Zymeworks Inc. (NASDAQ: ZYME) has announced positive topline results from the phase 3 Herizon-GEA-01 trial, evaluating ZW25, also known as Zanidatamab-HR11, in combination with chemotherapy. These results support ZW25's potential to become the her2-targeted agent of choice in first-line gastroesophageal adenocarcinoma (GEA).
Key findings from the Herizon-GEA-01 trial include: ZW25 plus chemotherapy and ZW25 plus tevimbra and chemotherapy demonstrated highly statistically significant and clinically meaningful improvements in progression-free survival (PFS) compared to the control arm, trastuzumab plus chemotherapy. ZW25 plus tevimbra and chemotherapy also showed clinically meaningful and statistically significant improvements in overall survival (OS), and ZW25 plus chemotherapy demonstrated a clinically meaningful effect with a strong trend toward statistical significance for OS. * Both ZW25 combinations demonstrated improvements in key secondary endpoints of objective response rate (ORR) and duration of response (DOR) compared to the control arm.
The safety profile of ZW25 in combination with chemotherapy, with or without tevimbra, was generally consistent with the known safety profile of each agent with no new safety signals observed in the two investigational combination arms.
Jazz Pharmaceuticals intends to submit a supplemental biologics license application in the first half of 2026 to support ZW25 as a first-line treatment for patients with her2+ locally advanced or metastatic GEA for use as part of a standard chemotherapy regimen with or without tevimbra.
Kenneth Galbraith, Chair and Chief Executive Officer of Zymeworks, expressed optimism about the potential of ZW25 to transform the standard of care in her2+ indications.
Zanidatamab, also known as ZW25, has received accelerated approval from the U.S. FDA, conditional approval from the NMPA in China, and conditional marketing authorization from the European Commission for the treatment of adults with previously treated, unresectable, or metastatic her2-positive biliary tract cancer. It is also being evaluated in multiple global clinical trials as a potential best-in-class treatment for patients with multiple her2-expressing cancers.
These positive results mark a significant advancement in the treatment of her2+ gastroesophageal adenocarcinoma and could potentially offer new hope for patients with limited treatment options and poor outcomes. The market has reacted to these announcements by moving the company's shares 0.11% to a price of $18.52. For the full picture, make sure to review Zymeworks's 8-K report.
