A Trial of Recaticimab and Adebrelimab in Combination With Chemotherapy in Patients With Unresectable BTC

Inclusion Criteria: * 1\. Provided informed consent and sign the informed consent form; * 2\. Male or female, Aged 18-75 years (counted on the date of signing informed consent); * 3\. Histologically confirmed unresectable advanced or metastatic biliary tract adenocarcinoma, including cholangiocarcinoma (intrahepatic or extrahepatic) and gallbladder carcinoma.; * 4\. The patient is not a candidate for surgery, or the disease has progressed after prior surgery and/or local treatment. * 5\. No previous systematic treatment for advanced BTC. Exceptions include patients who relapsed more than 6 months after adjuvant chemotherapy following radical resection. Local regional therapy (including but not limited to surgery, radiotherapy, hepatic artery embolization, TACE, hepatic arterial infusion, radiofrequency ablation, cryoablation or percutaneous ethanol injection) must have been completed at least 4 weeks prior to baseline radiological scanning, and any toxicity (except alopecia) induced by local regional therapy must have resolved to ≤ Grade 1 in accordance with National Cancer Institute - Common Terminology Criteria for Adverse Event version 5.0 (NCI-CTCAE v5.0); * 6\. No prior treatment with immune-mediated therapy, including but not limited to other anti-CTLA-4, anti-PD-1, anti-PD-L1, and anti-PD-L2 antibodies, with the exception of therapeutic anticancer vaccines and adjuvant immunotherapy administered after curative resection * 7\. Have at least one measurable lesion (in ac…