envafolimab + gemcitabine + cisplatin + simvastatin

This combination therapy comprises **envafolimab** (a subcutaneously administered monoclonal antibody targeting PD-L1), **gemcitabine** (a nucleoside analog DNA synthesis inhibitor), **cisplatin** (a platinum-based DNA crosslinking agent), and **simvastatin** (a statin that inhibits HMG-CoA reductase, primarily used for cholesterol lowering but explored for anticancer synergy). - **Envafolimab** acts as an immune checkpoint inhibitor by blocking PD-L1, thus enhancing T-cell–mediated immune responses against tumors. - **Gemcitabine** and **cisplatin** function as cytotoxic chemotherapies, disrupting DNA synthesis and repair. - **Simvastatin** is being investigated for its potential adjunctive antitumor effects. This four-drug regimen is under clinical investigation as a first-line treatment for advanced biliary tract cancers, aiming to improve antitumor efficacy through combined immunotherapy, chemotherapy, and possible statin-mediated effects[4][5][6].