A multicenter, open-label, phase I study of nivolumab alone or in combination with gemcitabine plus cisplatin in patients with unresectable or recurrent biliary tract cancer.

306Background: This phase 1 study evaluated the safety and efficacy of the immune checkpoint inhibitor nivolumab (monotherapy or combined with chemotherapy) in Japanese patients with biliary tract cancer (BTC). Methods: In the monotherapy cohort (N = 30), patients with unresectable/recurrent BTC refractory or intolerant to gemcitabine-based treatment regimens received nivolumab monotherapy (240 mg, 2-week intervals). In the combined therapy cohort (N = 30), chemonaive patients with unresectable/recurrent BTC received nivolumab (240 mg, 2-week intervals) plus cisplatin-gemcitabine chemotherapy. The primary objective was tolerability and safety. Secondary efficacy endpoints included overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) (central assessment). Results: The most frequently reported nivolumab-related adverse events were decreased appetite (5/30, 17%), malaise (4/30, 13%), and pruritus (4/30, 13%) in the monotherapy cohort, and malaise (8/30, 27%) and decreased ...