First-line trifluridine/tipiracil plus bevacizumab in patients with unresectable metastatic colorectal cancer: final survival analysis in the TASCO1 study

BACKGROUND: Therapeutic options are limited in patients with unresectable metastatic colorectal cancer (mCRC) ineligible for intensive chemotherapy. The use of trifluridine/tipiracil plus bevacizumab (TT-B) in this setting was evaluated in the TASCO1 trial; here, we present the final overall survival (OS) results. METHODS: TASCO1 was an open-label, non-comparative phase II trial. Patients (n = 153) were randomised 1:1 to TT-B (trifluridine/tipiracil 35 mg/m2 orally twice daily on days 1-5 and 8-12, and bevacizumab intravenously 5 mg/kg on days 1 and 15 of each 28-day cycle) or capecitabine plus bevacizumab (C-B; capecitabine, 1250 mg/m2 orally twice daily on days 1-14 and bevacizumab 7.5 mg/kg intravenously on day 1 of each 21-day cycle). Final OS was analysed when all patients had either died or withdrawn from the study. Adjusted multivariate regression was used to investigate the effects of pre-specified variables on OS. RESULTS: At 1 September 2020, median OS was 22.3 months (95% CI: 18.0-23.7) with TT-B and 17.7 months (95% CI: 12.6-19.8) with C-B (adjusted HR 0.78; 95% CI: 0.55-1.10). No variables negatively affected OS with TT-B. Safety results were consistent with prior findings. CONCLUSIONS: TT-B is a promising therapeutic regimen in mCRC patients ineligible for intensive chemotherapy. CLINICAL TRIAL INFORMATION: NCT02743221 (clinicaltrials.gov).