An Investigational Study of Immunotherapy Combinations With Chemotherapy in Patients With Gastric or Gastroesophageal Junction (GEJ) Cancers

Inclusion Criteria

• Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1
• Histologically- or cytologically-confirmed diagnosis of unresectable and either locally advanced, or metastatic gastric cancer or GEJ adenocarcinoma
• No prior treatment with systemic treatment (including HER 2 inhibitors) given as primary therapy for unresectable and either locally advanced, or metastatic GC or GEJ adenocarcinoma
• Tumor tissue must be provided for biomarker analyses

Exclusion Criteria

• Participants with HER2 positive status
• Participants with known untreated central nervous system (CNS) metastases
• Uncontrolled or significant cardiovascular disease Other protocol defined inclusion/exclusion criteria could apply