A Randomized Multicenter Pivotal Study of CDX-011 (CR011-vcMMAE)in Patients With Metastatic, gpNMB Over-Expressing, Triple Negative Breast Cancer (The METRIC Study)

∙ Among other criteria, patients must meet all of the following conditions to be eligible for the study:

• Diagnosed with metastatic (i.e., cancer that has spread) TNBC

‣ minimal or no expression of estrogen and progesterone receptors (ER/PR) \<10% of cells positive by immunohistochemistry

⁃ HER 2 staining 0 or 1+ by IHC or copy number \<4.0 signals/cell

• Documented progression of disease based on radiographic, clinical or pathologic assessment during or subsequent to the last anticancer regimen received.

• Breast cancer tumor confirmed to express gpNMB. This will be determined by submitting a tissue sample from the advanced (locally advanced/recurrent or metastatic) disease setting to a central laboratory for analysis.

• Received no more than two prior chemotherapy treatments for advanced (locally advanced/recurrent or metastatic) breast cancer.

• Prior chemotherapy treatment must have contained an anthracycline (e.g. doxorubicin or Doxil) if clinically indicated and a taxane (eg: Taxol).

• ECOG performance status of 0 - 1.

• Adequate bone marrow, liver and renal function.