Organization	12 Months Ended
Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Note 1. Organization Organization Biomea Fusion, Inc., (the Company), was established in the state of Delaware in August 2017 as Biomea Fusion, LLC. In December 2020, all outstanding membership interests in Biomea Fusion, LLC were converted into equity interests in the Company. The capitalization information included in these financial statements is consistently presented as if it is that of Biomea Fusion, Inc., even during the prior period when investors held their equity interests in Biomea Fusion, LLC. The Company is a clinical-stage biopharmaceutical company dedicated to discovering and developing novel covalent small molecules to treat and improve the lives of patients with genetically defined cancers and metabolic diseases. Since its inception in 2017, the Company has built its proprietary FUSIONTM System platform to design and develop a pipeline of novel covalent product candidates. Forward Stock Split In April 2021, the Company’s board of directors approved an amended and restated certificate of incorporation to effect a split of shares of the Company’s outstanding capital at a ratio of 8.84-for-1 (the Forward Stock Split) effective as of April 12, 2021. The number of authorized shares and the par values of the common stock and convertible preferred stock were not adjusted as a result of the Forward Stock Split. All references to common stock, options to purchase common stock, convertible preferred stock, share data, per share data and related information contained in the financial statements have been retrospectively adjusted to reflect the effect of the Forward Stock Split for all periods presented. Initial Public Offering On April 16, 2021, the Company’s registration statement on Form S-1 (File No. 333-254793) relating to its initial public offering (IPO) of common stock became effective. The IPO closed on April 20, 2021 at which time the Company issued an aggregate of 9,000,000 shares of its common stock at a price of $17.00 per share. Subsequent to the close, an additional 823,532 shares were issued in connection with the partial exercise by the underwriters of their option to purchase additional shares of common stock. In addition, immediately prior to the closing of the IPO, all outstanding shares of the Company’s convertible preferred stock automatically converted into 7,064,925 shares of common stock. In connection with the completion of its IPO, on April 20, 2021, the Company’s certificate of incorporation was amended and restated to provide for 300,000,000 authorized shares of common stock with a par value of $0.0001 per share and 10,000,000 authorized shares of preferred stock with a par value of $0.0001 per share. Proceeds from the IPO, net of underwriting discounts and commissions and offering costs, were $152.8 million. Liquidity and Capital Resources The accompanying financial statements have been prepared assuming the Company will continue as a going concern, which assumes the realization of assets and satisfaction of liabilities and commitments in the normal course of business. The Company believes that based on its current operating plan, its cash and cash equivalents, restricted cash, and investments will not enable it to fund its operating expenses and capital expenditure requirements for at least twelve months following the issuance date of the financial statements. The Company's ability to continue as a going concern will require the Company to raise additional capital to fund the Company's operations through public or private equity offering, debt financings, collaborations and licensing arrangements or other sources. There can be no assurance that additional financing will be available to the Company or that such financing, if available, will be available on terms acceptable to the Company. Accordingly, there is substantial doubt about the Company's ability to continue as a going concern. The Company has incurred net operating losses and negative cash flows from operations since its inception and had an accumulated deficit of $131.6 million at December 31, 2022. As of December 31, 2022, the Company had cash, cash equivalents, restricted cash, and investments of $113.4 million. The Company has historically financed its operations primarily through the sale of convertible preferred stock and common stock and the issuance of unsecured promissory notes. To date, none of the Company’s product candidates have been approved for sale, and the Company has not generated any revenue since inception. Management expects operating losses to continue and increase for the foreseeable future, as the Company progresses into clinical development activities for its lead product candidate and advances the preclinical and clinical development of other product candidates. The Company’s prospects are subject to risks, expenses and uncertainties frequently encountered by companies in the biotechnology industry. Failure to generate sufficient cash flows from operations or raise additional capital would have a material adverse effect on the Company’s ability to achieve its intended business objectives.

Organization

12 Months Ended

Dec. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Note 1. Organization

Organization

Biomea Fusion, Inc., (the Company), was established in the state of Delaware in August 2017 as Biomea Fusion, LLC. In December 2020, all outstanding membership interests in Biomea Fusion, LLC were converted into equity interests in the Company. The capitalization information included in these financial statements is consistently presented as if it is that of Biomea Fusion, Inc., even during the prior period when investors held their equity interests in Biomea Fusion, LLC.

The Company is a clinical-stage biopharmaceutical company dedicated to discovering and developing novel covalent small molecules to treat and improve the lives of patients with genetically defined cancers and metabolic diseases. Since its inception in 2017, the Company has built its proprietary FUSIONTM System platform to design and develop a pipeline of novel covalent product candidates.

Forward Stock Split

In April 2021, the Company’s board of directors approved an amended and restated certificate of incorporation to effect a split of shares of the Company’s outstanding capital at a ratio of 8.84-for-1 (the Forward Stock Split) effective as of April 12, 2021. The number of authorized shares and the par values of the common stock and convertible preferred stock were not adjusted as a result of the Forward Stock Split. All references to common stock, options to purchase common stock, convertible preferred stock, share data, per share data and related information contained in the financial statements have been retrospectively adjusted to reflect the effect of the Forward Stock Split for all periods presented.

Initial Public Offering

On April 16, 2021, the Company’s registration statement on Form S-1 (File No. 333-254793) relating to its initial public offering (IPO) of common stock became effective. The IPO closed on April 20, 2021 at which time the Company issued an aggregate of 9,000,000 shares of its common stock at a price of $17.00 per share. Subsequent to the close, an additional 823,532 shares were issued in connection with the partial exercise by the underwriters of their option to purchase additional shares of common stock. In addition, immediately prior to the closing of the IPO, all outstanding shares of the Company’s convertible preferred stock automatically converted into 7,064,925 shares of common stock. In connection with the completion of its IPO, on April 20, 2021, the Company’s certificate of incorporation was amended and restated to provide for 300,000,000 authorized shares of common stock with a par value of $0.0001 per share and 10,000,000 authorized shares of preferred stock with a par value of $0.0001 per share. Proceeds from the IPO, net of underwriting discounts and commissions and offering costs, were $152.8 million.

Liquidity and Capital Resources

The accompanying financial statements have been prepared assuming the Company will continue as a going concern, which assumes the realization of assets and satisfaction of liabilities and commitments in the normal course of business. The Company believes that based on its current operating plan, its cash and cash equivalents, restricted cash, and investments will not enable it to fund its operating expenses and capital expenditure requirements for at least twelve months following the issuance date of the financial statements. The Company's ability to continue as a going concern will require the Company to raise additional capital to fund the Company's operations through public or private equity offering, debt financings, collaborations and licensing arrangements or other sources. There can be no assurance that additional financing will be available to the Company or that such financing, if available, will be available on terms acceptable to the Company. Accordingly, there is substantial doubt about the Company's ability to continue as a going concern. The Company has incurred net operating losses and negative cash flows from operations since its inception and had an accumulated deficit of $131.6 million at December 31, 2022. As of December 31, 2022, the Company had cash, cash equivalents, restricted cash, and investments of $113.4 million.

The Company has historically financed its operations primarily through the sale of convertible preferred stock and common stock and the issuance of unsecured promissory notes. To date, none of the Company’s product candidates have been approved for sale, and the Company has not generated any revenue since inception. Management expects operating losses to continue and increase for the foreseeable future, as the Company progresses into clinical development activities for its lead product candidate and advances the preclinical and clinical development of other product candidates. The Company’s prospects are subject to risks, expenses and uncertainties frequently encountered by companies in the biotechnology industry.

Failure to generate sufficient cash flows from operations or raise additional capital would have a material adverse effect on the Company’s ability to achieve its intended business objectives.