FOLFOXIRI plus bevacizumab (bev) versus FOLFIRI plus bev as first-line treatment of metastatic colorectal cancer (mCRC): Updated survival results of the phase III TRIBE trial by the GONO group.
657 Background: The phase III TRIBE trial met its primary endpoint, by demonstrating that first-line FOLFOXIRI plus bev significantly prolongs PFS, as compared to FOLFIRI plus bev. Also RECIST response rate, early response rate and deepness of response were significantly increased. At the first statistical analysis, with a median follow-up of 32.2 months, OS results were considered preliminary. Methods: Between July 2008 and May 2011, 508 patients were randomized to either FOLFIRI plus bev (arm A, n=256) or FOLFOXIRI plus bev (arm B, n=252). Both treatments were administered for a maximum of 12 cycles followed by 5FU/bev until progression. Results: At a median follow-up of 48.1 months, 374 deaths were recorded (Arm A=200 vs. Arm B=174). Median OS for Arm B vs. Arm A was 29.8 vs. 25.8 months (HR=0.80, 95% CI, 0.65-0.98, p=0.030). Long-term survival rates are reported in Table 1. Treatment effect was consistent across all analyzed subgroups. Among clinical variables, ECOG performance status of 1 or 2, right-sided primary tumor, synchronous metastases, disease not confined to the liver, unresected primary tumor, high Kohne score negatively affected prognosis at univariate analyses. At an exploratory model accounting for these variables, adjusted HR for treatment effect on OS was 0.77 (95% CI, 0.61-0.96, p=0.020). Conclusions: FOLFOXIRI plus bev improves survival of mCRC patients, as compared to FOLFIRI plus bev. The estimated 5-years OS rate of patients treated with FOLFOXIRI plus bev was equal to 24.9%, with an absolute benefit of 12.5% compared to controls. FOLFOXIRI plus bev represents a valuable option for the upfront treatment of mCRC. Clinical trial information: NCT00719797. [Table: see text]