Biothera’s Imprime PGG™ increased the effectiveness of Avastin? (bevacizumab), a monoclonal antibody approved for the treatment of metastatic colorectal, breast and non-small cell lung cancer, according to a new preclinical study published in the current issue of Clinical Cancer Research.
Researchers in the Tumor Immunobiology Program of the James Graham Brown Cancer Center, University of Louisville, Kentucky, studied the synergistic effects of Imprime PGG in combination with Avastin in a xenograft mouse model where human ovarian cancer cells were implanted into the mice.
In the treatment group receiving both Imprime PGG and Avastin, 86% of the mice survived 100 days compared with only 43% in the group receiving Avastin alone.
“Our study is the first to demonstrate that Avastin, an anti-angiogenic agent, co-administered with Imprime PGG, an agent that enhances innate immune effector cell function, results in synergistic anti-tumor effects,” said Carolina Salvador, M.D., a clinical instructor at the James Graham Brown Cancer Center. “This type of combination strategy has significant clinical implications and deserves further investigation.”
“These results are consistent with our previous research with Imprime PGG and various monoclonal antibodies in numerous cancer indications,” said Daniel K. Conners, president of Biothera’s Pharmaceutical Group. “We are now working to demonstrate the safety and efficacy of these novel cancer therapies in the clinic.”
Biothera is currently conducting a clinical trial with metastatic colorectal cancer patients receiving a combination therapy of Imprime PGG, Erbitux® (cetuximab), a monoclonal antibody from ImClone Systems, and Irinotecan, a chemotherapy drug from Pfizer.
The results of the trial are expected later in 2008. The company also plans to initiate a clinical study in lung cancer patients this year using a combination of Imprime PGG, Avastin and two chemotherapy drugs.