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Alkermes Presents Positive Preclinical Data on Naltrexone for Extended-Release Injectable Suspension at Annual Meeting of Controlled Release Society

--Injectable Extended-Release Formulation Improved Efficacy Compared to Oral Therapy --

CAMBRIDGE, Mass.--(BUSINESS WIRE)--July 14, 2008--Alkermes, Inc. (NASDAQ: ALKS) today announced positive preclinical results which demonstrated naltrexone for extended-release injectable suspension (XR-NTX) was more effective in an animal model of substance abuse compared to oral naltrexone therapy. The data were presented in an oral session at the 35th Annual Meeting and Exposition of the Controlled Release Society in New York City.

"These are very encouraging results as they suggest that the formulation and method of administration are important and that extended-release injectable formulations, in particular, may provide advantages over oral therapies," stated Daniel Deaver, Ph.D., vice president, non-clinical development of Alkermes. "We hope these data and continued research will help us to further elucidate the mechanistic reasons for these differences."

The study results presented included an evaluation of the effects of XR-NTX compared to naltrexone administered orally and subcutaneously in a model of amphetamine reward in rodents. Data showed that treatment with XR-NTX weakened the rewarding effects of amphetamine in the brain for at least two weeks. At day 14, amphetamine reward was reduced by 70 percent in rodents treated with XR-NTX, compared to no effect for oral and subcutaneous naltrexone. These data suggest that the extended-release injectable formulation of XR-NTX may utilize a unique mechanism of action that differentiates it from oral and subcutaneous naltrexone, thereby allowing for enhanced inhibition of brain stimulation reward by amphetamines.

About Alkermes

Alkermes, Inc., a biotechnology company committed to developing innovative medicines to improve patients' lives, manufactures RISPERDAL(R) CONSTA(R) for schizophrenia and developed and manufactures VIVITROL(R) for alcohol dependence. Alkermes' robust pipeline includes extended-release injectable, pulmonary and oral products for the treatment of prevalent, chronic diseases, such as central nervous system disorders, addiction and diabetes. Headquartered in Cambridge, Massachusetts, Alkermes has research and manufacturing facilities in Massachusetts and Ohio. For more information about Alkermes, visit

Certain statements set forth above may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to the potential advantage of extended-release injectable formulations over oral therapies. Although the company believes that such statements are based on reasonable assumptions within the bounds of its knowledge of its business and operations, the forward-looking statements are neither promises nor guarantees and the company's business is subject to significant risk and uncertainties and there can be no assurance that its actual results will not differ materially from its expectations. For further information with respect to factors that could cause the company's actual results to differ materially from expectations, reference is made to the reports the company filed with the Securities and Exchange Commission under the Securities Exchange Act of 1934, as amended. The forward-looking statements made in this release are made only as of the date hereof and the company disclaims any intention or responsibility for updating predictions or financial expectations contained in this release.

VIVITROL(R) is a registered trademark of Cephalon, Inc.; RISPERDAL(R) CONSTA(R) is a registered trademark of Janssen-Cilag group of companies.

CONTACT: Alkermes, Inc. Rebecca Peterson, 617-583-6378 Corporate Communications
SOURCE: Alkermes, Inc.


Posted: July 2008