Multicenter phase Ib/II study of biweekly trifluridine/tipiracil with bevacizumab combination for patients with metastatic colorectal cancer refractory to standard therapies (BiTS study).

647Background: Trifluridine/tipiracil (FTD/TPI) plus bevacizumab (Bmab) combination therapy has shown a promising activity with manageable safety profile in patients (pts) with heavily pretreated metastatic colorectal cancer (mCRC). The aim of this multicenter, phase Ib/II study was to assess the activity and safety of biweekly FTD/TPI with Bmab combination for pts with mCRC who were refractory or intolerant to standard therapies. Methods: Inclusion criteria were ≥ 20 years; histologically confirmed unresectable mCRC; refractory or intolerant to fluoropyrimidine, irinotecan, oxaliplatin, anti-VEGF therapy, and anti-EGFR therapy (for tumors with wild-type RAS); ECOG PS 0 or 1; evaluable lesion according to the RECIST version 1.1. Phase Ib part is designed to determine the recommended phase II dose (RP2D), and pts received the RP2D in phase Ib part were included in efficacy and safety populations. The primary endpoint in phase II part was an investigator assessed progression-free survival rate at 16 weeks (...