Zanidatamab With or Without Tislelizumab Yields Clinically Meaningful Survival Benefit in HER2-Positive Advanced Gastroesophageal Adenocarcinoma

In the phase 3 HERIZON-GEA-01 trial, first-line combination zanidatamab and chemotherapy both with and without tislelizumab improved clinical outcomes versus trastuzumab plus chemotherapy in patients with HER2-positive, locally advanced, unresectable, or metastatic gastroesophageal adenocarcinoma (LBA285). The median PFS was 12.4 months with zanidatamab and chemotherapy, 12.4 months with zanidatamab plus tislelizumab and chemotherapy, and 8.1 months with trastuzumab and chemotherapy.