Jazz Pharmaceuticals Phase 3 Trial Shows Survival Benefit for Ziihera in Gastroesophageal Cancer

06:51 AM EDT, 08/31/2026 (MT Newswires) -- Jazz Pharmaceuticals (JAZZ) said Monday its Phase 3 trial treating advanced gastroesophageal cancer showed that Ziihera with chemotherapy improved overall patient survival compared to trastuzumab with chemotherapy. The drug combination met the study's endpoint in a second interim analysis, showing improved survival odds compared to an earlier analysis, the company said. A separate treatment regimen combining Ziihera with Tevimbra and chemotherapy also showed improved survival results over longer follow-up periods, Jazz Pharmaceuticals said. The US Food and Drug Administration approved Ziihera-based treatments on Aug. 25 for certain adults with advanced stomach and esophageal cancers that have a specific HER2 protein marker, Jazz said. Jazz said it has submitted the new data for presentation at a major medical meeting in Q4 and plans to submit the results to global health authorities.