A Study Evaluating the Efficacy and Safety of Bevacizumab in Combination With Chemotherapy in Untreated Metastatic Breast Cancer (RIBBON 1)

This study includes a blinded treatment phase, an optional open-label post-progression phase, and a survival follow-up phase. During the blinded treatment phase, patients receive chemotherapy and study drug (bevacizumab or placebo) every 3 weeks until disease progression, treatment-limiting toxicity, or death due to any cause. The optional open-label post-progression phase consists of chemotherapy treatment (per investigator discretion) and optional treatment with open-label bevacizumab. Patients who complete the study or who discontinue from treatment (regardless of participation in the optional open-label post-progression phase) will be followed for survival and subsequent anti-cancer therapies every 4 months until death, withdrawal of consent, loss to follow-up, or study termination. Patients who discontinue from treatment during the blinded treatment phase for reasons other than disease progression will have tumor assessments every 9 weeks until documented disease progression or death.