Phase II Study of Zanidatamab in Combination With Pembrolizumab and Chemotherapy in HER2 and PD-L1 Positive Metastatic Gastroesophageal Adenocarcinoma (GEA) Patients

Zanidatamab 1,200 mg (patients \<70 kg at baseline) or 1,600 mg (patients ≥70 kg at baseline), administered i.v. on day 1 of each 2-week cycle (Q2W)

Pembrolizumab 400 mg, administered i.v. on day 1 of every third cycle (Q6W)

modified FOLFOX with Oxaliplatin 85 mg/m2 i.v. on day 1; Folinic Acid 400 mg/m2 i.v. on day 1; 5-FU 2,400 mg/m2 i.v. continuous infusion over 48 hours (no bolus!) on days 1 and 2 of each 2-week cycle (Q2W)