Zymeworks Reminds Shareholders to Vote FOR its Redomicile

Zymeworks Inc. (“Zymeworks” or the “Company”) (NYSE: ZYME), a clinical-stage biopharmaceutical company developing multifunctional biotherapeutics, reminds shareholders that the deadline for voting FOR the Company’s plan to become a Delaware corporation (the “Redomicile”) is 9:00 a.m., Pacific Time, on October 5, 2022. If you require assistance voting your proxy, please contact Kingsdale Advisors at 1-855-476-7981 (within North America), or at 1-416-867-2272 (outside North America), or by email at [e-mail].

“We believe that the Redomicile is in the best interest of Zymeworks,” said Kenneth Galbraith, Chair and CEO of Zymeworks. “We believe the Redomicile will provide greater opportunities to enhance long-term value for securityholders, simplify commercialization efforts and monetization opportunities for our product candidates, and provide greater comparability to our peers. We expect that these factors will better position Zymeworks for future growth.”

The upcoming special meeting of Zymeworks securityholders will be held at the Pearl Room, Fairmont Pacific Rim, 1038 Canada Place, Vancouver, BC V6C 0B9 on October 7, 2022 at 9:00 a.m., Pacific Time. Zymeworks urges securityholders to vote before the deadline of 9:00 a.m., Pacific Time, on October 5, 2022.

Advisors

Kingsdale Advisors is acting as strategic securityholder advisor, proxy solicitation agent, information agent and communications advisor to the Company.

Important Information for Investors and Securityholders

This press release is not intended to and does not constitute an offer to sell, buy or exchange or the solicitation of an offer to sell, buy or exchange any securities or the solicitation of any vote or approval in any jurisdiction, nor shall there be any sale, purchase, or exchange of securities or solicitation of any vote or approval in any jurisdiction in contravention of applicable law. In connection with the proposed Redomicile, Zymeworks has caused its subsidiary Zymeworks Delaware Inc., a Delaware corporation (“New Zymeworks”), to file a registration statement on Form S-4, which includes New Zymeworks’ prospectus as well as Zymeworks’ proxy statement (the “Proxy Statement/Prospectus”), with the U.S. Securities and Exchange Commission (the “SEC”) and the appropriate Canadian securities regulatory authorities. Zymeworks has mailed the Proxy Statement/Prospectus to its shareholders and holders of its warrants and outstanding equity awards in connection with the proposed Redomicile. INVESTORS AND SECURITYHOLDERS OF ZYMEWORKS ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER RELEVANT DOCUMENTS FILED OR TO BE FILED WITH THE SEC AND CANADIAN SECURITIES REGULATORY AUTHORITIES CAREFULLY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT ZYMEWORKS, NEW ZYMEWORKS, THE REDOMICILE, AND RELATED MATTERS. Investors and securityholders are able to obtain free copies of the Proxy Statement/Prospectus and other documents filed with the SEC by Zymeworks or New Zymeworks through the website maintained by the SEC at www.sec.gov (“EDGAR”). Investors and securityholders are also able to obtain free copies of the Proxy Statement/Prospectus and other documents filed with Canadian securities regulatory authorities by Zymeworks, through the website maintained by the Canadian Securities Administrators at www.sedar.com (“SEDAR”). In addition, investors and securityholders are able to obtain free copies of the documents filed with the SEC and Canadian securities regulatory authorities on Zymeworks’ website at www.zymeworks.com or by contacting Zymeworks’ corporate secretary.