Merck Sharp & Dohme LLC
This is a phase 1/2, multicenter, open-label umbrella platform study that will evaluate the safety and tolerability of investigational agents with pembrolizumab and fluoropyrimidine chemotherapy for the first-line (1L) treatment of participants with locally advanced unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric, gastroesophageal junction, or esophageal adenocarcinoma. This substudy will have two phases: a safety lead-in phase and an efficacy phase. The safety lead-in phase will be used to evaluate the safety and tolerability, and to establish a recommended Phase 2 dose (RP2D) for investigational agents in combination with chemotherapy and immunotherapy. There is no formal hypothesis in this study.
The master protocol is MK-3475-U06.
Inclusion Criteria: The main inclusion criteria include but are not limited to the following: * Has histologically and/or cytologically confirmed diagnosis of previously untreated locally advanced unresectable or metastatic first-line (1L) gastroesophageal adenocarcinoma * Is not expected to require tumor resection during the treatment course * Tumor tissue must be confirmed as negative for human epidermal growth factor receptor 2 (HER2) expression as classified by American Society of Clinical Oncology/College of American Pathologists (ASCO-CAP) guidelines * Core/excisional biopsy of a tumor…
Administered via intravenous (IV) infusion.
Administered via IV infusion.
Administered via oral tablet.
Administered via IV infusion.
Administered via IV infusion.
Administered via IV infusion
Administered via IV infusion
Administered via IV infusion