Peregrine’s combination therapy reduces tumor growth by 95%

The study showed that in a mouse model of hormone-refractory prostate cancer, the combination of the bavituximab equivalent antibody 2aG4 and the chemotherapy drug docetaxel significantly decreased the growth of tumors, eliminated detectable metastases and prevented tumor re-growth. This increase in anti-tumor efficacy and anti-metastatic activity was achieved with no apparent increase in toxicity compared to docetaxel alone.

Specifically, in the study 2aG4 administered with docetaxel reduced primary tumor burden by 95%, an anti-tumor effect that was significantly superior to that of the individual treatments administered alone. Treatment with the combination of 2aG4 and docetaxel also reduced the metastatic spread of tumor cells. In animals treated with the combination regimen, none of the treated mice exhibited detectable metastatic lesions, while 100% of the mice treated with a non-specific control antibody, 67% of mice treated with 2aG4 alone and half the mice treated with docetaxel alone exhibited metastatic lesions.

The combination was also superior at preventing tumor re-growth. Survival time was more than doubled in animals receiving combination therapy compared to controls, and was substantially longer than the survival of animals treated with either therapy alone.

Steven King, president and CEO of Peregrine, said: “We are currently testing the combination regimen of bavituximab and docetaxel in a Phase II trial in patients with breast cancer, and we look forward to potentially assessing bavituximab in combination regimens in prostate cancer in future clinical trials.”