# EDGAR Filing Document

**Accession Number:** 0001884931
**File Stem:** 0000921895-26-001101
**Filing Date:** 2026-4
**Character Count:** 20893
**Document Hash:** aa196bddbe3eae0a18c4b4580df23a83
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000921895-26-001101.hdr.sgml**: 20260428

**ACCESSION NUMBER**: 0000921895-26-001101

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

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20260428

**DATE AS OF CHANGE**: 20260428

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Arbutus Biopharma Corp
- **CENTRAL INDEX KEY:** 0001447028
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 980597776
- **STATE OF INCORPORATION:** A1
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-85963
- **FILM NUMBER:** 26909603

**BUSINESS ADDRESS:**
- **STREET 1:** 701 VETERANS CIRCLE
- **CITY:** WARMINSTER
- **STATE:** PA
- **ZIP:** 18974
- **BUSINESS PHONE:** 604-419-3200

**MAIL ADDRESS:**
- **STREET 1:** 701 VETERANS CIRCLE
- **CITY:** WARMINSTER
- **STATE:** PA
- **ZIP:** 18974

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** TEKMIRA PHARMACEUTICALS Corp
- **DATE OF NAME CHANGE:** 20110607

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** TEKMIRA PHARMACEUTICALS CORP
- **DATE OF NAME CHANGE:** 20081003
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Whitefort Capital Management, LP
- **CENTRAL INDEX KEY:** 0001884931

**ORGANIZATION NAME:**
- **EIN:** 820808818
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

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

**BUSINESS ADDRESS:**
- **STREET 1:** 12 E. 49TH STREET
- **STREET 2:** 40TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10017
- **BUSINESS PHONE:** 2122594370

**MAIL ADDRESS:**
- **STREET 1:** 12 E. 49TH STREET
- **STREET 2:** 40TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10017

## Ex-1

Exhibit 1

**<u>Transactions in the Securities of the Issuer Since the Filing of Amendment No. 3 to the Schedule 13D</u>**

---

| | | | |
|:---|:---|:---|:---|
| &nbsp;&nbsp;<u>Nature of the Transaction</u> | &nbsp;&nbsp; Amount of Securities<br> <u>Purchased/(Sold)</u> | &nbsp;&nbsp;<u>Price ($)</u> | &nbsp;&nbsp; Date of<br> <u>Purchase/Sale</u> |

---

**<u>WHITEFORT CAPITAL MASTER FUND, LP</u>**

---

| | | | |
|:---|:---|:---|:---|
| &nbsp;&nbsp;Purchase of Common Stock | &nbsp;&nbsp;1500000 | &nbsp;&nbsp;$4.1500 | &nbsp;&nbsp;04/23/2026 |
| &nbsp;&nbsp;Purchase of Common Stock | &nbsp;&nbsp;2000000 | &nbsp;&nbsp;$4.0500 | &nbsp;&nbsp;04/24/2026 |
| &nbsp;&nbsp;Sale of Common Stock | &nbsp;&nbsp;(3500000) | &nbsp;&nbsp;$4.2800 | &nbsp;&nbsp;04/27/2026 |
| &nbsp;&nbsp;Purchase of Cash-Settled Total Return Swap | &nbsp;&nbsp;3500000 | &nbsp;&nbsp;$4.2800 | &nbsp;&nbsp;04/27/2026 |

---

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

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 4)**

**Arbutus Biopharma Corp**

*(Name of Issuer)*

**Common Shares, without par value**

*(Title of Class of Securities)*

**—**

*(CUSIP Number)*

**DAVID SALANIC**<br>WHITEFORT CAPITAL MANAGEMENT, LP<br>12 East 49th Street, 40th Floor<br>New York NY 10017<br>212-259-4370

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

**04/24/2026**

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

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Whitefort Capital Master Fund, LP** | Name of reporting person<br>**Whitefort Capital Master Fund, LP** | |
| 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>**CAYMAN ISLANDS** | Citizenship or place of organization<br>**CAYMAN ISLANDS** | |
| 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>**15794261.00** |
| 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>**15794261.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | |
| 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>**8.0%** | Percent of class represented by amount in Row (11)<br>**8.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**PN** | Type of Reporting Person (See Instructions)<br>**PN** | |

---

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Whitefort Capital GP, LLC** | Name of reporting person<br>**Whitefort Capital GP, 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>**15794261.00** |
| 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>**15794261.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | |
| 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>**8.0%** | Percent of class represented by amount in Row (11)<br>**8.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Whitefort Capital Management, LP** | Name of reporting person<br>**Whitefort Capital Management, LP** | |
| 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>**15794261.00** |
| 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>**15794261.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | |
| 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>**8.0%** | Percent of class represented by amount in Row (11)<br>**8.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IA** | Type of Reporting Person (See Instructions)<br>**IA** | |

---

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Whitefort Capital Management GP, LLC** | Name of reporting person<br>**Whitefort Capital Management GP, 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>**15794261.00** |
| 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>**15794261.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | |
| 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>**8.0%** | Percent of class represented by amount in Row (11)<br>**8.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**David Salanic** | Name of reporting person<br>**David Salanic** | |
| 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>**I0** | Citizenship or place of organization<br>**I0** | |
| 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>**15794261.00** |
| 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>**15794261.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | |
| 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>**8.0%** | Percent of class represented by amount in Row (11)<br>**8.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Joseph Kaplan** | Name of reporting person<br>**Joseph Kaplan** | |
| 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>**15794261.00** |
| 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>**15794261.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | Aggregate amount beneficially owned by each reporting person<br>**15794261.00** | |
| 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>**8.0%** | Percent of class represented by amount in Row (11)<br>**8.0%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Common Shares, without par value

**(b) Name of Issuer:**
Arbutus Biopharma Corp

**(c) Address of Issuer's Principal Executive Offices:**
701 VETERANS CIRCLE, WARMINSTER, PA, 18974

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

**(a)**
Item 5(a) is hereby amended and restated to read as follows:

The aggregate percentage of Shares reported owned by each person named herein is based upon 196,939,679 Shares outstanding as of March 30, 2026, which is the total number of Shares outstanding as reported in the Issuer's definitive proxy statement on Schedule 14A filed with the Securities and Exchange Commission on April 14, 2026.

As of the date hereof, Whitefort Master Fund beneficially owns 15,794,261 Shares, constituting approximately 8.0% of the Shares outstanding.

Whitefort Master GP, as the general partner of Whitefort Master Fund, may be deemed to beneficially own the 15,794,261 Shares owned by Whitefort Master Fund, constituting approximately 8.0% of the Shares outstanding.

Whitefort Management, as the investment manager of Whitefort Master Fund, may be deemed to beneficially own the 15,794,261 Shares owned by Whitefort Master Fund, constituting approximately 8.0% of the Shares outstanding.

Whitefort GP, as the general partner of Whitefort Management, may be deemed to beneficially own the 15,794,261 Shares owned by Whitefort Master Fund, constituting approximately 8.0% of the Shares outstanding.

Each of Messrs. Salanic and Kaplan, as a Co-Managing Partner of Whitefort Management and a Co-Managing Member of each of Whitefort Master GP and Whitefort GP, may be deemed to beneficially own the 15,794,261 Shares owned by Whitefort Master Fund, constituting approximately 8.0% of the Shares outstanding.

The filing of this Schedule 13D shall not be deemed an admission that the Reporting Persons are, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, the beneficial owners of any securities of the Issuer he or it does not directly own. Each of the Reporting Persons specifically disclaims beneficial ownership of the securities reported herein that he or it does not directly own.

**(b)**
—

**(c)**
Item 5(c) is hereby amended and restated to read as follows:

The transactions in securities of the Issuer by the Reporting Persons since the filing of Amendment No. 3 by the Reporting Persons are set forth in Exhibit 1 and are incorporated herein by reference. Except for the swap transaction on April 27, 2026, the counterparty of which was Nomura Global Financial Products Inc. ("Nomura"), and the sale of Shares on the same date, all of such transactions were effected in the open market.

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

Item 6 is hereby amended to add the following:

Whitefort Master Fund has entered into a certain cash-settled total return swap agreement with Nomura as the counterparty (the "Swap Agreement"). Whitefort Master Fund's swap with Nomura constitutes economic exposure to an aggregate of 3,500,000 notional Shares, representing approximately 1.8% of the outstanding Shares, and has a maturity date of October 29, 2029 and a reference price of $4.2800. The Swap Agreement provides Whitefort Master Fund with economic results that are comparable to the economic results of ownership but does not provide it with the power to vote or direct the voting or dispose of or direct the disposition of the Shares that are the subject of the Swap Agreement (such shares, the "Subject Shares"). Taking into account the Subject Shares, Whitefort Master Fund has economic exposure to an aggregate of 19,294,261 Shares, representing approximately 9.8% of the outstanding Shares. The Reporting Persons disclaim beneficial ownership of the Subject Shares.

### 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:** Whitefort Capital Master Fund, LP

**Signature:** /s/ David Salanic

**Name/Title:** David Salanic, Co-Managing Member of Whitefort Capital GP, LLC, its General Partner

**Date:** 04/28/2026

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:** Whitefort Capital GP, LLC

**Signature:** /s/ David Salanic

**Name/Title:** David Salanic, Co-Managing Member

**Date:** 04/28/2026

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:** Whitefort Capital Management, LP

**Signature:** /s/ David Salanic

**Name/Title:** David Salanic, Co-Managing Partner

**Date:** 04/28/2026

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:** Whitefort Capital Management GP, LLC

**Signature:** /s/ David Salanic

**Name/Title:** David Salanic, Co-Managing Member

**Date:** 04/28/2026

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:** David Salanic

**Signature:** /s/ David Salanic

**Name/Title:** David Salanic

**Date:** 04/28/2026

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:** Joseph Kaplan

**Signature:** /s/ Joseph Kaplan

**Name/Title:** Joseph Kaplan

**Date:** 04/28/2026