Arbutus Biopharma Corp

Trading Plans

During the three months ended March 31, 2025, none of our directors or officers adopted, modified orterminated a “Rule 10b5-1 trading arrangement” or a “non-Rule 10b5-1 trading arrangement” as such terms are defined under Item 408 of Regulation S-K, except as follows:

•On March 28, 2025, Tuan Nguyen, our Chief Financial Officer, entered into a sell-to-cover instruction letter (the Sell-to-Cover Instruction Letter) which constitutes a “Rule 10b5-1 trading arrangement,” intended to satisfy the affirmative defense of Rule 10b5-1(c) of the Securities Exchange Act of 1934, as amended. The Sell-to-Cover Instruction Letter, which applies to grants of restricted stock units (RSUs) whether vesting is based on the passage of time and/or the achievement of performance criteria, provides for the automatic sale of common shares as soon as practicable on or after each settlement date of a covered RSU in an amount sufficient to satisfy the applicable tax withholding obligation, with the proceeds of the sale delivered to us in satisfaction of the applicable tax withholding obligation. The number of common shares subject to covered RSUs that will be sold to satisfy the applicable tax withholding obligations upon vesting is unknown as the number will vary based on the extent to which vesting conditions are satisfied, the market price of the common shares at the time of settlement and the potential future grants of RSUs subject to the Sell-to-Cover Instruction Letter. The expiration date of the Sell-to-Cover Instruction Letter is the date on which the tax withholding obligation arising from the vesting of all covered RSUs and the related issuance of common shares has been satisfied. Mr Nguyen does not currently hold any RSUs, but he may become eligible to receive grants of RSUs in the future.