0001193125-26-234386 | 10-Q | XBRL Viewer | Hemab Therapeutics Holdings INC

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Equity-Based Compensation - Summary of The Company's Warrants (Details) - Warrant [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Warrants Outstanding, Beginning	2,101,352
Number of Warrants, Granted	2,294,798
Number of Warrants, Forfeited	(23,408)
Number of Warrants Outstanding, Ending	4,372,742	2,101,352
Number of Warrants, Exercisable	1,568,666
Number of Warrants, Vested and expected to vest	4,372,742
Weighted- average exercise price per share Outstanding, Beginning	$ 5.68
Weighted- average exercise price per share, Granted	6
Weighted- average exercise price per share, Forfeited	6.97
Weighted- average exercise price per share Outstanding, Ending	5.84	$ 5.68
Weighted- average exercise price per share, Exercisable	5.12
Weighted- average exercise price per share, Vested and expected to vest	$ 5.84
Weighted- average remaining contractual term (in years), Outstanding	8 years 7 months 6 days	7 years 4 months 24 days
Weighted- average remaining contractual term (in years), Exercisable	6 years 10 months 24 days
Weighted- average remaining contractual term (in years), Vested and expected to vest	8 years 7 months 6 days
Aggregate intrinsic value (in thousands), Outstanding, Beginning	$ 2,409
Aggregate intrinsic value (in thousands), Granted	0
Aggregate intrinsic value (in thousands), Forfeited	0
Aggregate intrinsic value (in thousands), Outstanding, Ending	28,045	$ 2,409
Aggregate intrinsic value (in thousands), Exercisable	11,141
Aggregate intrinsic value (in thousands), Vested and expected to vest	$ 28,045

Description of Business and Liquidity	3 Months Ended
Description of Business and Liquidity	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Liquidity	1. Description of Business and Liquidity Nature of Business Hemab Therapeutics Holdings, Inc. (the “Company”) is a clinical-stage biotechnology company developing therapies that reimagine the treatment of blood coagulation disorders to sustain life and human resilience. Based in Denmark and the United States, the Company’s mission is to build the leading coagulation company by discovering, developing, and commercializing innovative therapies for the millions of patients worldwide suffering from serious bleeding and thrombotic diseases, including Glanzmann thrombasthenia, Factor VII deficiency, Von Willebrand Disease and other conditions of abnormal bleeding, all of which can cause significant life-long burden to patients. The Company’s lead asset, sutacimig (HMB-001), is a bispecific antibody currently in Phase 1/2 clinical development for the prophylactic treatment of Glanzmann thrombasthenia and Phase 2 clinical development for the prophylactic treatment of Factor VII deficiency. The Company’s second clinical-stage asset, HMB-002, is a monovalent antibody in Phase 1/2 clinical development for the subcutaneous prophylactic treatment of Von Willebrand Disease. The Company is also advancing multiple preclinical and discovery-stage assets. Corporate Reorganization On March 30, 2026, the Company completed a corporate reorganization pursuant to which the shareholders of Hemab ApS exchanged their shares in Hemab ApS for the same number, class and series of newly issued shares, on a one to one basis, in the newly incorporated Delaware company, Hemab Therapeutics Holdings, Inc. and, as a result, Hemab ApS became a wholly owned subsidiary of Hemab Therapeutics Holdings, Inc. The newly issued shares of Hemab Therapeutics Holdings, Inc. had substantially identical rights to the exchanged shares of Hemab ApS. As a result of the exchange, Hemab Therapeutics Holdings, Inc. became the sole shareholder of Hemab ApS, and the prior shareholders of Hemab ApS solely held shares of Hemab Therapeutics Holdings, Inc. Hemab Therapeutics Holdings, Inc. had nominal assets and liabilities and did not conduct any operations prior to the corporate reorganization other than its incorporation. Upon completion of the corporate reorganization, the historical consolidated financial statements of Hemab ApS became the historical consolidated financial statements of Hemab Therapeutics Holdings, Inc. In connection with the corporate reorganization, the original issue price for the Company’s Series Seed Convertible Stock and Series A Convertible Stock were converted from Euros and Danish Kroners (“DKK”), respectively, into U.S. dollars.The original issue price was set for each series of convertible preferred stock so the convertible preferred stock would be convertible into common stock on a one-for-one basis. In connection with the corporate reorganization, each outstanding warrant to subscribe for the purchase of ordinary shares of Hemab ApS was assumed by Hemab Therapeutics Holdings, Inc. and converted into a warrant to purchase the same number of shares of common stock of Hemab Therapeutics Holdings, Inc. Each new warrant otherwise had and was subject to the same terms and conditions as were in effect immediately prior to the assumption and conversion, except that any warrant exercise price that had been denominated in DKK prior to the corporate reorganization was converted into an exercise price in U.S. dollars at the exchange rate as in effect at the close of business on the business day prior to the corporate reorganization. No warrants of Hemab ApS were outstanding following such assumption and conversion. Additionally, on April 1, 2026, Hemab ApS transferred its shares of Hemab Therapeutics Inc., a Delaware corporation and wholly owned subsidiary of Hemab ApS, to Hemab Therapeutics Holdings, Inc. in exchange for the issuance of a promissory note and, as a result, Hemab Therapeutics Inc. became a wholly owned subsidiary of Hemab Therapeutics Holdings, Inc. Risks and Uncertainties The Company is 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. The Company’s product candidates and programs are in preclinical and clinical development. There can be no assurance that the Company’s research and development efforts will be successfully completed, that adequate protection for its intellectual property will be obtained, that any product candidates developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees and consultants. Stock Split The Company’s board of directors and stockholders approved a 22-for-one forward stock split of the Company’s issued and outstanding common stock and a proportional adjustment to the existing conversion ratios for the outstanding shares of convertible preferred stock, which became effective on April 24, 2026. Accordingly, all share and per share amounts for all periods presented in the accompanying condensed consolidated financial statements and the notes thereto have been retroactively adjusted, where applicable, to reflect the stock split. Liquidity and Managements Plan Since inception, the Company has devoted substantially all its efforts to business planning, conducting research and development, recruiting management and technical staff, and raising capital. The Company has financed its operations primarily through private placements of convertible preference shares and issuance of convertible debt and, most recently, from the sale of common stock in its initial public offering (the “IPO”) in May 2026. The Company’s 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, infrastructure, and compliance-reporting capabilities. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company has incurred losses since inception and had an accumulated deficit of $204.5 million as of March 31, 2026. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future as it continues development of its product candidates. As of March 31, 2026, the Company had cash and cash equivalents, and marketable securities of $163.5 million. The Company believes that its existing cash, cash equivalents, and marketable securities, together with the net proceeds from the IPO of approximately $317.2 million, will enable it to fund its operating expenses and capital expenditure requirements for at least one year from the date of the issuance of these unaudited condensed consolidated financial statements. Until such a time when the Company can generate significant revenue from product sales, if ever, the Company expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances, and marketing, distribution or licensing arrangements. The Company may be unable to raise additional funds or enter into such other agreements or arrangements when needed, on favorable terms, or at all. The Company’s failure to raise capital or enter into such agreements or arrangements as, and when needed, could have a material adverse effect on its business, results of operations and financial condition, including potentially requiring it to delay, limit, reduce or eliminate product development or future commercialization efforts, or grant rights to develop and market current or future development product candidates that the Company would otherwise prefer to develop and market itself.

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2026
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Equity-Based Compensation - Summary of Equity-based Compensation Expense Recorded As Research And Development And General and Administrative Expenses (Details) - Warrant [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Equity-based compensation expense	$ 1,318	$ 459
Research and development [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Equity-based compensation expense	565	180
General and administrative [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Equity-based compensation expense	$ 753	$ 279

Property and Equipment, net

3 Months Ended

Mar. 31, 2026

Property, Plant and Equipment [Abstract]

Property and Equipment, net

6. Property and Equipment, net

Property and equipment, net, consisted of the following (in thousands):


	As of March 31, 2026			As of December 31, 2025
Laboratory equipment	$	887		$	775
Furniture and fixtures		413			413
Leasehold improvements		82			82
Computer equipment		62			62

Total property and equipment, at cost		1,444			1,332
Less: accumulated depreciation		(796	)		(723	)

Property and equipment, net	$	648		$	609

As of March 31, 2026, there were no finance leased assets included in property and equipment, net. As of December 31, 2025, property and equipment, net included finance leased assets of approximately $0.5 million, with accumulated depreciation of approximately $0.3 million. Depreciation expense for the three months ended March 31, 2026 and 2025 was approximately $0.1 million.

Available-For-Sale Debt Securities (Tables)

3 Months Ended

Mar. 31, 2026

Investments, Debt and Equity Securities [Abstract]

Summary of Available For Sale Debt Securities

Available-for-sale debt

securities consisted of the following as of March 31, 2026 and December 31, 2025 (in thousands):


	March 31, 2026
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Marketable securities:
U.S. treasury securities	$	98,393	$	—	$	(112	)	$	98,281
Non-U.S. debt securities		15,717		—		(327	)		15,390

Total	$	114,110	$	—	$	(439	)	$	113,671


	December 31, 2025
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Non-U.S. debt securities	$	17,415	$	223	$	—		$	17,638
Marketable securities:
U.S. treasury securities		97,559		—		(48	)		97,511

Total	$	114,974	$	223	$	(48	)	$	115,149

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

Equity-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Summary of Assumptions Used For Determining The Fair Value of Warrants Granted

The following assumptions were used in determining the fair value of warrants granted during the three months ended March 31, 2026:


		Three Months Ended March 31, 2026
Expected volatility		89.1% - 91.2%
Risk-free interest rate		3.8% - 3.9%
Expected term (in years)		5.8 - 6.2
Expected dividend yield		0%
Fair value per share		$9.37

Summary of The Company's Warrants

The following table summarizes the Company’s warrants for the three months ended March 31, 2026:


	Number of Warrants			Weighted- average exercise price per share		Weighted- average remaining contractual term (in years)		Aggregate intrinsic value (in thousands)
Outstanding, December 31, 2025		2,101,352		$	5.68		7.4	$	2,409
Granted		2,294,798		$	6.00		—	$	—
Forfeited		(23,408	)	$	6.97		—	$	—

Outstanding, March 31, 2026		4,372,742		$	5.84		8.6	$	28,045

Exercisable at March 31, 2026		1,568,666		$	5.12		6.9	$	11,141

Vested and expected to vest, March 31, 2026		4,372,742		$	5.84		8.6	$	28,045

Summary of Equity-based Compensation Expense Recorded As Research And Development And General and Administrative Expenses

Equity-based compensation expense recorded as research and development and general and administrative expenses is as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Research and development	$	565	$	180
General and administrative		753		279

Total	$	1,318	$	459

Convertible Preferred Stock And Convertible Preference Shares - Summary of Convertible Preferred Stock And Convertible Preference Shares (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Jul. 31, 2021
Schedule Of Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred Stock Authorized	1,204,405	1,204,405
Preferred stock issued and outstanding	1,204,405	1,204,405
Carrying Value	$ 360,068	$ 360,068
Liquidation Preference	$ 348,664	$ 349,613
Common Stock Issuable Upon Conversion	26,496,910	26,496,910
Series Seed Convertible Preference Shares [Member]
Schedule Of Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred Stock Authorized	23,343	23,343
Preferred stock issued and outstanding	23,343	23,343
Carrying Value	$ 5,236	$ 5,236
Liquidation Preference	$ 3,126	$ 2,939
Common Stock Issuable Upon Conversion	513,546	513,546
Series A Convertible Preference Shares [Member]
Schedule Of Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred Stock Authorized	225,866	225,866
Preferred stock issued and outstanding	225,866	225,866	37,297
Carrying Value	$ 63,536	$ 63,536
Liquidation Preference	$ 53,392	$ 54,528
Common Stock Issuable Upon Conversion	4,969,052	4,969,052	24,303
Series B Convertible Preference Shares [Member]
Schedule Of Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred Stock Authorized	442,205	442,205
Preferred stock issued and outstanding	442,205	442,205
Carrying Value	$ 134,975	$ 134,975
Liquidation Preference	$ 135,248	$ 135,248
Common Stock Issuable Upon Conversion	9,728,510	9,728,510
Series C Convertible Preference Shares [Member]
Schedule Of Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred Stock Authorized	512,991	512,991
Preferred stock issued and outstanding	512,991	512,991
Carrying Value	$ 156,421	$ 156,421
Liquidation Preference	$ 156,898	$ 156,898
Common Stock Issuable Upon Conversion	11,285,802	11,285,802

Fair Value Measurements - Summary of Fair Value Assets And Liabilities Measured On Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 113,671	$ 166,079
Quoted Prices in Active Markets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	0	0
Significant Observable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	113,671	166,079
Significant Unobservable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	0	0
U.S. treasury securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	98,281	97,511
U.S. treasury securities [Member] \| Quoted Prices in Active Markets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	0
U.S. treasury securities [Member] \| Significant Observable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	98,281	97,511
U.S. treasury securities [Member] \| Significant Unobservable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	0
Non-U.S. debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	15,390
Cash and Cash Equivalents, Fair Value Disclosure		17,638
Non-U.S. debt securities [Member] \| Quoted Prices in Active Markets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0
Cash and Cash Equivalents, Fair Value Disclosure		0
Non-U.S. debt securities [Member] \| Significant Observable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	15,390
Cash and Cash Equivalents, Fair Value Disclosure		17,638
Non-U.S. debt securities [Member] \| Significant Unobservable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	$ 0
Cash and Cash Equivalents, Fair Value Disclosure		0
Certificates of deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		50,930
Certificates of deposit [Member] \| Quoted Prices in Active Markets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		0
Certificates of deposit [Member] \| Significant Observable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		50,930
Certificates of deposit [Member] \| Significant Unobservable Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure		$ 0

Property and Equipment, net - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Property, Plant and Equipment [Abstract]
Finance leased assets	$ 0.0		$ 0.5
Accumulated depreciation	0.3
Depreciation on property plant and equipment	$ 0.1	$ 0.1

Available-For-Sale Debt Securities - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Held To Maturity Securities Debt Maturities	12 months
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 113,700,000	$ 97,500,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 0

Available-For-Sale Debt Securities - Summary of Available For Sale Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 114,110	$ 114,974
Unrealized Gains	0	223
Unrealized Losses	(439)	(48)
Fair Value	113,671	115,149
Non-U.S. debt securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	15,717	17,415
Unrealized Gains	0	223
Unrealized Losses	(327)	0
Fair Value	15,390	17,638
US Treasury Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	98,393	97,559
Unrealized Gains	0	0
Unrealized Losses	(112)	(48)
Fair Value	$ 98,281	$ 97,511

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (d)
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2026
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies There have been no significant changes from the significant accounting policies and estimates disclosed in Note 2 of the “Notes to Consolidated Financial Statements” in the audited consolidated financial statements for the year ended December 31, 2025 and notes thereto, included in the Company’s final prospectus filed pursuant to Rule 424(b)(4) under the Securities Act of 1933, as amended, with the U.S. Securities Exchange Commission on May 1, 2026, except as noted below. Principles of Consolidation The Company’s condensed consolidated financial statements include the accounts of its subsidiaries, Hemab ApS and Hemab Therapeutics, Inc., which was a wholly owned subsidiary of Hemab ApS until April 1, 2026. As a result of the corporate reorganization described in Note 1 “Description of Business and Liquidity—Corporate Reorganization”, Hemab ApS became a wholly owned subsidiary of Hemab Therapeutics Holdings, Inc. and, accordingly, the Company’s consolidated financial statements are those of Hemab Therapeutics Holdings, Inc. for the periods after the corporate reorganization and are those of Hemab ApS for historical periods before the corporate reorganization. Management has concluded the Company has a single reporting segment for purposes of reporting financial condition and results of operations. All intercompany transactions and balances have been eliminated in accordance with ASC 810, Consolidation . Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). Unaudited Interim Consolidated Financial Information The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements of Hemab ApS and reflect, in the opinion of management, all adjustments of a normal and recurring nature that are necessary for the fair statement of the Company’s financial position as of March 31, 2026 and its results of operations and cash flows for the three months ended March 31, 2026 and 2025. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, or for any other future annual or interim period. The condensed consolidated balance sheet as of December 31, 2025 included herein was derived from the audited financial statements of Hemab ApS as of that date. Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with GAAP have been condensed or omitted from these unaudited condensed consolidated financial statements. Foreign Currency The financial statements are presented in U.S. dollars, the Company’s reporting currency. The functional currency of Hemab ApS and Hemab Therapeutics, Inc. is the U.S. dollar. Transaction gains and losses resulting from exchange rate changes on transactions denominated in currencies other than the U.S. dollar are recognized in other (expense) income, net in the consolidated statements of operations and comprehensive loss. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and in these accompanying notes. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors and assumptions that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates, which include, but are not limited to, accrued research and development expenses, the fair value of the ordinary shares and warrants for equity-based compensation expense, and the valuation of the Company’s deferred tax assets. Changes in estimates are recorded in the period in which they become known. Concentrations of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk primarily consist of cash, cash equivalents, and marketable securities. The Company’s investment portfolio is primarily comprised of short term debt securities issued by the U.S., Danish, and German governments. The Company places its cash in financial institutions that management believes to be of high credit quality and, consequently, the Company does not believe it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Bank accounts in the United States are insured by the Federal Deposit Insurance Corporation up to $250,000. Deferred Offering Costs Deferred offering costs consist of certain legal, professional, accounting and other third-party fees that are directly associated with the IPO. These direct costs are capitalized and recorded as other non-current assets on the condensed consolidated balance sheets. The deferred offering costs will be recorded against the IPO proceeds upon the consummation of the IPO, which was completed on May 4, 2026. As of March 31, 2026, the Company had $2.7 million of deferred offering costs. Comprehensive Loss Comprehensive loss includes net loss as well as other changes in stockholders’ deficit that result from transactions and events other than those with stockholders. The Company’s unrealized gains and losses on available-for sale-debt securities represent the only component of other comprehensive income (loss). Recently Issued Accounting Standards In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). 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 the Company in the annual periods beginning after December 15, 2025. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. The Company is currently assessing the impact adoption of ASU 2023-09 will have on its consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”). ASU 2024-03 will require disclosure of disaggregated information about certain income statement expense line items on an annual and interim basis, including purchases of inventory, employee compensation, depreciation, intangible asset amortization and depletion for each income statement line item that contains those expenses. ASU 2024-03 also will require certain amounts already disclosed under existing U.S. GAAP to also be disclosed as a separate category in disaggregated expense table(s), if those amounts are recognized in the relevant expense line item. The amendments in ASU 2024-03 will be effective for the Company in annual reporting periods beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027. The Company is currently assessing the impact adoption of ASU 2024-03 will have on its consolidated financial statements and related disclosures. In December 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements (“ASU 2025-11”) to provide clarifications intended to improve the consistency and usability of interim disclosure requirements. ASU 2025-11 includes a comprehensive listing of required interim disclosures and a new disclosure principle for reporting material events occurring after the most recent annual period. ASU 2025-11 is effective for interim periods within annual reporting periods beginning after December 15, 2027, and early adoption is permitted. The amendments in this update permit an entity to apply the new guidance using a prospective or retrospective approach. The Company is currently assessing the impact adoption of ASU 2025-11 will have on its consolidated financial statements and related disclosures.

Segment Reporting (Tables)

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Summary of Long-Lived Assets By Geographic Location

The following table presents long-lived assets by geographic location as of March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
	2026		2025
United States of America	$	348	$	786
Denmark		1,239		1,582

	$	1,587	$	2,368

Summary of Reconciliation of Operating Profit (Loss) from Segments to Consolidated

The following table presents selected financial information about the Company’s single operating segment for the three months ended March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
	2026			2025
Operating Expenses (a) :
Research and development personnel-related (excluding equity-based compensation)	$	4,701		$	2,424
External research and development costs – sutacimig		5,795			5,953
External research and development costs – HMB-002		3,506			4,563
External – discovery related costs and other		4,894			981
Personnel-related (excluding equity-based compensation)		1,032			760
External – general and administrative		2,298			1,343
Equity-based compensation expense		1,318			459
Depreciation expense		68			77
Other segment (income) expenses (b)		282			(591	)
Interest income		(1,219	)		(473	)
Income tax expense (benefit)		12			(190	)

Consolidated net loss	$	22,687		$	15,306

(a)	The significant expense categories and amounts align with the segment-level information that is regularly provided to the CODM.

(b)	Other segment expenses include foreign currency exchange loss and other income/expense.

Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses And Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Accrued Liabilities And Other Current Liabilities [Abstract]
Accrued contract research and development costs	$ 3,015	$ 949
Accrued employee compensation	1,286	3,007
Other	2,662	340
Total	$ 6,963	$ 4,296

Equity-Based Compensation - Summary of Assumptions Used For Determining The Fair Value of Warrants Granted (Details)	Mar. 31, 2026 yr
Measurement Input, Expected Dividend Payment [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	0
Measurement Input, Share Price [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	9.37
Minimum [Member] \| Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	89.1
Minimum [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	3.8
Minimum [Member] \| Measurement Input, Expected Term [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	5.8
Maximum [Member] \| Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	91.2
Maximum [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	3.9
Maximum [Member] \| Measurement Input, Expected Term [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of warrants granted	6.2

Convertible Preferred Stock And Convertible Preference Shares (Tables)

3 Months Ended

Mar. 31, 2026

Convertible Preferred Stock And Convertible Preference Shares [Abstract]

Summary of Convertible Preferred Stock And Convertible Preference Shares

As of March 31, 2026 and December 31, 2025, the convertible preferred stock and convertible preference shares consisted of the following (in thousands, except share data):


	March 31, 2026
	Preferred Stock Authorized		Preferred Stock Issued and Outstanding		Carrying Value		Liquidation Preference		Common Stock Issuable Upon Conversion
Series Seed		23,343		23,343	$	5,236	$	3,126		513,546
Series A		225,866		225,866		63,536		53,392		4,969,052
Series B		442,205		442,205		134,975		135,248		9,728,510
Series C		512,991		512,991		156,421		156,898		11,285,802

		1,204,405		1,204,405	$	360,068	$	348,664		26,496,910


	December 31, 2025
	Preference Shares Authorized		Preference Shares Issued and Outstanding		Carrying Value		Liquidation Preference		Ordinary Shares Issuable Upon Conversion
Series Seed		23,343		23,343	$	5,236	$	2,939		513,546
Series A		225,866		225,866		63,536		54,528		4,969,052
Series B		442,205		442,205		134,975		135,248		9,728,510
Series C		512,991		512,991		156,421		156,898		11,285,802

		1,204,405		1,204,405	$	360,068	$	349,613		26,496,910

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Summary of Fair Value Assets And Liabilities Measured On Recurring Basis

The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values as of March 31, 2026

and

December 31, 2025 (in thousands):


	March 31, 2026
	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Marketable securities:
U.S. treasury securities	$	—	$	98,281		—	$	98,281
Non-U.S. debt securities		—		15,390		—		15,390

Total assets measured at fair value	$	—	$	113,671	$	—	$	113,671


	December 31, 2025
	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Cash equivalents:
Certificates of deposit	$	—	$	50,930		—	$	50,930
Non-U.S. debt securities		—		17,638		—		17,638
Marketable securities:
U.S. treasury securities	$	—	$	97,511	$	—	$	97,511

Total assets measured at fair value	$	—	$	166,079	$	—	$	166,079

Property and Equipment, net - Summary of Property And Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Property, Plant and Equipment [Line Items]
Laboratory equipment	$ 887	$ 775
Furniture and fixtures	413	413
Leasehold improvements	82	82
Total property and equipment, at cost	1,444	1,332
Less: accumulated depreciation	(796)	(723)
Property and equipment, net	648	609
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Computer equipment	$ 62	$ 62

Net Loss Per Share - Summary of Outstanding Common Stock and Ordinary Share Equivalents (Details) - shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Convertible preference shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	15,211,108
Convertible preferred stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	26,496,910	0
Warrants to purchase ordinary shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	2,001,010
Warrants to purchase common stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,372,742	0

Convertible Preferred Stock And Convertible Preference Shares

3 Months Ended

Mar. 31, 2026

Convertible Preferred Stock And Convertible Preference Shares [Abstract]

Convertible Preferred Stock and Convertible Preference Shares

9. Convertible Preferred Stock and Convertible Preference Shares

Series Seed Convertible Preference Shares

In November 2020, the Company executed an investment agreement under which it issued and sold 23,343 shares of Series Seed convertible preference shares (“Series Seed Convertible Preference Shares”) for gross cash proceeds of

€

2.5 million ($3.0 million).

Series A Convertible Preference Shares

In July 2021, the Company executed an investment agreement (“Series A Investment Agreement”) to issue and sell up to 225,866 shares of Series A convertible preference shares (“Series A Convertible Preference Shares”) for gross proceeds of up to DKK 346.4 million ($50.9 million). In the initial closing in July 2021, the Company issued 61,600 shares of Series A Convertible Preference Shares. This included DKK 57.2 million ($9.0 million) in gross cash proceeds (37,297 shares) and DKK 37.3 million ($5.9 million) from the conversion of the principal and interest balance of debt (24,303 shares). Pursuant to the Series A Investment Agreement, the Company was obligated to issue and the investors were obligated to purchase an additional 164,266 shares of Series A Convertible Preference Shares for total cash proceeds of DKK 251.9 million ($36.0 million) in three separate closings upon the satisfaction of certain conditions related to clinical development. All of the conditions were achieved prior to February 2023. The Company incurred DKK 1.8 million ($0.3 million) of issuance costs.

Series B Convertible Preference Shares

In February 2023, the Company executed an investment agreement under which it issued and sold 442,205 shares of Series B convertible preference shares (“Series B Convertible Preference Shares”) for gross cash proceeds of $135.2 million. The Company incurred $0.3 million of issuance costs.

Series C Convertible Preference Shares

In October 2025, the Company executed an investment agreement under which it issued and sold 512,991 shares of Series C convertible preference shares (“Series C Convertible Preference Shares”) for gross cash proceeds of $156.9 million. The Company incurred $0.5 million of issuance costs.

In connection with the corporate reorganization, the shareholders of Hemab ApS exchanged their convertible preference shares of Hemab ApS for the same number, class and series of newly issued shares of convertible preferred stock, on a

one-for-one

basis, in Hemab Therapeutic Holdings, Inc.

As of March 31, 2026 and December 31, 2025, the convertible preferred stock and convertible preference shares consisted of the following (in thousands, except share data):


	March 31, 2026
	Preferred Stock Authorized		Preferred Stock Issued and Outstanding		Carrying Value		Liquidation Preference		Common Stock Issuable Upon Conversion
Series Seed		23,343		23,343	$	5,236	$	3,126		513,546
Series A		225,866		225,866		63,536		53,392		4,969,052
Series B		442,205		442,205		134,975		135,248		9,728,510
Series C		512,991		512,991		156,421		156,898		11,285,802

		1,204,405		1,204,405	$	360,068	$	348,664		26,496,910


	December 31, 2025
	Preference Shares Authorized		Preference Shares Issued and Outstanding		Carrying Value		Liquidation Preference		Ordinary Shares Issuable Upon Conversion
Series Seed		23,343		23,343	$	5,236	$	2,939		513,546
Series A		225,866		225,866		63,536		54,528		4,969,052
Series B		442,205		442,205		134,975		135,248		9,728,510
Series C		512,991		512,991		156,421		156,898		11,285,802

		1,204,405		1,204,405	$	360,068	$	349,613		26,496,910

The convertible preferred stock had substantially identical rights to the convertible preference shares. The rights, preferences, and privileges of the convertible preferred stock were as follows as of March 31, 2026:

Liquidation Preference

The Deemed Liquidation Events (as defined in the Company’s amended and restated certificate of incorporation, as amended) included: (a) a merger, consolidation, statutory conversion, transfer of the Company, domestication, or continuance in which (i) the Company is a constituent party or (ii) a subsidiary of the Company is a constituent party and the Company issues shares of its capital stock pursuant to such merger, consolidation, statutory conversion, transfer of the Company, domestication, or continuance, (b) (i) the sale, lease, transfer, exclusive license or other disposition, in a single transaction or series of related transactions, by the Company or any subsidiary of the Company of all or substantially all the assets of the Company and its subsidiaries taken as a whole, or (ii) the sale, lease, transfer, exclusive license or other disposition (whether by merger, consolidation, statutory conversion, transfer of the Company, domestication, continuance or otherwise, and whether in a single transaction or a series of related transactions) of one or more subsidiaries of the Company if substantially all of the assets of the Company and its subsidiaries taken as a whole are held by such subsidiary or subsidiaries, except where such sale, lease, transfer, exclusive license or other disposition is to a wholly owned subsidiary of the Company. In the event of any Deemed Liquidation Event, the proceeds, if any, would have been distributed to the stockholders in accordance with the following priority:

(i)

First, the holders of Series C Convertible Preferred Stock would have, for every share of Series C Convertible Preferred Stock, been entitled to be paid out an amount equal to the greater of (a) one times the applicable Original Issue Price

($305.85),

plus any dividends declared but unpaid thereon, or (b) such amount per share as would have been payable had all shares of Series C Convertible Preferred Stock been converted into Common Stock. If the available proceeds were insufficient to make payment in full on the Series C Convertible Preferred Stock, then the available proceeds would have been allocated pro rata amongst the holders in proportion to their holdings of Series C Convertible Preferred Stock.

(ii)

Second, the holders of Series B and/or Series A Convertible Preferred Stock would have, for every share of Series B and/or Series A Convertible Preferred Stock, been entitled to be paid out an amount equal to the greater of (a) one times the applicable Original Issue Price

($305.85 for Series B and $236.39

for Series A Convertible Preferred Stock), plus any dividends declared but unpaid thereon, or (b) such amount per share as would have been payable had all shares of Series B Convertible Preferred Stock and Series A Convertible Preferred Stock been converted into Common Stock. If the available proceeds were insufficient to make payment in full on the Series B and/or Series A Convertible Preferred Stock, then the available proceeds would have been allocated pro rata amongst the holders in proportion to their holdings of Series B and/or Series A Convertible Preferred Stock.

(iii)

Third, the holders of Series Seed Convertible Preferred Stock would have, for every share of Series Seed Convertible Preferred Stock, been entitled to be paid out an amount equal to the greater of (a) one times the applicable Original Issue Price

($133.92),

plus any dividends declared but unpaid thereon, or (b) such amount per share as would have been payable had all shares of Series Seed Convertible Preferred Stock been converted into Common Stock. If the available proceeds were insufficient to make payment in full on the Series Seed Convertible Preferred Stock, then the available proceeds would have been allocated pro rata amongst the holders in proportion to their holdings of Series Seed Convertible Preferred Stock (together with clauses (i) and (ii) above, the “Liquidation Amount”).

The remaining proceeds, if any, following distribution of the Liquidation Amount would have been distributed to the holder of common stock on a pro rata basis.

Conversion

Shares of convertible preferred stock were convertible into common stock at the option of the holder at any time by dividing the applicable Original Issue Price by the applicable Conversion Price (each as defined in the Company’s amended and restated certificate of incorporation, as amended) in effect at the time of conversion. In connection with the corporate reorganization, the Conversion Prices were set for each series of preferred stock based on the Original Issuance Price, so the convertible preferred stock would be convertible into common stock on a

one-for-one

basis. In addition, the convertible preferred stock was automatically convertible into common stock on a

one-for-one

basis (i) in the event

that

of all convertible preferred stock voting as one share class, including

of the Series C Convertible Preferred Stock (the “Investor Majority”), consented to such conversion, or (ii) in the event of a public offering which generated gross proceeds of not less than

100.0

million.

On May 4, 2026, the Company completed

the

IPO of 19,262,500 shares of its common stock

for

gross proceeds of approximately $346.7

million before deducting underwriting discounts and commissions and estimated offering expenses payable by the Company. In connection with the completion of the IPO, all of the Company’s convertible preferred stock converted into

26,496,910

shares of common stock, and no

shares of preferred stock were outstanding. See Note 14 titled “

Subsequent Events

” for additional information.

Voting

The holders of convertible preferred stock were entitled to the number of votes equal to the number of shares of common stock into which their shares of convertible preferred stock were then convertible, on all matters to be voted upon at all general meetings and written actions in lieu of meetings.

Redemption

Shares of convertible preferred stock were not subject to mandatory redemption. Upon certain events that were outside of the Company’s control, the shares of convertible preferred stock were contingently redeemable at a price equal to the greater of the Liquidation Amount or the amount that would be received on an

as-converted

to common stock basis.

Convertible Preferred Stock And Convertible Preference Shares - Additional Information (Details) $ / shares in Units, € in Millions, kr in Millions, $ in Millions			1 Months Ended					3 Months Ended
	May 04, 2026 USD ($) shares	Oct. 31, 2025 USD ($) shares	Feb. 28, 2023 USD ($) shares	Jul. 31, 2021 USD ($) shares	Jul. 31, 2021 DKK (kr) shares	Nov. 30, 2020 USD ($) shares	Nov. 30, 2020 EUR (€) shares	Mar. 31, 2026 USD ($) $ / shares shares	Dec. 31, 2025 shares
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred stock issued and outstanding								1,204,405	1,204,405
Common Stock Issuable Upon Conversion								26,496,910	26,496,910
Preferred stock, convertible, conversion ratio								50
Proceeds from issuance initial public offering \| $								$ 100.0
Subsequent Event [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Proceeds from issuance initial public offering \| $	$ 317.2
Stock issued during period, shares, conversion of convertible securities	26,496,910
Subsequent Event [Member] \| Preferred Stock [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Preferred stock, shares outstanding	0
IPO [Member] \| Subsequent Event [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Sale of stock, number of shares issued in transaction	2,512,500
Proceeds from issuance initial public offering \| $	$ 346.7
Stock issued during period, shares, new issues	19,262,500
Series Seed Convertible Preference Shares [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Sale of stock, number of shares issued in transaction						23,343	23,343
Proceeds from Issuance of Convertible Preferred Stock						$ 3.0	€ 2.5
Preferred stock issued and outstanding								23,343	23,343
Common Stock Issuable Upon Conversion								513,546	513,546
Preferred stock, liquidation preference per share \| $ / shares								$ 133.92
Series A Convertible Preference Shares [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Proceeds from Issuance of Convertible Preferred Stock				$ 9.0	kr 57.2
Preferred stock, convertible, shares issuable				61,600	61,600
Preferred stock issued and outstanding				37,297	37,297			225,866	225,866
Amount of conversion of principal preferred stock \| kr					kr 37.3
Amount of conversion of interest preferred stock \| $				$ 5.9
Common Stock Issuable Upon Conversion				24,303	24,303			4,969,052	4,969,052
Payments of Stock Issuance Costs				$ 0.3	kr 1.8
Preferred stock, liquidation preference per share \| $ / shares								$ 236.39
Series A Convertible Preference Shares [Member] \| Preferred Stock [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Proceeds from Issuance of Convertible Preferred Stock				$ 36.0	kr 251.9
Common Stock Issuable Upon Conversion				164,266	164,266
Series A Convertible Preference Shares [Member] \| Series A Investment Agreement [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Sale of stock, number of shares issued in transaction				225,866	225,866
Proceeds from Issuance of Convertible Preferred Stock				$ 50.9	kr 346.4
Series B Convertible Preference Shares [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Sale of stock, number of shares issued in transaction			442,205
Proceeds from Issuance of Convertible Preferred Stock \| $			$ 135.2
Preferred stock issued and outstanding								442,205	442,205
Common Stock Issuable Upon Conversion								9,728,510	9,728,510
Payments of Stock Issuance Costs \| $			$ 0.3
Preferred stock, liquidation preference per share \| $ / shares								$ 305.85
Series C Convertible Preference Shares [Member]
Convertible Preferred Stock And Convertible Preference Shares [Line Items]
Sale of stock, number of shares issued in transaction		512,991
Proceeds from Issuance of Convertible Preferred Stock \| $		$ 156.9
Preferred stock issued and outstanding								512,991	512,991
Common Stock Issuable Upon Conversion								11,285,802	11,285,802
Payments of Stock Issuance Costs \| $		$ 0.5
Preferred stock, liquidation preference per share \| $ / shares								$ 305.85
Preferred stock, convertible, conversion ratio								60

Subsequent Events - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended
	May 04, 2026	Apr. 30, 2026	Apr. 24, 2026	Mar. 31, 2026	Dec. 31, 2025
Subsequent Event [Line Items]
Proceeds from issuance initial public offering				$ 100.0
Preferred Stock Authorized				1,204,405	1,204,405
Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from issuance initial public offering	$ 317.2
Stock issued during period, shares, conversion of convertible securities	26,496,910
Note stock split			The Company’s board of directors and stockholders approved a 22-for-one forward stock split of the Company’s issued and outstanding common stock and a proportional adjustment to the existing conversion ratios for the outstanding shares of convertible preferred stock, which became effective on April 24, 2026.
Subsequent Event [Member] \| 2026 Equity Incentive Plan [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized		4,180,000
Share based compensation arrangement by share-based payment award, options, grants in period, gross		306,900
Share based compensation arrangement by share based payment award options grants in period weighted average exercise price		$ 18
Subsequent Event [Member] \| 2026 Employee Stock Purchase Plan [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized		418,000
Subsequent Event [Member] \| Amended And Restated Certificate Of Incorporation [Member]
Subsequent Event [Line Items]
Common stock, shares authorized	400,000,000
Common stock, par or stated value per share	$ 0.0001
Preferred Stock Authorized	5,000,000
Preferred stock, par or stated value per share	$ 0.0001
IPO [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Stock issued during period, shares, new issues	19,262,500
Sale of stock, number of shares issued in transaction	2,512,500
Shares issued, price per share	$ 18
Proceeds from issuance initial public offering	$ 346.7

Segment Reporting - Summary of Reconciliation of Operating Profit (Loss) from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other segment (income) expenses	$ (282)	$ 591
Income tax (expense) benefit	12	(190)
Net loss	(22,687)	(15,306)
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Research and development personnel-related (excluding equity-based compensation)	4,701	2,424
External – discovery related costs and other	4,894	981
Personnel-related (excluding equity-based compensation)	1,032	760
External – general and administrative	2,298	1,343
Equity-based compensation expense	1,318	459
Depreciation expense	68	77
Other segment (income) expenses	282	(591)
Interest income	(1,219)	(473)
Income tax (expense) benefit	12	(190)
Net loss	22,687	15,306
Operating Segments [Member] \| Sutacimig [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
External research and development costs	5,795	5,953
Operating Segments [Member] \| HMB-002 [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
External research and development costs	$ 3,506	$ 4,563

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies License and Collaboration Agreements The Company is party to certain agreements that may require future payments upon the achievement of specified development, regulatory, and commercial milestones, as well as royalty payments. These potential obligations are not recorded as liabilities until the underlying milestone event is deemed probable of occurrence and the related amount is reasonably estimable. Agreement with Novo Nordisk In November 2019, the Company entered into a license agreement with Novo Nordisk A/S (“Novo Nordisk”), pursuant to which Novo Nordisk granted the Company an exclusive (even as to Novo Nordisk), worldwide and sublicensable license under specified patent rights, and a non-exclusive, worldwide and sublicensable license under specified know-how, to research, develop, make, have made, use, offer for sale, sell, import, export or otherwise exploit, or transfer possession of or title in, products (“Novo Licensed Products”), containing bispecific IgG antibodies targeting TLT-1 and Factor VII, including sutacimig, for the treatment of bleeding conditions, including hemophilia (the “Novo Nordisk Agreement”). Under the terms of the Novo Nordisk Agreement, the Company has agreed to use commercially reasonable efforts to develop and commercialize a Novo Licensed Product. The Company is obligated to pay to Novo Nordisk a one-time DKK 40 million milestone payment upon achievement by a Novo Licensed Product of a specified regulatory milestone event, and the Company is also obligated to pay Novo Nordisk tiered royalties, in the low single-digit percentages, on aggregate annual net sales of all Novo Licensed Products, on a Novo Licensed Product-by-Novo Licensed Product and country-by-country basis, until the later of the expiration of the last valid claim in the licensed patents under the Novo Nordisk Agreement covering such Novo Licensed Product in such country and ten years following the first commercial sale of such Novo Licensed Product in such country. The Company currently expects that all of the licensed patents under the Novo Nordisk Agreement will expire by 2040, potentially extending to 2045 with patent term extension. To date, the Company has not made any payments to Novo Nordisk under the Novo Nordisk Agreement. The Novo Nordisk Agreement will continue in force until it is terminated. On expiration of each royalty term, the Company’s license becomes royalty-free, perpetual, and irrevocable with respect to the applicable Novo Licensed Product in the applicable country. Either party may terminate the Novo Nordisk Agreement for the other party’s uncured material breach or insolvency. The Company may terminate the Novo Nordisk Agreement for any reason upon 90 days’ written notice to Novo Nordisk. In the event that Novo Nordisk regains control of the exclusive right to exploit the Novo Licensed Product, the Novo Nordisk Agreement will automatically terminate. Agreement with Genmab In April 2020, the Company entered into a license agreement with Genmab A/S (“Genmab”), pursuant to which Genmab granted the Company an exclusive (even as to Genmab and its affiliates), worldwide and sublicensable license under platform technology patent rights and know-how relating to Genmab’s proprietary DuoBody ® platform to research, develop, make, have made, use, manufacture, import, export and commercialize products comprising bispecific IgG antibodies targeting TLT-1 and Factor VII (the “TLT-1/Factor VII Antibody Products”), including sutacimig, for the treatment of bleeding conditions, including hemophilia (the “Genmab Agreement”). Under the terms of the Genmab Agreement, the Company has agreed to use commercially reasonable efforts to develop, manufacture, obtain regulatory approval for and commercialize TLT-1/Factor VII Antibody Products worldwide. Under the Genmab Agreement, the Company is obligated to pay Genmab a percentage of all net profit (i.e., revenue and other proceeds less specified direct costs the Company incurs to conduct research, development, manufacture and commercialization of TLT-1/Factor VII Antibody Products) the Company or its affiliates receive with respect to any TLT-1/Factor VII Antibody Products, including (1) net profit from commercial sales of TLT-1/Factor VII Antibody Products and any revenue from third parties, other than Novo Nordisk, in respect of a sublicense or assignment with respect to TLT-1/Factor VII Antibody Products, including assignment fees, sublicensing fees, upfront and milestone fees, royalties and other consideration, whether in kind or cash, and (2) the net profit allocated to TLT-1/Factor VII Antibody Products that the Company or its affiliates receive if the Company undergoes a change of control (other than an acquisition by Novo Nordisk). The percentage of net profit the Company owes with respect to each TLT-1/Factor VII Antibody Product is in the low teens from the effective date of the Genmab Agreement until the first commercial sale of such TLT-1/Factor VII Antibody Product. From and after the first commercial sale of a TLT-1/Factor VII Antibody Product, the percentage of net profit the Company owes with respect to such TLT-1/Factor VII Antibody Product is in the high single digits in all territories in which the Company commercializes such TLT-1/Factor VII Antibody Product and in the mid-teens in all territories in which a third party, other than Novo Nordisk, commercializes such TLT-1/Factor VII Antibody Product. The Company is obligated to pay such percentage of net profit on a country-by-country and TLT-1/Factor VII Antibody Product-by-TLT-1/Factor VII Antibody Product basis until the later of the expiration of the last-to-expire of the platform technology patent rights licensed under the Genmab Agreement covering such TLT-1/Factor VII Antibody Product in such country and twelve years following the first commercial sale of such TLT-1/Factor VII Antibody Product in such country, which the Company refers to as the net profit share term. Following the expiration of the last-to-expire of the platform technology patent rights licensed under the Genmab Agreement covering a given TLT-1/Factor VII Antibody Product in a given country, the percentage of net profit that the Company is obligated to pay with respect to sales of such TLT-1/Factor VII Antibody Product in such country will be reduced by a specified percentage for the remainder of the net profit share term for such TLT-1/Factor VII Antibody Product in such country. The Company currently expects that all of the platform technology patent rights licensed under the Genmab Agreement will expire by 2032, though this date may be extended if, for example, Genmab files additional patents covering its platform technology. To date, the Company has not made any payments to Genmab under the Genmab Agreement. In the event the Company seeks to sell, license or otherwise dispose of its rights to TLT-1/Factor VII Antibody Products, including through a change of control to any third party other than Novo Nordisk, the Company is obligated to provide Genmab the right to participate in any bidding process as a bona fide potential acquirer of such rights. Unless earlier terminated, the Genmab Agreement will expire, on a TLT-1/Factor VII Antibody Product-by-TLT-1/Factor VII Antibody Product and country-by-country basis, upon the expiration of the last net profit share term for such TLT-1/Factor VII Antibody Product in such country. On expiration of each net profit share term, the Company’s license becomes perpetual, fully paid-up and non-exclusive with respect to the applicable TLT-1/Factor VII Antibody Product in the applicable country. Either party may terminate the Genmab Agreement for the other party’s uncured material breach or insolvency or in certain events of force majeure. Genmab may terminate the Genmab Agreement if the Company or its affiliates or sublicensees challenge any of the platform technology patent rights licensed under the Genmab Agreement. The Company may terminate the Genmab Agreement for any reason upon 120 days written notice to Genmab. If Novo Nordisk obtains from us the exclusive right to exploit TLT-1/Factor VII Antibody Products, including upon termination of the Novo Nordisk Agreement, then the Genmab Agreement will terminate in all territories in which Novo Nordisk obtains such exclusive rights. 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 arising out of the relationship between such parties and the Company. In addition, the Company has entered into indemnification agreements with members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations as of March 31, 2026 and December 31, 2025. Legal Proceedings The Company, from time to time, may be party to litigation arising in the ordinary course of business. The Company was not subject to any material legal proceedings during the three months ended March 31, 2026 and year ended December 31, 2025 and, to the best of its knowledge, no material legal proceedings are currently pending or threatened.

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2026	May 08, 2026
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Entity Central Index Key	0002114044
Document Quarterly Report	true
Document Transition Report	false
Entity Registrant Name	Hemab Therapeutics Holdings, Inc.
Entity File Number	001-43250
Document Period End Date	Mar. 31, 2026
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Tax Identification Number	41-4241952
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	101 Main Street
Entity Address, Address Line Two	Suite 1220
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02142
City Area Code	617
Local Phone Number	553-3952
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	COAG
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		46,705,410

Equity-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2022
Warrant [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Class of warrant or right, outstanding	5,227,222
Share-based compensation, description	The service-based warrant grants generally vest over a four-year service period, with the first 25% vesting on the one-year anniversary of the vesting start date and the remaining vesting in equal monthly installments over the following 36 months
Share-based compensation expiration period	10 years
Weighted- average exercise price per share, granted	$ 6
Warrants fair value	$ 0.8
Unrecognized compensation expense	$ 18.8
Performance Based Warrants [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation service period		4 years
Weighted Average [Member] \| Warrant [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted- average exercise price per share, granted	$ 7.4
Weighted-average period	3 years 4 months 24 days

Equity-Based Compensation

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Equity-Based Compensation

11. Equity-Based Compensation

Warrants

As of March 31, 2026, the Company had

5,227,222

warrant grants outstanding. Each vested warrant entitles the warrant holder the right to subscribe for one share of common stock. Holders of stock warrants are entitled to exercise the vested portion of the warrant.

The service-based warrant grants generally vest over a four-year service period, with the first 25% vesting on the

one-year

anniversary of the vesting start date and the remaining vesting in equal monthly installments over the following 36 months. The service-based and performance-based warrant grants vest in the same manner as the service-based only awards to the extent the performance condition is met. The Company’s warrants expire ten years after the initial grant date if they remain unexercised. Upon the exercise date, the Company issues new

shares of

common stock to the participant.

No warrants were exercised during the three months ended March 31, 2026.

The following assumptions were used in determining the fair value of warrants granted during the three months ended March 31, 2026:


		Three Months Ended March 31, 2026
Expected volatility		89.1% - 91.2%
Risk-free interest rate		3.8% - 3.9%
Expected term (in years)		5.8 - 6.2
Expected dividend yield		0%
Fair value per share		$9.37

The following table summarizes the Company’s warrants for the three months ended March 31, 2026:


	Number of Warrants			Weighted- average exercise price per share		Weighted- average remaining contractual term (in years)		Aggregate intrinsic value (in thousands)
Outstanding, December 31, 2025		2,101,352		$	5.68		7.4	$	2,409
Granted		2,294,798		$	6.00		—	$	—
Forfeited		(23,408	)	$	6.97		—	$	—

Outstanding, March 31, 2026		4,372,742		$	5.84		8.6	$	28,045

Exercisable at March 31, 2026		1,568,666		$	5.12		6.9	$	11,141

Vested and expected to vest, March 31, 2026		4,372,742		$	5.84		8.6	$	28,045

The weighted-average grant date fair value of the shares underlying warrants granted during the three months ended March 31, 2026 was

7.40

per share. The total fair value of the shares underlying warrants that vested during the three months ended March 31, 2026 was

0.8

million.

Performance-Based Warrants

During 2022, the Company issued warrants to certain employees that included two components: (i) a performance condition that is achieved upon the separate closings of the Series A Convertible Preferred Shares, and (ii) a service condition where the employee provides service over a four-year period. Upon the final closing of the Series A Convertible Preferred Shares in January 2023, all performance conditions had been satisfied and the warrants were subject to ongoing service conditions. Equity-based compensation expense is recognized using an accelerated attribution method over the remaining requisite service period.

Equity-Based Compensation

Equity-based compensation expense recorded as research and development and general and administrative expenses is as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Research and development	$	565	$	180
General and administrative		753		279

Total	$	1,318	$	459

As of March 31, 2026, the total unrecognized compensation expense related to the Company’s warrants was $18.8 million, which the Company expects to recognize over a weighted-average period of approximately 3.4 years.

Segment Reporting - Summary of Long-Lived Assets By Geographic Location (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 1,587	$ 2,368
United States of America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	348	786
Denmark [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 1,239	$ 1,582

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2026
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The Company’s condensed consolidated financial statements include the accounts of its subsidiaries, Hemab ApS and Hemab Therapeutics, Inc., which was a wholly owned subsidiary of Hemab ApS until April 1, 2026. As a result of the corporate reorganization described in Note 1 “Description of Business and Liquidity—Corporate Reorganization”, Hemab ApS became a wholly owned subsidiary of Hemab Therapeutics Holdings, Inc. and, accordingly, the Company’s consolidated financial statements are those of Hemab Therapeutics Holdings, Inc. for the periods after the corporate reorganization and are those of Hemab ApS for historical periods before the corporate reorganization. Management has concluded the Company has a single reporting segment for purposes of reporting financial condition and results of operations. All intercompany transactions and balances have been eliminated in accordance with ASC 810, Consolidation .
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Unaudited Interim Consolidated Financial Information	Unaudited Interim Consolidated Financial Information The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements of Hemab ApS and reflect, in the opinion of management, all adjustments of a normal and recurring nature that are necessary for the fair statement of the Company’s financial position as of March 31, 2026 and its results of operations and cash flows for the three months ended March 31, 2026 and 2025. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, or for any other future annual or interim period. The condensed consolidated balance sheet as of December 31, 2025 included herein was derived from the audited financial statements of Hemab ApS as of that date. Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with GAAP have been condensed or omitted from these unaudited condensed consolidated financial statements.
Foreign Currency	Foreign Currency The financial statements are presented in U.S. dollars, the Company’s reporting currency. The functional currency of Hemab ApS and Hemab Therapeutics, Inc. is the U.S. dollar. Transaction gains and losses resulting from exchange rate changes on transactions denominated in currencies other than the U.S. dollar are recognized in other (expense) income, net in the consolidated statements of operations and comprehensive loss.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and in these accompanying notes. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors and assumptions that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates, which include, but are not limited to, accrued research and development expenses, the fair value of the ordinary shares and warrants for equity-based compensation expense, and the valuation of the Company’s deferred tax assets. Changes in estimates are recorded in the period in which they become known.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk primarily consist of cash, cash equivalents, and marketable securities. The Company’s investment portfolio is primarily comprised of short term debt securities issued by the U.S., Danish, and German governments. The Company places its cash in financial institutions that management believes to be of high credit quality and, consequently, the Company does not believe it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Bank accounts in the United States are insured by the Federal Deposit Insurance Corporation up to $250,000.
Deferred Offering Costs	Deferred Offering Costs Deferred offering costs consist of certain legal, professional, accounting and other third-party fees that are directly associated with the IPO. These direct costs are capitalized and recorded as other non-current assets on the condensed consolidated balance sheets. The deferred offering costs will be recorded against the IPO proceeds upon the consummation of the IPO, which was completed on May 4, 2026. As of March 31, 2026, the Company had $2.7 million of deferred offering costs.
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes net loss as well as other changes in stockholders’ deficit that result from transactions and events other than those with stockholders. The Company’s unrealized gains and losses on available-for sale-debt securities represent the only component of other comprehensive income (loss).
Recently Issued Accounting Standards	Recently Issued Accounting Standards In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). 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 the Company in the annual periods beginning after December 15, 2025. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. The Company is currently assessing the impact adoption of ASU 2023-09 will have on its consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”). ASU 2024-03 will require disclosure of disaggregated information about certain income statement expense line items on an annual and interim basis, including purchases of inventory, employee compensation, depreciation, intangible asset amortization and depletion for each income statement line item that contains those expenses. ASU 2024-03 also will require certain amounts already disclosed under existing U.S. GAAP to also be disclosed as a separate category in disaggregated expense table(s), if those amounts are recognized in the relevant expense line item. The amendments in ASU 2024-03 will be effective for the Company in annual reporting periods beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027. The Company is currently assessing the impact adoption of ASU 2024-03 will have on its consolidated financial statements and related disclosures. In December 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements (“ASU 2025-11”) to provide clarifications intended to improve the consistency and usability of interim disclosure requirements. ASU 2025-11 includes a comprehensive listing of required interim disclosures and a new disclosure principle for reporting material events occurring after the most recent annual period. ASU 2025-11 is effective for interim periods within annual reporting periods beginning after December 15, 2027, and early adoption is permitted. The amendments in this update permit an entity to apply the new guidance using a prospective or retrospective approach. The Company is currently assessing the impact adoption of ASU 2025-11 will have on its consolidated financial statements and related disclosures.

Commitments and Contingencies - Additional Information (Details) kr in Millions	Mar. 31, 2026 DKK (kr)
Commitments and Contingencies Disclosure [Abstract]
Payment for licensed product	kr 40

Common Stock and Ordinary Shares - Additional Information (Details) - shares		3 Months Ended
	May 04, 2026	Mar. 31, 2026	Dec. 31, 2025
Class of Stock [Line Items]
Common stock, voting rights		The holders of common stock and ordinary shares are entitled to one vote per share on all matters to be voted upon at all general meetings and written actions in lieu of meetings.
Subsequent Event [Member] \| IPO [Member]
Class of Stock [Line Items]
Stock issued during period, shares, new issues	19,262,500
Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares authorized		1,446,166	0
Common stock, shares, issued		946,000	0
Common stock, shares, outstanding		946,000	0

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
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-Paragraph 8A
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
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Reference 6: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-Subparagraph (b)
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (c)
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Net Loss Per Share

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Net Loss Per Share

12. Net Loss Per Share

The following table sets forth the outstanding shares of common stock and ordinary share equivalents, presented based on amounts outstanding at each period end, that were excluded from the calculation of diluted net loss per share for the periods indicated because including them would have been anti-dilutive:


	Three Months Ended March 31,
	2026		2025
Convertible preference shares		—		15,211,108
Convertible preferred stock		26,496,910		—
Warrants to purchase ordinary shares		—		2,001,010
Warrants to purchase common stock		4,372,742		—

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Summary of Outstanding Common Stock and Ordinary Share Equivalents


	Three Months Ended March 31,
	2026		2025
Convertible preference shares		—		15,211,108
Convertible preferred stock		26,496,910		—
Warrants to purchase ordinary shares		—		2,001,010
Warrants to purchase common stock		4,372,742		—

Available-For-Sale Debt Securities

3 Months Ended

Mar. 31, 2026

Investments, Debt and Equity Securities [Abstract]

Available-For-Sale Debt Securities

Available-For-Sale

Debt Securities

Available-for-sale debt

securities consisted of the following as of March 31, 2026 and December 31, 2025 (in thousands):


	March 31, 2026
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Marketable securities:
U.S. treasury securities	$	98,393	$	—	$	(112	)	$	98,281
Non-U.S. debt securities		15,717		—		(327	)		15,390

Total	$	114,110	$	—	$	(439	)	$	113,671


	December 31, 2025
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Non-U.S. debt securities	$	17,415	$	223	$	—		$	17,638
Marketable securities:
U.S. treasury securities		97,559		—		(48	)		97,511

Total	$	114,974	$	223	$	(48	)	$	115,149

All of the Company’s

available-for-sale

debt securities as of March 31, 2026 and December 31, 2025 had a contractual maturity of less than 12 months. The Company did not realize any gains or losses recognized on the sale of

available-for-sale

debt securities during the three months ended March 31, 2026 and year ended December 31, 2025, and, as a result, the Company did not reclassify any amounts out of accumulated comprehensive loss. All of the Company’s

available-for-sale

debt securities as of March 31, 2026 and December 31, 2025 are classified as current as they mature within one year from the balance sheet date.

As of March 31, 2026, the Company held four securities in an unrealized loss position with an aggregate fair value of $113.7 million. As of December 31, 2025, the Company held three securities in an unrealized loss position with an aggregate fair value of $97.5 million. None of the securities were in an unrealized loss position for greater than 12 months.

The Company has the intent and ability to hold its debt securities until recovery of their amortized cost bases, which may be maturity. As a result, the Company did not recognize any differences between the fair value and amortized cost basis as a loss in its consolidated statements of operations and comprehensive loss for the three months ended March 31, 2026 and year ended December 31, 2025. The Company did not record any credit-related impairments for its

available-for-sale

debt securities for the three months ended March 31, 2026 and year ended December 31, 2025.

Segment Reporting - Additional Information (Details)	3 Months Ended
Segment Reporting - Additional Information (Details)	Mar. 31, 2026 Segment
Segment Reporting Information [Line Items]
Number of reportable segments	1
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	Chief Executive Officer [Member]

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 49,860	$ 87,974
Marketable securities	113,671	97,511
Prepaid expenses and other current assets	5,900	7,066
Total current assets	169,431	192,551
Property and equipment, net	648	609
Operating right-of-use assets	939	1,092
Other non-current assets	4,240	531
Total assets	175,258	194,783
Current liabilities:
Accounts payable	5,682	5,734
Accrued expenses and other current liabilities	6,963	4,296
Operating lease liabilities	544	647
Total current liabilities	13,189	10,677
Operating lease liabilities, net of current portion	519	573
Total liabilities	13,708	11,250
Commitments and contingencies (Note 8)
Stockholders' deficit:
Additional Paid in Capital	6,366	4,916
Accumulated other comprehensive (loss) income	(439)	175
Accumulated deficit	(204,545)	(181,858)
Total stockholders' deficit	(198,618)	(176,635)
Total liabilities, convertible preference shares, convertible preferred stock and stockholders' deficit	175,258	194,783
Series Seed Convertible Preference Shares And Convertible Preferred Stock [Member]
Convertible preferred stock and convertible preference shares:
Preferred Stock Value	5,236	5,236
Series A Convertible Preference Shares And Convertible Preferred Stock [Member]
Convertible preferred stock and convertible preference shares:
Preferred Stock Value	63,536	63,536
Series B Convertible Preference Shares And Convertible Preferred Stock [Member]
Convertible preferred stock and convertible preference shares:
Preferred Stock Value	134,975	134,975
Series C Convertible Preference Shares And Convertible Preferred Stock [Member]
Convertible preferred stock and convertible preference shares:
Preferred Stock Value	156,421	156,421
Ordinary Shares [Member]
Stockholders' deficit:
Stockholders' deficit:	0	132
Common Stock [Member]
Stockholders' deficit:
Stockholders' deficit:	$ 0	$ 0

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Operating expenses:
Research and development	$ 19,461	$ 14,101
General and administrative	4,151	2,459
Total operating expenses	23,612	16,560
Loss from operations	(23,612)	(16,560)
Other income (expense), net:
Interest income	1,219	473
Other (expense) income, net	(282)	591
Total other income, net	937	1,064
Loss before income tax expense	(22,675)	(15,496)
Income tax (expense) benefit	(12)	190
Net loss	$ (22,687)	$ (15,306)
Earnings Per Share, Basic	$ (23.98)	$ (16.18)
Earnings Per Share, Diluted	$ (23.98)	$ (16.18)
Weighted Average Number of Shares Outstanding, Basic	946,000	946,000
Weighted Average Number of Shares Outstanding, Diluted	946,000	946,000
Other comprehensive (loss) income:
Net Income (Loss)	$ (22,687)	$ (15,306)
Net unrealized gain (loss) on available-for-sale debt securities	(614)	974
Total comprehensive loss	$ (23,301)	$ (14,332)

Accrued Expenses and Other Current Liabilities

3 Months Ended

Mar. 31, 2026

Accrued Liabilities And Other Current Liabilities [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):


	As of March 31, 2026		As of December 31, 2025
Accrued contract research and development costs	$	3,015	$	949
Accrued employee compensation		1,286		3,007
Other		2,662		340

Total	$	6,963	$	4,296

Prepaid Expenses and Other Current Assets

3 Months Ended

Mar. 31, 2026

Prepaid Expense and Other Assets, Current [Abstract]

Prepaid Expenses and Other Current Assets

5. Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the

following

(in thousands):


	As of March 31, 2026		As of December 31, 2025
Prepaid expenses	$	4,470	$	4,437
Other receivables		1,430		2,629

Total	$	5,900	$	7,066

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2026
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Events The Company evaluated subsequent events through the date on which these financial statements were issued to ensure that these condensed consolidated financial statements include appropriate disclosure of events both recognized in the financial statements as of March 31, 2026 and events which occurred subsequently but not recognized in the financial statements. Corporate Reorganization On April 1, 2026, following the corporate reorganization, on March 31, 2026, Hemab ApS transferred its shares of Hemab Therapeutics Inc., a Delaware corporation and wholly-owned subsidiary of Hemab ApS, to Hemab Therapeutics Holdings, Inc. in exchange for the issuance of a promissory note and, as a result, Hemab Therapeutics Inc. became a wholly owned subsidiary of Hemab Therapeutics Holdings, Inc. See Note 1 titled “Description of Business and Liquidity—Corporate Reorganization” for additional information on the corporate reorganization. Initial Public Offering On May 4, 2026, the Company completed the IPO of 19,262,500 shares of its common stock, which included the exercise in full by the underwriters of their option to purchase 2,512,500 additional shares of common stock, at a public offering price of $18.00 per share. The net proceeds to the Company from the IPO were approximately $317.2 million after deducting underwriting discounts and commissions and offering expenses payable by the Company. In connection with the completion of the IPO, all shares of the Company’s preferred stock were converted into 26,496,910 shares of common stock, and no shares of preferred stock were thereafter outstanding. In connection with the closing of the IPO, on May 4, 2026, the Company’s filed a restated certificate of incorporation with the Secretary of State of the State of Delaware, which authorizes 400,000,000 shares of common stock, par value $0.0001 per share, and 5,000,000 shares of undesignated preferred stock, par value $0.0001 per share. Stock Split The Company’s board of directors and stockholders approved a 22-for-one forward stock split of the Company’s issued and outstanding common stock and a proportional adjustment to the existing conversion ratios for the outstanding shares of convertible preferred stock, which became effective on April 24, 2026. Accordingly, all share and per share amounts for all periods presented in the accompanying condensed consolidated financial statements and the notes thereto have been retroactively adjusted, where applicable, to reflect the stock split. 2026 Equity Plans In April 2026, the Company’s board of directors adopted and the Company’s stockholders approved the 2026 Equity Incentive Plan (the “2026 Plan”), which became effective immediately prior to the effectiveness of the registration statement for the IPO. The 2026 Plan initially provides for the grant of awards with respect to 4,180,000 shares of common stock, of which the Company granted stock options to purchase an aggregate of 306,900 shares of common stock, at an exercise price per share equal to the initial public offering price of $18.00, in connection with the IPO. In April 2026 the Company’s board of directors adopted and the Company’s stockholders approved the 2026 Employee Stock Purchase Plan (the “2026 ESPP”), which became effective immediately prior to the effectiveness of the registration statement for the IPO. The 2026 ESPP initially provides participating employees with the opportunity to purchase up to an aggregate of 418,000 shares of common stock.

Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses And Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid expenses	$ 4,470	$ 4,437
Other receivables	1,430	2,629
Total	$ 5,900	$ 7,066

Summary of Significant Accounting Policies - Additional Information (Details)	Mar. 31, 2026 USD ($)
Accounting Policies [Abstract]
Insured Bank Deposits, Maximum	$ 250,000
Deferred Offering Costs	$ 2,700,000

Fair Value Measurements

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

and

December 31, 2025 (in thousands):


	March 31, 2026
	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Marketable securities:
U.S. treasury securities	$	—	$	98,281		—	$	98,281
Non-U.S. debt securities		—		15,390		—		15,390

Total assets measured at fair value	$	—	$	113,671	$	—	$	113,671


	December 31, 2025
	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Cash equivalents:
Certificates of deposit	$	—	$	50,930		—	$	50,930
Non-U.S. debt securities		—		17,638		—		17,638
Marketable securities:
U.S. treasury securities	$	—	$	97,511	$	—	$	97,511

Total assets measured at fair value	$	—	$	166,079	$	—	$	166,079

The Company’s cash equivalents and marketable securities were valued based on Level 2 inputs and in determining the fair value the Company relied on quoted prices for similar securities in active markets or other inputs that are observable or can be corroborated by observable market data.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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-Paragraph 107
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025
Pay vs Performance Disclosure
Net Income (Loss)	$ (22,687)	$ (15,306)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Cash flows from operating activities:
Net loss	$ (22,687)	$ (15,306)
Adjustments to reconcile net loss to net cash used in operating activities:
Equity-based compensation	1,318	459
Depreciation and amortization	73	75
Non-cash lease expense	153	140
Accretion of discount on available-for-sale debt securities	(816)	(208)
Other non-cash items		381
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	1,166	(65)
Other non-current assets	(1,016)	(800)
Accounts payable	(52)	2,881
Accrued expenses and other current liabilities	434	(434)
Operating lease liabilities	(157)	(139)
Other non-current liabilities		(17)
Net cash used in operating activities	(21,584)	(13,033)
Cash flows from investing activities:
Purchases of available-for-sale debt securities	(15,735)	(19,948)
Maturities of available-for-sale debt securities		13,970
Purchases of property and equipment	(112)	(16)
Net cash used in investing activities	(15,847)	(5,994)
Cash flows from financing activities:
Payment of offering costs	(414)
Principal payments on finance lease	(46)	(29)
Net cash used in financing activities	(460)	(29)
Effect of foreign exchange rate changes on cash and cash equivalents	(223)
Net decrease in cash and cash equivalents	(38,114)	(19,056)
Cash and cash equivalents at beginning of period	87,974	74,407
Cash and cash equivalents at end of period	49,860	55,351
Supplemental disclosure of cash flow activities:
Cash paid for interest		$ 3
Supplemental disclosure of non-cash investing and financing activities:
Deferred offering costs included in accrued expenses and accounts payable	$ 2,279

Condensed Consolidated Balance Sheets (Parenthetical) $ in Thousands	Mar. 31, 2026 USD ($) $ / shares shares	Mar. 31, 2026 kr / shares	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2025 kr / shares
Preferred stock, shares authorized.	1,204,405		1,204,405
Preferred stock, shares issued	1,204,405		1,204,405
Preferred stock, liquidation preference, value \| $	$ 348,664		$ 349,613
Series Seed Convertible Preference Shares And Convertible Preferred Stock [Member]
Preferred stock, par or stated value per share \| (per share)	$ 0.0001	kr 1	$ 0.0001	kr 1
Preferred stock, shares authorized.	23,343		23,343
Preferred stock, shares issued	23,343		23,343
Preferred stock, shares outstanding	23,343		23,343
Preferred stock, liquidation preference, value \| $	$ 3,126		$ 2,939
Series A Convertible Preference Shares And Convertible Preferred Stock [Member]
Preferred stock, par or stated value per share \| (per share)	$ 0.0001	1	$ 0.0001	1
Preferred stock, shares authorized.	225,866		225,866
Preferred stock, shares issued	225,866		225,866
Preferred stock, shares outstanding	225,866		225,866
Preferred stock, liquidation preference, value \| $	$ 53,392		$ 54,528
Series B Convertible Preference Shares And Convertible Preferred Stock [Member]
Preferred stock, par or stated value per share \| (per share)	$ 0.0001	1	$ 0.0001	1
Preferred stock, shares authorized.	442,205		442,205
Preferred stock, shares issued	442,205		442,205
Preferred stock, shares outstanding	442,205		442,205
Preferred stock, liquidation preference, value \| $	$ 135,248		$ 135,248
Series C Convertible Preference Shares And Convertible Preferred Stock [Member]
Preferred stock, par or stated value per share \| (per share)	$ 0.0001	1	$ 0.0001	1
Preferred stock, shares authorized.	512,991		512,991
Preferred stock, shares issued	512,991		512,991
Preferred stock, shares outstanding	512,991		512,991
Preferred stock, liquidation preference, value \| $	$ 156,898		$ 156,898
Common Stock [Member]
Common stock, par or stated value per share \| $ / shares	$ 0.0001		$ 0.0001
Common stock, shares authorized	1,446,166		0
Common stock, shares, issued	946,000		0
Common stock, shares, outstanding	946,000		0
Ordinary Shares [Member]
Common stock, par or stated value per share \| kr / shares		kr 1		kr 1
Common stock, shares authorized	0		946,000
Common stock, shares, issued	0		946,000
Common stock, shares, outstanding	0		946,000

Accrued Expenses and Other Current Liabilities (Tables)

3 Months Ended

Mar. 31, 2026

Accrued Liabilities And Other Current Liabilities [Abstract]

Summary of Accrued Expenses And Other Current Liabilities

Accrued expenses and other current liabilities consist of the following (in thousands):


	As of March 31, 2026		As of December 31, 2025
Accrued contract research and development costs	$	3,015	$	949
Accrued employee compensation		1,286		3,007
Other		2,662		340

Total	$	6,963	$	4,296

Prepaid Expenses and Other Current Assets (Tables)

3 Months Ended

Mar. 31, 2026

Prepaid Expense and Other Assets, Current [Abstract]

Summary of Prepaid Expenses And Other Current Assets

Prepaid expenses and other current assets consisted of the

following

(in thousands):


	As of March 31, 2026		As of December 31, 2025
Prepaid expenses	$	4,470	$	4,437
Other receivables		1,430		2,629

Total	$	5,900	$	7,066

Common Stock and Ordinary Shares	3 Months Ended
Common Stock and Ordinary Shares	Mar. 31, 2026
Stockholders' Equity Note [Abstract]
Common Stock and Ordinary Shares	10. Common Stock and Ordinary Shares As of March 31, 2026, the Company had 1,446,166 shares of common stock authorized for issuance, and 946,000 shares of common stock issued and outstanding. The holders of shares of common stock and ordinary shares were entitled to an allocation and distribution of proceeds in a Liquidation Event subject to the Liquidation Amount due to the holders of convertible preferred stock. When the Liquidation Amount had been paid in full, any remaining proceeds would have been distributed to the holders of common stock or ordinary shares, as applicable, on a pro rata basis. The holders of common stock and ordinary shares are entitled to one vote per share on all matters to be voted upon at all general meetings and written actions in lieu of meetings. On May 4, 2026, the Company completed t h e IPO of 19,262,500 shares of its common stock. See Note 14 titled “ Subsequent Events ” for additional information.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Property and Equipment, net (Tables)

3 Months Ended

Mar. 31, 2026

Property, Plant and Equipment [Abstract]

Summary of Property And Equipment, Net

Property and equipment, net, consisted of the following (in thousands):


	As of March 31, 2026			As of December 31, 2025
Laboratory equipment	$	887		$	775
Furniture and fixtures		413			413
Leasehold improvements		82			82
Computer equipment		62			62

Total property and equipment, at cost		1,444			1,332
Less: accumulated depreciation		(796	)		(723	)

Property and equipment, net	$	648		$	609

Condensed Consolidated Statements of Changes in Convertible Preference Shares, Convertible Preferred Stock and Stockholders' Deficit - USD ($) $ in Thousands	Total	Series Seed Convertible Preference Shares [Member]	Series A Convertible Preference Shares [Member]	Series B Convertible Preference Shares [Member]	Series C Convertible Preference Shares [Member]	Series Seed Convertible Preferred Stock [Member]	Series A Convertible Preferred Stock [Member]	Series B Convertible Preferred Stock [Member]	Series C Convertible Preferred Stock [Member]	Ordinary Shares [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]
Beginning balance ,shares at Dec. 31, 2024		23,343	225,866	442,205						946,000
Beginning balance, Amount at Dec. 31, 2024	$ (115,273)	$ 5,236	$ 63,536	$ 134,975						$ 132		$ 2,905	$ (365)	$ (117,945)
Equity-based compensation	459											459
Other comprehensive income	974												974
Net Income (Loss)	(15,306)													(15,306)
Ending balance, shares at Mar. 31, 2025		23,343	225,866	442,205						946,000
Ending balance, Amount at Mar. 31, 2025	(129,146)	$ 5,236	$ 63,536	$ 134,975						$ 132		3,364	609	(133,251)
Beginning balance ,shares at Dec. 31, 2025		23,343	225,866	442,205	512,991					946,000
Beginning balance, Amount at Dec. 31, 2025	(176,635)	$ 5,236	$ 63,536	$ 134,975	$ 156,421					$ 132		4,916	175	(181,858)
Effect of Reorganization, Shares		(23,343)	(225,866)	(442,205)	(512,991)	23,343	225,866	442,205	512,991	(946,000)	946,000
Effect of Reorganization		$ (5,236)	$ (63,536)	$ (134,975)	$ (156,421)	$ 5,236	$ 63,536	$ 134,975	$ 156,421	$ (132)		132
Equity-based compensation	1,318											1,318
Other comprehensive income	(614)												(614)
Net Income (Loss)	(22,687)													(22,687)
Ending balance, shares at Mar. 31, 2026						23,343	225,866	442,205	512,991		946,000
Ending balance, Amount at Mar. 31, 2026	$ (198,618)					$ 5,236	$ 63,536	$ 134,975	$ 156,421			$ 6,366	$ (439)	$ (204,545)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

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+ Details

- Definition

Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity.

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+ Details

Description of Business and Liquidity - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents, and marketable securities	$ 163,500
Net proceeds from the IPO	317,200
Retained Earnings (Accumulated Deficit)	$ (204,545)	$ (181,858)

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Segment Reporting

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Segment Reporting

13. Segment Reporting

The Company has one operating segment. The Company’s operating segment is engaged in the research and development of prophylactic therapeutics for bleeding disorders. The Company’s

Chief Executive Officer

and Chief Financial Officer/General Manager are together considered the Company’s CODM and together manage the Company’s operations on a consolidated basis for the purposes of assessing performance and allocating resources based on net loss that also is reported on the consolidated statement of operations as consolidated net loss. This financial metric is used by the CODM to make key operating decisions such as the allocation of capital between program expenses, early-stage discovery expenses, and general and administrative expense, including headcount and facilities decisions. The measure of segment assets is reported on the balance sheet as total consolidated assets. The following table presents long-lived assets by geographic location as of March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
	2026		2025
United States of America	$	348	$	786
Denmark		1,239		1,582

	$	1,587	$	2,368

The following table presents selected financial information about the Company’s single operating segment for the three months ended March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
	2026			2025
Operating Expenses (a) :
Research and development personnel-related (excluding equity-based compensation)	$	4,701		$	2,424
External research and development costs – sutacimig		5,795			5,953
External research and development costs – HMB-002		3,506			4,563
External – discovery related costs and other		4,894			981
Personnel-related (excluding equity-based compensation)		1,032			760
External – general and administrative		2,298			1,343
Equity-based compensation expense		1,318			459
Depreciation expense		68			77
Other segment (income) expenses (b)		282			(591	)
Interest income		(1,219	)		(473	)
Income tax expense (benefit)		12			(190	)

Consolidated net loss	$	22,687		$	15,306

(a)	The significant expense categories and amounts align with the segment-level information that is regularly provided to the CODM.

(b)	Other segment expenses include foreign currency exchange loss and other income/expense.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details