A phase II study of FOLFOXIRI plus bevacizumab as initial chemotherapy for patients with untreated metastatic colorectal cancer: TRICC1414 (BeTRI)

Purpose: FOLFOXIRI plus bevacizumab is regarded as a first-line therapeutic option for selected patients with metastatic colorectal cancer (mCRC). Our aim was to assess the efficacy and safety of induction treatment with FOLFOXIRI plus bevacizumab in patients with untreated mCRC harboring UGT1A1 wild (*1/*1), or single-hetero (*1/*6 or *1/*28) genotypes. Methods: Twelve cycles of FOLFOXIRI plus bevacizumab were administered to patients with untreated mCRC. The primary endpoint was the overall response rate (ORR) assessed by central independent reviewers. Secondary endpoints included time to treatment failure (TTF), progression-free survival (PFS), overall survival (OS), relative dose intensity (RDI), R0 resection rate, and safety. The exploratory objectives were early tumor shrinkage (ETS) and depth of response (DoR). Results: Of the 47 patients enrolled, 46 and 44 patients were eligible for the safety and efficacy analysis, respectively. The primary endpoint was met. The ORR was 63.6% (95% CI 47.8–77.6). At a median follow-up of 25.4 months, median TTF, PFS, and OS was 8.1, 15.5, and 34.4 months, respectively. The median RDI of 5-fluorouracil, irinotecan, oxaliplatin, and bevacizumab was 72, 69, 62, and 71%, respectively. R0 resection rate was 22.7%. Grade 3 or higher adverse events (≥ 10%) included neutropenia (65.2%), febrile neutropenia (26.1%), leukopenia (23.9%), anorexia (10.9%), nausea (10.9%), and diarrhoea (10.9%). No treatment-related deaths were observed. ETS and DoR were 70.5 and 45.4%, respectively. Conclusions: FOLFOXIRI plus bevacizumab induction treatment of Japanese patients was shown to be beneficial and manageable, although caution is required since the treatment causes febrile neutropenia.