carboplatin + gemcitabine + metformin

This is a combination regimen consisting of three drugs—carboplatin, gemcitabine, and metformin. Carboplatin is a platinum-based chemotherapeutic agent that causes DNA crosslinking and apoptosis in rapidly dividing cells. Gemcitabine is a nucleoside analog that inhibits DNA synthesis, leading to cell death in proliferating cancer cells. Metformin is an oral antihyperglycemic agent commonly used for type 2 diabetes; it also exhibits antitumor activity through inhibition of mitochondrial complex I and activation of AMP-activated protein kinase (AMPK), resulting in reduced cellular proliferation and metabolic stress on tumor cells. Preclinical studies suggest that combining these agents may have synergistic or additive anticancer effects by targeting different pathways involved in tumor growth and survival. For example, metformin has been shown to sensitize cancer cells to carboplatin by reversing resistance mechanisms[4], while the combination with gemcitabine can enhance apoptosis or inhibit proliferation depending on the context[1][3]. The dual chemotherapy backbone of carboplatin plus gemcitabine (sometimes called "GemCarbo") is already established as first-line therapy for several cancers such as bladder cancer[5][6]. The addition of metformin represents an investigational approach aimed at improving efficacy via metabolic modulation.