Randomized phase III study of gemcitabine, cisplatin plus S-1 versus gemcitabine, cisplatin for advanced biliary tract cancer (KHBO1401- MITSUBA).

GCS is the first regimen which demonstrated survival benefits as well as higher RR over GC in a randomized phase III trial and could be the new first-line standard chemotherapy for advanced BTC. To exploit the advantage of its high RR, GCS is now tested in the neoadjuvant setting in a randomized phase III trial for potentially resectable BTC.