Peregrine Pharmaceuticals to initiate new Bavituximab HCV trial

May 18 2007

Peregrine Pharmaceuticals has announced it has filed a new clinical trial protocol with the FDA to study bavituximab in patients co-infected with HCV and the human immunodeficiency virus (HIV).

The multi-center trial will initially be conducted at Saint Michael's Medical Center in Newark, NJ under the direction of Dr. Stephen Smith, director of the Peter Ho Memorial Clinic, the largest HIV/AIDS treatment facility in the state.

"Chronic co-infection with the hepatitis C virus affects a significant proportion of our HIV patients, yet current HCV therapies are often ineffective or poorly tolerated," said Dr. Smith. "These patients are particularly vulnerable since co-infection is associated with more aggressive progression of HCV-associated liver disease. We look forward to the opportunity to study bavituximab in co-infected patients so we can begin to assess whether its distinctive immunotherapeutic mechanism might be of value in treating this underserved population."

The new study is an open-label, dose escalation study designed to assess the safety and pharmacokinetics of bavituximab in approximately 24 patients chronically infected with HCV and HIV. Patient cohorts will receive ascending dose levels of bavituximab weekly for up to 8 weeks. HCV and HIV viral titers and other biomarkers will be tracked, although they are not formal study endpoints.

"We believe that bavituximab's unique targeting mechanism has the potential to act on both HCV and HIV virus infections," said Steven W. King, president and CEO of Peregrine. "Greater understanding of bavituximab's activity in the HCV/HIV co-infection setting should help guide our future development efforts, potentially allowing us to treat an HCV patient population typically excluded from clinical studies. We are especially pleased to be pursuing this clinical trial in collaboration with Dr. Smith, a leader in researching infectious diseases and in providing high quality care to people with HIV."

In the United States alone, an estimated 300,000 individuals are co-infected with HIV and HCV, representing up to 30% of all HIV-infected patients. Co-infected patients have been shown to have a lower response to interferon/ribavirin HCV regimens and the adverse effects of these regimens can be especially problematic for some HIV patients.

Bavituximab is a monoclonal antibody in a new class of anti- phosphotidylserine (PS) immunotherapeutics that targets and binds to cellular components that are normally not present on the outside of cells, but which become exposed on certain virally infected cells and on the surface of enveloped viruses, including both HCV and HIV. Bavituximab helps stimulate the body's immune defenses to destroy both the virus particles and the infected cells. Since bavituximab's PS target comes from the host and not the virus, bavituximab is expected to be less susceptible to the development of anti-viral resistance than many other therapies. Bavituximab has successfully completed Phase la and lb clinical trials as monotherapy in patients with chronic HCV infection, which showed that the drug is well tolerated and demonstrated encouraging signs of anti-viral activity.