Study of CR011-vcMMAE to Treat Locally Advanced or Metastatic Breast Cancer

Main Inclusion Criteria:

• Females with confirmed breast cancer
• Age ≥ 18 years
• Eastern Cooperative Oncology Group (ECOG) Performance Status 0 to 2
• Locally advanced or metastatic disease who have received at least two prior chemotherapeutic regimens for breast cancer, as follows:

• At least one regimen must have been for locally advanced or metastatic disease
• Subject must have received an anthracycline, a taxane, and capecitabine in any combination unless the subject was intolerant to or not a candidate for any of these agents
• Hormonal therapy, biologic therapy (such as trastuzumab or bevacizumab), or immunotherapy do not count as one of the 2 regimens
• Subjects with HER2/neu overexpressing tumors must have been treated with trastuzumab except in situations where the subject was intolerant to or not a candidate for trastuzumab
• Documented progressive disease within 6 months of the last regimen
• Adequate bone marrow, renal and liver function
• Signed informed consent

Main Exclusion Criteria:

• Chemotherapy, radiation, hormonal therapy, or bevacizumab within two weeks, or trastuzumab or investigational therapy within three weeks before treatment start
• Neuropathy > NCI-CTCAE Grade 1
• Active brain metastases.
• New York Heart Association class III or IV heart disease
• Unstable angina
• Uncontrolled arrhythmia
• A marked baseline prolongation of QT/QTc interval
• Pregnant or breast-feeding women, and women of childbearing age and potential who are not willing to use effective contraception