Ueno M, et al. - Among Japanese patients with biliary tract cancer, researchers evaluated the safety and tolerability of the immune checkpoint inhibitor nivolumab, as monotherapy or combined with chemotherapy. For this investigation, nivolumab monotherapy (240 mg every 2 weeks; monotherapy cohort) was given to subjects with unresectable or recurrent biliary tract cancer that was refractory or intolerant to gemcitabine-based treatment regimens. Nivolumab (240 mg every 2 weeks) and cisplatin (25 mg/m2) plus gemcitabine (1,000 mg/m2) chemotherapy (combined therapy cohort) were administered to chemotherapy-naive subjects with unresectable or recurrent biliary tract cancer. Decreased appetite, malaise, pruritus, neutrophil count decrease were the most frequently reported treatment-related adverse events in the monotherapy group. In the combined therapy group, platelet count decrease were the most frequently reported treatment-related adverse events. In patients with unresectable or recurrent biliary tract cancer, nivolumab had a manageable safety profile and signs of clinical activity.