Study of Immunotherapy Combined With Chemotherapy in Locally Advanced and Metastatic Pancreatic Cancer

Inclusion Criteria: * Histology or cytology confirmed as pancreatic ductal adenocarcinoma; * ECOG 0-1; * adequate organ function (absolute neutrophil count ≥1.5 x 109/L; platelet count ≥100 x 109/L; creatinine \< 1.5 x ULN (upper normal) or calculated creatinine clearance ( CRCI) ≥ 60mL/min; albumin ≥ 30g/L; total bilirubin \<1.5 x ULN; aspartate aminotransferase (AST) \< 2.5 x ULN; alanine aminotransferase (ALT) \< 2.5x ULN; INR or PT \< 1.5x ULN, and aPTT \<1.5x ULN); * no obvious symptoms of jaundice and ascites; * no other serious underlying diseases Exclusion Criteria: * patients with active brain metastases; * history of autoimmune diseases, or need to be treated with corticosteroids and immunosuppressive agents; * past history of unstable angina, symptomatic congestive heart failure, severe arrhythmia, myocardial infarction within 6 months, QT interval prolongation (\>450ms); * other malignant tumors within the last 5 years; * pregnant or lactating women; * NRS ≥ 4 points; * unintentional weight loss ≥ 5% within 1 month before the first dose even if peripheral or central vein nutrition support,