Peregrine Antibody Shows Combo Benefit in Preclinical Model

Peregrine Pharmaceuticals will present data at the Society for Immunotherapy of Cancer (SITC) Annual Meeting showing that phosphatidylserine (PS)-targeting antibodies reactivate tumor immunity at multiple levels and that these antibodies, when combined with an anti-CTLA-4 antibody yielded enhanced anti-tumor activity in a preclinical model of melanoma. Peregrine is planning to start a Phase III trial in second-line non-small cell lung cancer (NSCLC) with its lead PS-targeting antibody bavituximab by year-end.

Scientists from Peregrine and The University of Texas Southwestern Medical Center examined the anti-tumor response of a PS-targeting antibody equivalent to bavituximab and anti-CTLA-4 combination therapy in a mouse melanoma model. Results showed that the group that received the combination resulted in superior tumor growth inhibition than with either antibody alone, with no additional toxicity following multiple treatment doses. In addition, histopathological analysis showed the combination produced more inflammatory cell infiltration and tumor destruction than anti-CTLA-4 alone.

Peregrine is actively working towards initiating a clinical trial in the coming months to further investigate the potential synergistic effects of bavituximab and an approved immunotherapy in patients with melanoma. Yervoy (ipilimumab) from Bristol-Myers Squibb is an FDA-approved anti-CTLA-4 antibody.