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 Estimated average burden hours per response: 0.5
X	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* Vida Ventures GP III, L.L.C. (Last) (First) (Middle) 10100 SANTA MONICA BOULEVARD SUITE 1500 (Street) LOS ANGELES CA 90067 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol LB PHARMACEUTICALS INC [ LBRX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 09/12/2025
	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	09/12/2025		C(1)		547,648	A	(1)	547,648	I	By Vida Ventures III, L.P.(2)(3)
Common Stock	09/12/2025		C(1)		1,262	A	(1)	1,262	I	By Vida Ventures III-A, L.P.(4)
Common Stock	09/12/2025		P		332,566	A	$15	880,214	I	By Vida Ventures III, L.P.(2)(3)
Common Stock	09/12/2025		P		767	A	$15	2,029	I	By Vida Ventures III-A, L.P.(4)
Common Stock								1,434	I	By Vida Ventures Management Co. LLC(5)

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
Series C Preferred Stock	(1)	09/12/2025		C			13,302,666	(1)	(1)	Common Stock	547,648	$0	0	I	By Vida Ventures III, L.P.(2)(3)
Series C Preferred Stock	(1)	09/12/2025		C			30,667	(1)	(1)	Common Stock	1,262	$0	0	I	By Vida Ventures III-A, L.P.(4)

1. Name and Address of Reporting Person* Vida Ventures GP III, L.L.C. (Last) (First) (Middle) 10100 SANTA MONICA BOULEVARD SUITE 1500 (Street) LOS ANGELES CA 90067 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Vida Ventures III, L.P. (Last) (First) (Middle) 10100 SANTA MONICA BOULEVARD SUITE 1500 (Street) LOS ANGELES CA 90067 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Vida Ventures III-A, L.P. (Last) (First) (Middle) 10100 SANTA MONICA BOULEVARD SUITE 1500 (Street) LOS ANGELES CA 90067 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Belldegrun Arie (Last) (First) (Middle) 10100 SANTA MONICA BOULEVARD SUITE 1500 (Street) LOS ANGELES CA 90067 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Vida Ventures Management Co. LLC (Last) (First) (Middle) 10100 SANTA MONICA BOULEVARD SUITE 1500 (Street) LOS ANGELES CA 90067 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Each share of Series C Preferred Stock has no expiration date and converted automatically into Common Stock immediately prior to the Issuer's initial public offering at a conversion ratio based upon the initial price per share to the public in the Issuer's initial public offering.

2. These shares are held directly by Vida Ventures III, L.P. ("Vida III"). Vida Ventures GP III, L.L.C. ("Vida III GP") is the general partner of Vida III and may be deemed to have voting, investment, and dispositive power with respect to these securities. Arie Belldegrun, Helen Kim and Rajul Jain, are the members of the investment committee of Vida III GP (each, an "Investment Committee Member" and such committee, the "Investment Committee").

3. (Continued from Footnote 2) The Investment Committee and each of the Investment Committee Members may be deemed to share voting, investment and dispositive power with respect to these securities. Vida III GP, the Investment Committee and each of the Investment Committee Members disclaims beneficial ownership of the securities held of record by Vida III, and this report shall not be deemed an admission that they are the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their pecuniary interest therein, if any.

4. These shares are held directly by Vida Ventures III-A, L.P. ("Vida III-A"). Vida III GP is the general partner of Vida III-A and may be deemed to have voting, investment, and dispositive power with respect to these securities. The Investment Committee and each of the Investment Committee Members may be deemed to share voting, investment and dispositive power with respect to these securities. Vida III GP, the Investment Committee and each of the Investment Committee Members disclaims beneficial ownership of the securities held of record by Vida III-A, and this report shall not be deemed an admission that they are the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their pecuniary interest therein, if any.

5. These shares are held directly by Vida Ventures Management Co., LLC ("Vida Management"). Each Investment Committee Member (as defined below) disclaims beneficial ownership of the securities held of record by Vida Management, and this report shall not be deemed an admission that they are the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their pecuniary interest therein, if any.

	VIDA VENTURES GP III, L.L.C., By: /s/ Jean-Philippe Kouakou-Zebouah, its Managing Member	09/16/2025
	VIDA VENTURES III, L.P., By: Vida Ventures GP III, L.L.C., its general partner, By: /s/ Jean-Philippe Kouakou-Zebouah, its Managing Member	09/16/2025
	VIDA VENTURES III-A, L.P., By: Vida Ventures GP III, L.L.C., its general partner, By: /s/ Jean-Philippe Kouakou-Zebouah, its Managing Member	09/16/2025
	VIDA VENTURES MANAGEMENT CO., LLC, By: /s/ Jean-Philippe Kouakou-Zebouah, its Managing Member	09/16/2025
	ARIE BELLDEGRUN By: /s/ Jean-Philippe Kouakou-Zebouah, his attorney-in-fact	09/16/2025
	HELEN KIM By: /s/ Jean-Philippe Kouakou-Zebouah, her attorney-in-fact	09/16/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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