Deerfield funds boost Larimar Therapeutics (LRMR) stake with 5M-share open-market buy

Rhea-AI Filing Summary

Larimar Therapeutics, Inc. reported that investment funds managed by Deerfield entities associated with James E. Flynn made significant open-market purchases of its common stock. On February 27, 2026, Deerfield Private Design Fund III, L.P., Deerfield Private Design Fund IV, L.P., Deerfield Healthcare Innovations Fund, L.P., and Deerfield Partners, L.P. collectively bought 5,000,000 shares of Larimar common stock at $5.00 per share in indirect transactions. Following these purchases, each fund reported updated indirect holdings in Larimar, while the reporting persons collectively disclaimed beneficial ownership beyond any indirect pecuniary interest described in the footnotes.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Flynn James E

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Larimar Therapeutics, Inc. [ LRMR ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

3. Date of Earliest Transaction (Month/Day/Year)
02/27/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	02/27/2026		P		1,084,010	A	$5	10,622,928	I	Through Deerfield Private Design Fund III, L.P.(1)(2)
Common Stock	02/27/2026		P		1,084,012	A	$5	10,622,957	I	Through Deerfield Private Design Fund IV, L.P.(1)(2)
Common Stock	02/27/2026		P		831,978	A	$5	8,153,107	I	Through Deerfield Healthcare Innovations Fund, L.P.(1)(2)
Common Stock	02/27/2026		P		2,000,000	A	$5	6,207,982	I	Through Deerfield Partners, L.P.(1)(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person^*

Flynn James E

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

DEERFIELD MANAGEMENT COMPANY, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Mgmt III, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Mgmt HIF, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Mgmt IV, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Mgmt L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Private Design Fund III, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Healthcare Innovations Fund, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

Deerfield Private Design Fund IV, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

1. Name and Address of Reporting Person^*

DEERFIELD PARTNERS, L.P.

(Last) (First) (Middle)

345 PARK AVENUE SOUTH, 12TH FLOOR

(Street)

NEW YORK NY 10010

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)	X	Other (specify below)
			* Director by Deputization

Explanation of Responses:

1. This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt III, L.P. is the general partner of Deerfield Private Design Fund III, L.P. ("Fund III"). Deerfield Mgmt IV, L.P. is the general partner of Deerfield Private Design Fund IV, L.P. ("Fund IV"). Deerfield Mgmt HIF, L.P. is the general partner of Deerfield Healthcare Innovations Fund, L.P. ("Deerfield HIF"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. ("Deerfield Partners"). Deerfield Management Company, L.P. is the investment manager of Deerfield Partners, L.P., Fund III, Fund IV and Deerfield HIF (collectively, the "Funds"). James E. Flynn is the sole manager of the general partner of each of Deerfield Mgmt III, L.P., Deerfield Mgmt IV, L.P., Deerfield Mgmt HIF, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

2. In accordance with Instruction 4 (b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Funds is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

Remarks:

Jonathan S. Leff, a partner in Deerfield Management, serves as a director of the Issuer. Jonathan Isler, Attorney-in-Fact: Power of Attorney, which is hereby incorporated by reference to Exhibit 24 to a Form 3 with regard to BiomX Inc. filed with the Securities and Exchange Commission on March 19, 2024 by Deerfield Private Design Fund V, L.P., Deerfield Healthcare Innovations Fund II, L.P., Deerfield Mgmt V, L.P., Deerfield Mgmt HIF II, L.P., Deerfield Management Company, L.P. and James E. Flynn.

	/s/ Jonathan Isler, Attorney-in-Fact	03/02/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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FAQ

What insider activity did Larimar Therapeutics (LRMR) report in this Form 4?

Larimar Therapeutics reported that several Deerfield investment funds made open-market purchases of its common stock. On February 27, 2026, these funds collectively acquired 5,000,000 LRMR shares at $5.00 per share, increasing their indirect ownership stakes disclosed under Section 16 reporting rules.

Who are the reporting persons in the Larimar Therapeutics (LRMR) Form 4 filing?

The reporting persons include James E. Flynn and multiple Deerfield entities, such as Deerfield Management Company, L.P. and several affiliated funds. They are listed as directors by deputization and ten percent owners, collectively reporting the funds’ positions in Larimar Therapeutics common stock.

Which Deerfield funds bought Larimar Therapeutics (LRMR) shares and how many?

Deerfield Private Design Fund III, L.P., Deerfield Private Design Fund IV, L.P., Deerfield Healthcare Innovations Fund, L.P., and Deerfield Partners, L.P. executed the purchases. Together they acquired 5,000,000 Larimar common shares in open-market transactions at $5.00 per share on February 27, 2026.

What prices were paid for the Larimar Therapeutics (LRMR) shares in the reported transactions?

All reported open-market purchases of Larimar Therapeutics common stock were executed at $5.00 per share. Each of the four Deerfield-affiliated funds bought its respective block of shares at this same price during the February 27, 2026 trading session.

Do the Deerfield reporting persons claim full beneficial ownership of the Larimar (LRMR) shares?

No, the reporting persons expressly disclaim beneficial ownership of the issuer’s securities beyond any indirect pecuniary interest. The Form 4 states that, for Section 16 purposes, they are not admitting beneficial ownership of all shares held by the Deerfield funds in Larimar Therapeutics.

How many Larimar Therapeutics (LRMR) shares did each Deerfield fund hold after the transactions?

After the purchases, Deerfield Private Design Fund III, L.P. reported 10,622,928 shares, Deerfield Private Design Fund IV, L.P. 10,622,957 shares, Deerfield Healthcare Innovations Fund, L.P. 8,153,107 shares, and Deerfield Partners, L.P. 6,207,982 shares, all reported as indirect holdings through the respective funds.