# EDGAR Filing Document

**Accession Number:** 0001346824
**File Stem:** 0001346824-25-000037
**Filing Date:** 2025-11
**Character Count:** 17758
**Document Hash:** 51afd980c8020722c061543ea6ef8bd3
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001346824-25-000037.hdr.sgml**: 20251103

**ACCESSION NUMBER**: 0001346824-25-000037

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20251103

**DATE AS OF CHANGE**: 20251103

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** 89bio, Inc.
- **CENTRAL INDEX KEY:** 0001785173
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 831114349
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-91200
- **FILM NUMBER:** 251444796

**BUSINESS ADDRESS:**
- **STREET 1:** 655 MONTGOMERY STREET
- **STREET 2:** SUITE 1500
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94111
- **BUSINESS PHONE:** (415) 432-9270

**MAIL ADDRESS:**
- **STREET 1:** 655 MONTGOMERY STREET
- **STREET 2:** SUITE 1500
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94111
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** RA CAPITAL MANAGEMENT, L.P.
- **CENTRAL INDEX KEY:** 0001346824

**ORGANIZATION NAME:**
- **EIN:** 830406777
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A

**BUSINESS ADDRESS:**
- **STREET 1:** 200 BERKELEY STREET, 18TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02116
- **BUSINESS PHONE:** 617-778-2500

**MAIL ADDRESS:**
- **STREET 1:** 200 BERKELEY STREET, 18TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02116

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** RA CAPITAL MANAGEMENT, LLC
- **DATE OF NAME CHANGE:** 20051213

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

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 14)**

**89BIO, INC.**

*(Name of Issuer)*

**Common Stock, par value $0.001 per share**

*(Title of Class of Securities)*

**282559103**

*(CUSIP Number)*

**Peter Kolchinsky**<br>RA Capital Management, L.P.<br>200 Berkeley Street, 18th Floor<br>Boston MA 02116<br>617.778.2500

*(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)*

**10/30/2025**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **282559103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**RA Capital Management, L.P.** | Name of reporting person<br>**RA Capital Management, L.P.** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**0.00** | Aggregate amount beneficially owned by each reporting person<br>**0.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**0.0%** | Percent of class represented by amount in Row (11)<br>**0.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IA** | Type of Reporting Person (See Instructions)<br>**IA** | |

---

| **CUSIP No.** | **282559103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Peter Kolchinsky** | Name of reporting person<br>**Peter Kolchinsky** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**X1** | Citizenship or place of organization<br>**X1** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**0.00** | Aggregate amount beneficially owned by each reporting person<br>**0.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**0.0%** | Percent of class represented by amount in Row (11)<br>**0.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**HC** | Type of Reporting Person (See Instructions)<br>**HC** | |

---

| **CUSIP No.** | **282559103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Rajeev Shah** | Name of reporting person<br>**Rajeev Shah** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**X1** | Citizenship or place of organization<br>**X1** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**0.00** | Aggregate amount beneficially owned by each reporting person<br>**0.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**0.0%** | Percent of class represented by amount in Row (11)<br>**0.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**HC** | Type of Reporting Person (See Instructions)<br>**HC** | |

---

| **CUSIP No.** | **282559103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**RA Capital Healthcare Fund, L.P.** | Name of reporting person<br>**RA Capital Healthcare Fund, L.P.** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**WC** | Source of funds (See Instructions)<br>**WC** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**0.00** | Aggregate amount beneficially owned by each reporting person<br>**0.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**0.0%** | Percent of class represented by amount in Row (11)<br>**0.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**PN** | Type of Reporting Person (See Instructions)<br>**PN** | |

---

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Common Stock, par value $0.001 per share

**(b) Name of Issuer:**
89BIO, INC.

**(c) Address of Issuer's Principal Executive Offices:**
655 Montgomery Street, Suite 1500, San Francisco, CA, 94111

Item 1 of the Statement is amended and supplemented as follows:

This Amendment No. 14 (this "Amendment No. 14" or this "13D/A") amends and supplements the Schedule 13D originally filed with the Securities and Exchange Commission (the "SEC") on November 13, 2019, and amended on July 10, 2020, September 21, 2020, June 2, 2021, July 6, 2022, October 21, 2022, March 30, 2023, August 11, 2023, December 13, 2023, March 6, 2024, August 7, 2024, November 18, 2024, February 3, 2025 and March 3, 2025 (as amended, the "Statement"), filed by RA Capital Management, L.P., Dr. Kolchinsky, Mr. Shah, and RA Capital Healthcare Fund, L.P. with respect to the common stock, par value $0.001 per share (the "Common Stock"), of 89bio, Inc., a Delaware corporation (the "Issuer"). Unless otherwise defined herein, capitalized terms used in this Amendment No. 14 shall have the meanings ascribed to them in the Statement. Unless amended or supplemented below, the information in the Statement remains unchanged.

**Item 5. Interest in Securities of the Issuer**

**(a)**
The information set forth in rows 11 and 13 of the cover pages to this Schedule 13D/A is incorporated by reference.

**(b)**
The information set forth in rows 7 through 10 of the cover pages to this Schedule 13D/A and Item 2 above is incorporated by reference.

**(c)**
None of the Reporting Persons have effected any transactions with respect to the securities of the Issuer since the most recent amendment to this Schedule 13D/A, except that on October 30, 2025, the Reporting Persons tendered all of their shares of Common Stock of the Issuer, consisting of 19,554,319 shares of Common Stock held directly by the Fund and 335,364 shares of Common Stock held directly by the Nexus Fund, pursuant to the terms of an Agreement and Plan of Merger, dated as of September 17, 2025 (the "Merger Agreement"), by and among the Issuer, Roche Holdings, Inc. ("Parent") and Bluefin Merger Subsidiary, Inc., a wholly owned subsidiary of Parent ("Merger Sub"), at an offer price per share of (i) $14.50 per share in cash, without interest (the "Closing Amount") less any required withholding taxes, plus (ii) one non-tradeable contingent value right (each, a "CVR") representing the right to receive certain contingent payments of up to an aggregate amount of $6.00 per share, in cash, without interest less any required withholding taxes, upon the achievement of specified milestones on or prior to the applicable milestone outside dates, subject to and in accordance with the terms of the Contingent Value Rights Agreement (the "CVR Agreement"). After completion of the tender offer, Purchaser merged with and into the Issuer (the "Merger"), effective as of October 30, 2025 (the "Effective Time"), with the Issuer continuing as the surviving entity and a wholly owned subsidiary of Parent.

As of immediately prior to and conditioned upon the occurrence of the Effective Time, and without any action on the part of any holder thereof, pursuant to the Merger Agreement each then-outstanding company-issued warrant that had an exercise price per share that was less than the Closing Amount (each, an "In the Money Warrant"), including 4,331,081 pre-funded warrants ("PFWs") held by the Fund, through which the Fund had the right to acquire 4,331,081 shares of Common Stock, was automatically deemed to be exercised into the number of shares subject to such In the Money Warrant and converted automatically into the right to receive: (A) an amount in cash, without interest and subject to deduction for required withholding taxes, equal to the product of (x) the excess of the Closing Amount over the exercise price of such In the Money Warrant and (y) the number of shares subject to such In the Money Warrant, plus (B) one CVR with respect to each share subject to such In the Money Warrant.

As of immediately prior to and conditioned upon the occurrence of the effective time of the Merger, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, an "Option"), including a total of 180,450 stock options (right to buy) held by Derek DiRocco for the benefit of RA Capital, became fully vested and exercisable, and to the extent not exercised prior to the effective time of the Merger, was cancelled and converted into the right to receive (i) an amount in cash (without interest and subject to deduction for any required withholding taxes) equal to the product of (A) an amount equal to the excess of the Closing Amount over the exercise price per Share with respect to such Option and (B) the number of Shares subject to such Option plus (ii) one CVR with respect to each Share subject to such Option (the "Option Consideration"); provided, however, that if the exercise price per Share of any Option was equal to or greater than the Closing Amount, but less than $20.50 (any such option, an "Out of the Money Option"), such Out of the Money Option was not entitled to any payment of the Closing Amount in respect thereof and each Out of the Money Option was converted into the right to receive the CVR included in the Option Consideration with respect to each Share underlying such Out of the Money Option and became entitled to receive, at each time a milestone payment becomes due and payable under the terms of the CVR Agreement, an amount in cash equal to the product of (i) the number of Shares subject to such Out of the Money Option, and (ii) the amount, if any, by which (A) the Closing Amount plus the applicable milestone payment plus any other milestone payment that previously became due and payable under the terms of the CVR Agreement exceeds (B) the exercise price per Share with respect to such Out of the Money Option plus the amounts, if any, paid to such Option holder with respect to such CVR in respect of any milestone payments that previously became due and payable under the terms of the CVR Agreement; provided further, that any Option with an exercise price that was equal to or greater than $20.50, was cancelled immediately prior to the effective time of the Merger without the receipt of any payment of the Closing Amount or CVR in respect thereof.

### 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.

**Reporting Person:** RA Capital Management, L.P.

**Signature:** /s/ Peter Kolchinsky

**Name/Title:** By Peter Kolchinsky, Authorized Signatory

**Date:** 11/03/2025

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.

**Reporting Person:** Peter Kolchinsky

**Signature:** /s/ Peter Kolchinsky

**Name/Title:** Peter Kolchinsky

**Date:** 11/03/2025

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.

**Reporting Person:** Rajeev Shah

**Signature:** /s/ Rajeev Shah

**Name/Title:** Rajeev Shah

**Date:** 11/03/2025

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.

**Reporting Person:** RA Capital Healthcare Fund, L.P.

**Signature:** /s/ Peter Kolchinsky

**Name/Title:** By RA Capital Healthcare Fund GP, LLC, its General Partner, By Peter Kolchinsky, Manager

**Date:** 11/03/2025