Biothera's Imprime PGG™ increased the effectiveness of Avastin(R) (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.

The title of the new Clinical Cancer Research paper is "Yeast-Derived β-Glucan Augments the Therapeutic Efficacy Mediated by Anti-Vascular Endothelial Growth Factor Monoclonal Antibody in Human Carcinoma Xenograft Models." The authors are Carolina Salvador, Bing Li, Richard Hansen, Daniel E. Cramer, Maiying Kong and Jun Yan.

About Imprime PGG™

Imprime PGG is a biological response modifier that enhances specific innate immune cell responses. Biothera has completed two Phase I clinical trials under its cancer Investigational New Drug (IND) application for the use of Imprime PGG in combination with anti-cancer monoclonal antibodies. Under a separate IND, the company also has completed a Phase I/II trial with Imprime PGG in combination with a hematopoietic growth factor.

About Avastin®

Avastin was the first anti-angiogenesis therapy approved by the FDA and with last week's approval, is now approved for the treatment of the three leading causes of cancer death in the U.S.: metastatic colorectal cancer, advanced non-squamous, non-small cell lung cancer and metastatic HER2-negative breast cancer. Avastin is a product of Genentech.

About Biothera, the Immune Health Company

Biothera is a biotechnology company dedicated to improving immune health. The company's primary focus is developing pharmaceuticals that engage the innate immune system to fight cancer.

http://www.biotherapharma.com