A Study of AMG 706 or Bevacizumab, in Combination With Paclitaxel Chemotherapy, as Treatment for Breast Cancer

Inclusion Criteria:

* Histologically or cytologically confirmed adenocarcinoma of the breast with locally recurrent or metastatic disease.
* Measurable disease by RECIST guidelines.
* Tumor (primary or metastatic) must be HER2 negative.
* Adequate organ and hematologic function. Exclusion:
* Taxane treatment within 12 months prior to registration.
* Prior chemotherapy for locally recurrent or metastatic breast cancer (prior endocrine therapy is permitted).
* Prior radiation therapy, radiofrequency ablation, percutaneous cryotherapy or hepatic chemoembolization on all sites of measurable disease.
* Current or prior history of central nervous system metastases.
* Peripheral neuropathy ≥ grade 2 (CTCAE v3.0) at registration.
* History of arterial or venous thrombosis within 1 year prior to registration.
* History of bleeding diathesis or bleeding within 14 days of registration.
* Uncontrolled hypertension (systolic \>145 mmHg; diastolic \>85 mmHg).
* Clinically significant cardiac disease within 12 months of registration.
* Known HIV positive, hepatitis C positive or hepatitis B surface antigen positive.
* Prior treatment with VEGFr targeted therapies.