RecruitingPhase 2Drug trialA Single-arm, Multicenter, Exploratory Study of Adebrelimab Combined With Apatinib and Systemic Chemotherapy for Initially Unresectable Biliary Tract CancerThis is an exploratory and prospective study, with the research subjects being patients with initially untreated and unresectable biliary tract tumors. The efficacy and safety of the treatment regimen consisting of Adebrelimab monoclonal antibody combined with targeted therapy and systemic chemotherapy were investigated.