# EDGAR Filing Document

**Accession Number:** 0001860059
**File Stem:** 0001193125-26-085888
**Filing Date:** 2026-3
**Character Count:** 24696
**Document Hash:** 221d95fbc8c6e1c64b72f467521412d0
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-085888.hdr.sgml**: 20260302

**ACCESSION NUMBER**: 0001193125-26-085888

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260226

**FILED AS OF DATE**: 20260302

**DATE AS OF CHANGE**: 20260302

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** AFEYAN NOUBAR
- **CENTRAL INDEX KEY:** 0001222012

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709868

**MAIL ADDRESS:**
- **STREET 1:** C/O FLAGSHIP PIONEERING
- **STREET 2:** 55 CAMBRIDGE PARKWAY, SUITE 800E
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Flagship Pioneering, LLC
- **CENTRAL INDEX KEY:** 0001400240

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709867

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY, SUITE 800E
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617 868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY, SUITE 800E
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142

**FORMER NAME:**
- **FORMER CONFORMED NAME:** Flagship Pioneering Inc.
- **DATE OF NAME CHANGE:** 20170210

**FORMER NAME:**
- **FORMER CONFORMED NAME:** Flagship Ventures Management, Inc.
- **DATE OF NAME CHANGE:** 20070522
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Flagship Pioneering Fund VI General Partner LLC
- **CENTRAL INDEX KEY:** 0001724957

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709865

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** SUITE 800E
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** SUITE 800E
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Nutritional Health LTP Fund General Partner LLC
- **CENTRAL INDEX KEY:** 0001780951

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

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709863

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY, 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY, 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Flagship Pioneering Fund VII General Partner LLC
- **CENTRAL INDEX KEY:** 0001805917

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

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709864

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142

**FORMER NAME:**
- **FORMER CONFORMED NAME:** Flagship Pioneering - Origination Fund VII General Partner LLC
- **DATE OF NAME CHANGE:** 20200309
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Flagship Pioneering Special Opportunities Fund II General Partner LLC
- **CENTRAL INDEX KEY:** 0001826217

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

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709862

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** FPN General Partner LLC
- **CENTRAL INDEX KEY:** 0001860059

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

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709861

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Flagship VentureLabs VI Manager LLC
- **CENTRAL INDEX KEY:** 0001860060

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

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43165
- **FILM NUMBER:** 26709866

**BUSINESS ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-868-1888

**MAIL ADDRESS:**
- **STREET 1:** 55 CAMBRIDGE PARKWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Generate Biomedicines, Inc.
- **CENTRAL INDEX KEY:** 0002100782
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 831630228
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 101 SOUTH STREET, SUITE 900
- **CITY:** SOMERVILLE
- **STATE:** MA
- **ZIP:** 02143
- **BUSINESS PHONE:** 888-469-0055

**MAIL ADDRESS:**
- **STREET 1:** 101 SOUTH STREET, SUITE 900
- **CITY:** SOMERVILLE
- **STATE:** MA
- **ZIP:** 02143

### 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>AFEYAN NOUBAR<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Generate Biomedicines, Inc. [ GENB ] | **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>Flagship Pioneering, LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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>Flagship VentureLabs VI Manager LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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>Flagship Pioneering Fund VI General Partner LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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>Flagship Pioneering Fund VII General Partner LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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>Nutritional Health LTP Fund General Partner LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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>Flagship Pioneering Special Opportunities Fund II General Partner LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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>FPN General Partner LLC<br><sub>(Last) (First) (Middle)</sub><br>55 CAMBRIDGE PARKWAY, SUITE 800E<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02142<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-26 | **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>Generate Biomedicines, Inc. [ GENB ] | **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 | 2026-03-02 |  | C |  | 12723940 | A | <sup>(1)</sup> | 12723940 | I | By Flagship Pioneering Fund VI, L.P.<sup>(2)</sup> |
| Common Stock | 2026-03-02 |  | C |  | 13702224 | A | <sup>(1)</sup> | 13702224 | I | By Flagship Pioneering Fund VII, L.P.<sup>(3)</sup> |
| Common Stock | 2026-03-02 |  | C |  | 987491 | A | <sup>(1)</sup> | 987491 | I | By Nutritional Health LTP Fund, L.P.<sup>(4)</sup> |
| Common Stock | 2026-03-02 |  | C |  | 2777752 | A | <sup>(1)</sup> | 2777752 | I | By Flagship Pioneering Special Opportunities Fund II, L.P.<sup>(5)</sup> |
| Common Stock | 2026-03-02 |  | C |  | 2777752 | A | <sup>(1)</sup> | 2777752 | I | By FPN II, L.P.<sup>(6)</sup> |
| Common Stock | 2026-03-02 |  | P |  | 1562500 | A | $16 | 15264724 | I | By Flagship Pioneering Fund VII, L.P.<sup>(3)</sup> |
| Common Stock | 2026-03-02 |  | P |  | 1562500 | A | $16 | 4340252 | I | By FPN II, L.P.<sup>(6)</sup> |
| Common Stock | 2026-03-02 |  | P |  | 1562500 | A | $16 | 1562500 | I | By Pioneering Medicines 02, LLC<sup>(7)</sup> |
| Common Stock |  |  |  |  |  |  |  | 25016458 | I | By Flagship VentureLabs VI, LLC<sup>(8)</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 |
| Stock Option (Right to Buy) | $16 | 2026-02-26 |  | A |  | 29561 |  | <sup>(9)</sup> | 2036-02-25 | Common Stock | 29561 | $0 | 29561 | D |  |
| Series A Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 18483785 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 12168390 | $0 | 0 | I | By Flagship Pioneering Fund VI, L.P.<sup>(2)</sup> |
| Series A Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 17016215 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 11202248 | $0 | 0 | I | By Flagship Pioneering Fund VII, L.P.<sup>(3)</sup> |
| Series A Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 1500000 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 987491 | $0 | 0 | I | By Nutritional Health LTP Fund, L.P.<sup>(4)</sup> |
| Series B Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 843881 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 555550 | $0 | 0 | I | By Flagship Pioneering Fund VI, L.P.<sup>(2)</sup> |
| Series B Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 1265822 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 833325 | $0 | 0 | I | By Flagship Pioneering Fund VII, L.P.<sup>(3)</sup> |
| Series B Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 2953586 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 1944427 | $0 | 0 | I | By Flagship Pioneering Special Opportunities Fund II, L.P.<sup>(5)</sup> |
| Series B Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 2109704 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 1388876 | $0 | 0 | I | By FPN II, L.P.<sup>(6)</sup> |
| Series C Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 2531644 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 1666651 | $0 | 0 | I | By Flagship Pioneering Fund VII, L.P.<sup>(3)</sup> |
| Series C Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 1265822 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 833325 | $0 | 0 | I | By Flagship Pioneering Special Opportunities Fund II, L.P.<sup>(5)</sup> |
| Series C Preferred Stock | <sup>(1)</sup> | 2026-03-02 |  | C |  |  | 2109704 | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 1388876 | $0 | 0 | I | By FPN II, L.P.<sup>(6)</sup> |

---

### Footnotes:

(1) Securities held by Flagship Pioneering Fund VI, L.P. ("Flagship Fund VI"). Flagship Pioneering Fund VI General Partner LLC ("Flagship Fund VI GP") is the general partner of Flagship Fund VI. Flagship Pioneering, LLC ("Flagship Pioneering") is the manager of Flagship Fund VI GP. Noubar B. Afeyan, Ph.D. is the ultimate control person of Flagship Pioneering. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(2) Each share of Series A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock (collectively, the "Preferred Stock") automatically converted into shares of the Issuer's Common Stock on a one-for-1.5190 basis upon the closing of the Issuer's initial public offering on March 2, 2026. The Preferred Stock had no expiration date.

(3) Securities held by Flagship Pioneering Fund VII, L.P. ("Flagship Fund VII"). Flagship Pioneering Fund VII General Partner LLC ("Flagship Fund VII GP") is the general partner of Flagship Fund VII. Flagship Pioneering is the manager of Flagship Fund VII GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(4) Securities held by Nutritional Health LTP Fund, L.P. ("Nutritional LTP"). Nutritional Health LTP Fund General Partner LLC ("Nutritional LTP GP") is the general partner of Nutritional LTP. Flagship Pioneering is the manager of Nutritional LTP GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(5) Securities held by Flagship Pioneering Special Opportunities Fund II, L.P. ("Flagship Opportunities Fund II"). Flagship Pioneering Special Opportunities Fund II General Partner LLC ("Flagship Opportunities Fund II GP") is the general partner of Flagship Opportunities Fund II. Flagship Pioneering is the manager of Flagship Opportunities Fund II GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(6) Securities held by FPN II, L.P. ("FPN II Fund"). FPN General Partner LLC ("FPN GP") is the general partner of FPN II Fund. Flagship Pioneering is the manager of FPN GP. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(7) Securities held by Pioneering Medicine 02, LLC ("PM02"). Charles R. Carelli, Jr., Chief Financial Officer of Flagship Pioneering, is the sole manager of PM02, and Flagship Fund VII is its majority equity holder. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(8) Securities held by Flagship VentureLabs VI LLC ("VentureLabs VI"). Flagship VentureLabs VI Manager LLC ("VentureLabs VI Manager") is the manager of VentureLabs VI. Flagship Pioneering is the manager of VentureLabs VI Manager. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any.

(9) The shares underlying this option shall vest in full on February 19, 2027, subject to the Reporting Person's continued service on such vesting date.

**Remarks:**
Form 2 of 2: This is the second of two Forms 4 being filed relating to the same event. The Form 4 is being split into two filings because there are more than 10 Reporting Persons in total, and the SEC's EDGAR filing system limits a single Form 4 to a maximum of 10 Reporting Persons. Each Form 4 is filed by Designated Filer Noubar Afeyan.

**Signature:** /s/ Noubar B. Afeyan, Ph.D.  
**Date:** 2026-03-02

**Signature:** Flagship Pioneering, LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager  
**Date:** 2026-03-02

**Signature:** Flagship VentureLabs VI Manager LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager  
**Date:** 2026-03-02

**Signature:** Flagship Pioneering Fund VI General Partner LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager  
**Date:** 2026-03-02

**Signature:** Flagship Pioneering Fund VII General Partner LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager  
**Date:** 2026-03-02

**Signature:** Nutritional Health LTP Fund General Partner LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager  
**Date:** 2026-03-02

**Signature:** Flagship Pioneering Special Opportunities Fund II General Partner LLC, By: /s/ Noubar B. Afeyan Ph.D., Title: Sole Member and Manager of Manager of Manager  
**Date:** 2026-03-02

**Signature:** FPN General Partner LLC, By: /s/ Noubar B. Afeyan, Ph.D., Title: Sole Member and Manager of Manager of Manager  
**Date:** 2026-03-02

### 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.

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