A Phase II/III Trial to Evaluate the Efficacy and Safety of Surufatinib Combined With Camrelizumab, Nab-paclitaxel, and Gemcitabine in Metastatic Pancreatic Cancer

Inclusion Criteria: 1. Fully understand and voluntarily sign an informed consent form, willing and able to follow the study process; 2. Age range is 18-75 years old (inclusive); 3. Pancreatic cancer confirmed by histology or cytology; 4. Stage IV metastasis Pancreatic cancer patients; 5. Have not received previous systematic first line anti-tumor treatment in the stage of metastatic pancreatic cancer; 6. According to RECIST 1.1, there is at least one measurable lesion; 7. Eastern Cooperative Oncology Group (ECOG) Performance Status score of 0 or 1; 8. Expected survival time ≥ 12 weeks; Exclusion Criteria: 1. Use of systematic non-specific immunomodulatory therapy within 2weeks prior to the first dose； 2. Presence of other malignancies in the past 5 years; 3. Received major surgical surgery within 4 weeks before the first dose; 4. Received palliative radiotherapy within 1 week before the first dose; received radical radiotherapy within 4 weeks before the first dose; 5. Any known allergy to surufatinib or its components, camrelizumab, nab-paclitaxel, or gemcitabine; 6. Received strong-inducers or strong-inhibitors of cytochrome P450 (CYP) 3A within 2 weeks or 5 half-lives (whichever is longer) before the first dose; 7. Use of immunosuppressive drugs within 4 weeks before first dose; 8. Known history of clinically significant liver disease, including active viral hepatitis infection or other active hepatitis or clinically significant moderate to severe cirrhosis; 9. Patients who currently have hypertension that cannot be controlled by medication;