pembrolizumab + cisplatin + capecitabine

This drug is a combination of **pembrolizumab**, a monoclonal antibody immune checkpoint inhibitor targeting PD-1, and two cytotoxic chemotherapeutic agents: **cisplatin**, a platinum-based DNA-damaging agent, and **capecitabine**, an oral prodrug of 5-fluorouracil that interferes with DNA synthesis. Pembrolizumab works by blocking the PD-1 pathway, thereby enhancing T-cell mediated antitumor immune responses. Cisplatin induces DNA crosslinks, leading to apoptosis of rapidly dividing cells. Capecitabine is enzymatically converted to 5-fluorouracil (5-FU) in tumor tissue and inhibits thymidylate synthase, disrupting DNA production and repair. This triple combination is being studied primarily as a first-line treatment for advanced or metastatic cancers such as gastric or gastroesophageal junction (EGJ) adenocarcinoma and is also of interest for other solid tumors. Clinical trials in these indications often allow either 5-FU or capecitabine as the fluoropyrimidine component, based on investigator choice or patient condition[1][6][10].