The purpose of the study is to determine the overall response to a combination of bavituximab and docetaxel in patients with advanced breast cancer

Inclusion Criteria:

• Adult females over age 18 with life expectancy of at least 3 months
• Histologically or cytologically confirmed locally advanced or metastatic breast cancer
• One and only one prior chemotherapy regimen (no prior docetaxel)
• Measurable disease (at least one target lesion)at least 2 cm in longest diameter (1 cm by spiral CT)
• Adequate hematologic, renal, and hepatic function;

Exclusion Criteria:

• Known history of bleeding diathesis or coagulopathy
• Any current evidence of clinically significant bleeding
• Any history of thromboembolic events
• Concurrent hormone therapy
• Prior immunotherapy or radiotherapy to an area of measurable disease unless disease has recurred after radiotherapy