Pembrolizumab/Placebo Plus Trastuzumab Plus Chemotherapy in Human Epidermal Growth Factor Receptor 2 Positive Advanced Gastric or Gastroesophageal Junction Adenocarcinoma
The study will compare the efficacy and safety of pembrolizumab plus trastuzumab in combination with standard of care (SOC) chemotherapy versus trastuzumab in combination with SOC chemotherapy in participants with HER2-positive