Patient enrollment completed in Phase II clinical trial of bavituximab

Sep 9 2009

Peregrine Pharmaceuticals, Inc. (Nasdaq: PPHM) today reported completion of patient enrollment in its Phase II trial evaluating bavituximab in combination with carboplatin and paclitaxel in advanced breast cancer patients. The trial's planned total of 46 patients has been enrolled and patients are currently undergoing treatment and follow-up. The primary objective of the multi-center, open-label study is to assess the overall tumor response to the regimen of bavituximab in combination with carboplatin/paclitaxel. Separately, the company announced issuance of a new U.S. patent with claims covering the use of bavituximab in combination with a broad range of cancer therapeutic agents. Peregrine is currently conducting three separate Phase II studies testing bavituximab in combination with docetaxel or carboplatin and paclitaxel in advanced breast and lung cancer patients. These combination therapies, which have shown promising initial results, are all covered under the claims in the newly issued patent.

"It is fitting that this new U.S. patent protecting the use of bavituximab in combination with a variety of anti-cancer therapeutics has issued as enrollment in each of our three Phase II trials of bavituximab in combination with chemotherapy is either completed or nearing completion," said Steven W. King, president and CEO of Peregrine. "There is considerable evidence that bavituximab and other anti-PS antibodies act synergistically with standard cancer treatments, and the additional protection provided by this new patent further strengthens our intellectual property leadership in the field of PS-targeting therapeutics."

U.S. Patent #7,572,448 covers the therapeutic use of bavituximab and related antibodies in combination with a wide range of anti-cancer agents, including many commonly prescribed chemotherapeutic drugs. This patent was granted to the University of Texas System and is exclusively licensed to Peregrine Pharmaceuticals.

The Phase II trial of bavituximab in combination with carboplatin and paclitaxel in advanced breast cancer patients has a Simon two-stage design. In the first stage, 15 patients with advanced breast cancer were enrolled and treated with the combination regimen. Nine of the 14 (64%) evaluable patients in this cohort demonstrated an objective tumor response according to RECIST criteria, exceeding the pre-specified primary efficacy endpoint needed to expand enrollment in the trial. An additional 31 patients were then enrolled to achieve the planned study total of 46 patients overall.

"Completion of patient enrollment in our second Phase II breast cancer study marks another milestone for the bavituximab cancer program, with two of our three ongoing Phase II trials now having completed enrollment," said Joseph Shan, vice president of clinical and regulatory affairs at Peregrine. "We believe the rapid enrollment experienced in all three of these trials is representative of the enthusiasm of our clinical investigators as well as the need for improved cancer therapies. We look forward to reporting further data from these studies in the upcoming months."

Secondary objectives of the study include measuring time to tumor progression, duration of response, overall patient survival and safety parameters. Patients in the study are evaluated regularly for tumor response according to RECIST criteria. They may continue to receive bavituximab as monotherapy after completion of chemotherapy as long as the cancer does not progress and side effects are acceptable. The trial is being conducted in India according to International Conference on Harmonization (ICH) and Good Clinical Practices (GCP) guidelines.