Additional data reported in Phase 2 trial of bavituximab for advanced breast cancer

Peregrine Pharmaceuticals reported positive results from its Phase 2 trial evaluating bavituximab in combination with docetaxel in patients with advanced breast cancer. The primary objective of this multi-center, open-label study is to assess the overall response rate to bavituximab and docetaxel. In this trial’s Simon two-stage design, 15 patients were initially enrolled in the study followed by an additional 31 patients after the pre-specified primary efficacy endpoint for expanding the study was met, bringing the total to 46 patients. Recent analysis showed the median progression-free-survival (PFS) of patients enrolled in the initial 15-patient cohort of the study was 7.4 months. Preliminary data at the end of the six planned treatment cycles in the study showed that 28 of 46, or 61%, of all patients enrolled in the trial achieved an objective tumor response according to RECIST criteria. This data compares favorably with data from a published study showing an objective tumor response rate of 41% in a similar patient population receiving the same dosing regimen of docetaxel administered as a single agent.

Secondary objectives of the study include measuring time to tumor progression, duration of response, overall patient survival and safety parameters. Patients may continue to receive bavituximab as monotherapy after completion of chemotherapy as long as the cancer does not progress and side effects are acceptable.

Bavituximab is a monoclonal antibody that binds to the cellular membrane component phosphatidylserine (PS).  PS is exposed on the outside of the cells that line the blood vessels of tumors, creating a specific target for anti-cancer treatments. By binding to PS, bavituximab is believed to help mobilize the body’s immune system to destroy the tumor and the tumor blood vessels.

For more information call (714) 508-6000 or visit www.peregrineinc.com.