Bevacizumab (Bev) in combination with XELOX or FOLFOX4: Updated efficacy results from XELOX-1/ NO16966, a randomized phase III trial in first-line metastatic colorectal cancer

4028 Background: NO16966 is the first phase III trial to evaluate the combination of Bev with oxaliplatin-based chemotherapy (FOLFOX4 or the XELOX regimen) in the first-line setting. Methods: 1401 pts were randomized to receive FOLFOX4 (oxaliplatin, 5-FU, leucovorin as described previously) or XELOX (oxaliplatin 130mg/m 2 iv, capecitabine 1000mg/m 2 bid oral d1–14, q3w) plus Bev (5mg/kg q 2 weeks for FOLFOX, 7.5mg/kg q 3 weeks for XELOX) or Placebo in a 2x2 factorial design. Results: The addition of Bev to oxaliplatin-based chemotherapy demonstrated a significant benefit in terms of PFS in the primary analysis (HR 0.83; 97.5% CI 0.72- 0.95, p=0.0023). Prespecified analysis of PFS on treatment (defined as progressive disease or death within 28 days from the last dose of study treatment) and PFS analysis based on tumor assessments by an independent review committee (IRC) were consistent with the benefit observed in the primary analysis. PFS results are shown in Table 1 . 34% of patients have died and the median follow-up for survival at this time is 18.6 months. Mature overall survival data will be presented at the meeting. Conclusions: This large, international phase III trial demonstrates that the addition of Bev to oxaliplatin-based chemotherapy regimens significantly improves PFS. Table: see text Table: see text