# EDGAR Filing Document

**Accession Number:** 0001691082
**File Stem:** 0002015536-25-000007
**Filing Date:** 2025-9
**Character Count:** 10783
**Document Hash:** bd2dcc1bcf41ba0d1f33103b640aa8fc
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0002015536-25-000007.hdr.sgml**: 20250916

**ACCESSION NUMBER**: 0002015536-25-000007

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250912

**FILED AS OF DATE**: 20250916

**DATE AS OF CHANGE**: 20250916

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** KROIN DAVID
- **CENTRAL INDEX KEY:** 0001397513

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42831
- **FILM NUMBER:** 251318310

**MAIL ADDRESS:**
- **STREET 1:** C/O DEEP TRACK CAPITAL, LP
- **STREET 2:** 200 GREENWICH AVENUE, 3RD FLOOR
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Deep Track Biotechnology Master Fund, Ltd.
- **CENTRAL INDEX KEY:** 0002015536

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42831
- **FILM NUMBER:** 251318311

**BUSINESS ADDRESS:**
- **STREET 1:** C/O WALKERS CORPORATE LIMITED
- **STREET 2:** 190 ELGIN AVE
- **CITY:** GEORGE TOWN
- **STATE:** E9
- **ZIP:** KY1-9001
- **BUSINESS PHONE:** 203-409-0810

**MAIL ADDRESS:**
- **STREET 1:** C/O WALKERS CORPORATE LIMITED
- **STREET 2:** 190 ELGIN AVE
- **CITY:** GEORGE TOWN
- **STATE:** E9
- **ZIP:** KY1-9001
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Deep Track Capital, LP
- **CENTRAL INDEX KEY:** 0001856083

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42831
- **FILM NUMBER:** 251318312

**BUSINESS ADDRESS:**
- **STREET 1:** 200 GREENWICH AVENUE
- **STREET 2:** 3RD FLOOR
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830
- **BUSINESS PHONE:** 2034090812

**MAIL ADDRESS:**
- **STREET 1:** 200 GREENWICH AVENUE
- **STREET 2:** 3RD FLOOR
- **CITY:** GREENWICH
- **STATE:** CT
- **ZIP:** 06830
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** LB PHARMACEUTICALS INC
- **CENTRAL INDEX KEY:** 0001691082
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 575 MADISON AVENUE
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10022
- **BUSINESS PHONE:** 917-450-6581

**MAIL ADDRESS:**
- **STREET 1:** 575 MADISON AVENUE
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10022

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** LB PHARMACEUTICALS INC.
- **DATE OF NAME CHANGE:** 20161129

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

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] 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**<sup>*</sup><br>Deep Track Biotechnology Master Fund, Ltd.<br><sub>(Last) (First) (Middle)</sub><br>C/O WALKERS CORPORATE LIMITED<br>190 ELGIN AVE<br><sub>(Street)</sub><br>GEORGE TOWN, E9 KY1-9001<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2025-09-12 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>LB PHARMACEUTICALS INC [ LBRX ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Deep Track Capital, LP<br><sub>(Last) (First) (Middle)</sub><br>200 GREENWICH AVE, 3RD FLOOR<br><sub>(Street)</sub><br>GREENWICH, CT 06830<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2025-09-12 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>LB PHARMACEUTICALS INC [ LBRX ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>KROIN DAVID<br><sub>(Last) (First) (Middle)</sub><br>C/O DEEP TRACK CAPITAL, LP<br>200 GREENWICH AVE, 3RD FLOOR<br><sub>(Street)</sub><br>GREENWICH, CT 06830<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2025-09-12 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>LB PHARMACEUTICALS INC [ LBRX ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2025-09-12 |  | C |  | 686138 | A | <sup>(1)</sup> | 686138 | D<sup>(2)</sup> |  |
| Common Stock | 2025-09-12 |  | P |  | 2000000 | A | $15 | 2686138 | D<sup>(2)</sup> |  |
| Common Stock | 2025-09-12 |  | P |  | 666666 | A | $15 | 666666 | I | By Deep Track Special Opportunities Fund, LP<sup>(3)</sup> |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Series C Preferred Stock | <sup>(1)</sup> | 2025-09-12 |  | C |  |  | 16666667 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 686138 | <sup>(1)</sup> | 0 | D<sup>(2)</sup> |  |

---

### Footnotes:

(1) Each share of Series C Preferred Stock automatically converted immediately prior to the closing of the Issuer's initial public offering for no additional consideration at a conversion ratio that was dependent upon the initial price per share to the public in the Issuer's initial public offering.

(2) Represents securities held by Deep Track Biotechnology Master Fund, Ltd. Deep Track Capital, LP is the investment manager of Deep Track Biotechnology Master Fund, Ltd. Mr. David Kroin is the managing member of Deep Track Capital GP, LLC, the general partner of Deep Track Capital, LP., and by virtue of such status may be deemed to be the beneficial owner of the shares owned by Deep Track Biotechnology Master Fund, Ltd. Deep Track Capital, LP and Mr. Kroin disclaim beneficial ownership of such shares except to the extent of their respective pecuniary interests.

(3) Represents securities held by Deep Track Special Opportunities Fund, LP.   Deep Track Capital, LP is the investment manager of Deep Track Special Opportunities Fund LP. Mr. David Kroin is the managing member of Deep Track Capital GP, LLC, the general partner of Deep Track Capital, LP., and by virtue of such status may be deemed to be the beneficial owner of the shares owned by Deep Track Special Opportunities Fund, LP. Deep Track Capital, LP and Mr. Kroin disclaim beneficial ownership of such shares except to the extent of their respective pecuniary interests.

**Signature:** Deep Track Biotechology Master Fund, Ltd. /s/ David Kroin, Director  
**Date:** 2025-09-16

**Signature:** Deep Track Capital, LP /s/ David Kroin, Managing Member of the General Partner of the Investment Adviser  
**Date:** 2025-09-16

**Signature:** /s/ David Kroin  
**Date:** 2025-09-16

### Remarks:

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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**