PURPOSE: This randomized phase III trial compared the efficacy and safety of capecitabine with or without bevacizumab, a monoclonal antibody to vascular endothelial growth factor, in patients with metastatic breast cancer previously treated with an anthracycline and a taxane. PATIENTS AND METHODS: Patients were randomly assigned to receive capecitabine (2,500 mg/m2/d) twice daily on day 1 through 14 every 3 weeks, alone or in combination with bevacizumab (15 mg/kg) on day 1. The primary end point was progression-free survival (PFS), as determined by an independent review facility. RESULTS: From November 2000 to March 2002, 462 patients were enrolled. Treatment arms were balanced. No significant differences were found in the incidence of diarrhea, hand-foot syndrome, thromboembolic events, or serious bleeding episodes between treatment groups. Of other grade 3 or 4 adverse events, only hypertension requiring treatment (17.9% v 0.5%) was more frequent in patients receiving bevacizumab. Combination therapy significantly increased the response rates (19.8% v 9.1%; P = .001); however, this did not result in a longer PFS (4.86 v 4.17 months; hazard ratio = 0.98). Overall survival (15.1 v 14.5 months) and time to deterioration in quality of life as measured by the Functional Assessment Of Cancer Treatment--Breast were comparable in both treatment groups. CONCLUSION: Bevacizumab was well tolerated in this heavily pretreated patient population. Although the addition of bevacizumab to capecitabine produced a significant increase in response rates, this did not translate into improved PFS or overall survival.