Regorafenib versus TAS-102 for refractory metastatic colorectal cancer: A retrospective comparison

Abstract Background Regorafenib and TAS-102 both prolong survival for patients with refractory metastatic colorectal cancer. However, it is unclear which drug should be administered first. Methods We retrospectively evaluated patients who received regorafenib or TAS-102 in two institutions from May 2013 to March 2015. Inclusion criteria were patients refractory or intolerant to fluoropyrimidines, oxaliplatin, irinotecan, anti-vascular endothelial growth factor antibodies, and anti-epidermal growth factor receptor (EGFR) antibodies (if KRAS exon 2 wild-type) and no previous treatment with regorafenib/TAS-102. Results A total of 146 and 54 patients received regorafenib and TAS-102, respectively. The baseline characteristics were similar between the two groups except for a previous history of irinotecan and anti-EGFR therapy and high alkaline phosphatase levels. The median progression-free survival and overall survival were 2.1 months and 6.7 months, respectively, with regorafenib and 2.1 months and 6.5 months, respectively, with TAS-102 (progression-free survival: hazard ratio 1.20, p = 0.27; overall survival: hazard ratio 1.01, p = 0.97). The analysis of overall survival in patients after the approval of TAS-102 in Japan was similar to the overall survival in entire population. The frequencies of hand–foot syndrome and increased aspartate aminotransferase, alanine aminotransferase, and bilirubin were higher and those of neutropenia, leukopenia, anemia, nausea, and febrile neutropenia were lower with regorafenib than with TAS-102. There were no remarkable differences in the efficacy and safety of TAS-102 between patients with and without prior regorafenib, and vice versa. Conclusions Regorafenib and TAS-102 had similar efficacy but different toxicities, which could guide the agent choice.