Description of Business and Liquidity	3 Months Ended
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.

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.

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.

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.

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.

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.