A randomized controlled, phase II clinical trial is designed to compare the safety and efficacy of Sintilimab combined with GEMOX ± IBI305 and GEMOX as first-line therapy in advanced intrahepatic cholangiocarcinoma.

Inclusion Criteria:

• Written informed consent should be signed before implementing any trial-related procedures
• Male or female, 18 years old ≤ age ≤ 75 years old
• Histopathologically or cytologically diagnosed as locally advanced intrahepatic cholangiocarcinoma
• No previous systemic treatment, More than 6 months after the end of postoperative adjuvant therapy was allowed
• Expected survival time > 3 months
• At least ≥ 1 measurable lesions per RECIST 1.1
• ECOG PS scores 0-2
• Sufficient organ and bone marrow function
• Urine or serum pregnancy test is negative

Exclusion Criteria:

• Suffered from other malignant tumors in the past 5 years (except Radical basal cell carcinoma of the skin squamous carcinoma of the skin and/or radical resected carcinoma in situ)
• Ampullary tumor
• Received treatment from other clinical trials within 4 weeks before the first dose
• Received any anti-PD-1 antibody, anti-PD-L1/L2 antibody, anti-CTLA4 antibody, or other immunotherapy
• Suffered from severe cardiovascular disease within 12 months before enrollment, such as symptomatic coronary heart disease, congestive heart failure ≥ Grade II, uncontrolled arrhythmia, and myocardial infarction
• Uncontrollable pleural effusion, pericardial effusion or ascites
• Use steroids or other systemic immunosuppressive therapies 4 weeks before enrollment
• Allergic reactions to the drugs used in this study
• HIV antibody positive, active hepatitis B or C (HBV, HCV)
• Known history of allogeneic organ transplantation and allogeneic hematopoietic stem cell transplantation
• other conditions that the investigator deems inappropriate for enrollment.