Bevacizumab with FOLFOXIRI (irinotecan, oxaliplatin, fluorouracil, and folinate) as first-line treatment for metastatic colorectal cancer: a phase 2 trial

Background The FOLFOXIRI (irinotecan, oxaliplatin, fluorouracil, and folinate) regimen has been shown to be better than FOLFIRI (fluorouracil, folinate, and irinotecan) in a phase 3 trial in patients with metastatic colorectal cancer. Results of various studies have shown that the addition of bevacizumab to chemotherapy increases treatment efficacy. We therefore assessed the safety and activity of the combination of FOLFOXIRI plus bevacizumab in patients with colorectal cancer. Methods In a phase 2 study, patients (aged 18-75 years) with colorectal cancer, which was judged to be unresectable for metastatic disease, were given the combination of intravenous bevacizumab (5 mg/kg on day 1) and intravenous FOLFOXIRI (irinotecan 165 mg/m(2) on day 1, oxaliplatin 85 mg/m2 on day 1, folinate 200 mg/m(2) on day 1, and fluorouracil 3200 mg/m(2) for 48 h continuous infusion starting on day 1 and repeated every 2 weeks) as first-line treatment in seven centres in Italy. Induction treatment (FOLFOXIRI and bevacizumab) was administered for a maximum of 6 months, followed by maintenance treatment with bevacizumab (5 mg/kg intravenously on day 1, repeated every 2 weeks). The primary endpoint was progression-free survival (PFS) at 10 months from study entry in the intention-to-treat population. This study has been completed and is registered with ClinicalTrials.gov, number NCT01163396. Findings From July 2, 2007, to April 1, 2008, 57 patients were enrolled; all patients were assessed for safety and efficacy. Median follow-up time was 28.8 months (95% CI 24.9-32.5). PFS at 10 months was 74% (95% CI 62-85). Main grade 3 or 4 adverse events during induction treatment were neutropenia (n=28 [49%], including one case of febrile neutropenia), diarrhoea (n=8 [14%]), stomatitis (n=2 [4%]), neurotoxicity (n=1 [2%]), deep-vein thrombosis (n=4 [7%]), and hypertension (n=6 [11%]). No treatment-related deaths occurred. Six serious adverse events occurred during the induction treatment: febrile neutropenia (n=1 [2%]), grade 3 diarrhoea with dehydration (n=2 [4%]), grade 4 stomatitis (n=1 [2%]), grade 4 hypertension (n=1 [2%]), and fluorouracil-related cardiac ischaemia (n=1 [2%]). The most common grade 3 or 4 adverse events noted in the 37 patients who received maintenance treatment were hypertension (n=5 [14%]) and neurotoxicity (n=3 [8%]). One case of acute myocardial infarction due to coronary thrombosis was noted during the maintenance treatment. Interpretation Bevacizumab can be safely used with FOLFOXIRI without causing unforeseen adverse events. Treatment achieved promising results in terms of PFS. A phase 3 study for the comparison of FOLFOXIRI plus bevacizumab with FOLFIRI plus bevacizumab is in progress.