Randomized phase II study of gemcitabine plus S-1 combination therapy vs. S-1 in advanced biliary tract cancer: Japan Clinical Oncology Group Study (JCOG0805).

A randomized Phase II selection design trial comparing gemcitabine plus S-1 combination therapy with S-1 monotherapy for chemo-naïve unresectable or recurrent biliary tract cancer patients was started in Japan. The aim of this trial is to evaluate the efficacy and safety of the two regimens and to determine which is more promising as a test arm regimen to be compared with the current standard regimen, gemcitabine plus cisplatin, in a subsequent Phase III trial. Patients with unresectable or recurrent biliary tract cancer are randomized to either gemcitabine plus S-1 combination therapy arm or S-1 monotherapy arm. A total of 100 patients will be accrued for this study from 18 institutions over 1 year. The primary endpoint is the proportion of 1-year overall survival, and the secondary endpoints are progression-free survival, response rate and adverse events.