LB PHARMACEUTICALS INC ownership disclosure: Commodore Capital LP, Commodore Capital Master LP, Robert Egen Atkinson and Michael Kramarz report beneficial ownership of 1,972,369 shares of Common Stock as of March 31, 2026, including 1,500,000 shares held and 472,369 shares issuable upon exercise of a Pre-Funded Warrant. Ownership percentages use 28,674,827 shares outstanding as of March 31, 2026 reported in the issuer's Form 10-Q filed May 12, 2026. The Pre-Funded Warrant is subject to a Beneficial Ownership Limitation of 9.99%.
Positive
None.
Negative
None.
Insights
Commodore reports a ~1.97M share position including pre-funded warrants.
Commodore Capital and affiliated entities report beneficial ownership of 1,972,369 shares, comprised of 1,500,000 held shares plus 472,369 shares issuable upon exercise of a Pre-Funded Warrant as of March 31, 2026. The filing bases percentages on 28,674,827 shares outstanding from the issuer's Form 10-Q.
Cash-flow treatment and sale intentions are not disclosed in the excerpt. Future trading by the holders will be constrained by the stated Beneficial Ownership Limitation of 9.99%.
Filing clarifies shared voting/dispositive power and a joint filing agreement.
The report shows shared voting and dispositive power of 1,972,369 shares across Commodore entities and named individuals, and includes a signed Joint Filing Agreement as an exhibit. The managers named (Kramarz and Atkinson) exercise investment discretion for the Firm.
Because the position includes a pre-funded warrant subject to a 9.99% limitation, any exercise or disposition will be governed by that cap; timing and methods of any sales are not stated in the provided excerpt.
Key Figures
Beneficial ownership:1,972,369 sharesHeld shares:1,500,000 sharesWarrant shares issuable:472,369 shares+2 more
5 metrics
Beneficial ownership1,972,369 sharesas of <date>March 31, 2026</date>
Held shares1,500,000 sharesreported held by the filers
Warrant shares issuable472,369 sharesissuable upon exercise of a Pre-Funded Warrant
Shares outstanding28,674,827 sharesreported outstanding as of <date>March 31, 2026</date> in issuer's Form 10-Q
Beneficial Ownership Limit9.99%limitation on the Pre-Funded Warrant
"issuable upon the exercise of a pre-funded warrant"
A pre-funded warrant is a financial instrument that gives the holder the right to buy shares of a company's stock at a set price, with most of the purchase cost already paid upfront. It functions like a nearly fully paid option, allowing investors to secure shares quickly while minimizing the amount of additional money they need to invest later. This helps investors gain ownership rights efficiently, often used to avoid certain regulatory restrictions or to prepare for future stock purchases.
Beneficial Ownership Limitationregulatory
"subject to a beneficial ownership limitation of 9.99%"
A beneficial ownership limitation is a rule that caps the percentage of a company’s shares an investor can be treated as owning or controlling for voting, regulatory or tax purposes. It matters to investors because it can restrict how many shares a person or group can buy or vote, affect takeover chances, and influence share liquidity and value — like a speed limit that prevents any single driver from taking over the whole road.
Schedule 13G/Aregulatory
"This report is being filed by Commodore Capital LP ..."
A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 2)
LB PHARMACEUTICALS INC
(Name of Issuer)
Common Stock, $0.0001 par value per share
(Title of Class of Securities)
50180M108
(CUSIP Number)
03/31/2026
(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)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
50180M108
1
Names of Reporting Persons
Commodore Capital LP
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
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
1,972,369.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,972,369.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,972,369.00
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)
6.8 %
12
Type of Reporting Person (See Instructions)
IA, PN
SCHEDULE 13G
CUSIP Number(s):
50180M108
1
Names of Reporting Persons
Commodore Capital Master LP
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
CAYMAN ISLANDS
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
1,972,369.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,972,369.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,972,369.00
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)
6.8 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP Number(s):
50180M108
1
Names of Reporting Persons
Robert Egen Atkinson
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
0.00
6
Shared Voting Power
1,972,369.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,972,369.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,972,369.00
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)
6.8 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
CUSIP Number(s):
50180M108
1
Names of Reporting Persons
Michael Kramarz
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
0.00
6
Shared Voting Power
1,972,369.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,972,369.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,972,369.00
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)
6.8 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
LB PHARMACEUTICALS INC
(b)
Address of issuer's principal executive offices:
One Pennsylvania Plaza, Suite 1025, New York, NEW YORK, 10119.
Item 2.
(a)
Name of person filing:
Commodore Capital LP
Commodore Capital Master LP
Robert Egen Atkinson
Michael Kramarz
Each a "Filer."
(b)
Address or principal business office or, if none, residence:
The address for Commodore Capital LP, Robert Egen Atkinson, and Michael Kramarz is 444 Madison Avenue, Floor 35, New York, NY 10022.
The address for Commodore Capital Master LP is c/o Maples Corporate Services Limited, Ugland House, South Church Street, PO Box 309, Grand Cayman KY1-1104, Cayman Islands.
(c)
Citizenship:
See Item 4 of the cover page for each Filer.
(d)
Title of class of securities:
Common Stock, $0.0001 par value per share
(e)
CUSIP No.:
50180M108
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
See Item 9 of the cover page for each Filer.
This report on Schedule 13G is being filed by Commodore Capital LP (the "Firm"), Commodore Capital Master LP ("Commodore Master"), Michael Kramarz, and Robert Egen Atkinson. The Firm is the investment manager to Commodore Master. As of March 31, 2026, the Firm may be deemed to beneficially own an aggregate of 1,972,369 shares Common Stock, par value $0.0001 per share (the "Common Stock"), consisting of (i) 1,500,000 shares of the Common Stock, and (ii) 472,369 shares of Common Stock each Filer has the right to acquire through the exercise of a pre-funded warrant ("Pre-Funded Warrant") of LB Pharmaceuticals Inc. (the "Issuer"), which is subject to a beneficial ownership limitation of 9.99% (the "Beneficial Ownership Limitation"). The Firm, as the investment manager to Commodore Master, may be deemed to beneficially own these securities. Michael Kramarz and Robert Egen Atkinson are the managing partners of the Firm and exercise investment discretion with respect to these securities. Ownership percentages are based on 28,674,827 Common Stock reported as issued and outstanding as of March 31, 2026 in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 12, 2026, plus 472,369 shares of Common Stock which the Filers may acquire upon the exercise of the Pre-Funded Warrant, subject to the Beneficial Ownership Limitation.
(b)
Percent of class:
See Item 11 of the cover page for each Filer.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
See Item 5 of the cover page for each Filer.
(ii) Shared power to vote or to direct the vote:
See Item 6 of the cover page for each Filer.
(iii) Sole power to dispose or to direct the disposition of:
See Item 7 of the cover page for each Filer.
(iv) Shared power to dispose or to direct the disposition of:
See Item 8 of the cover page for each Filer.
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
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:
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.
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.
