HERIZON-GEA-01 Phase 3: Zanidatamab Plus Tislelizumab and Chemotherapy Lifts Median OS to 27.0 Months in First-Line HER2-Positive Advanced Gastric Cancer

In the HERIZON-GEA-01 study, the zanidatamab plus tislelizumab plus chemotherapy arm achieved a median overall survival of 27.0 months in HER2-positive advanced gastroesophageal adenocarcinoma, with HR=0.65. The global multicenter phase 3 trial reported this second interim OS analysis after a median follow-up of 35.3 months; median OS was 19.6 months in the control arm and 22.9 months in the zanidatamab plus chemotherapy arm, HR=0.76, P=0.0088.