# EDGAR Filing Document

**Accession Number:** 0001937653
**File Stem:** 0000935836-25-000439
**Filing Date:** 2025-6
**Character Count:** 23108
**Document Hash:** e0aa0d354efcf532fc4cb4d2ee1aee04
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000935836-25-000439.hdr.sgml**: 20250627

**ACCESSION NUMBER**: 0000935836-25-000439

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20250627

**DATE AS OF CHANGE**: 20250627

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Zymeworks Inc.
- **CENTRAL INDEX KEY:** 0001937653
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 883099146
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-93790
- **FILM NUMBER:** 251088291

**BUSINESS ADDRESS:**
- **STREET 1:** 108 PATRIOT DRIVE, SUITE A
- **CITY:** MIDDLETOWN
- **STATE:** DE
- **ZIP:** 19709
- **BUSINESS PHONE:** 302-274-8744

**MAIL ADDRESS:**
- **STREET 1:** 108 PATRIOT DRIVE, SUITE A
- **CITY:** MIDDLETOWN
- **STATE:** DE
- **ZIP:** 19709

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Zymeworks Delaware Inc.
- **DATE OF NAME CHANGE:** 20220712
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** EcoR1 Capital, LLC
- **CENTRAL INDEX KEY:** 0001587114

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

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

**BUSINESS ADDRESS:**
- **STREET 1:** 357 TEHAMA STREET #3
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94103
- **BUSINESS PHONE:** 415-448-6534

**MAIL ADDRESS:**
- **STREET 1:** 357 TEHAMA STREET #3
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94103

## Exhibit 99.1

EXHIBIT 99.1

AGREEMENT REGARDING JOINT FILING

OF STATEMENT ON SCHEDULE 13D OR 13G

The undersigned agree to file jointly with the Securities and Exchange Commission (the "SEC") any and all statements on Schedule 13D or Schedule 13G or Forms 3, 4 or 5(and any amendments or supplements thereto) required under section 13(d) and 16(a) of the Securities Exchange Act of 1934, as amended, in connection with purchases by the undersigned of the securities of any issuer. For that purpose, the undersigned hereby constitute and appoint EcoR1 Capital, LLC, a Delaware limited liability company, as their true and lawful agent and attorney-in-fact, with full power and authority for and on behalf of the undersigned to prepare or cause to be prepared, sign, file with the SEC and furnish to any other person all certificates, instruments, agreements and documents necessary to comply with section 13(d) and section 16(a) of the Securities Exchange Act of 1934, as amended, in connection with said purchases, and to do and perform every act necessary and proper to be done incident to the exercise of the foregoing power, as fully as the undersigned might or could do if personally present.

Dated: June 27, 2025

---

| |
|:---|
| &nbsp;&nbsp; **ECOR1 CAPITAL, LLC**<br>By: *<u>/s/ Oleg Nodelmman</u>* <br> Oleg Nodelman<br> Manager<br>|
| &nbsp;&nbsp; **ECOR1 CAPITAL FUND QUALIFIED, L.P.<br>** <br> By: EcoR1 Capital, LLC,<br> General Partner<br>By: *<u>/s/ Oleg Nodelman</u>* <br> Oleg Nodelman<br> Manager<br>|
| &nbsp;&nbsp; <br> *<u>/s/ Oleg Nodelman</u>* <br> Oleg Nodelman |

---

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

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**Zymeworks Inc.**

*(Name of Issuer)*

**Common Stock**

*(Title of Class of Securities)*

**98985Y108**

*(CUSIP Number)*

**Anthony J. Caldwell, Esq.**<br>Shartsis Friese, LLP<br>425 Market Street, 11th Floor<br>San Francisco CA 94105<br>415-421-6500

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

**06/26/2025**

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

| **CUSIP No.** | **98985Y108** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**EcoR1 Capital, LLC** | Name of reporting person<br>**EcoR1 Capital, LLC** | |
| 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>**22970388.00** |
| 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>**22970388.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**22970388.00** | Aggregate amount beneficially owned by each reporting person<br>**22970388.00** | |
| 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>**30.7%** | Percent of class represented by amount in Row (11)<br>**30.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IA** | Type of Reporting Person (See Instructions)<br>**IA** | |

---

**Comment for Reporting Person:** Percentage calculated based on 74,844,505 shares of Common Stock outstanding following the exercise of Pre-Funded Warrants by the reporting persons, as reported in the Form 8-K filed by the Issuer on June 27, 2025.

| **CUSIP No.** | **98985Y108** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Oleg Nodelman** | Name of reporting person<br>**Oleg Nodelman** | |
| 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>**22970388.00** |
| 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>**22970388.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**22970388.00** | Aggregate amount beneficially owned by each reporting person<br>**22970388.00** | |
| 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>**30.7%** | Percent of class represented by amount in Row (11)<br>**30.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** Percentage calculated based on 74,844,505 shares of Common Stock outstanding following the exercise of Pre-Funded Warrants by the reporting persons, as reported in the Form 8-K filed by the Issuer on June 27, 2025.

| **CUSIP No.** | **98985Y108** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**EcoR1 Capital Fund Qualified, L.P.** | Name of reporting person<br>**EcoR1 Capital Fund Qualified, 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>**21582563.00** |
| 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>**21582563.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**21582563.00** | Aggregate amount beneficially owned by each reporting person<br>**21582563.00** | |
| 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>**28.8%** | Percent of class represented by amount in Row (11)<br>**28.8%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**PN** | Type of Reporting Person (See Instructions)<br>**PN** | |

---

**Comment for Reporting Person:** Percentage calculated based on 74,844,505 shares of Common Stock outstanding following the exercise of Pre-Funded Warrants by the reporting persons, as reported in the Form 8-K filed by the Issuer on June 27, 2025.

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Common Stock

**(b) Name of Issuer:**
Zymeworks Inc.

**(c) Address of Issuer's Principal Executive Offices:**
108 PATRIOT DRIVE, SUITE A, MIDDLETOWN, DE, 19709

**Item 4. Purpose of Transaction**

Oleg Nodelman, the manager of EcoR1, and Scott Platshon, one of EcoR1's employees, are members of the Issuer's board of directors.  The reporting persons acquired the Common Stock for investment purposes based on their belief that the Issuer's Common Stock, when purchased, was undervalued and represented an attractive investment opportunity.  The reporting persons will routinely monitor the Issuer regarding a wide variety of factors that affect their investment considerations, including, current and anticipated future trading prices of the Common Stock and other securities, the Issuer's operations, assets, prospects, financial position, and business development, Issuer's management, Issuer-related competitive and strategic matters, general economic, financial market and industry conditions, and other investment considerations. Depending on their evaluation of various factors, the reporting persons may take such actions regarding their holdings of the Issuer's securities as they deem appropriate in light of circumstances existing from time to time. Such actions may include purchasing additional Common Stock in the open market, through privately negotiated transactions with third parties or otherwise,  and selling at any time, in the open market, through privately negotiated transactions with third parties or otherwise, all or part of the Common Stock that they now own or hereafter acquire. The reporting persons also may from time to time enter into or unwind hedging or other derivative transactions with respect to the Common Stock or pledge their interests in the Common Stock to obtain liquidity. In addition, from time to time the reporting persons and their representatives and advisers may communicate with other stockholders, industry participants and other interested parties about the Issuer.

The reporting persons have no present plan or proposal that relates to or would result in any of the actions specified in clauses (a) through (j) of Item 4 of Schedule 13D.  However, the reporting persons may recommend action to the Issuer's management, board of directors and stockholders. Any such actions could involve one or more of the events referred to in clauses (a) through (j) of Item 4 of Schedule 13D, including, potentially, one or more mergers, consolidations, sales or acquisitions of assets, changes in control, issuances, purchases, dispositions or pledges of securities or other changes in capitalization.

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

**(a)**
Aggregate number of shares beneficially owned by the reporting persons:

EcoR1:  22,970,388

Oleg Nodelman:  22,970,388

Qualified Fund:  21,582,563

Aggregate percentage of the class of stock beneficially owned by the reporting persons:

EcoR1:  30.7%

Oleg Nodelman:  30.7%

Qualified Fund:  28.8%

**(b)**
Number of shares as to which each reporting person has:
i) Sole power to vote or to direct the vote:

EcoR1:  0

Oleg Nodelman:  0

Qualified Fund:  0

(ii) Shared power to vote or to direct the vote:

EcoR1:  22,970,388

Oleg Nodelman:  22,970,388

Qualified Fund:  21,582,563

(iii) Sole power to dispose or to direct the disposition of:

EcoR1:  0

Oleg Nodelman:  0

Qualified Fund:  0

(iv) Shared power to dispose or to direct the disposition of:

EcoR1:  22,970,388

Oleg Nodelman:  22,970,388

Qualified Fund:  21,582,563

**(c)**
The reporting persons engaged in the following transactions in the Issuer's Common Stock in the 60 days preceding the date of this Schedule 13D:

On 5/15/2025, the Funds purchased 49,502 shares of the Issuer's Common Stock for a price of $11.4308 per share.  Qualified Fund purchased 46,405 of these shares.

On 5/19/2025, the Funds purchased 5,919 shares of the Issuer's Common Stock for a price of $11.7821 per share.  Qualified Fund purchased 5,550 of these shares.

On 6/26/2025, the Funds exercised Pre-Funded Warrants to purchase 5,086,521 shares of the Issuer's Common Stock for $0.0001 per share.  Qualified Fund exercised warrants to purchase 4,818,462 of these shares.  The reporting persons paid the exercise price on a cashless basis, resulting in the Issuer withholding 41 of the warrant shares (including 38 warrant shares issuable to Qualified Fund) to pay the exercise price and issuing to the reporting persons the remaining 5,086,480 shares.

**Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.**

EcoR1 is the investment adviser to its clients pursuant to investment management agreements or limited partnership agreements providing to EcoR1 the authority, among other things, to invest the funds of such clients in Stock, to vote and dispose of Stock and to file this statement on behalf of such clients. Pursuant to such limited partnership agreements, EcoR1 is entitled to allocations based on assets under management and realized and unrealized gains.  Pursuant to such investment management agreements, EcoR1 is entitled to fees based on assets under management and realized and unrealized gains.

Securities Purchase Agreement

On December 23, 2023, the reporting persons entered into a securities purchase agreement (the "Securities Purchase Agreement") for a private placement with the Issuer. Pursuant to the Securities Purchase Agreement, the reporting persons purchased pre-funded warrants (the "Pre-Funded Warrants") to purchase 5,086,521 shares of Common Stock of the Issuer (the "Warrant Shares").  In addition, the Issuer agreed that EcoR1 had the right to nominate one of its partners as a member of the board of directors of the Issuer, subject to specified conditions. EcoR1 exercised this right to appoint Scott Platshon to the Issuer's board of directors.

Pre-Funded Warrants

The Pre-Funded Warrants were exercisable at an exercise price equal to $0.0001 per share, subject to adjustments as provided under the terms of the Pre-Funded Warrants.  The Pre-Funded Warrants were exercisable at any time.  On June 26, 2025, the Funds and the Issuer entered into an Amendment No. 1 to the Pre-Funded Warrants to remove the limitation that the Pre-Funded Warrants cannot be exercised if, after giving effect or immediately prior to such exercise, the reporting persons, together with their affiliates and any other persons whose beneficial ownership of shares of Common Stock would be aggregated with the reporting persons for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), would beneficially own more than 19.99% of the total number of issued and outstanding shares of Common Stock or voting power of the Issuer following such exercise.  The Funds exercised the Pre-Funded W arrants in full on June 26, 2025.

Registration Rights Agreement

The reporting persons also entered into a registration rights agreement (the "Registration Rights Agreement") with the Issuer on December 23, 2023, requiring the Issuer to register the resale of the Warrant Shares (the "Registrable Securities"). Under the Registration Rights Agreement, the Issuer agreed to file a registration statement covering the resale by the reporting persons of their Registrable Securities upon the earlier of March 15, 2024 and the first business day following the date that the Issuer files it Annual Report on Form 10-K for the fiscal year ended December 31, 2023 (the "Filing Deadline").

The Issuer agreed to use commercially reasonable efforts to cause such registration statement or final prospectus, as applicable, to be declared effective as soon as practicable, but no later than the later of April 29, 2024 and the 123rd calendar day following the closing date (the "Effectiveness Deadline"), and to keep such registration statement effective for a period that will terminate upon the earliest of (i) the date that all Registrable Securities covered by such registration statement or final prospectus, as applicable, have been sold, (ii) the date that all Registrable Securities covered by such registration statement or final prospectus, as applicable, may be sold without the requirement for the Issuer to be in compliance with the current public information required under Rule 144 as to such Registrable Securities and without volume or manner-of-sale restrictions and (iii) two (2) years after the date of the Securities Purchase Agreement. The Issuer agreed to be responsible for all reasonable expenses in connection with the filing of any registration statement or final prospectus, as applicable. For the avoidance of doubt, the fees and expenses of the reporting persons' counsel shall be the responsibility of the reporting persons, and not the Issuer.
In the event (i) the registration statement or final prospectus, as applicable, covering the Registrable Securities has not been filed with the Securities and Exchange Commission (the "SEC") on or prior to the Filing Deadline, (ii) the registration statement or final prospectus, as applicable, covering the Registrable Securities is not declared effective by the SEC prior to the earlier of (a) ten (10) business days after the date on which the Issuer is notified by the SEC that the registration statement or final prospectus, as applicable, will not be reviewed by the SEC or is not subject to further comment by the SEC and (b) the Effectiveness Deadline, or (iii) after the registration statement or final prospectus, as applicable, has been declared effective by the SEC, sales cannot be made pursuant to the registration statement or final prospectus, as applicable, for any reason, subject to certain limited exceptions, then the Issuer has agreed to make pro rata payments to each reporting person as liquidated damages and not as a penalty, in an amount equal to one percent (1%) of the aggregate purchase price paid by such Issuer pursuant to the Securities Purchase Agreement for any shares of Common Stock held by such Issuer pursuant to the exercise of Pre-Funded Warrants but not for any unissued shares of Common Stock issuable upon exercise of the Pre-Funded Warrants for each 30-day period or pro rata for any portion thereof (a) following the Filing Deadline for which no registration statement or final prospectus, as applicable, is filed with respect to the Registrable Securities or (b) during which such registration statement or final prospectus, as applicable, is unavailable, as applicable. Payment of such liquidated damages shall be the reporting persons' exclusive remedy for such events. In addition, (i) the aggregate amount of liquidated damages payable to a reporting person shall not exceed, in the aggregate, six percent (6%) of the aggregate purchase price paid by such reporting person and (ii) the Issuer shall not be liable in any thirty (30) day period for liquidated damages in excess of one percent (1%) of the aggregate purchase price paid by the  reporting person.

The Issuer has granted the reporting persons customary indemnification rights in connection with the registration statement. The reporting persons have also granted the Issuer customary indemnification rights in connection with the registration statement.

The foregoing description of the material terms of the Securities Purchase Agreement, the Registration Rights Agreement, the Pre-Funded Warrant and Amendment No. 1 to the Pre-Funded Warrants is qualified in its entirety by reference to those documents, each of which is referenced in Exhibits 99.2, 99.3, 99.4 and 99.5 hereto, respectively, and is incorporated by reference herein.

### 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:** EcoR1 Capital, LLC

**Signature:** /s/ Oleg Nodelman

**Name/Title:** Manager

**Date:** 06/27/2025

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:** Oleg Nodelman

**Signature:** /s/ Oleg Nodelman

**Name/Title:** Reporting person

**Date:** 06/27/2025

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:** EcoR1 Capital Fund Qualified, L.P.

**Signature:** /s/ Oleg Nodelman

**Name/Title:** Manager of the General Partner, EcoR1 Capital, LLC

**Date:** 06/27/2025