Zymeworks Reports Incentive Grant Under Nasdaq Stock Market Rule 5635(c) Page 1

VANCOUVER, British Columbia, Sept. 3, 2024 (GLOBE NEWSWIRE) — Zymeworks Inc. (Nasdaq: ZYME), a clinical-stage biotechnology company developing a diverse pipeline of novel, multifunctional biotherapeutics to improve the standard of care for difficult-to-treat diseases, today announced, as required by Nasdaq Stock Market Rule 5635(c) (the “Nasdaq Rule”), an equity incentive award to Ms. Leone Patterson, Executive Vice President and Chief Business and Financial Officer of Zymeworks.

In accordance with the Nasdaq Rule, Zymeworks has approved the grant of the following stock award to Ms. Patterson as a material incentive for Ms. Patterson to join Zymeworks: effective September 1, 2024, the date her employment with Zymeworks began (the “Commencement Date”), a stock option to purchase 360,000 shares of the Company’s common stock (the “Option”). The Option has an exercise price per share of $11.73, which is equal to the closing price of the Company’s common stock on August 30, 2024, and has a maximum term of 10 years.