[SCHEDULE 13G/A] Biomea Fusion, Inc. Amended Passive Investment Disclosure

Rhea-AI Filing Summary

Rainer M. Erdtmann filed an amended Schedule 13G reporting beneficial ownership of 2,782,707 shares of Biomea Fusion, Inc. common stock, representing 3.9% of the class as of the measurement date. The holdings include directly owned shares, stock options exercisable within 60 days, and shares held by his children and two independent trusts.

The ownership percentage is based on 70,703,639 shares outstanding as of October 31, 2025, plus 690,677 option shares exercisable within 60 days after December 31, 2025. Erdtmann also notes he resigned on December 19, 2025 from Point Sur Investors’ general partner and is no longer deemed a beneficial owner of securities held by those entities.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)

Biomea Fusion, Inc.

(Name of Issuer)

Common Stock, $0.0001 par value

(Title of Class of Securities)

09077A106

(CUSIP Number)

12/31/2025

(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)

SCHEDULE 13G

CUSIP No. 09077A106

1

Names of Reporting Persons

Rainer M. Erdtmann

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 2,782,707.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 2,782,707.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,782,707.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

3.9 %

12

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Biomea Fusion, Inc.
(b)	Address of issuer's principal executive offices: 1599 Industrial Road, San Carlos, CA 94070
Item 2.
(a)	Name of person filing: This statement is filed by Rainer M. Erdtmann, a citizen of the United States of America, with respect to the shares of common stock of Biomea Fusion, Inc. (the "Company"), par value $0.0001 per share (the "Shares").
(b)	Address or principal business office or, if none, residence: The address of the principal business office of Rainer M. Erdtmann is c/o Biomea Fusion, Inc., 1599 Industrial Road, San Carlos, CA 94070.
(c)	Citizenship: See Item 2(a) above.
(d)	Title of class of securities: Common Stock, $0.0001 par value
(e)	CUSIP No.: 09077A106
Item 4.	Ownership
(a)	Amount beneficially owned: Rainer M. Erdtmann may be deemed to beneficially own 2,782,707 Shares, consisting of: (i) 690,677 Shares issuable upon the exercise of stock options exercisable within 60 days held directly by Rainer M. Erdtmann, (ii) 572,427 shares held directly by Rainer M. Erdtmann, (iii) an aggregate of 210,000 Shares held by the children of Rainer M. Erdtmann, (iv) 174,614 Shares held by a trust with an independent trustee ("Trust 1"); and (v) 1,134,989 Shares held by a separate trust with an independent trustee ("Trust 2"). Effective December 19, 2025, the Reporting Person resigned as a Managing Member of Point Sur Investors, LLC, the general partner of Point Sur Investors Fund I, LP and no longer may be deemed a beneficial owner of any of the Issuer's securities held directly by Point Sur Investors Fund I, LP and Point Sur Investors, LLC.
(b)	Percent of class: The percent of class of the outstanding Shares beneficially owned by the Reporting Person in Item 4(a) is based on (i) 70,703,639 shares of Common Stock outstanding as of October 31, 2025, as disclosed in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on November 4, 2025 and (ii) 690,677 Shares issuable within 60 days after December 31, 2025 upon the exercise of options held directly by Rainer M. Erdtmann, which have been added to the Shares reported as outstanding in accordance with Rule 13d-3(d)(1)(i) under the Securities Exchange Act of 1934.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: The information required by this Item 4(c)(i) is set forth in Row 5 of the cover page for the Reporting Person hereto and is incorporated herein by reference for the Reporting Person.
	(ii) Shared power to vote or to direct the vote: The information required by this Item 4(c)(ii) is set forth in Row 6 of the cover page for the Reporting Person hereto and is incorporated herein by reference for the Reporting Person.
	(iii) Sole power to dispose or to direct the disposition of: The information required by this Item 4(c)(iii) is set forth in Row 7 of the cover page for the Reporting Person hereto and is incorporated herein by reference for the Reporting Person.
	(iv) Shared power to dispose or to direct the disposition of: The information required by this Item 4(c)(iv) is set forth in Row 8 of the cover page for the Reporting Person hereto and is incorporated herein by reference for the Reporting Person.
Item 5.	Ownership of 5 Percent or Less of a Class.
	Ownership of 5 percent or less of a class
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
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
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.	Certifications:
	Not Applicable

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.

Rainer M. Erdtmann

Signature:	/s/ Rainer M. Erdtmann
Name/Title:	Rainer M. Erdtmann
Date:	02/06/2026

FAQ

What stake does Rainer M. Erdtmann report in Biomea Fusion (BMEA)?

Rainer M. Erdtmann reports beneficial ownership of 2,782,707 Biomea Fusion shares, or 3.9% of the class. This total includes directly held shares, stock options exercisable within 60 days, and shares held by his children and two independent trusts.

How is the 3.9% ownership in Biomea Fusion (BMEA) calculated?

The 3.9% ownership is based on 70,703,639 shares outstanding plus 690,677 option shares. The outstanding shares figure comes from Biomea Fusion’s Form 10-Q as of October 31, 2025, with additional shares from options exercisable within 60 days after December 31, 2025.

What types of Biomea Fusion (BMEA) holdings does Rainer M. Erdtmann report?

The reported holdings include direct shares, stock options, and shares held by related parties and trusts. Specifically, they comprise direct ownership, options exercisable within 60 days, shares held by his children, and shares in two trusts with independent trustees.

Did Rainer M. Erdtmann change any affiliations affecting his Biomea Fusion (BMEA) ownership?

Yes. Effective December 19, 2025, he resigned as a managing member of Point Sur Investors, LLC. As a result, he is no longer deemed a beneficial owner of Biomea Fusion securities held directly by Point Sur Investors Fund I, LP and Point Sur Investors, LLC.

Does Rainer M. Erdtmann report sole or shared voting power over Biomea Fusion (BMEA) shares?

He reports sole voting and dispositive power over 2,782,707 Biomea Fusion shares, with no shared power. The cover page shows sole voting power and sole dispositive power for the entire reported beneficial ownership amount.