Addition of bevacizumab to first-line FOLFOX4 and overall survival in patients with metastatic colorectal cancer.

Abstract

610 Background: In our previous report, addition of bevacizumab (BV) to the FOLFOX4 regimen appeared to significantly improve response rate, progression-free survival and overall survival in first-line treatment for patients with metastatic colorectal cancer (mCRC) (Suenaga M, et al. ASCO-GI 2011 [abstr 588]). Update results met median overall survival, and statistical analysis of survival was performed. Methods: An observational cohort study was carried out on all eligible patients scheduled to receive FOLFOX4 (n = 128) or FOLFOX4+BV (n = 85) between 2005 and 2007, 2007 and 2009, with a median follow-up time of 20.4 months vs. 30.2 months, respectively. Predefined efficacy endpoints were treatment characteristics, response rates, progression-free survival, and overall survival in the periods of time observed. Results: Median progression-free survival was 9.9 months (95% CI, 8.4-11.4) in the FOLFOX4- and 17 months (95% CI, 11.8-22.3) in the FOLFOX4+BV-treated patients (p=0.002). Median overall survival times were 20.5 months (95% CI, 16.9-24) and 38.8 months (95% CI, 32.9-44.8) in the two groups, respectively (p<0.001). In the ECOG PS 0 population, progression-free survival in the FOLFOX4 and FOLFOX4+BV groups was 11 months and 17 months with a hazard ratio of 0.63 (95% CI, 0.44-0.89) in favour of FOLFOX4+BV, similarly in OS with a hazard ratio of 0.53 (95% CI, 0.36-0.77). Subgroup population received 5-FU plus leucovorin (FL) as maintenance during oxaliplatin discontinuation due to adverse events had longer PFS or OS in both groups, though no significance. PFS were 14.7 and 21.6 months, and OS were 29 and 45.9 months, respectively. Secondary resection was performed more in FOLFOX4+BV (11.8%) than FOLFOX4 (3.9%) patients. Conclusions: These data indicate potential survival benefits from the addition of BV to the FOLFOX4 regimen as first-line treatment for mCRC. Maintenance using FL after discontinuation of oxaliplatin due to adverse events appeared to be an essential factor for better survival.