Final analysis revealed that the addition of bevacizumab to IFL significantly improved OS (primary endpoint, HR: 0.66, p < 0.001), PFS (HR: 0.54, p < 0.001) and RR (44.8% vs 34.8%, p = 0.004). The planned analysis comparing patients treated with 5-FU/LV plus bevacizumab with those concurrently enrolled in the IFL plus placebo group, revealed no significant differences between arms in terms of OS (HR:
0.82 [0.59-1.15], selleck chemicals llc p = 0.25), PFS (HR: 0.86 [0.60-1.24], p = 0.42) and RR (49% vs 37%, p = 0.66) . The outcome reported in the 5-FU/LV plus bevacizumab arm was consistent with other experiences that explored the use of bevacizumab in combination with 5-FU/LV. In a phase II randomized study, including 104 patients, the combination of bevacizumab with 5-FU/LV resulted in longer time to disease progression (TTP, median TTP: 9.0 months [5.8-10.9] vs 5.2 months [3.5-5.6]) and in better, but not significantly, RR (40% [24-58] vs 17% [7–23]-34) and OS (median OS: 21.5 months [17.3-undetermined] vs 13.8 months [9.1-23]) . Similar results were R788 chemical structure obtained in another phase II trial, randomizing 209 patients, that were not optimal candidates for irinotecan-containing regimens, to receive 5-FU/LV plus or minus bevacizumab. Patients treated with the antiangiogenic obtained a significantly
ABT-888 cost longer PFS (HR: 0.50 [0.34-0.73], p = 0.0002) and OS, that was the primary endpoint of the study (HR: 0.79 [0.56-1.10], p = 0.160) . Bevacizumab has been also studied in combination with oxaliplatin-based regimens in the NO16966 study, where about 1400 mCRC patients were randomly assigned according to a 2 × 2 design, to receive either FOLFOX or XELOX plus bevacizumab Clomifene or placebo as first-line treatment . The addition of bevacizumab was associated with significantly longer PFS (HR: 0.83 [0.72-0.95], p = 0.0023), that translated into
a trend toward better OS, though not reaching the statistical significance (HR: 0.89 [0.76-1.03], p = 0.077). The magnitude of the effect of bevacizumab seemed less prominent in this experience, when compared with results achieved in the AVF2107 study. The frequent discontinuation of the anti-VEGF together with chemotherapy before disease progression and not for bevacizumab-related toxicity was suggested by authors as a possible explanation for such finding. On the basis of these results, the choice of bevacizumab in the routine upfront approach to the treatment of mCRC is extremely frequent. In fact, it has been demonstrated relatively safe in association with both irinotecan-  and oxaliplatin-containing regimens  and its specific toxicity profile appears manageable, by applying appropriate clinical selection criteria . Moreover, differently from the anti-EGFR antibodies, the anti-VEGF may be proposed to all patients, without any molecular restriction. However, in spite of its wide use, the magnitude of the benefit derived by the addition of bevacizumab to conventional cytotoxics is still controversial.