SHR-1210 in Combination With GEMOX in Patients With Advanced BTC

Inclusion Criteria: * Pathology confirmed biliary malignancy, including intrahepatic bile duct carcinoma, extrahepatic bile duct carcinoma, and gallbladder carcinoma. * Age:18-75 years, male or female. * The estimated survival period is more than 3 months. * ECOG 0-1. * There is at least one measurable lesion, according to the RECIST 1.1 standard. * Patients has not been treated by oxaliplatin, gemcitabine and pd-1 / pd-l1 antibody. * Patients who have been treated tegafur or capecitabine as adjuvant chemotherapy or first-line treatment may be selected. Exclusion Criteria: * There were concurrent malignant tumors, except for the cured skin basal cell carcinoma and cervical carcinoma in situ. * Other drug clinical trials have been taken in four weeks. * Patients with a history of central nervous system metastasis or central nervous system metastasis are known before the screening. * Patients with a history of unstable angina. * The urine routine indicated that the urine protein was greater than ++ and confirmed the 24-hour urine protein quantification \>1.0 g. * Have used immune-targeted therapy drugs. * The patient had received a liver transplant. * Having a history of chronic autoimmune diseases such as systemic lupus erythematosus. * Having a history of immunodeficiency, or other acquired, congenital immunodeficiency diseases, or a history of organ transplantation;