KRAS mutation status-stratified randomized phase II trial of GEMOX with and without cetuximab in advanced biliary tract cancer (ABTC): The TCOG T1210 trial

4018 Background: Gemcitabine/platinum combination is considered as globally acceptable standard care in patients with ABTC. Two recently published randomized trials showed adding EGFR antagonist, either erlotinib or cetuximab, does not further improve the clinical outcomes of gemcitabine/oxaliplatin (GEMOX)-treated ABTC patients. However, the impact of KRAS mutation status on the results of both studies was not properly addressed. Methods: A prospective, multicenter randomized, phase II trial to evaluate the therapeutic efficacies of adding cetuximab to GEMOX in patients with ABTC, in which eligible patients were stratified by status of KRAS mutation and ECOG PS, and tumor location then randomized to receive either GEMOX (gemcitabine 800 mg/m2, fixed-rate infusion and oxaliplatin 85 mg/m2, i.v., Q 2 weeks) or GEMOX plus cetuximab (500 mg/m2, i.v., Q 2 weeks, C-GEMOX). The primary endpoint was overall response rate (ORR). As an exploratory trial, 120 (60 per arm) patients was estimated to detect a two-tail...