Peregrine Provides Update on HCV Clinical Program

Peregrine Pharmaceuticals, Inc.

today provided an update from its randomized Phase II bavituximab study in patients infected with genotype-1 chronic hepatitis C virus. Patients were randomized in the three-arm study to receive one of two doses of bavituximab (0.3mg/kg or 3mg/kg) or pegylated interferon alpha-2a, in combination with ribavirin. The goals of the study were to determine if bavituximab plus ribavirin has a better safety profile as compared to interferon plus ribavirin, to confirm that the combination of bavituximab and ribavirin has antiviral activity defined as 12 week early virologic response(1) and to compare antiviral activity of peg-interferon plus ribavirin versus bavituximab plus ribavirin. A preliminary data analysis indicates that the combination of bavituximab and ribavirin appeared safe and well tolerated with patients reporting fewer side effects than in the interferon-containing arm. Initial data from the study also indicated that both dose levels of bavituximab with ribavirin demonstrated antiviral activity, however the antiviral effects in patients receiving the 0.3 mg/kg dosing level were more pronounced. A comparison of the viral data indicated that the kinetics of antiviral activity were different between the interferon and bavituximab treatment groups with a high percentage of those patients achieving EVR in the interferon arm of the study doing so between week 4 and 8 and the majority of patients achieving EVR in the bavituximab groups doing so at the week 12 end of study timepoint. More patients had achieved EVR in the interferon-containing group by the end of the study, however based on the nature of late EVR development in the bavituximab containing arms at the very end of the 12 week trial, a longer-term evaluation is needed to adequately compare the effectiveness of bavituximab and interferon. The company plans to present full results from the study at a medical conference in 2012.