO agreements and consultants; (iii) costs associated with preclinical activities; and (iv) lab supplies, lab expenses and an allocation of rent, depreciation, and infrastructure. Costs incurred in connection with research and development activities are expensed as incurred. The Company enters into various consulting, research, and other agreements with commercial firms, researchers, universities and other external parties for the provision of goods and services. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the Company’s clinical sites and vendors. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. Depending upon the timing of payments to the service providers, the Company recognizes prepaid expenses or accrued expenses related to these costs. These accrued or prepaid expenses are based on management’s estimates of the work performed under service agreements, milestones achieved, and experience with similar contracts. Milestone payments under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. The Company monitors each of these factors and adjusts estimates accordingly. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception.
Asset Acquisitions and Acquired In-Process Research and Development Expenses	Asset Acquisitions and Acquired In-Process Research and Development Expenses The Company accounts for acquisitions of assets or a group of assets that do not meet the definition of a business as asset acquisitions based on the cost to acquire the asset or group of assets, which include certain transaction costs. In an asset acquisition, the cost to acquire is allocated to the identifiable assets acquired and liabilities assumed based on their relative fair values as of the acquisition date. No goodwill is recorded in an asset acquisition. Assets that are acquired in an asset acquisition for use in research and development activities that have an alternative future use are capitalized as in-process research and development (“IPR&D”). Acquired IPR&D that has no alternative future use as of the acquisition date is recognized as research and development expense as of the acquisition date. The Company will recognize additional research and development expenses in the future if and when the Company becomes obligated to make contingent milestone payments under the terms of the agreements by which it acquired the IPR&D assets. Contingent consideration in asset acquisitions is measured and recognized when payment becomes probable and reasonably estimable. Subsequent changes in the accrued amount of contingent consideration are measured and recognized at the end of each reporting period and upon settlement as an adjustment to the cost basis of the acquired asset or group of assets, or, if related to IPR&D with no alternative future use, charged to expense. The Company did no t recognize any IPR&D expense for the years ended December 31, 2023 and 2022.
Patent Costs	Patent Costs All patent-related costs incurred in connection with filing and prosecuting patent applications such as direct application fees, and legal and consulting expenses are expensed as incurred due to the uncertainty about the recovery of the expenditure. Patent-related costs are classified as general and administrative expenses within the Company’s consolidated statements of operations and comprehensive loss.
Foreign Currency Transactions	Foreign Currency Transactions The functional currency for the Company’s wholly-owned foreign subsidiary, Acrivon AB, is the United States dollar. All foreign currency transaction gains and losses are recognized in the consolidated statements of operations and comprehensive loss through other income, net. The Company recognized a net foreign currency transaction gain of $ 0.1 million during the year ended December 31, 2023, which is primarily related to unrealized and realized foreign currency gains and losses as a result of transactions entered into by Acrivon AB in currencies other than the United States dollar. The Company did no t recognize any material foreign currency transaction gain or loss during the year ended December 31, 2022.
Leases	Leases Effective on January 1, 2021, the Company accounts for leases in accordance with Accounting Standards Update (“ASU”) No. 2016-02, Leases , as subsequently amended (collectively, “ASC 842”). In accordance with ASC 842, the Company determines whether an arrangement is or contains a lease at inception. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date, when control of the underlying asset is transferred from the lessor to the lessee, as operating or finance leases and records a ROU asset and a lease liability on the consolidated balance sheets for all leases with an initial lease term of greater than 12 months. The Company has elected to not recognize leases with a lease term of 12 months or less, but payments are recognized as expense on a straight-line basis over the lease term. The Company enters into contracts that contain both lease and non-lease components. Non-lease components may include maintenance, utilities, and other operating costs. For leases of real estate, the Company combines the lease and associated non-lease components in its lease arrangements as a single lease component. Variable costs, such as utilities or maintenance costs, are not included in the measurement of right-of-use assets and lease liabilities, but rather are expensed when the event determining the amount of variable consideration to be paid occurs. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease if readily determinable. If the rate implicit is not readily determinable, the Company utilizes its incremental borrowing rate, which reflects the fixed rate at which the Company could borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. ROU assets are further adjusted for initial direct costs, prepaid rent, or incentives received. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as interest expense using the effective interest method and (ii) a portion that reduces the finance liability associated with the lease. In addition, the Company examines other contracts with suppliers, vendors and outside parties to identify whether such contracts contain an embedded lease and, as applicable, records such embedded leases in accordance with ASC 842.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for all stock-based payment awards granted to employees and non-employees as stock-based compensation expense at fair value, based on the date of the grant, and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective award. The Company’s stock-based payments include stock options and grants of common stock. The measurement date for employee awards is the date of grant, and stock-based compensation costs are recognized as expense over the employees’ requisite service period, which is the vesting period, on a straight-line basis. The Company adopted ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU No. 2018-07”) at inception of the 2019 Stock Incentive Plan, prior to the issuance of any stock option grants. The measurement date for non-employee awards is the date of grant, and stock-based compensation costs for non-employees are recognized as expense over the vesting period on a straight-line basis. The Company accounts for forfeitures as they occur. Stock-based compensation expense is classified in the accompanying consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipients service payments are classified. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model, which requires inputs based on certain subjective assumptions. Prior to the IPO, the Company’s board of directors (“Board”) determined the fair value of the Company’s common stock, taking into consideration its most recently available third-party valuations of common stock as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the grant date. The Company has historically been a private company and lacks company-specific historical and implied volatility information. Following the IPO, the fair value of the Company's common stock is determined based on the quoted market price of common stock. The Company estimates its expected stock volatility based on the historical volatility of a publicly traded set of representative companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends on common stock and does not expect to pay any cash dividends in the foreseeable future.
Net Loss per Share	Net Loss per Share Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. Net loss per share attributable to common stockholders is calculated using the two-class method, which is an earnings allocation formula that determines net loss per share for the holders of the Company’s common shares and participating securities. The Company’s convertible preferred stock contained participation rights in any dividend paid by the Company and was deemed to be a participating security. Net loss attributable to common stockholders and participating preferred shares, if any, are allocated to each share on an as-converted basis as if all of the earnings for the period had been distributed. The participating securities did not include a contractual obligation to share in losses of the Company and are not included in the calculation of net loss per share in the periods in which a net loss is recorded. Diluted net loss per share is computed using the more dilutive of (a) the two-class method or (b) the if-converted method. The Company allocates earnings first to preferred stockholders based on dividend rights and then to common and preferred stockholders based on ownership interests. The weighted-average number of common shares included in the computation of diluted net loss per share gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and preferred stock. Common stock equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders since dilutive common shares are not assumed to have been issued if their effect is antidilutive. The Company reported a net loss attributable to common stockholders for the years ended December 31, 2023 and 2022.
Income Taxes	Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or the Company’s tax returns. Under this method, deferred tax assets and liabilities are determined based on the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established. The Company accounts for uncertain tax positions recognized in the consolidated financial statements by prescribing a “more likely than not” threshold for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. There are no unrecognized tax benefits included in the Company’s consolidated balance sheets as of December 31, 2023 and 2022. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company has not recognized interest or penalties in its consolidated statements of operations and comprehensive loss since inception.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements ASU 2016-13, Financial Instruments–Credit Losses In June 2016, the FASB issued ASU 2016-13, Financial Instruments–Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ ASU 2016-13 ”), and also issued subsequent amendments to the initial guidance: ASU 2018-19, ASU 2019-04, ASU 2019-05, ASU 2020-02 and ASU 2020-03 (collectively, “Topic 326”). Topic 326 significantly changes the impairment model for most financial assets and certain other instruments. Topic 326 requires immediate recognition of estimated credit losses expected to occur over the remaining life of many financial assets, which will generally result in earlier recognition of allowances for credit losses on loans and other financial instruments. The measurement is based on relevant information, including historical experience, current conditions and reasonable and supportable forecasts that affect the collectability of the reported amount and requires disclosure requirements related to credit risks. The Company adopted this accounting standard as of January 1, 2023 , with no material impact on its consolidated financial statements and related disclosures. Recently Issued Accounting Pronouncements Not Yet Adopted ASU 2023-06, Disclosure Improvements In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. The amendments clarify or improve disclosure and presentation requirements on various disclosure areas, including the statement of cash flows, earnings per share, debt, equity, and derivatives. The amendments will align the requirements in the FASB ASC with the SEC’s regulations. The amendments in this ASU will be effective on the date the related disclosures are removed from Regulation S-X or Regulation S-K by the SEC, and will not be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. Early adoption is prohibited. As the Company is currently subject to these SEC requirements, ASU 2023-06 is not expected to have a significant impact on the Company. ASU 2023-07, Segment Reporting (Topic 280) In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which requires public entities to disclose information about their reportable segments’ significant expenses on an interim and annual basis. All disclosure requirements under ASU 2023-07 are also required for public entities with a single reportable segment. The ASU is effective for annual periods beginning after December 15, 2024 and for interim periods within fiscal years beginning after December 15, 2025. Early adoption is permitted. The Company is currently evaluating the effect of this update on its consolidated financial statements and related disclosures. ASU 2023-09, Income Taxes (Topic 740) In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures , which requires disclosure of disaggregated income taxes paid, prescribes standard categories for the components of the effective tax rate reconciliation, and modifies other income tax-related disclosures. The ASU is effective for annual periods beginning after December 15, 2024 and allows for adoption on a prospective basis, with a retrospective option. The Company is currently evaluating the effect of this update on its consolidated financial statements and related disclosures.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Schedule of Estimated Useful Lives of Property and Equipment	The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life (in Years) Laboratory equipment and computer equipment 5 years Furniture and fixtures 5 - 7 years Leasehold improvements Lesser of asset useful life or lease term

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Summary of Amortized Cost and Estimated Fair Value of Investments	The following table summarizes the amortized cost and estimated fair value of the Company's U.S. Treasury securities and U.S. government-sponsored enterprise securities, which are considered to be available-for-sale investments and were included in short-term investments as of December 31, 2023 and in short and long-term investments as of December 31, 2022 (in thousands): December 31, 2023 Amortized Cost Gross Unrealized Gross Unrealized Fair Value Short-term investments: U.S. Treasury securities $ 41,470 $ 22 $ ( 19 ) $ 41,473 U.S. government-sponsored enterprise securities 50,056 — ( 86 ) 49,970 $ 91,526 $ 22 $ ( 105 ) $ 91,443 December 31, 2022 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Short-term investments: U.S. Treasury securities $ 32,174 $ 3 $ ( 34 ) $ 32,143 U.S. government-sponsored enterprise securities 66,106 68 ( 85 ) 66,089 Long-term investments: U.S. Treasury securities 7,242 — ( 4 ) 7,238 U.S. government-sponsored enterprise securities 34,686 — ( 43 ) 34,643 $ 140,208 $ 71 $ ( 166 ) $ 140,113

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2023
Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present information about the Company’s financial assets measured at fair value on a recurring basis (in thousands): Fair Value Measurements at December 31, 2023 Using: Assets: Total Level 1 Level 2 Level 3 Cash equivalents: Money market funds $ 31,191 $ 31,191 $ — $ — Short-term investments: U.S. Treasury securities 41,473 41,473 — — U.S. government-sponsored enterprise securities 49,970 — 49,970 — Total assets $ 122,634 $ 72,664 $ 49,970 $ — Fair Value Measurements at December 31, 2022 Using: Assets: Total Level 1 Level 2 Level 3 Cash equivalents: Money market funds $ 24,082 $ 24,082 $ — $ — Short-term investments: U.S. Treasury securities 32,143 32,143 — — U.S. government-sponsored enterprise securities 66,089 — 66,089 — Long-term investments: U.S. Treasury securities 7,238 7,238 — — U.S. government-sponsored enterprise securities 34,643 — 34,643 — Total assets $ 164,195 $ 63,463 $ 100,732 $ —

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): December 31, 2023 2022 Laboratory and computer equipment $ 2,955 $ 2,340 Furniture and fixtures 172 172 Construction in progress 1,308 — Total property and equipment 4,435 2,512 Less: accumulated depreciation ( 956 ) ( 420 ) Property and equipment, net $ 3,479 $ 2,092

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Summary of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, 2023 2022 Accrued compensation and benefits $ 3,860 $ 2,662 Accrued research and development expenses 2,661 790 Accrued legal, accounting and other professional fees 667 648 Accrued other 190 44 Accrued offering costs — 673 Deferred sublease income — 69 Total accrued expenses and other current liabilities $ 7,378 $ 4,886

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Summary of Presentation of Operating Leases on Condensed Consolidated Balance Sheet	The following table summarizes the presentation of the Company’s operating leases on its consolidated balance sheets (in thousands): Leases Balance sheet classification December 31, 2023 December 31, 2022 Assets: Operating lease assets Operating lease right-of-use assets $ 4,429 $ 4,770 Total lease assets $ 4,429 $ 4,770 Liabilities: Current: Operating lease liabilities Operating lease liability, current $ 877 $ 726 Noncurrent: Operating lease liabilities Operating lease liability, long-term 3,767 4,235 Total lease liabilities $ 4,644 $ 4,961
Schedule of Components of Lease Cost	The components of lease cost under ASC 842 included within research and development expenses and general and administrative expenses in the Company’s consolidated statements of operations and comprehensive loss were as follows (in thousands): For the Year Ended December 31, Lease cost 2023 2022 Operating lease cost $ 1,140 $ 1,143 Variable lease cost 492 519 Sublease income ( 134 ) ( 537 ) Total lease cost $ 1,498 $ 1,125
Schedule of Future Minimum Annual Lease Commitments under Non-cancellable Operating Leases	Future minimum annual lease commitments under the Company’s non-cancelable operating leases as of December 31, 2023 were as follows (in thousands): Year ended December 31, Amount 2024 $ 1,221 2025 1,315 2026 1,349 2027 1,200 2028 404 Total lease payments 5,489 Less: interest ( 845 ) Present value of operating lease liabilities $ 4,644

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Class of Stock Disclosures [Abstract]
Schedule of Common Stock Shares Reserved for the Potential Conversion of Outstanding Preferred Stock and Exercise of Stock Options	As of December 31, 2023 and 2022, the Company had reserved the following shares of common stock for the potential exercise of stock options, vesting of restricted stock units, as well as the remaining shares available for issuance under the 2022 Stock Option Incentive Plan (the “2022 Plan”), the 2022 Employee Stock Purchase Plan (the “2022 ESPP”), and the 2023 Inducement Plan (the “Inducement Plan”): December 31, 2023 2022 Options to purchase common stock 3,117,042 3,300,935 Unvested restricted stock units 1,759,918 1,787,152 Remaining shares reserved for future issuance 2,107,745 733,636 Total 6,984,705 5,821,723

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Assumptions of Grant Date Fair Value of Stock Options Granted	The assumptions that the Company used in the Black-Scholes option-pricing model to determine the grant date fair value of stock options granted were as follows: December 31, 2023 2022 Risk-free interest rate range 3.40 % - 4.84 % 2.69 % - 4.15 % Dividend yield 0.00 % 0.00 % Expected life of options (years) 5.8 - 6.1 5.8 - 6.1 Volatility rate range 81.63 % - 83.55 % 71.06 % - 82.54 % Fair value of common stock range $ 3.89 - $ 20.50 $ 3.63 - $ 12.50
Summary of Stock Option Activity	The following table summarizes the Company’s stock option activity: Number Weighted-Average Weighted-Average Aggregate Intrinsic Outstanding as of December 31, 2022 3,300,935 $ 6.29 9.26 $ 18,346 Granted 297,556 10.43 Exercised ( 292,444 ) 2.65 Forfeited or canceled ( 189,005 ) 6.12 Outstanding as of December 31, 2023 3,117,042 $ 7.04 8.34 $ 3,409 Vested and expected to vest as of December 31, 2023 3,117,042 $ 7.04 8.34 $ 3,409 Vested and exercisable as of December 31, 2023 1,313,352 $ 5.08 7.86 $ 2,342
Summary of RSU activity	A summary of the RSU activity during the year ended December 31, 2023 is as follows: Restricted Stock Units Weighted-Average Unvested at December 31, 2022 1,787,152 $ 12.49 Granted 563,060 $ 11.20 Vested ( 566,260 ) $ 12.52 Forfeited ( 24,034 ) $ 10.86 Unvested at December 31, 2023 1,759,918 $ 12.09
Summary of Share-based Compensation Expense	Stock-based compensation expense included in the Company’s consolidated statements of operations and comprehensive loss is as follows (in thousands): Year Ended December 31, 2023 2022 General and administrative $ 9,089 $ 1,396 Research and development 2,529 789 Total stock-based compensation expense $ 11,618 $ 2,185

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Summary of Effective Income Tax Rate	The effective income tax rate differed from the amount computed by applying the federal statutory rate to the Company’s loss before income taxes as follows: December 31, 2023 2022 Tax effected at statutory rate 21.0 % 21.0 % State taxes 6.0 % 7.0 % Stock-based compensation ( 1.3 %) ( 0.5 %) Executive compensation ( 1.7 %) ( 0.7 %) Federal research and development credits 4.4 % 1.3 % Change in valuation allowance ( 28.5 %) ( 28.1 %) Total ( 0.1 %) — %
Summary of Total Deferred Tax Assets	The Company's total deferred tax assets at December 31, 2023 and 2022 are as follows (in thousands): December 31, 2023 2022 Deferred Tax Assets Net operating loss carryforward $ 9,395 $ 6,137 R&D credit carryovers 3,985 1,015 Section 174 R&D amortization 13,819 5,093 Operating lease liabilities 1,134 1,309 Accrued expenses and other current liabilities 919 528 Capitalized licenses 3,482 2,039 Other 554 226 33,288 16,347 Valuation allowance ( 31,761 ) ( 14,562 ) Deferred tax asset 1,527 1,785 Deferred Tax Liabilities Property and equipment ( 457 ) ( 531 ) Operating lease right-of-use assets ( 1,070 ) ( 1,254 ) Deferred tax liability ( 1,527 ) ( 1,785 ) Net deferred tax asset $ — $ —

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Net Loss Per Share	Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share amounts): December 31, 2023 2022 Numerator: Net loss attributable to common stockholders—basic and diluted $ ( 60,388 ) $ ( 31,167 ) Denominator: Weighted-average common stock outstanding—basic and diluted 22,078,190 4,121,912 Net loss per share—basic and diluted $ ( 2.74 ) $ ( 7.56 )
Summary of Potentially Dilutive Securities	The Company excluded the following shares from the computation of diluted net loss per share attributable to common stockholders as of December 31, 2023 and 2022 because including them would have had an anti-dilutive effect: December 31, 2023 2022 Options to purchase common stock 3,117,042 3,300,935 Unvested restricted stock units 1,759,918 1,787,152

Nature of the Business - Additi

Nature of the Business - Additional Information (Details) $ / shares in Units, $ in Thousands					1 Months Ended	12 Months Ended
	Dec. 15, 2023 USD ($)	Dec. 16, 2022 shares	Dec. 14, 2022 USD ($)	Nov. 17, 2022 USD ($) $ / shares shares	Dec. 16, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 shares
Organization Consolidation Presentation Of Financial Statements [Line Items]
Reverse stock split conversion ratio				0.406
Payment of underwriting discounts and commissions						$ 1,032	$ 2,773
Proceeds from issuance of common stock upon Concurrent Private Placement, net of placement agent fee				$ 4,700			4,650
Net loss						60,388	31,167
Accumulated deficit						116,420	56,032
Cash, Cash Equivalents, and Investments						$ 127,500
Proceeds from Issuance Initial Public Offering							$ 99,808
Convertible Preferred Stock
Organization Consolidation Presentation Of Financial Statements [Line Items]
Temporary Equity, Shares Outstanding | shares								27,471,911
Initial Public Offering
Organization Consolidation Presentation Of Financial Statements [Line Items]
Sale of Stock, Price Per Share | $ / shares				$ 12.5
Description of reverse stock spilt						In connection with the IPO, the Company effected a 1-for-2.466 reverse stock split of the Company’s common stock and adjusted the ratio at which the Company’s preferred stock is convertible into common stock, the number of shares available for issuance under the 2019 Stock Incentive Plan (“2019 Plan”) and the number of options and exercise prices of options granted under the 2019 Plan as a result of the 1-for-2.466 reverse stock split.
Initial Public Offering | Common Stock
Organization Consolidation Presentation Of Financial Statements [Line Items]
Issuance of common stock | shares				7,550,000			8,585,540
Proceeds from Issuance Initial Public Offering				$ 94,400
Initial Public Offering | Common Stock | Convertible Preferred Stock
Organization Consolidation Presentation Of Financial Statements [Line Items]
Convertible preferred stock converted into common stock shares | shares				11,140,262
Concurrent Private Placement
Organization Consolidation Presentation Of Financial Statements [Line Items]
Sale of Stock, Price Per Share | $ / shares				$ 12.5
Concurrent Private Placement | Common Stock
Organization Consolidation Presentation Of Financial Statements [Line Items]
Issuance of common stock | shares				400,000			400,000
Underwriters
Organization Consolidation Presentation Of Financial Statements [Line Items]
Issuance of common stock | shares		1,035,540
Gross proceeds from exercise of option			$ 12,900
Underwriters | Common Stock
Organization Consolidation Presentation Of Financial Statements [Line Items]
Underwriters option to purchase common stock | shares				1,132,500
IPO and Option Exercise
Organization Consolidation Presentation Of Financial Statements [Line Items]
Aggregate net proceeds received from IPO and option exercise			99,800
Payment of underwriting discounts and commissions					$ 7,500
Offering expenses payable			$ 3,600
ATM Program | Maximum
Organization Consolidation Presentation Of Financial Statements [Line Items]
Aggregate offering price	$ 300,000
ATM Program | Sale Agreement | Maximum
Organization Consolidation Presentation Of Financial Statements [Line Items]
Issuance and sale of common stock	$ 100,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Property and Equipment (Details)	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]	Leasehold Improvements
Laboratory Equipment and Computer Equipment
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	7 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Summary of Significant Accounting Policies [Line Items]
Deferred offering costs	$ 300,000
Other income, net	6,715,000	$ 1,490,000
Interest income	7,000,000	1,500,000
Leasehold improvements		0
Impairment losses on long lived assets	0	0
Research and development expense	46,024,000	23,949,000
Foreign currency transaction gains (losses)	100,000	0
Unrecognized tax benefits	$ 0	0
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 01, 2023
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]	true
Accounting Standards Update [Extensible Enumeration]	us-gaap:AccountingStandardsUpdate201613Member
Lilly Agreement
Summary of Significant Accounting Policies [Line Items]
Research and development expense	$ 0	$ 0

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Segment Information - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) Segment
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segment | Segment	1
Number of reportable segment | Segment	1
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets | $	$ 5.7
Sweden
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets | $	$ 2.2

Investments - Summary of Amorti

Investments - Summary of Amortized Cost and Estimated Fair Value of Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost		$ 140,208
Gross Unrealized Gains		71
Gross Unrealized Losses		(166)
Fair Value		140,113
Amortization Cost, Short-term investments	$ 91,526
Gross Unrealized Gains, Short-term investments	22
Gross Unrealized Losses, Short-term investments	(105)
Short-term investments	91,443
US Treasury Securities
Debt Securities, Available-for-Sale [Line Items]
Amortization Cost, Short-term investments	41,470	32,174
Gross Unrealized Gains, Short-term investments	22	3
Gross Unrealized Losses, Short-term investments	(19)	(34)
Short-term investments	41,473	32,143
Amortization Cost, Long-term investments		7,242
Gross Unrealized Losses, Long-term investments		(4)
Long-term investments		7,238
US Government-Sponsored Enterprises Securities
Debt Securities, Available-for-Sale [Line Items]
Amortization Cost, Short-term investments	50,056	66,106
Gross Unrealized Gains, Short-term investments		68
Gross Unrealized Losses, Short-term investments	(86)	(85)
Short-term investments	$ 49,970	66,089
Amortization Cost, Long-term investments		34,686
Gross Unrealized Losses, Long-term investments		(43)
Long-term investments		$ 34,643

Investments - Additional Inform

Investments - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Investments, contractual maturities short-term investments	1 year	1 year
Unrealized loss position less than 12 months	$ 59,900,000
Unrealized losses on investments	100,000	$ 200,000
Unrealized loss position greater than 12 months	0
Allowance for credit losses	$ 0
Minimum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investments, contractual maturities long-term investments		1 year
Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investments, contractual maturities long-term investments		2 years

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 91,443
Short-term investments	91,526
Investments		$ 140,113
US Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	41,473	32,143
Long-term investments		7,238
Short-term investments	41,470	32,174
Long-term investments		7,242
US Government-Sponsored Enterprises Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	49,970	66,089
Long-term investments		34,643
Short-term investments	50,056	66,106
Long-term investments		34,686
Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	122,634	164,195
Recurring | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value	31,191	24,082
Recurring | US Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	41,473	32,143
Long-term investments		7,238
Recurring | US Government-Sponsored Enterprises Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	49,970	66,089
Long-term investments		34,643
Recurring | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	72,664	63,463
Recurring | Level 1 | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents, fair value	31,191	24,082
Recurring | Level 1 | US Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	41,473	32,143
Long-term investments		7,238
Recurring | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total assets measured at fair value	49,970	100,732
Recurring | Level 2 | US Government-Sponsored Enterprises Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 49,970	66,089
Long-term investments		$ 34,643

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value measurement with unobservable inputs reconciliation liability transfers between levels	$ 0	$ 0
Preferred stock, shares, issued	0	0

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Total property and equipment	$ 4,435	$ 2,512
Less: accumulated depreciation	(956)	(420)
Property and equipment, net	3,479	2,092
Laboratory and Computer Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	2,955	2,340
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	172	$ 172
Construction in Progress
Property Plant And Equipment [Line Items]
Total property and equipment	$ 1,308

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 536	$ 364

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued compensation and benefits	$ 3,860	$ 2,662
Accrued research and development expenses	2,661	790
Accrued legal, accounting and other professional fees	667	648
Accrued other	190	44
Accrued offering costs		673
Deferred sublease income		69
Total accrued expenses and other current liabilities	$ 7,378	$ 4,886

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	1 Months Ended				12 Months Ended
	Dec. 31, 2023	May 31, 2021 ft²	Apr. 30, 2021 USD ($)	Oct. 31, 2020	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Lessee Lease Description [Line Items]
Sublease rent income					$ 134	$ 537
Variable lease expense					$ 492	$ 519
Weighted-average remaining lease term	4 years 2 months 12 days				4 years 2 months 12 days	5 years 3 months 18 days
Weighted-average discount rate	8.30%				8.30%	7.86%
Cash paid for measurement of lease liabilities					$ 1,100	$ 1,100
Arsenal Way Lease
Lessee Lease Description [Line Items]
Lessee, operating lease, commencement month and year			2021-04
Lessee operating lease, renewal term			5 years
Lessee, operating lease, initial term			7 years
Lessee, operating lease, option to extend					The lease has an initial term from the rent commencement date, which is a month after the lease commencement date, of approximately seven years, with an option to extend the term for an additional five years at then-market rental rates.
Lessee, Operating Lease, Existence of Option to Extend [true false]			true
Letter of credit			$ 300
Tenant improvements cost			700
Base rent			$ 1,000
Annual rent increase percentage			3%
Rentable square feet | ft²		6,330
Sublease expiration, month and year		2023-03
Sublease rent income					$ 200	$ 800
Lund, Sweden
Lessee Lease Description [Line Items]
Lessee, operating lease, commencement month and year	2023-12			2020-10
Lessee, operating lease, expiration month and year				2023-09
Lessee operating lease, renewal term	3 years			3 years	3 years
Lessee, operating lease, initial term	3 years				3 years
Lessee, Operating Lease, Existence of Option to Extend [true false]	true			true

Leases - Summary of Presentatio

Leases - Summary of Presentation of Operating Leases on Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets
Operating lease right-of-use assets	$ 4,429	$ 4,770
Current liabilities:
Operating lease liabilities, current	877	726
Noncurrent:
Operating lease liabilities, long-term	3,767	4,235
Total lease liabilities	$ 4,644	$ 4,961

Leases - Schedule of Components

Leases - Schedule of Components of Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating lease cost	$ 1,140	$ 1,143
Variable lease cost	492	519
Sublease income	(134)	(537)
Total lease cost	$ 1,498	$ 1,125

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Annual Lease Commitments under Non-cancellable Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
2024	$ 1,221
2025	1,315
2026	1,349
2027	1,200
2028	404
Total lease payments	5,489
Less: interest	(845)
Present value of operating lease liabilities	$ 4,644	$ 4,961

License Agreement - Additional

License Agreement - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2021	Dec. 31, 2023	Dec. 31, 2022
Commitment And Contingencies [Line Items]
Research and development expense		$ 46,024,000	$ 23,949,000
Lilly Agreement
Commitment And Contingencies [Line Items]
Upfront payment	$ 5,000,000
Research and development expense		0	$ 0
Royalties incurred		$ 0
Lilly Agreement | Maximum
Commitment And Contingencies [Line Items]
Tiered percentage royalty on annual net sales	10%
Lilly Agreement | Development and Commercial Milestone
Commitment And Contingencies [Line Items]
Milestone payments	$ 168,000,000

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Temporary Equity [Line Items]
Issuance costs	$ 1,032	$ 2,773

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - $ / shares	Dec. 31, 2023	Dec. 31, 2022	Oct. 31, 2022
Class of Stock [Line Items]
Preferred stock, authorized	10,000,000	10,000,000
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares, issued	0	0
Preferred stock, shares, outstanding	0	0
Common stock, shares authorized	500,000,000	500,000,000
Common stock, per share value	$ 0.001	$ 0.001
Initial Public Offering
Class of Stock [Line Items]
Preferred stock, authorized			10,000,000
Preferred stock, par value			$ 0.001

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Common Stock Shares Reserved for the Potential Conversion of Outstanding Preferred Stock and Exercise of Stock Options (Details) - shares	Dec. 31, 2023	Dec. 31, 2022
Class of Stock Disclosures [Abstract]
Options to purchase common stock	3,117,042	3,300,935
Unvested restricted stock units	1,759,918	1,787,152
Remaining shares reserved for future issuance	2,107,745	733,636
Total	6,984,705	5,821,723

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Oct. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2023	Sep. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 11,618,000	$ 2,185,000
Number of shares reserved for issuance		2,107,745	733,636
Options outstanding		3,117,042	3,300,935
Unvested restricted stock units		1,759,918	1,787,152
Number of common shares issued for each RSU vested		22,522,644	21,920,402
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grant date fair value of the stock options granted		$ 20.5	$ 12.5
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grant date fair value of the stock options granted		$ 3.89	$ 3.63
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
Fair value RSUs vested		$ 7,100,000	$ 0
Expected to be recognized as stock-based compensation expense, RSUs		$ 19,600,000
Weighted-average recognition period		2 years 3 months 18 days
Unvested restricted stock units		1,759,918	1,787,152
Weighted average granted date fair value		$ 11.2	$ 12.49
Number of common shares issued for each RSU vested		1
2019 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of options exercised		$ 2,100,000	$ 100,000
2019 Stock Incentive Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding					2,148,679
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual term of stock option award		10 years
Weighted-average grant date fair value of the stock options granted		$ 7.59	$ 5.52
Unrecognized stock-based compensation expense		$ 10,500,000
Weighted-average recognition period		2 years 6 months
Total fair value of options vested		$ 4,200,000	$ 500,000
Stock Options | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
2022 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance	5,606,723	1,369,341
New shares issued	2,555,271
Increase in common stock reserved for issuance as percentage of outstanding shares of common stock	5%
2022 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 0
Number of shares reserved for issuance	215,000	434,204
New shares issued		0
Increase in common stock reserved for issuance as percentage of outstanding shares of common stock	1%
2023 Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance		304,200		450,000
Options outstanding		123,825
2023 Inducement Plan | RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested restricted stock units		21,975

Stock-based Compensation - Assu

Stock-based Compensation - Assumptions of Grant Date Fair Value of Stock Options Granted (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate range, minimum	3.40%	2.69%
Risk-free interest rate range, maximum	4.84%	4.15%
Dividend yield	0%	0%
Volatility rate range, minimum	81.63%	71.06%
Volatility rate range, maximum	83.55%	82.54%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life of options (years)	5 years 9 months 18 days	5 years 9 months 18 days
Fair value of common stock range	$ 3.89	$ 3.63
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life of options (years)	6 years 1 month 6 days	6 years 1 month 6 days
Fair value of common stock range	$ 20.5	$ 12.5

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Number of Shares, Outstanding, beginning of period	3,300,935
Number of Shares, Granted	297,556
Number of Shares, Exercised	(292,444)
Number of Shares, Forfeited or canceled	(189,005)
Number of Shares, Outstanding, Ending of period	3,117,042	3,300,935
Number of Shares, Vested and expected to vest, Ending of period	3,117,042
Number of Shares, Vested and exercisable, Ending of period	1,313,352
Weighted-Average Exercise Price, Outstanding, beginning of period	$ 6.29
Weighted-Average Exercise Price, Granted	10.43
Weighted-Average Exercise Price, Exercised	2.65
Weighted-Average Exercise Price, Fortified or canceled	6.12
Weighted-Average Exercise Price, Outstanding, ending of period	7.04	$ 6.29
Weighted-Average Exercise Price, Vested and expected to vest, ending of period	7.04
Weighted-Average Exercise Price, Vested and exercisable, ending of period	$ 5.08
Weighted Average Remaining Contractual Term (in years), Outstanding	8 years 4 months 2 days	9 years 3 months 3 days
Weighted Average Remaining Contractual Term (in years), Vested and expected to vest, ending of period	8 years 4 months 2 days
Weighted Average Remaining Contractual Term (in years), Vested and exercisable, ending of period	7 years 10 months 9 days
Aggregate Intrinsic Value	$ 3,409	$ 18,346
Aggregate Intrinsic Value, Vested and expected to vest, ending of period	3,409
Aggregate Intrinsic Value, Vested and exercisable, ending of period	$ 2,342

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of RSU activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted Stock Units, Unvested at December 31, 2022	1,787,152
Restricted Stock Units, Unvested at December 31, 2023	1,759,918	1,787,152
RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted Stock Units, Unvested at December 31, 2022	1,787,152
Restricted Stock Units, Granted	563,060
Restricted Stock Units, Vested	(566,260)
Restricted Stock Units, Forfeited	(24,034)
Restricted Stock Units, Unvested at December 31, 2023	1,759,918	1,787,152
Weighted-Average Grant Date Fair Value, Unvested at December 31, 2022	$ 12.49
Weighted-Average Grant Date Fair Value, Granted	11.2	$ 12.49
Weighted-Average Grant Date Fair Value, Vested	12.52
Weighted-Average Grant Date Fair Value, Forfeited	10.86
Weighted-Average Grant Date Fair Value, Unvested at December 31, 2023	$ 12.09	$ 12.49

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 11,618	$ 2,185
General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	9,089	1,396
Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 2,529	$ 789

Income Taxes - Summary of Effec

Income Taxes - Summary of Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Tax effected at statutory rate%	21%	21%
State taxes	6%	7%
Stock-based compensation	(1.30%)	(0.50%)
Executive compensation	(1.70%)	(0.70%)
Federal research and development credits	4.40%	1.30%
Change in valuation allowance	(28.50%)	(28.10%)
Total	(0.10%)

Income Taxes - Summary of Total

Income Taxes - Summary of Total Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred Tax Assets
Net operating loss carryforward	$ 9,395	$ 6,137
R&D credit carryovers	3,985	1,015
Section 174 R&D amortization	13,819	5,093
Operating lease liabilities	1,134	1,309
Accrued expenses and other current liabilities	919	528
Capitalized licenses	3,482	2,039
Other	554	226
Deferred Tax Assets, Gross, Total	33,288	16,347
Valuation allowance	(31,761)	(14,562)
Deferred tax asset	1,527	1,785
Deferred Tax Liabilities
Property and equipment	(457)	(531)
Operating lease right-of-use assets	(1,070)	(1,254)
Deferred tax liability	$ (1,527)	$ (1,785)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
Increase in valuation allowance	$ 17,200,000
Federal operating loss carryforwards	33,000,000
State operating loss carryforwards	$ 35,300,000
Operating loss carryforwards expiration year	2038
R&D credit against employer portion of payroll tax	$ 500,000
Unrecognized tax benefits	0	$ 0
Unrecognized tax benefits reserves for uncertain tax positions	0	0
Estimated interest or penalties were recognized on uncertain tax positions	$ 0	$ 0
Minimum
Income Taxes [Line Items]
Research and experimental expenditures amortization period	5 years
Maximum
Income Taxes [Line Items]
Research and experimental expenditures amortization period	15 years
Gross receipts	$ 5,000,000
Federal
Income Taxes [Line Items]
Research and development tax credit carryforwards	3,100,000
State
Income Taxes [Line Items]
Research and development tax credit carryforwards	$ 1,200,000

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Comprehensive loss:
Net loss attributable to common stockholders - basic and diluted	$ (60,388)	$ (31,167)
Denominator:
Weighted-average common stock outstanding—basic	22,078,190	4,121,912
Weighted-average common stock outstanding—diluted	22,078,190	4,121,912
Net loss per share—basic	$ (2.74)	$ (7.56)
Net loss per share—diluted	$ (2.74)	$ (7.56)

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Potentially Dilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Options to purchase common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	3,117,042	3,300,935
Unvested restricted stock units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	1,759,918	1,787,152

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Jun. 30, 2022	Jan. 31, 2021	Dec. 31, 2023	Dec. 31, 2022
Lilly Agreement
Loss Contingencies [Line Items]
Upfront payment		$ 5,000,000
Royalties incurred			$ 0
Lilly Agreement | Maximum
Loss Contingencies [Line Items]
Tiered percentage royalty on annual net sales		10%
Akoya Agreement
Loss Contingencies [Line Items]
Upfront payment	$ 600,000
Obligation to pay upon achievement of specified development milestones	$ 17,300,000
Milestone payments			7,000,000
Accounts Payable | Akoya Agreement
Loss Contingencies [Line Items]
Milestones due amounts			1,300,000
Research and Development Expense | Akoya Agreement
Loss Contingencies [Line Items]
Milestones expenses			$ 6,000,000	$ 2,300,000
Development and Commercial Milestone | Lilly Agreement
Loss Contingencies [Line Items]
Milestone payments		$ 168,000,000