UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No.     )*

Biomea Fusion, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

09077A106

(CUSIP Number)

April 20, 2021

(Date of Event which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 09077A106

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CUSIP No. 09077A106

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CUSIP No. 09077A106

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CUSIP No. 09077A106

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CUSIP No. 09077A106

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Item 1(a). Name of Issuer:

Biomea Fusion, Inc. (the “Issuer”)

Item 1(b). Address of Issuer’s Principal Executive Offices:

726 Main Street

Redwood City, California 94063

Item 2(a). Name of Person Filing:

This Schedule 13G is jointly filed by Boxer Capital, LLC (“Boxer Capital”), Boxer Asset Management Inc. (“Boxer Management”), Joe Lewis, MVA Investors, LLC (“MVA Investors”) and Aaron I. Davis (together with Boxer Capital, Boxer Management, Joe Lewis and MVA Investors, the “Reporting Persons”). Boxer Management is the managing member and majority owner of Boxer Capital. Joe Lewis is the sole indirect beneficial owner of and controls Boxer Management. MVA Investors is the independent, personal investment vehicle of certain employees of Boxer Capital, and is controlled by employees of Boxer Capital that are members of MVA Investors. Aaron I. Davis is a member of and has voting and dispositive power over securities held by MVA Investors.

Item 2(b). Address of Principal Business Office, or, if none, Residence:

The principal business address of Boxer Capital, MVA Investors and Aaron Davis is: 12860 El Camino Real, Suite 300, San Diego, CA 92130. The principal business address of Boxer Management and Joe Lewis is: Cay House, EP Taylor Drive N7776, Lyford Cay, New Providence, Bahamas.

Item 2(c). Citizenship:

Boxer Capital is a limited liability company organized under the laws of Delaware. Boxer Management is a corporation organized under the laws of the Bahamas. MVA Investors is a limited liability company organized under the laws of Delaware. Joe Lewis is a citizen of the United Kingdom and Aaron I. Davis is a citizen of the United States.

Item 2(d). Title of Class of Securities:

Common stock, par value $0.0001 per share (the “Common Stock”)

Item 2(e). CUSIP Number:

09077A106

Item 3. If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

Not applicable.

Boxer Capital, Boxer Management and Joe Lewis beneficially own 2,088,405 shares of Common Stock. MVA Investors and Aaron I. Davis beneficially own 73,186 shares of Common Stock. The Reporting Persons beneficially own, in the aggregate, 2,161,591 shares of Common Stock.

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The number of shares of Common Stock beneficially owned by Boxer Capital, Boxer Management and Joe Lewis represents 7.3% of the Issuer’s outstanding Common Stock. The number of shares of Common Stock beneficially owned by MVA Investors and Aaron I. Davis represents 0.3% of the Issuer’s outstanding Common Stock. The number of shares of Common Stock beneficially owned by the Reporting Persons represent, in the aggregate, represents 7.5% of the Issuer’s outstanding Common Stock. All percentages are based on 28,767,867 shares of Common Stock outstanding after the Issuer’s initial public offering, as set forth in the Final Prospectus, assuming no exercise of the underwriters’ option to purchase an additional 1,350,000 shares of Common Stock within 30 days of the date of the Final Prospectus.

None of the Reporting Persons has sole power to vote or to direct the vote of any shares of Common Stock.

Boxer Capital, Boxer Asset Management and Joe Lewis have shared power to vote or to direct the vote of the 2,088,405 shares of Common Stock they beneficially own. MVA Investors and Aaron I. Davis have shared power to vote or to direct the vote of the 73,186 shares of Common Stock they beneficially own.

None of the Reporting Persons has sole power to dispose or to direct the disposition of any shares of Common Stock.

Boxer Capital, Boxer Asset Management and Joe Lewis have shared power to dispose or to direct the disposition of the 2,088,405 shares of Common Stock they beneficially own. MVA Investors and Aaron I. Davis have shared power to dispose or to direct the disposition of the 73,186 shares of Common Stock they beneficially own.

Item 5. Ownership of Five Percent or Less of a Class.

Not applicable.

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

Only Boxer Capital has the right to receive dividends and the proceeds from the sale of the shares of Common Stock held by Boxer Capital. Only MVA Investors has the right to receive dividends and the proceeds from the sale of the shares of Common Stock held by MVA Investors.

Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not applicable.

Item 8. Identification and Classification of Members of the Group.

Not applicable.

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Not applicable.

Item 10. Certification.

(c) By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

Exhibits

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

April 30, 2021

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Exhibit 1

JOINT FILING AGREEMENT

The undersigned hereby agree that the Statement on Schedule 13G with respect to the common stock of Biomea Fusion, Inc., par value $0.0001 per share, is, and any amendments thereto executed by each of us shall be, filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, and that this Agreement shall be included as an Exhibit to the Schedule 13G and each such amendment. Each of the undersigned agrees to be responsible for the timely filing of the Schedule 13G and any amendments thereto, and for the completeness and accuracy of the information concerning itself contained therein. This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of April 30, 2021.