A phase II study of bevacizumab with modified OPTIMOX1 as first-line therapy for metastatic colorectal cancer: the TCOG-GI 0802 study

Background Although bevacizumab plus FOLFOX is a standard treatment for metastatic colorectal cancer, oxaliplatin must be withdrawn in many patients because of cumulative neurotoxicity. We postulated that a reduced dose of oxaliplatin and modified treatment schedule would prolong the time to treatment failure and evaluated bevacizumab combined with a modified OPTIMOX1 regimen (mOPTIMOX1, oxaliplatin dose: 85 mg/m(2)). Methods Eligible patients had a histologically confirmed diagnosis of metastatic colorectal cancer and a performance status of 0-1. Patients were excluded if they had grade 1 or higher peripheral sensory neuropathy or had previously received chemotherapy for metastatic colorectal cancer. Patients received bevacizumab plus mFOLFOX6 every 2 weeks for 6 cycles, followed by 12 cycles of a simplified biweekly regimen of leucovorin and fluorouracil (sLV5FU2) plus bevacizumab. Oxaliplatin was then reintroduced, and bevacizumab plus mFOLFOX6 was continued until progressive disease. Results The median duration of disease control was 11.7 months (95 % confidence interval [CI], 9.7-13.5 months). The median overall survival was 23.1 months (95 % CI, 18.8-27.9 months). The overall response rate according to both the RECIST and WHO criteria was 51.3 %. The most common grade 3 or 4 toxicities were neutropaenia (32.5 %), hypertension (17.5 %), leukocytopaenia, sensory neuropathy, and diarrhoea (10.0 %). There were no treatment-related deaths. Conclusions Bevacizumab plus mFOLFOX6 was well tolerated, and patients could continue chemotherapy for longer than with conventional FOLFOX regimens. This regimen might be an effective treatment option for patients with metastatic colorectal cancer.