EZN-2208 will be administered by i.v. infusion weekly for 3 weeks in 4-week cycles. Study treatment will be continued until evidence of disease progression, unacceptable toxicity, or withdrawal of the patient's consent for participation in the study.~Approximately 160 patients with previously treated MBC will be enrolled in this study. Eighty patients in each of two cohorts will be evaluated as follows:~AT Cohort - Patients treated with prior anthracycline and taxane as adjuvant or metastatic therapy; no more than 2 prior chemotherapy regimens for MBC~ATX Cohort - Patients treated with prior anthracycline, taxane, and Xeloda® (capecitabine) as adjuvant or metastatic therapy; no more than 4 prior chemotherapy regimens for MBC~After discontinuation of study treatment, patients will receive care as considered appropriate by the investigator. Patients will continue to be followed for disease progression, subsequent anticancer therapy, and survival for at least 6 months after enrollment of the last patient in the study
This is a Phase 2, multicenter, open-label, noncomparative study to evaluate safety,efficacy and of single-agent EZN 2208 administered in patients with previously treated MBC.~After discontinuation of study treatment, patients will receive care as considered appropriate by the investigator. Patients will continue to be followed for disease progression, subsequent anticancer therapy, and survival.