Osta announces promising pre-clinical results on a new cancer drug

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Osta Biotechnologies Inc. announces the results of a pilot pre-clinical efficacy study on its lead anti-cancer therapeutic agent OB-24 in a human melanoma xenograft mouse model. Data from this pre-clinical study showed a statistically significant reduction in tumor volumes in groups treated with OB-24, compared to untreated groups and groups treated with dacarbazine.

Dacarbazine has been commonly used as a single agent for the treatment of metastatic melanoma. Unfortunately, like many standard chemotherapy drugs, dacarbazine has only limited efficacy and numerous side effects, including nausea, fatigue, reproductive toxicity including sterility and birth defects and immunosuppression.

OB-24 was well tolerated with no apparent signs of toxicity in mice at two different dose levels after multiple administrations. These results hold promise that OB-24, either alone or in combination with other chemotherapeutic agents, could become the treatment of choice for treating metastatic and drug-resistant human melanomas.

These findings represent an important milestone in Osta's plan to develop novel targeted agents for the treatment of highly metastatic, aggressive and drug resistant tumors, and provide an important advance towards generating sufficient pre-clinical data in order for the company to progress towards an Investigational New Drug (IND) filing, anticipated in 2009.

OB-24 is based on a family of novel chemical compounds discovered at Queen's University by Dr. Walter Szarek, Professor Emeritus in the Department of Chemistry, and Dr. Kanji Nakatsu, Professor in the Department of Pharmacology and Toxicology.

Drs. Szarek and Nakatsu are very excited about the results obtained in collaboration with Osta's scientific team thus far.

The compounds were exclusively licensed to Osta by PARTEQ Innovations, the technology transfer office of Queen's University. Osta has filed for patent protection on the novel family of compounds and their uses.