Alkermes Presents Positive Preclinical Data on Molecule Designed to Improve Outcomes for Patients Taking Opiod Analgesics

Alkermes Presents Positive Preclinical Data on Novel, Proprietary Molecule Designed to Improve Outcomes for Patients Taking Opioid Analgesics

Second New Program Disclosed During Calendar 2008

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Alkermes, Inc. (NASDAQ: ALKS) today announced positive preclinical results for its proprietary small molecule candidate, RDC-1036, which emerged from a library of novel opioid modulators. The data demonstrated RDC-1036 was effective in reversing opioid effects on gastrointestinal motility. Data also showed that oral administration of RDC-1036 had greater efficacy at a lower dose and for an extended period of time compared to an active comparator, methylnaltrexone. The data were presented at the 38th Annual Meeting of the Society for Neuroscience in Washington, D.C.

According to IMS Health, 200 million prescriptions were written for opioids in 2007 in the United States. Many studies indicate that a high percentage of patients receiving opioids are likely to experience side effects affecting gastrointestinal motility.

"While opioids are a common and effective treatment for managing chronic pain, the side effects of these medications can be debilitating and may diminish patient adherence to pain medication," stated Daniel Deaver, Ph.D., vice president, non-clinical development of Alkermes. "We are encouraged by these preclinical results as they suggest that the unique, oral formulation of RDC-1036 may enable the use of pain medications without inhibiting gastrointestinal motility."

The study results presented included efficacy and sustainability data of RDC-1036 compared to methylnaltrexone administered orally and parentally in a well-characterized rodent model of gut motility. Data showed that treatment with oral RDC-1036 blocked opioid-induced side effects for up to four hours at a dose three-fold lower than oral methylnaltrexone. Additionally, oral RDC-1036 had a faster onset of action compared to methylnaltrexone and maintained sustained efficacy for at least eight hours, compared to four hours with methylnatrexone. These data suggest oral RDC-1036 may be effective in reducing gastrointestinal side effects associated with opioid use.

"We are pleased to present these data on RDC-1036 as an example of our emerging proprietary pipeline," said Elliot Ehrich, M.D., chief medical officer of Alkermes. "These preclinical results are encouraging and suggest that we can successfully leverage our biological and chemical expertise to advance candidates from discovery to development."

About Alkermes

Alkermes, Inc., a biotechnology company committed to developing innovative medicines to improve patients' lives, manufactures RISPERDAL® CONSTA® for schizophrenia and developed and manufactures VIVITROL® 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.

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 therapeutic value of RDC-1036 and Alkermes' plans to continue development of RDC-1036. 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® is a registered trademark of Cephalon, Inc.; RISPERDAL® CONSTA® is a registered trademark of Janssen-Cilag group of companies.