TGFB1 and cholangiocarcinoma: There is a relatively recent PD-1 and TGF-b inhibitor, bintrafusp alfa or M7824, which proved efficient for immune-resistant CCA, while there is a clinical trial in phase I that is currently performed (NCT02699515), for cases of recurrent CCA after the utilization of first-line chemotherapeutic agents, with 12.7 months, median overall survival [72,73].