Bevacizumab in combination with 5-FU/leucovorin improves survival in patients with metastatic colorectal cancer: A combined analysis

Abstract

3616 Background: Bevacizumab [Avastin (BV)], a recombinant, humanized monoclonal antibody against VEGF, improves survival in combination with chemotherapy for first line treatment of metastatic colorectal cancer (CRC). In a randomized, placebo-controlled phase III study, the addition of BV to irinotecan/5-FU/Leucovorin (IFL) resulted in significant improvement in survival compared with IFL alone (p=0.00004; median survival increased from 15.6 months to 20.3 months). BV has been combined with 5-FU/leucovorin (LV) alone in 3 randomized studies (see table). In the phase III study, a third treatment arm of BV/5-FU/LV was included until the safety of IFL/BV was demonstrated in a pre-specified analysis. BV/5-FU/LV has been studied in 2 randomized phase II studies. In the larger phase II study, patient characteristics were similar to those in the phase III study with the exception that median age was 71 compared with 60 years, and ECOG performance status ≥ 1 was 72% versus 41% of patients. Combining the patient data from these 3 studies allows a more robust evaluation of efficacy and safety of BV/5-FU/LV in comparison with a combined control of 5-FU/LV and IFL. Methods: The combined control group included patients with metastatic CRC randomized to 5-FU/LV or to IFL. The comparator arm included patients randomized in these same studies to BV/5-FU/LV. BV dosing was 5mg/kg every 2 weeks in all patients evaluated. Results: The efficacy results are shown below. There was a 26% reduction in daily risk of death with BV/5-FU/LV compared with 5-FU/LV or IFL alone (hazard ratio 0.742; 95% CI: 0.59, 0.93). Adverse events were consistent with those previously reported. Conclusion: This large combined analysis confirms that the combination of Bevacizumab with 5 FU/LV improves survival and progression-free survival compared with 5-FU/LV or IFL alone.