Phase II trial of an alternating regimen consisting of first-line mFOLFOX6 plus bevacizumab and FOLFIRI plus bevacizumab for patients with metastatic colorectal cancer: FIREFOX plus bevacizumab trial (KSCC0801)

Objectives: The purpose of this phase II study was to explore the efficacy and safety of an alternating regimen consisting of folinic acid, 5-fluorouracil (5-FU) and oxaliplatin (mFOLFOX6) plus bevacizumab, and folinic acid, 5-FU and irinotecan (FOLFIRI) plus bevacizumab as first-line treatment for patients with metastatic colorectal cancer. Methods: Fifty-two patients with metastatic colorectal cancer received an alternating regimen consisting of four cycles of mFOLFOX6 plus bevacizumab followed by four cycles of FOLFIRI plus bevacizumab until disease progression. The primary endpoint was progression-free survival. Results: The median age was 60 years (range 37–75 years). Median progression-free survival was 14.2 months (95 % confidence interval [CI] 10.6–16.3) and median overall survival was 28.4 months (95 % CI 22.6–39.1). The overall response rate was 60.0 % (95 % CI 45.2–73.6). Regarding toxicity, the commonest grade 3–4 hematological adverse events were neutropenia (34.6 %) and leukopenia (7.7 %), and the commonest grade 3–4 non-hematological adverse events were anorexia (13.5 %), fatigue (9.6 %), nausea (9.6 %), and vomiting (9.6 %). Bevacizumab-related grade 3–4 adverse events included hypertension (1.9 %) and thrombosis (1.9 %). Conclusions: An alternating regimen consisting of mFOLFOX6 plus bevacizumab and FOLFIRI plus bevacizumab is an effective and well-tolerated first-line chemotherapy combination for patients with metastatic colorectal cancer.