Ziihera® (zanidatamab-hrii) Combinations Achieve Unprecedented Results in First-Line HER2+ Locally Advanced or Metastatic GEA including more than Two Years Median Overall Survival Benefit

VANCOUVER, British Columbia, Jan. 06, 2026 (GLOBE NEWSWIRE) -- 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 positive efficacy and safety results from the Phase 3 HERIZON-GEA-01 trial evaluating Ziihera® (zanidatamab-hrii) in combination with chemotherapy, with or without the PD-1 inhibitor Tevimbra® (tislelizumab), as first-line treatment for adults with HER2-positive (HER2+) locally advanced or metastatic gastroesophageal adenocarcinoma (GEA), including cancers of the stomach, gastroesophageal junction and esophagus.