Study of PF-08634404 With Chemotherapy Compared to Nivolumab Plus Chemotherapy for Advanced or Metastatic Gastric and Esophageal Adenocarcinoma

What this Trial Is About

Researchers are studying a new medicine called PF-08634404 combined with chemotherapy in people 18 years and older who have locally advanced or metastatic gastric, gastroesophageal junction, or esophageal adenocarcinoma. This study aims to understand how well this combination works and how safe it is compared to another approved treatment, nivolumab plus chemotherapy, in those who have not yet received treatment for advanced disease. Participants will receive intravenous PF-08634404 combined with chemotherapy in repeated treatment cycles. The study has two parts the first part focuses on safety and response to the new treatment, and the second part compares the new treatment plus chemotherapy against nivolumab plus chemotherapy. Treatments are given intravenously, and the study lasts approximately four years to monitor effects and outcomes. During the study, participants will be regularly monitored with medical tests to assess tumor response, side effects, survival, and quality of life. Researchers will collect data on tumor shrinkage using RECIST 1.1 criteria, adverse events, laboratory results, and serum levels of the study drug. Follow-up includes assessments up to 90 days after treatment ends. The total participation duration spans about four years, covering both treatment and observation periods.

Symbiotic-GI-16: A Study to Learn About the Study Medicine Called PF-08634404 in Combination With Chemotherapy in Gastroesophageal Cancer