A Phase II Study of Single Tremelimumab With Regular Interval Durvalumab Plus Gemcitabine and Cisplatin in Locally Advanced Unresectable/Metastatic Combined Hepatocellular-cholangiocarcinoma

This is a single arm phase 2 study of Single Tremelimumab with Regular Interval Durvalumab (STRIDE) plus Gemcitabine and Cisplatin (GEMCIS) in locally advanced unresectable/metastatic combined hepatocellular-cholangiocarcinoma (cHCC-CCA). Cycles 1 through 8 will be in 3 week intervals and Cycles 9+ will be in 4 week intervals. Tremelimumab is administered at 300mg intravenously once at Cycle 1. Durvalumab is administered at 1500mg intravenously every 3 weeks for Cycles 1-8, then every 4 weeks for Cycles 9+. Gemcitabine is administered at 1000mg/m\^2 intravenously on Day 1 and Day 8 of Cycles 1-8 only. Cisplatin is administered at 25mg/m\^2 intravenously on Day 1 and Day 8 of Cycles 1-8 only. Subjects will require a visit with appropriate laboratory work prior to the start of each cycle. Disease assessment will occur at screening and then every 9 weeks until the end of Cycle 9. Disease assessments will then occur every 8 weeks. Subjects will continue treatment until progression per RECIST 1.1, toxicity or subject/physician decision. A maximum of 24 months treatment from Cycle 1 Day 1 is allowed.