Zymeworks Inc. (NASDAQ:ZYME), a biotechnology company managing a portfolio of licensed healthcare assets while developing a diverse pipeline of novel, multifunctional biotherapeutics, today announced results from the dose-escalation part of the Phase 1 study for ZW191, a folate receptor alpha (FRα)-targeting antibody-drug conjugate (ADC), at the 2026 American Association for Cancer Research (AACR) Annual Meeting.

The data from Part 1 of the ongoing global Phase 1 study (ZWI-ZW191-101), highlight a compelling combination of anti-tumor activity and manageable safety in patients with advanced, heavily pretreated solid tumors, including ovarian and endometrial cancers.

"We are highly encouraged by the initial clinical data for ZW191, which reinforce the strength of our ADC platform and its ability to generate differentiated therapeutics," said Sabeen Mekan, M.D., Senior Vice President and Chief Medical Officer at Zymeworks. "The breadth and durability of responses, along with activity across varying levels of FRα expression, support further development of ZW191 as a potential best-in-class agent for patients with ovarian and endometrial cancers."

Part 2a, the dose-optimization portion of the study evaluating patients with ovarian cancer at doses of 6.4 mg/kg and 9.6 mg/kg, has completed enrollment, with participants recruited globally across North America, Europe, and Asia-Pacific. The data from Part 2a will determine the recommended dose for any future registration