Regorafenib (BAY 73-4506) was assessed in metastatic colorectal cancer in the phase III randomized CORRECT trial. 760 metastatic colorectal cancer patients were recruited after the failure of all standard therapies.~Given the promising efficacy and favorable tolerability profile of mGEMOX and the potential benefits of targeting the VEGF and Ras/Raf pathway, we propose to assess the combination of Regorafenib with mGEMOX in advanced digestive cancer.~This study is to determine the Regorafenib Dose (RD) for the phase II trial of Regorafenib administered in combination with mGEMOX in patients with advanced biliary tract cancer.~The phase I study of Regorafenib in advanced colorectal cancer showed a pronounced interindividual variability of drug exposition. Furthermore, the CORRECT study shows a large pharmacological variability of plasma concentration for Regorafenib and its metabolites. In this study, we propose to explore the pharmacological variability and his potential heritability by the therapeutic drug monitoring of Regorafenib. The objective is to understand and to control the pharmacological variability of Regorafenib and finally to predict the therapeutic response or the toxicity, especially in a population of patients with biliary tract cancer.~In addition, we will complete this study by exploring the gene variants of drug metabolism. The genes are POR (P450 OxidoReductase,) NR1I2 (Nuclear Receptor subfamily 1, group I, member 2) and a part of the regulatory sequences of CYP3A4.
This study is to determine the Regorafenib Dose (RD) for the phase II trial of Regorafenib administered in combination with mGEMOX in patients with advanced biliary tract cancer.