IO Biotech (IOBT) 10-Q 13 Aug 24 2024 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2024	Aug. 08, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2024
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2024
Current Fiscal Year End Date	--12-31
Entity Registrant Name	IO Biotech, Inc.
Entity Central Index Key	0001865494
Entity File Number	001-41008
Entity Tax Identification Number	87-0909276
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	Ole Maaløes Vej 3
Entity Address, City or Town	Copenhagen N
Entity Address, Country	DK
Entity Address, Postal Zip Code	DK-2200
City Area Code	+45
Local Phone Number	7070 2980
Title of each class	Common Stock, par value $0.001 per share
Trading Symbol(s)	IOBT
Name of each exchange on which registered	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		65,880,914
Document Quarterly Report	true
Document Transition Report	false

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 100,747	$ 143,193
Prepaid expenses and other current assets	6,905	4,062
Total current assets	107,652	147,255
Restricted cash	268	268
Property and equipment, net	735	847
Right of use lease asset	1,936	2,259
Other non-current assets	876	89
Total non-current assets	3,815	3,463
Total assets	111,467	150,718
Current liabilities
Accounts payable	5,016	3,878
Lease liability - current	678	655
Accrued expenses and other current liabilities	8,029	11,184
Total current liabilities	13,723	15,717
Lease liability - noncurrent	1,472	1,839
Total non-current liabilities	1,472	1,839
Total liabilities	15,195	17,556
Commitments and contingencies (Note 9)
Stockholders' equity
Preferred stock, par value of $0.001 per share; 5,000,000 shares authorized, no shares issued and outstanding as of June 30, 2024 and December 31, 2023
Common stock, par value of $0.001 per share; 300,000,000 shares authorized at June 30, 2024 and December 31, 2023; 65,880,914 shares issued and outstanding as of June 30, 2024 and December 31, 2023, respectively	66	66
Additional paid-in capital	409,797	406,587
Accumulated deficit	(303,965)	(263,822)
Accumulated other comprehensive loss	(9,626)	(9,669)
Total stockholders' equity	96,272	133,162
Total liabilities and stockholders' equity	$ 111,467	$ 150,718

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2024	Dec. 31, 2023
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	65,880,914	65,880,914
Common stock, shares outstanding	65,880,914	65,880,914

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Operating expenses
Research and development	$ 15,848	$ 16,504	$ 30,159	$ 28,404
General and administrative	5,685	5,348	11,571	11,372
Total operating expenses	21,533	21,852	41,730	39,776
Loss from operations	(21,533)	(21,852)	(41,730)	(39,776)
Other income (expense)
Currency exchange (loss) gain, net	(90)	10	(552)	268
Interest income	1,311	1,196	2,928	2,224
Total other income (expense), net	1,221	1,206	2,376	2,492
Loss before income tax expense	(20,312)	(20,646)	(39,354)	(37,284)
Income tax expense	374	532	789	938
Net loss	(20,686)	(21,178)	(40,143)	(38,222)
Net loss attributable to common shareholders	$ (20,686)	$ (21,178)	$ (40,143)	$ (38,222)
Net loss per common share, basic	$ (0.31)	$ (0.74)	$ (0.61)	$ (1.33)
Net loss per common share, diluted	$ (0.31)	$ (0.74)	$ (0.61)	$ (1.33)
Weighted-average number of shares used in computing net loss per common share, basic	65,880,914	28,815,267	65,880,914	28,815,267
Weighted-average number of shares used in computing net loss per common share, diluted	65,880,914	28,815,267	65,880,914	28,815,267
Other comprehensive loss
Net loss	$ (20,686)	$ (21,178)	$ (40,143)	$ (38,222)
Foreign currency translation	(151)	(141)	43	376
Total comprehensive loss	$ (20,837)	$ (21,319)	$ (40,100)	$ (37,846)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance at Dec. 31, 2022	$ 138,854	$ 29	$ 326,705	$ (10,141)	$ (177,739)
Balance, shares at Dec. 31, 2022		28,815,267
Equity-based compensation	3,512		3,512
Foreign currency translation	376			376
Net loss	(38,222)				(38,222)
Balance at Jun. 30, 2023	104,520	$ 29	330,217	(9,765)	(215,961)
Balance, shares at Jun. 30, 2023		28,815,267
Balance at Dec. 31, 2022	138,854	$ 29	326,705	(10,141)	(177,739)
Balance, shares at Dec. 31, 2022		28,815,267
Net loss	(86,100)
Balance at Dec. 31, 2023	133,162	$ 66	406,587	(9,669)	(263,822)
Balance, shares at Dec. 31, 2023		65,880,914
Equity-based compensation	3,210		3,210
Foreign currency translation	43			43
Net loss	(40,143)				(40,143)
Balance at Jun. 30, 2024	$ 96,272	$ 66	$ 409,797	$ (9,626)	$ (303,965)
Balance, shares at Jun. 30, 2024		65,880,914

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities
Net loss	$ (40,143)	$ (38,222)
Adjustment to reconcile net loss to net cash used in operating activities
Depreciation	127	102
Equity-based compensation	3,210	3,512
Amortization of right of use lease asset	298	259
Foreign currency loss (gain)	552	(268)
Changes in operating assets and liabilities
Prepaid expenses and other current assets	(2,843)	2,689
Other non-current assets	(787)	(806)
Accounts payable	1,139	460
Lease liability	(312)	(319)
Accrued expenses and other current liabilities	(3,155)	(359)
Net cash used in operating activities	(41,914)	(32,952)
Cash flows from investing activities
Purchase of property and equipment	(23)	(187)
Net cash used in investing activities	(23)	(187)
Cash flows from financing activities
Net cash provided by financing activities	0	0
Net decrease in cash, cash equivalents and restricted cash	(41,937)	(33,139)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(509)	644
Cash, cash equivalents and restricted cash, beginning of period	143,461	142,858
Cash, cash equivalents and restricted cash, end of period	101,015	110,363
Components of cash, cash equivalents, and restricted cash
Cash and cash equivalents	100,747	110,095
Restricted cash	268	268
Total cash, cash equivalents and restricted cash	$ 101,015	$ 110,363

Description of Business, Organi

Description of Business, Organization and Liquidity	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business, Organization and Liquidity	1. Description of Business, Organization and Liquidity Business IO Biotech, Inc. is a clinical-stage biopharmaceutical company developing novel, immune-modulating therapeutic cancer vaccines based on our T-win® platform. As used in these financial statements, unless the context otherwise requires, references to the “Company,” “we,” “us,” and “our” refer to IO Biotech, Inc. and its subsidiaries. Corporate Reorganization IO Biotech ApS was incorporated in Denmark in December 2014. In November 2021, we completed a corporate reorganization (the “Corporate Reorganization”) whereby IO Biotech ApS became a wholly-owned subsidiary of the Company. In connection with the corporate reorganization, each issued and outstanding Class A ordinary share ($ 0.16 par value) was exchanged on a one-for-one basis into shares of common stock of the Company ($ 0.001 par value). Each Class B and Class C preference share of IO Biotech ApS was exchanged on a one-for-one basis into shares of Class B and Class C preferred stock of the Company. IO Bio US, Inc., a wholly owned subsidiary of IO Biotech ApS, was incorporated in Delaware in May 2021. IO Biotech Limited, a wholly owned subsidiary of IO Biotech ApS, was incorporated in the UK in August 2021. In November 2021, the Company engaged in a series of transactions, referred to collectively as the Corporate Reorganization. As a result of the Corporate Reorganization, IO Biotech ApS became a wholly-owned subsidiary of IO Biotech, Inc. IO Biotech, Inc. is a holding company formed in October 2021, which, prior to our initial public offering (“IPO”), had nominal assets and no liabilities, contingencies, or commitments, and which has not conducted any operations prior to our IPO other than acquiring the entire issued and outstanding stock of IO Biotech ApS. The Company, IO Biotech ApS, and the holders of all of the issued and outstanding equity interests of IO Biotech ApS entered into a Share Contribution and Exchange Agreement, dated as of October 29, 2021, pursuant to which the Corporate Reorganization was effected. IPO In November 2021, we completed our IPO, selling an aggregate of 8,222,500 shares of common stock at a price to the public of $ 14.00 per share, including 1,072,500 shares of common stock sold pursuant to the underwriters’ exercise of their option to purchase additional shares of common stock. We received net proceeds from the IPO, after deducting underwriting discounts and commissions and other offering costs of $ 103.3 million. Immediately prior to the consummation of the IPO, all outstanding shares of our Class A ordinary shares and Class B and Class C convertible preference shares were converted into 20,592,413 shares of common stock. Upon the closing of the IPO on November 9, 2021, a total of 28,815,267 shares of common stock were issued and outstanding. Our common stock began trading on the Nasdaq Global Market on November 5, 2021 under the symbol “IOBT.” On November 9, 2021, we amended and restated the certificate of incorporation of IO Biotech, Inc. to authorize the issuance of 300,000,000 shares of common stock and 5,000,000 shares of preferred stock. The shares of preferred stock are currently undesignated. August 2023 Private Placement On August 9, 2023, the Company completed a private placement transaction (the “Private Placement”), pursuant to which we sold an aggregate of 37,065,647 shares of the Company’s common stock, par value $ 0.001 per share, and 37,065,647 warrants to purchase up to 37,065,647 shares of common stock (the “Warrants”) to certain institutional investors and existing shareholders (the “Purchasers”). Each Purchaser’s Warrant is exercisable for a number of shares of common stock equal to one hundred percent of the aggregate number of shares of common stock purchased by such Purchaser. The purchase price per share of common stock and Warrant was $ 2.025 (the “Purchase Price”). The Company received net proceeds from the Private Placement, after deducting $ 3.2 million in underwriting discounts and commissions and other offering costs, of $ 71.9 million. Refer to Note 10, "Stockholders' Equity" in the accompanying notes to our unaudited consolidated financial statements for the period ended June 30, 2024 for additional information on the Private Placement. At-The-Market Equity Program On February 15, 2023, we filed a new prospectus supplement with the U.S. Securities and Exchange Commission (the “SEC”) with respect to the offer and sale of shares of our Common Stock, with an aggregate offering price of up to $ 19.5 million, establishing an at-the-market equity program. We also entered into a common stock sales agreement, dated February 15, 2023 (the “Sales Agreement”) by and between the Company and Cowen and Company, LLC for shares with an aggregate offering price of up to $ 75.0 million, through which we may, from time to time, sell shares through Cowen and Company, LLC, acting as agent and/or principal. Any shares offered and sold through the at-the-market equity program will be issued pursuant to the Company’s Registration Statement on Form S-3 (File No. 333-269569), which was declared effective on February 10, 2023, the prospectus supplement related to the offering that forms a part of the registration statement, and any applicable prospectus supplements that may form a part of the registration statement in the future. The aggregate market value of shares eligible for sale under the prospectus supplement and under the Sales Agreement will be subject to the limitations of General Instruction I.B.6 of Form S-3, to the extent required under such instruction. We have no t issued any shares pursuant to our at-the-market equity program as of June 30, 2024. Risks and Uncertainties We are subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance reporting capabilities. Our product candidates are in preclinical research and clinical development. There can be no assurance that our research and development will be successfully completed, that adequate protection for our intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if our product development efforts are successful, it is uncertain when, if ever, we will generate significant revenue from product sales. We operate in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, we are dependent upon the services of our employees and consultants. Liquidity Considerations and Going Concern Basis of Accounting Since inception, we have devoted substantially all of our efforts to business planning, conducting research and development, recruiting management and technical staff, and raising capital. We have financed our operations primarily through the issuance of convertible preference shares, convertible notes, our IPO and the Private Placement. Our continued discovery and development of product candidates will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if product development efforts are successful, it is uncertain when, if ever, we will realize significant revenue from product sales. As of June 30, 2024, we had an accumulated deficit of $ 304.0 million. We have incurred losses and negative cash flows from operations since inception, including net losses of $ 40.1 million and $ 86.1 million for the six months ended June 30, 2024 and the year ended December 31, 2023, respectively. We expect that our operating losses and negative cash flows will continue for the foreseeable future as we continue to develop our product candidates. We currently expect that our cash and cash equivalents of $ 100.7 million as of June 30, 2024 will be sufficient to fund our operating expenses and capital requirements for at least 12 months from the date the financial statements are issued. On this basis, the consolidated financial statements are prepared on a going concern basis of accounting. However, additional funding will be necessary to fund future discovery research, preclinical and clinical activities. We will seek additional funding through public financings, debt financings, collaboration agreements, strategic alliances and licensing arrangements. Although we have been successful in raising capital in the past, there is no assurance that we will be successful in obtaining such additional financing on acceptable terms, or at all, and we may not be able to enter into collaborations or other arrangements. If we are unable to obtain funding, we could be forced to delay, reduce or eliminate our research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect our business prospects, even our ability to continue operations.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies There have been no changes to the significant accounting policies disclosed in Note 2 to the Company’s annual financial statements for the years ended December 31, 2023 and 2022 included in its Annual Report on Form 10-K filed with the SEC. Unaudited Financial Information The accompanying unaudited interim consolidated financial statements included herein have been prepared in conformity with generally accepted accounting principles in the United States of America (“U.S. GAAP”), and pursuant to the rules and regulations of the SEC. In the Company’s opinion, the information furnished herein reflects all adjustments, all of which are of a normal and recurring nature and necessary for a fair presentation of the financial position and results of operations for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period. Unaudited interim financial statements and footnotes should be read in conjunction with the audited financial statements and footnotes included in the Company’s Annual Report filed on Form 10-K for the fiscal year ended December 31, 2023 . Recently Adopted Accounting Standards In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity . ASU 2020-06 will simplify the accounting for convertible instruments by reducing the number of accounting models for convertible debt instruments and convertible preferred stock. Limiting the accounting models results in fewer embedded conversion features being separately recognized from the host contract as compared with current U.S. GAAP. Convertible instruments that continue to be subject to separation models are (i) those with embedded conversion features that are not clearly and closely related to the host contract, that meet the definition of a derivative, and that do not qualify for a scope exception from derivative accounting and (ii) convertible debt instruments issued with substantial premiums for which the premiums are recorded as paid-in capital. ASU 2020-06 also amends the guidance for the derivatives scope exception for contracts in an entity’s own equity to reduce form-over-substance-based accounting conclusions. ASU 2020-06 will be effective for us beginning after December 15, 2023. The Company has adopted the standard effective January 1, 2024 . The adoption of the standard has no t had a material impact on our financial statements or financial statement disclosures. Recently Issued Accounting Standards In October 2023, the FASB issued ASU 2023-06, Accounting Standards Update 2023-06—Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. ASU 2023-06 will eliminate disclosure requirements that are redundant, duplicative, overlapping, outdated, or superseded as a result of subsequent changes to SEC disclosure requirements, U.S. GAAP or technology. ASU 2023-06 is intended to better align U.S. GAAP requirements with those of the SEC and to facilitate the application of U.S. GAAP. The disclosure requirements would apply prospectively in the financial statements. ASU 2023-06 will be effective for us on the date on which the SEC’s removal of that related disclosure requirement from Regulation S-X or Regulation S-K becomes effective, if we are already subject to the SEC’s current disclosure requirements. For those current disclosure requirements we are not subject to, ASU 2023-06 will become effective two years after the date of such removal by the SEC. We are currently assessing the impact adoption of ASU 2023-06 will have on our financial statements and disclosures. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. ASU 2023-07 will improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. ASU 2023-07 will also enhance interim disclosure requirements, clarify circumstances in which an entity can disclose multiple segment measures of profit or loss, provide new segment disclosure requirements for entities with a single reportable segment and contain other disclosure requirements. The enhanced segment disclosure requirements apply retrospectively to all prior periods presented in the financial statements. ASU 2023-07 will be effective for us in the annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We are currently assessing the impact adoption of ASU 2023-07 will have on our financial statements and disclosures, but do not expect a material impact on the financial statements or disclosures. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. ASU 2023-09 will require disclosure of additional information in specified categories with respect to the reconciliation of the effective tax rate to the statutory rate (the rate reconciliation) for federal, state and foreign income taxes. ASU 2023-09 will also require information pertaining to taxes paid (net of refunds received) to be disaggregated for federal, state and foreign taxes and further disaggregated for specific jurisdictions to the extent the related amounts exceed a quantitative threshold. ASU 2023-09 will be effective for us in the annual periods beginning after December 15, 2024. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. We are currently assessing the impact adoption of ASU 2023-09 will have on our financial statements and disclosures. Other than the items noted above, there have been no new accounting pronouncements not yet effective or adopted in the current year that we believe have a significant impact, or potential significant impact, to our unaudited interim consolidated financial statements.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The following table presents information about our financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): June 30, 2024 Total Level 1 Level 2 Level 3 Assets Money market funds (1) $ 76,066 $ 76,066 $ — $ — Total assets measured at fair value $ 76,066 $ 76,066 $ — $ — December 31, 2023 Total Level 1 Level 2 Level 3 Assets Money market funds (1) $ 131,613 $ 131,613 $ — $ — Total assets measured at fair value $ 131,613 $ 131,613 $ — $ — (1) Money market funds with maturities of 90 days or less at the date of purchase are included within cash and cash equivalents in the accompanying consolidated balance sheets and are recognized at fair value. As of June 30, 2024 and December 31, 2023, the Company only held Level 1 financial instruments. There were no transfers among Level 1, Level 2 or Level 3 categories in the six months ended June 30, 2024 and the year ended December 31, 2023 .

License and Collaboration Agree

License and Collaboration Agreements	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
License and Collaboration Agreements	4. License and Collaboration Agreements In February 2018, we entered into a clinical collaboration with MSD International GmbH (“MSDIG”) to evaluate IO102 in combination with KEYTRUDA® (“pembrolizumab”) in first-line treatment of patients with metastatic non-small cell lung cancer. Under the terms of the collaboration with MSDIG, we will conduct an international Phase 1/2 study to evaluate a combination therapy of IO102 and KEYTRUDA®. We will sponsor the clinical trial and MSDIG will provide KEYTRUDA® to be used in the clinical trial free of charge. We and MSDIG will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102 for use in the study. The rights to the data from the clinical trial will be shared by us and MSDIG and we will maintain global commercial rights to IO102. In September 2021, we entered into a clinical collaboration with MSDIG and MSD International Business GmbH (“MSDIB”), another affiliate of Merck (collectively, “MSD”) to evaluate IO102-IO103 in combination with KEYTRUDA® versus KEYTRUDA® alone in treatment of patients with metastatic (advanced) melanoma. Under the terms of the collaboration with MSD, we are conducting an international Phase 3 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We are the sponsor of the clinical trial and MSD will provide KEYTRUDA® to be used in the clinical trial free of charge. We and MSD are responsible for our own internal costs and expenses to support the study and we will bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trial will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103. In December 2021, we entered into a clinical collaboration with MSD to evaluate IO102-IO103 in combination with KEYTRUDA® in previously untreated patients with three different tumor types— metastatic non-small cell lung cancer (“NSCLC”), squamous cell carcinoma of the head and neck (“SCCHN”), and urothelial bladder cancer (“UBC”). Under the terms of the collaboration with MSD, we are conducting an international Phase 2 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We are the sponsor of the clinical trial and MSD will provide KEYTRUDA® to be used in the clinical trial free of charge. We and MSD are responsible for our own internal costs and expenses to support the study and we will bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trial will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103. In November 2022, we entered into a clinical collaboration with MSD to evaluate IO102-IO103 in combination with KEYTRUDA® as a neo-adjuvant/adjuvant therapy for patients with metastatic melanoma and SCCHN. Under the terms of the collaboration with MSD, we will conduct an international Phase 2 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We will sponsor the clinical trial and MSD will provide KEYTRUDA® to be used in the clinical trial free of charge. We and MSD will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trial will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	6 Months Ended
	Jun. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current Assets	5. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consist of the following (in thousands): June 30, December 31, Prepaid contract research and development costs $ 3,239 $ — Prepaid income taxes 1,211 829 Research and development tax credit receivable 791 814 Insurance 651 1,352 Value-added tax refund receivable 239 313 Other 774 754 Total prepaid expenses and other current assets $ 6,905 $ 4,062

Property and Equipment, Net

Property and Equipment, Net	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	6. Property and Equipment, Net Property and equipment, net consist of the following (in thousands): June 30, December 31, Laboratory equipment $ 829 $ 836 Office furniture 235 238 Computer hardware 128 103 Less: accumulated depreciation ( 457 ) ( 330 ) Total property and equipment, net $ 735 $ 847 For the three months ended June 30, 2024 and 2023, the Company recognized $ 0.1 million of depreciation expense, respectively, in the consolidated statements of operations. For the six months ended June 30, 2024 and 2023, the Company recognized $ 0.1 million of depreciation expense, respectively, in the consolidated statements of operations.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	6 Months Ended
	Jun. 30, 2024
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	7. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consist of the following (in thousands): June 30, December 31, Accrued contract research and development costs $ 4,385 $ 6,153 Employee compensation costs 2,520 4,225 Professional fees 585 243 Other liabilities 539 563 Total accrued expenses and other current liabilities $ 8,029 $ 11,184

Leases

Leases	6 Months Ended
	Jun. 30, 2024
Leases [Abstract]
Leases	8. Leases As of June 30, 2024 , the Company is party to five operating leases for laboratory and office space. The Company’s finance leases are immaterial both individually and in the aggregate. In the consolidated balance sheet as of June 30, 2024, the Company has a right-of-use lease asset (“ROU”) balance of $ 1.9 million and a current and non-current lease liability of $ 0.7 million and $ 1.5 million, respectively, relating to the ROU lease asset. The balance of both the ROU lease asset and the lease liabilities primarily consists of future payments under the Company’s office and laboratory space leased in New York, New York, Rockville, Maryland and Copenhagen, Denmark. The Company is party to an operating lease in Copenhagen, Denmark for office space that commenced in March 2021 with the initial term set to expire in January 2025. Base rent for this initial lease was $ 0.1 million annually. The Company amended its operating lease in Copenhagen, Denmark on September 1, 2022 with a new term set to expire in December 2027. The base rent for the amended lease is $ 0.2 million annually. The Company is also party to an operating lease in Copenhagen, Denmark for laboratory space that commenced in January 2023 with the term set to expire in December 2027. The base rent for the lease is $ 0.04 million annually. The Company is party to an operating lease in New York, New York for office space that commenced in October 2021 with the initial term set to expire in January 2027. Base rent for this lease is $ 0.2 million annually. The Company is party to an operating lease in Rockville, Maryland for office and laboratory space that commenced in December 2021 with the initial term set to expire in May 2027. Base rent for this lease is $ 0.3 million annually. The Company is party to an immaterial operating lease in Newport, United Kingdom that commenced in June 2023. Rent expense for the three months ended June 30, 2024 and 2023 was $ 0.2 million , respectively. Rent expense for each of the six months ended June 30, 2024 and 2023 was $ 0.4 million , respectively. Quantitative information regarding the Company’s leases for the six months ended June 30, 2024 and 2023 is as follows (in thousands): Six Months Ended Six Months Ended Lease Cost June 30, 2024 June 30, 2023 Operating lease cost $ 369 $ 351 Operating cash flows paid for amounts included in the measurement of lease liabilities $ 385 $ 353 Operating lease liabilities arising from obtaining right-of-use assets $ — $ 235 Remaining average lease term (years) 3.0 4.0 Weighted average discount rate 6.3 % 6.3 % Future lease payments (undiscounted) under noncancelable leases are as follows at June 30, 2024 (in thousands): Future Lease Payments Amount Remainder of 2024 $ 394 2025 785 2026 791 2027 395 2028 — Thereafter — Total $ 2,365 The Company’s leases do not provide an explicit rate. Therefore, the Company used its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. The Company used the incremental borrowing rate on January 1, 2022 for operating leases that commenced prior to that date, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. Commitments and Contingencies Legal Proceedings From time to time, we may be party to litigation arising in the ordinary course of business. We were not subject to any material legal proceedings during the six months ended June 30, 2024 and the year ended December 31, 2023, and, to our knowledge, no material legal proceedings are currently pending or threatened. Contractual Obligations and Commitments We enter into contracts in the ordinary course of business with third-party service providers for clinical trials, preclinical research studies and testing, manufacturing and other services and products for operating purposes. These contracts generally provide for termination upon notice of 30 to 90 days, and therefore, we believe that our noncancelable obligations under these agreements are not material and we cannot reasonably estimate whether they will occur. However, in the event of a termination of any contracts with CROs or other institutions and with respect to active patients enrolled in our clinical trials, we may be financially obligated for a period beyond the contractual termination notice periods. We may also enter into additional research, manufacturing, supplier, lease and other agreements in the future, which may require up-front payments and even long-term commitments of cash. Indemnification Agreements We enter into certain types of contracts that contingently require us to indemnify various parties against claims from third parties. These contracts primarily relate to procurement, service, consultancy or license agreements under which we may be required to indemnify vendors, service providers or licensees for certain claims, including claims that may be brought against them arising from our acts or omissions with respect to our products, technology, intellectual property or services. The Company, as permitted under Delaware law and in accordance with its amended and restated certificate of incorporation and amended and restated bylaws and pursuant to indemnification agreements with certain of its officers and directors, indemnifies its officers and directors for certain events or occurrences, subject to certain limits, in which the officer or director incurs losses or expenses because he or she is or was serving at the Company’s request in such capacity. At the 2023 Annual Meeting of Stockholders, the Company’s stockholders approved an amendment to, and the Company subsequently amended, its amended and restated certificate of incorporation to extend the indemnification of officers pursuant to recent amendments to the General Corporation Law of the State of Delaware. From time to time, we may receive indemnification claims under existing contracts in the normal course of business. In the event that one or more of these matters were to result in a claim against us, an adverse outcome, including a judgment or settlement, may cause a material adverse effect on our future business, operating results or financial condition. It is not possible to estimate the maximum amount potentially payable under these contracts since we have no history of prior indemnification claims and the unique facts and circumstances involved in each particular claim will be determinative.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2024
Class of Stock Disclosures [Abstract]
Stockholders' Equity	10. Stockholders' Equity Common and Preferred Stock Upon the closing of our IPO in November 2021, we filed an amended and restated certificate of incorporation, which authorized us to issue 300,000,000 shares of common stock and 5,000,000 shares of preferred stock. The shares of preferred stock are currently undesignated. Common stockholders are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings. Common stockholders are entitled to receive dividends, if and when declared by the Company's board of directors (“Board”). No dividends have been declared or paid by us through June 30, 2024. The Private Placement On August 7, 2023, the Company entered into the Purchase Agreement, pursuant to which the Company agreed to sell and issue (i) 37,065,647 shares of the Company’s Common Stock, and (ii) 37,065,647 Warrants in the Private Placement. Each Purchaser’s Warrant is exercisable for a number of shares of Common Stock equal to one hundred percent of the aggregate number of shares of Common Stock purchased by such Purchaser. The Purchase Price for each Common Stock and Warrant was $ 2.025 per share. The Warrants are exercisable at an exercise price of $ 2.47 per share, subject to adjustment as set forth therein. The Warrants are exercisable until the earlier of (i) February 9, 2027, and (ii) one day prior to the closing of an acquisition, as defined in the Warrants. The Warrants may be exercised on a cashless basis if there is no effective registration statement registering the shares underlying the Warrants. The Private Placement closed on August 9, 2023. The Company received $ 75.1 million in gross proceeds from the Private Placement, before deducting offering expenses of $ 3.2 million. Of the total proceeds, legal entities of certain related parties contributed $ 33.4 million, and members of management contributed $ 0.2 million. The Company intends to use the net proceeds of $ 71.9 million from the Private Placement for general corporate purposes. The Warrants were classified as a component of permanent stockholders’ equity within additional paid-in-capital and were recorded at the issuance date using a relative fair value allocation method. The Warrants are equity classified because they are freestanding financial instruments that are legally detachable and separately exercisable from the equity instruments, are immediately exercisable, do not embody an obligation for the Company to repurchase its shares, permit the holders to receive a fixed number of common shares upon exercise, are indexed to the Company’s common stock and meet the equity classification criteria. In addition, such Warrants do not provide any guarantee of value or return. The Company valued the Warrants at issuance using the Black-Scholes valuation model and allocated proceeds from the sale proportionately to the Common Stock and Warrants, of which $ 29.6 million was allocated to the Warrants and recorded as a component of additional paid-in-capital. As of June 30, 2024 , the Company had 37,065,647 warrants issued and outstanding at an exercise price of $ 2.47 per share to purchase shares of the Company's common stock. In connection with the execution of the Purchase Agreement, the Company also entered into a registration rights agreement (the “Registration Rights Agreement”) with the Purchasers. Under the terms of the Registration Rights Agreement, the Company has filed the Registration Statement with the SEC to register for resale the Common Stock issued under the Purchase Agreement and the shares of Common Stock issuable upon conversion of the Warrants issued pursuant to the Purchase Agreement (the “Registrable Securities”), which Registration Statement was declared effective on September 8, 2023. The Company may be required to pay certain liquidated damages under the terms of the Registration Rights Agreement in the event sales cannot be made pursuant to the Registration Statement. As of June 30, 2024 and December 31, 2023, the Company had 65,880,914 common shares outstanding, respectively.

Equity-Based Compensation

Equity-Based Compensation	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Equity-Based Compensation	11. Equity-Based Compensation 2021 Equity and Incentive Plan In November 2021, our Board adopted, and our stockholders approved, the 2021 Equity and Incentive Plan (“2021 Equity Plan”), which became effective on November 4, 2021. The 2021 Equity Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, awards of restricted stock, restricted stock units and other stock-based awards. The number of shares of our common stock reserved for issuance under the 2021 Equity Plan is equal to 2,496,934 , subject to an annual increase, to be added on the first day of each fiscal year, beginning with the fiscal year ending December 31, 2022 and continuing until, and including, the fiscal year ending December 31, 2031, equal to the lesser of (i) 4 % of the number of shares of common stock outstanding on the first day of such fiscal year or (ii) such other amount determined by our Board . As of June 30, 2024, we had 397,992 shares available for future grant under the 2021 Equity Plan. 2021 Employee Stock Purchase Plan In November 2021, our Board adopted and our stockholders approved the 2021 Employee Stock Purchase Plan (“2021 ESPP”), which became effective on November 4, 2021. The number of shares of our common stock reserved for issuance under the 2021 ESPP is equal to 257,272 , subject to an annual increase, to be added on the first day of each fiscal year, beginning January 1, 2023, equal to the lesser of (1) 1 % of the number of shares of common stock outstanding on the first day of such fiscal year; (2) 257,272 shares of our common stock; or (3) such other amount as determined by our Board. As of June 30, 2024, the Board had not yet approved any offerings under the 2021 ESPP. 2023 Inducement Award Plan In September 2023, our Board adopted the 2023 Inducement Award Plan (“2023 Inducement Plan”), which became effective on September 28, 2023. The 2023 Inducement Plan provides for the grant of non-statutory stock options, stock appreciation rights, awards of restricted stock, restricted stock units and other stock-based awards to eligible employees who satisfy the standards for inducement grants under Nasdaq Global Market rules. The number of shares of our common stock reserved for issuance under the 2023 Inducement Plan is equal to 1,976,427 . As of June 30, 2024, there were 1,666,427 shares available for future grant under the 2023 Inducement Plan. The following table summarizes our stock options activity for the six months ended June 30, 2024: Number of Weighted- Weighted- Aggregate Outstanding, January 1, 2024 5,851,923 $ 7.20 8.4 $ 102 Granted 3,325,782 $ 1.60 $ — Cancelled or forfeited ( 185,070 ) $ 3.97 $ — Outstanding, June 30, 2024 8,992,635 $ 5.19 8.6 $ 18 Exercisable, June 30, 2024 3,084,266 $ 8.79 7.6 $ 2 Equity-Based Compensation All share-based awards granted are measured based on the fair value on the date of the grant and compensation expense is recognized with respect to those awards over the requisite service period, which is generally the vesting period of the respective award. Forfeitures related to equity-based compensation awards are recognized as they occur, and we reverse any previously recognized compensation cost associated with forfeited awards in the period the forfeiture occurs. As of June 30, 2024, there was $ 11.7 million of unrecognized compensation cost related to unvested stock-based compensation arrangements that is expected to be recognized over a weighted average period of 3.0 years. The fair values of the stock options granted during the period ended June 30, 2024 were estimated based on the Black-Scholes model, using the following assumptions: Six Months Ended June 30, 2024 Expected volatility 87.0 % - 89.2 % Risk-free interest rate 4.0 % - 4.7 % Expected term (in years) 5.5 - 6.1 Expected dividend yield 0 % Equity-based compensation expense recorded as research and development and general and administrative expenses is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Research and development $ 677 $ 886 $ 1,290 $ 1,590 General and administrative 965 738 1,920 1,922 Total equity-based compensation $ 1,642 $ 1,624 $ 3,210 $ 3,512 We did no t recognize any tax benefits for stock-based compensation during the three and six months ended June 30, 2024 and 2023.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2024
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes We are subject to taxes for earnings generated in multiple jurisdictions, both inside and outside of the United States and our tax expense is primarily affected by unrecognized tax benefits in Denmark due to the full valuation allowance. We recorded expense for income taxes of $ 0.4 million and $ 0.5 million during the three months ended June 30, 2024 and 2023, respectively. We recorded expense for income taxes of $ 0.8 million and $ 0.9 million during the six months ended June 30, 2024 and 2023, respectively. We continue to maintain a full valuation allowance against all of our deferred tax assets in IO Biotech ApS, IO Bio US, Inc., a wholly-owned subsidiary of IO Biotech ApS that was incorporated in Delaware in May 2021, and IO Biotech, Inc. We have evaluated the positive and negative evidence involving our ability to realize our deferred tax assets. We have considered our history of cumulative net losses incurred since inception and our lack of any commercial products. We have concluded that it is more likely than not that we will not realize the benefits of our deferred tax assets in IO Biotech ApS, IO Bio US, Inc. and IO Biotech, Inc. We reevaluate the positive and negative evidence at each reporting period.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Net Loss Per Share	13. Net Loss Per Share Basic and diluted net loss per common share is calculated as follows (in thousands except share and per share amounts): Three Months Ended Six Months Ended 2024 2023 2024 2023 Net loss $ ( 20,686 ) $ ( 21,178 ) $ ( 40,143 ) $ ( 38,222 ) Net loss attributable to common shareholders $ ( 20,686 ) $ ( 21,178 ) $ ( 40,143 ) $ ( 38,222 ) Net loss per common share, basic and diluted $ ( 0.31 ) $ ( 0.74 ) $ ( 0.61 ) $ ( 1.33 ) Weighted-average number of shares used in computing net loss per common share, basic and diluted 65,880,914 28,815,267 65,880,914 28,815,267 The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per common share, as their effect is anti-dilutive: Three Months Ended Six Months Ended 2024 2023 2024 2023 Stock options to purchase common stock 8,992,635 5,470,269 8,992,635 5,470,269 Warrants issued in Private Placement 37,065,647 — 37,065,647 —

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Events We have evaluated subsequent events through the date on which the consolidated financial statements were issued. The Company has concluded that no subsequent events have occurred that require disclosure to the consolidated financial statements.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Unaudited Financial Information	Unaudited Financial Information The accompanying unaudited interim consolidated financial statements included herein have been prepared in conformity with generally accepted accounting principles in the United States of America (“U.S. GAAP”), and pursuant to the rules and regulations of the SEC. In the Company’s opinion, the information furnished herein reflects all adjustments, all of which are of a normal and recurring nature and necessary for a fair presentation of the financial position and results of operations for the reported interim periods. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period. Unaudited interim financial statements and footnotes should be read in conjunction with the audited financial statements and footnotes included in the Company’s Annual Report filed on Form 10-K for the fiscal year ended December 31, 2023 .
Recently Adopted Accounting Standards and Recently Issued Accounting Standards	Recently Adopted Accounting Standards In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity . ASU 2020-06 will simplify the accounting for convertible instruments by reducing the number of accounting models for convertible debt instruments and convertible preferred stock. Limiting the accounting models results in fewer embedded conversion features being separately recognized from the host contract as compared with current U.S. GAAP. Convertible instruments that continue to be subject to separation models are (i) those with embedded conversion features that are not clearly and closely related to the host contract, that meet the definition of a derivative, and that do not qualify for a scope exception from derivative accounting and (ii) convertible debt instruments issued with substantial premiums for which the premiums are recorded as paid-in capital. ASU 2020-06 also amends the guidance for the derivatives scope exception for contracts in an entity’s own equity to reduce form-over-substance-based accounting conclusions. ASU 2020-06 will be effective for us beginning after December 15, 2023. The Company has adopted the standard effective January 1, 2024 . The adoption of the standard has no t had a material impact on our financial statements or financial statement disclosures. Recently Issued Accounting Standards In October 2023, the FASB issued ASU 2023-06, Accounting Standards Update 2023-06—Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. ASU 2023-06 will eliminate disclosure requirements that are redundant, duplicative, overlapping, outdated, or superseded as a result of subsequent changes to SEC disclosure requirements, U.S. GAAP or technology. ASU 2023-06 is intended to better align U.S. GAAP requirements with those of the SEC and to facilitate the application of U.S. GAAP. The disclosure requirements would apply prospectively in the financial statements. ASU 2023-06 will be effective for us on the date on which the SEC’s removal of that related disclosure requirement from Regulation S-X or Regulation S-K becomes effective, if we are already subject to the SEC’s current disclosure requirements. For those current disclosure requirements we are not subject to, ASU 2023-06 will become effective two years after the date of such removal by the SEC. We are currently assessing the impact adoption of ASU 2023-06 will have on our financial statements and disclosures. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. ASU 2023-07 will improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. ASU 2023-07 will also enhance interim disclosure requirements, clarify circumstances in which an entity can disclose multiple segment measures of profit or loss, provide new segment disclosure requirements for entities with a single reportable segment and contain other disclosure requirements. The enhanced segment disclosure requirements apply retrospectively to all prior periods presented in the financial statements. ASU 2023-07 will be effective for us in the annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We are currently assessing the impact adoption of ASU 2023-07 will have on our financial statements and disclosures, but do not expect a material impact on the financial statements or disclosures. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. ASU 2023-09 will require disclosure of additional information in specified categories with respect to the reconciliation of the effective tax rate to the statutory rate (the rate reconciliation) for federal, state and foreign income taxes. ASU 2023-09 will also require information pertaining to taxes paid (net of refunds received) to be disaggregated for federal, state and foreign taxes and further disaggregated for specific jurisdictions to the extent the related amounts exceed a quantitative threshold. ASU 2023-09 will be effective for us in the annual periods beginning after December 15, 2024. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. We are currently assessing the impact adoption of ASU 2023-09 will have on our financial statements and disclosures. Other than the items noted above, there have been no new accounting pronouncements not yet effective or adopted in the current year that we believe have a significant impact, or potential significant impact, to our unaudited interim consolidated financial statements.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Summary of Assets Measured at Fair Value	The following table presents information about our financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): June 30, 2024 Total Level 1 Level 2 Level 3 Assets Money market funds (1) $ 76,066 $ 76,066 $ — $ — Total assets measured at fair value $ 76,066 $ 76,066 $ — $ — December 31, 2023 Total Level 1 Level 2 Level 3 Assets Money market funds (1) $ 131,613 $ 131,613 $ — $ — Total assets measured at fair value $ 131,613 $ 131,613 $ — $ — (1) Money market funds with maturities of 90 days or less at the date of purchase are included within cash and cash equivalents in the accompanying consolidated balance sheets and are recognized at fair value.

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	6 Months Ended
	Jun. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Summary of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consist of the following (in thousands): June 30, December 31, Prepaid contract research and development costs $ 3,239 $ — Prepaid income taxes 1,211 829 Research and development tax credit receivable 791 814 Insurance 651 1,352 Value-added tax refund receivable 239 313 Other 774 754 Total prepaid expenses and other current assets $ 6,905 $ 4,062

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consist of the following (in thousands): June 30, December 31, Laboratory equipment $ 829 $ 836 Office furniture 235 238 Computer hardware 128 103 Less: accumulated depreciation ( 457 ) ( 330 ) Total property and equipment, net $ 735 $ 847

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2024
Payables and Accruals [Abstract]
Summary of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consist of the following (in thousands): June 30, December 31, Accrued contract research and development costs $ 4,385 $ 6,153 Employee compensation costs 2,520 4,225 Professional fees 585 243 Other liabilities 539 563 Total accrued expenses and other current liabilities $ 8,029 $ 11,184

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2024
Leases [Abstract]
Schedule of Quantitative Information Regarding Leases	Quantitative information regarding the Company’s leases for the six months ended June 30, 2024 and 2023 is as follows (in thousands): Six Months Ended Six Months Ended Lease Cost June 30, 2024 June 30, 2023 Operating lease cost $ 369 $ 351 Operating cash flows paid for amounts included in the measurement of lease liabilities $ 385 $ 353 Operating lease liabilities arising from obtaining right-of-use assets $ — $ 235 Remaining average lease term (years) 3.0 4.0 Weighted average discount rate 6.3 % 6.3 %
Schedule of Future Lease Payments (Undiscounted) under Noncancelable Leases	Future lease payments (undiscounted) under noncancelable leases are as follows at June 30, 2024 (in thousands): Future Lease Payments Amount Remainder of 2024 $ 394 2025 785 2026 791 2027 395 2028 — Thereafter — Total $ 2,365

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Schedule of Stock Options Activity	The following table summarizes our stock options activity for the six months ended June 30, 2024: Number of Weighted- Weighted- Aggregate Outstanding, January 1, 2024 5,851,923 $ 7.20 8.4 $ 102 Granted 3,325,782 $ 1.60 $ — Cancelled or forfeited ( 185,070 ) $ 3.97 $ — Outstanding, June 30, 2024 8,992,635 $ 5.19 8.6 $ 18 Exercisable, June 30, 2024 3,084,266 $ 8.79 7.6 $ 2
Summary of Assumptions for Estimated Fair Value of Options	The fair values of the stock options granted during the period ended June 30, 2024 were estimated based on the Black-Scholes model, using the following assumptions: Six Months Ended June 30, 2024 Expected volatility 87.0 % - 89.2 % Risk-free interest rate 4.0 % - 4.7 % Expected term (in years) 5.5 - 6.1 Expected dividend yield 0 %
Schedule of Equity-based Compensation Expense	Equity-based compensation expense recorded as research and development and general and administrative expenses is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Research and development $ 677 $ 886 $ 1,290 $ 1,590 General and administrative 965 738 1,920 1,922 Total equity-based compensation $ 1,642 $ 1,624 $ 3,210 $ 3,512

Net Loss Per Share (Table)

Net Loss Per Share (Table)	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Basic and diluted net loss per common share is calculated as follows (in thousands except share and per share amounts): Three Months Ended Six Months Ended 2024 2023 2024 2023 Net loss $ ( 20,686 ) $ ( 21,178 ) $ ( 40,143 ) $ ( 38,222 ) Net loss attributable to common shareholders $ ( 20,686 ) $ ( 21,178 ) $ ( 40,143 ) $ ( 38,222 ) Net loss per common share, basic and diluted $ ( 0.31 ) $ ( 0.74 ) $ ( 0.61 ) $ ( 1.33 ) Weighted-average number of shares used in computing net loss per common share, basic and diluted 65,880,914 28,815,267 65,880,914 28,815,267
Schedule of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share	The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per common share, as their effect is anti-dilutive: Three Months Ended Six Months Ended 2024 2023 2024 2023 Stock options to purchase common stock 8,992,635 5,470,269 8,992,635 5,470,269 Warrants issued in Private Placement 37,065,647 — 37,065,647 —

Description of Business, Orga_2

Description of Business, Organization and Liquidity - Additional Information (Details) - USD ($)		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Aug. 09, 2023	Nov. 30, 2021	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Feb. 15, 2023	Nov. 09, 2021
Description Of Business Organization And Liquidity [Line Items]
Common stock, par value			$ 0.001		$ 0.001		$ 0.001
Accumulated deficit			$ (303,965,000)		$ (303,965,000)		$ (263,822,000)
Net losses			(20,686,000)	$ (21,178,000)	(40,143,000)	$ (38,222,000)	(86,100,000)
Cash and cash equivalents			$ 100,747,000	$ 110,095,000	$ 100,747,000	$ 110,095,000	$ 143,193,000
Net proceeds from IPO, after deducting underwriting discounts, commissions and offering costs		$ 103,300,000
Convertible preference share issued upon conversion									20,592,413
Common stock shares issued			65,880,914		65,880,914		65,880,914		28,815,267
Common stock shares outstanding			65,880,914		65,880,914		65,880,914		28,815,267
Common stock shares authorized			300,000,000		300,000,000		300,000,000		300,000,000
Preferred stock shares authorized			5,000,000		5,000,000		5,000,000
Proceeds from private placement	$ 71,900,000
Class A Ordinary Shares
Description Of Business Organization And Liquidity [Line Items]
Common stock, par value		$ 0.16
Common stock conversion basis		one-for-one
Class B Preference Shares
Description Of Business Organization And Liquidity [Line Items]
Common stock, par value		$ 0.001
Common stock conversion basis		one-for-one
Class C Preference Shares
Description Of Business Organization And Liquidity [Line Items]
Common stock, par value		$ 0.001
Common stock conversion basis		one-for-one
Undesignated Preferred Stock
Description Of Business Organization And Liquidity [Line Items]
Preferred stock shares authorized									5,000,000
Underwriters
Description Of Business Organization And Liquidity [Line Items]
Shares issued		1,072,500
IPO
Description Of Business Organization And Liquidity [Line Items]
Shares issued		8,222,500
Common stock shares sold, price per share		$ 14
At-The-Market Equity Program
Description Of Business Organization And Liquidity [Line Items]
Shares issued					0
Common stock, maximum aggregate offering price								$ 19,500,000
At-The-Market Equity Program | Sales Agreement
Description Of Business Organization And Liquidity [Line Items]
Common stock, maximum aggregate offering price								$ 75,000,000
Private Placement
Description Of Business Organization And Liquidity [Line Items]
Common stock, par value	$ 0.001
Shares issued	37,065,647
Warrants Issued	37,065,647
Purchase price per share of common stock and warrant	$ 2.025
Offering expenses	$ 3,200,000
Private Placement | Maximum | Common Stock
Description Of Business Organization And Liquidity [Line Items]
Shares issued	37,065,647

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Details)	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2024
Change in accounting principle, accounting standards update, immaterial effect [true false]	true
Accounting standards update [extensible enumeration]	us-gaap:AccountingStandardsUpdate202006Member

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Assets Measured at Fair Value (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Assets
Total assets measured at fair value	$ 76,066	$ 131,613
Money Market Funds
Assets
Total assets measured at fair value	76,066	131,613
Level 1
Assets
Total assets measured at fair value	76,066	131,613
Level 1 | Money Market Funds
Assets
Total assets measured at fair value	$ 76,066	$ 131,613

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount	$ 0	$ 0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	$ 0	$ 0

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid contract research and development costs	$ 3,239
Prepaid income taxes	1,211	$ 829
Research and development tax credit receivable	791	814
Insurance	651	1,352
Value-added tax refund receivable	239	313
Other	774	754
Total prepaid expenses and other current assets	$ 6,905	$ 4,062

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation	$ (457)	$ (330)
Total property and equipment, net	735	847
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	829	836
Office furniture
Property, Plant and Equipment [Line Items]
Property and equipment, gross	235	238
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 128	$ 103

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 0.1	$ 0.1	$ 0.1	$ 0.1

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued contract research and development costs	$ 4,385	$ 6,153
Employee compensation costs	2,520	4,225
Professional fees	585	243
Other liabilities	539	563
Total accrued expenses and other current liabilities	$ 8,029	$ 11,184

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2024 USD ($) Lease	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Lessee, Lease, Description [Line Items]
Rent expense	$ 200	$ 400	$ 400
Number of operating leases | Lease		5
Right of use lease asset	1,936	$ 1,936		$ 2,259
Operating lease liability, current	678	678		655
Operating lease, liability, non-current	$ 1,472	1,472		$ 1,839
Office and Laboratory | Denmark
Lessee, Lease, Description [Line Items]
Operating lease amended base rent		200
Office and Laboratory | New York, NY
Lessee, Lease, Description [Line Items]
Operating lease annual base rent		200
Office and Laboratory | Maryland
Lessee, Lease, Description [Line Items]
Operating lease annual base rent		300
Office | Denmark
Lessee, Lease, Description [Line Items]
Operating lease annual base rent		100
Laboratory | Denmark
Lessee, Lease, Description [Line Items]
Operating lease annual base rent		$ 40

Leases - Schedule of Quantitati

Leases - Schedule of Quantitative information Regarding Leases (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 369	$ 351
Operating cash flows paid for amounts included in the measurement of lease liabilities	385	353
Operating lease liabilities arising from obtaining right-of-use assets	$ 0	$ 235
Remaining average lease term (years)	3 years	4 years
Weighted average discount rate	6.30%	6.30%

Leases - Schedule of Future Lea

Leases - Schedule of Future Lease Payments (Undiscounted) under Noncancelable Leases (Details) $ in Thousands	Jun. 30, 2024 USD ($)
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
Remainder of 2024	$ 394
2025	785
2026	791
2027	395
2028	0
Thereafter	0
Total	$ 2,365

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	6 Months Ended
	Jun. 30, 2024
Minimum
Other Commitments [Line Items]
Contractual obligations termination notice period	30 days
Maximum
Other Commitments [Line Items]
Contractual obligations termination notice period	90 days

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details)			6 Months Ended
	Aug. 09, 2023 USD ($) $ / shares shares	Aug. 07, 2023 $ / shares shares	Jun. 30, 2024 USD ($) Vote $ / shares shares	Dec. 31, 2023 shares	Nov. 09, 2021 shares
Subsidiary, Sale of Stock [Line Items]
Common stock shares authorized | shares			300,000,000	300,000,000	300,000,000
Preferred stock, shares authorized | shares			5,000,000	5,000,000
Number of votes per share | Vote			1
Common stock shares outstanding | shares			65,880,914	65,880,914	28,815,267
Proceeds from private placement	$ 71,900,000
Private Placement
Subsidiary, Sale of Stock [Line Items]
Shares issued | shares	37,065,647
Warrants issued | shares	37,065,647
Purchase price per share of common stock and warrant | $ / shares	$ 2.025
Offering expenses	$ 3,200,000
Private Placement | Securities Purchase Agreement
Subsidiary, Sale of Stock [Line Items]
Warrants issued | shares		37,065,647	37,065,647
Purchase price per share of common stock and warrant | $ / shares		$ 2.025
Proceeds from private placement	75,100,000
Purchase Price of Common Stock and Warrants | $ / shares		$ 2.47	$ 2.47
Net Proceeds From Issuance Of Private Placement	71,900,000
Offering expenses	3,200,000
Proceeds from Issuance of Warrants			$ 29,600,000
Private Placement | Securities Purchase Agreement | Management
Subsidiary, Sale of Stock [Line Items]
Proceeds from private placement	200,000
Private Placement | Securities Purchase Agreement | Related Party
Subsidiary, Sale of Stock [Line Items]
Proceeds from private placement	$ 33,400,000
Common Stock | Private Placement | Securities Purchase Agreement
Subsidiary, Sale of Stock [Line Items]
Shares issued | shares		37,065,647
Undesignated Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Preferred stock, shares authorized | shares					5,000,000
Dividend Declared
Subsidiary, Sale of Stock [Line Items]
Dividends			0
Dividend Paid
Subsidiary, Sale of Stock [Line Items]
Dividends			$ 0

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Details) - USD ($)		6 Months Ended
	Nov. 04, 2021	Jun. 30, 2024	Jun. 30, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost		$ 11,700,000
Unrecognized compensation cost, recognition period		3 years
Tax benefits for stock-based compensation		$ 0	$ 0
2021 Equity and Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of warrants available for future grant		397,992
Common stock reserved for issuance	2,496,934
Maximum percentage of shares that may be issued under the plan as a proportion of outstanding capital stock	4%
2021 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance	257,272
2021 Employee Stock Purchase Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum percentage of shares that may be issued under the plan as a proportion of outstanding capital stock	1%
2023 Inducement Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of warrants available for future grant		1,666,427
Common stock reserved for issuance		1,976,427

Equity-Based Compensation - Sch

Equity-Based Compensation - Schedule of Stock Options Activity (Details) - Warrant - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Warrants, Beginning balance	5,851,923
Number of Warrants, Granted	3,325,782
Number of Warrants, Cancelled or forfeited	(185,070)
Number of Warrants, Ending balance	8,992,635	5,851,923
Number of Warrants, Exercisable	3,084,266
Weighted-average exercise price per share, Beginning balance	$ 7.2
Weighted-average exercise price per share, Granted	1.6
Weighted-average exercise price per share, Cancelled or forfeited	3.97
Weighted-average exercise price per share, Ending balance	5.19	$ 7.2
Weighted-average exercise price per share, Exercisable	$ 8.79
Weighted-average remaining contractual term (in years), Outstanding	8 years 7 months 6 days	8 years 4 months 24 days
Weighted-average remaining contractual term (in years), Exercisable	7 years 7 months 6 days
Aggregate intrinsic value, Outstanding	$ 18	$ 102
Aggregate intrinsic value, Exercisable	$ 2

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Assumptions for Estimated Fair Value of Options (Details)	6 Months Ended
	Jun. 30, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected volatility minimum	87%
Expected volatility maximum	89.20%
Risk-free interest rate minimum	4%
Risk-free interest rate maximum	4.70%
Expected dividend yield	0%
Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (in years)	5 years 6 months
Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (in years)	6 years 1 month 6 days

Equity-Based Compensation - S_2

Equity-Based Compensation - Schedule of Equity-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total equity-based compensation	$ 1,642	$ 1,624	$ 3,210	$ 3,512
Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total equity-based compensation	677	886	1,290	1,590
General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total equity-based compensation	$ 965	$ 738	$ 1,920	$ 1,922

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income taxes expense	$ 374	$ 532	$ 789	$ 938

Net Loss Per Share - Basic and

Net Loss Per Share - Basic and Diluted Net Loss Per Ordinary Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Earnings Per Share [Abstract]
Net loss	$ (20,686)	$ (21,178)	$ (40,143)	$ (38,222)	$ (86,100)
Net loss attributable to common shareholders	$ (20,686)	$ (21,178)	$ (40,143)	$ (38,222)
Net loss per common share, basic	$ (0.31)	$ (0.74)	$ (0.61)	$ (1.33)
Net loss per common share, diluted	$ (0.31)	$ (0.74)	$ (0.61)	$ (1.33)
Weighted-average number of shares used in computing net loss per common share, basic	65,880,914	28,815,267	65,880,914	28,815,267
Weighted-average number of shares used in computing net loss per common share, diluted	65,880,914	28,815,267	65,880,914	28,815,267

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Stock Options to Purchase Common Stock
Earnings Per Share Basic [Line Items]
Outstanding potentially dilutive securities	8,992,635	5,470,269	8,992,635	5,470,269
Warrants Issued in Private Placement
Earnings Per Share Basic [Line Items]
Outstanding potentially dilutive securities	37,065,647		37,065,647