surufatinib + toripalimab + gemcitabine + oxaliplatin

This is a combination regimen consisting of four agents: - **Surufatinib** is an oral small molecule tyrosine kinase inhibitor that targets vascular endothelial growth factor receptors (VEGFR1, VEGFR2, VEGFR3), fibroblast growth factor receptor 1 (FGFR1), and colony-stimulating factor 1 receptor (CSF-1R). It inhibits angiogenesis and modulates the tumor microenvironment by affecting tumor-associated macrophages[4][5][7]. - **Toripalimab** is a humanized IgG4 monoclonal antibody targeting programmed cell death protein 1 (PD-1), functioning as an immune checkpoint inhibitor to enhance T-cell mediated antitumor immunity[4][5][7]. - **Gemcitabine** is a nucleoside analog used as chemotherapy; it inhibits DNA synthesis by incorporating into DNA strands during replication, leading to apoptosis in rapidly dividing cells[6][8]. - **Oxaliplatin** is a platinum-based chemotherapeutic agent that forms crosslinks in DNA, inhibiting replication and transcription, resulting in cell death[6][8]. The combination of surufatinib and toripalimab has shown promising antitumor activity with manageable safety profiles across several advanced solid tumors including non-small-cell lung cancer, neuroendocrine carcinoma, gastric/gastroesophageal adenocarcinoma, intrahepatic cholangiocarcinoma, and others. Gemcitabine plus oxaliplatin regimens are established chemotherapies for various cancers. The quadruple combination aims to leverage antiangiogenic effects (surufatinib), immune checkpoint blockade (toripalimab), and cytotoxic chemotherapy (gemcitabine/oxaliplatin) for synergistic efficacy.