Camrelizumab Combined With Apatinib and Capecitabine in Patients With Advanced Biliary Tract Cancer.

Inclusion Criteria:

* Aged 18-70 years old, both genders.
* Conform to the histological or cytological confirmation of biliary tract carcinoma，including gallbladder cancers and cholangiocarcinomas.
* Patients have advanced unresectable biliary tract carcinoma, including recurrence or metastasis of BTC after radical resection.
* Patientss who have not received any prior PD-1 inhibitor and Apatinib therapy.
* Patients must have at least 1 lesion that is measurable using RECIST v1.1 criteria.
* Eastern Cooperative Oncology Group Performance Status of 0 or 1within one week before enrollment.
* Life expectancy greater than 3 months.
* Patient must have adequate organ function defined by the study-specified laboratory tests.
* Patient must use acceptable form of birth control while on study.
* Ability to understand and willingness to sign a written informed consent document.

Exclusion Criteria:

* Patients with known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation or planned transplantation.
* Patients with other malignant tumor in the past 5 years (except cured skin basal cell carcinoma and cervical carcinoma).
* History of esophageal variceal bleeding, hepatic encephalopathy, massive ascites and abdominal infection.
* Concurrent medical condition requiring the use of immunosuppressive medications, or immunosuppressive doses of systemic or absorbable topical corticosteroids. Doses \> 10 mg/day prednisone or equivalent are prohibited within 14 days before study drug administration.
* Known history of hypersensitivity to any components of the camrelizumab, apatinib and Capecitabine formulation, or other antibody formulation.
* Patients who may receive live vaccine during the study, or previous had vaccination within 4 weeks.
* Known or occurrence of central nervous system (CNS) metastases or hepatic encephalopathy.
* Peripheral neuropathy\> Grade 1.
* Patients with any active autoimmune disease or history of autoimmune disease.
* History of immunodeficiency or human immunodeficiency virus (HIV) infection.
* Clinically significant cardiovascular and cerebrovascular diseases, including but not limited to severe acute myocardial infarction within 6 months before enrollment, unstable or severe angina, or coronary artery bypass surgery, Congestive heart failure (New York heart association (NYHA) class \> 2), ventricular arrhythmia which need medical intervention.
* Hypertension and unable to be controlled within normal level following treatment of anti-hypertension agents (within 3 months): systolic blood pressure \> 140 mmHg, diastolic blood pressure \> 90 mmHg.
* Coagulation abnormalities (INR\>1.5 or APTT\>1.5×ULN), with bleeding tendency or are receiving thrombolytic or anticoagulant therapy.
* History of hereditary or acquired bleeding and thrombotic tendency, such as hemophilia, coagulopathy, thrombocytopenia, hypersplenism, etc.
* Patients with obvious cough blood or hemoptysis volume of half teaspoon (2.5 ml) or more within 2 months before entering the study.
* Have significant clinically significant bleeding symptoms or have a clear bleeding tendency within 3 months before entering the study, such as gastrointestinal bleeding, hemorrhagic gastric ulcer, fecal occult blood++ and above at baseline, or vasculitis, etc.
* Previous Arterial/venous thrombosis events within 6 months.
* Required for long-term anticoagulant therapy with warfarin or heparin, or long-term antiplatelet therapy (aspirin ≥300 mg/day or clopidogrel ≥75 mg/day).
* Severe infection within 4 weeks before the first medication (e.g. need for intravenous antibiotics, antifungal or antiviral drugs), or active infection or an unexplained fever \> 38.5°C during screening visits or on the first scheduled day of dosing.
* Participated in any other drug clinical study within 4 weeks before the first administration, or no more than 5 half lives from the last administration.
* Known history of psychotropic drug abuse or drug abuse.
* Pregnant and lactating women. Any other medical, psychiatric, or social condition deemed by the investigator to be likely to interfere with a subject's rights, safety, welfare, or ability to sign informed consent, cooperate, and participate in the study or would interfere with the interpretation of the results.