PRESS RELEASE: Review on the Therapeutic Potential of Sirtuins for Diseases of Aging

Sirtris Pharmaceuticals and Sirtuin Academic Thought Leaders Publish Review on the Therapeutic Potential of Sirtuins for Diseases of Aging

CAMBRIDGE, Mass. -- Aug 16, 2007 - Sirtris Pharmaceuticals, a biopharmaceutical company focused on discovering and developing small molecule drugs to treat diseases of aging, announced today that Sirtris, together with leading sirtuin researchers David A Sinclair, Ph.D. and Leonard P. Guarente, Ph.D., published a review in the MIT Tech Review entitled "Developing Drugs to Treat Diseases of Aging."

The review highlights the discovery of sirtuins, a novel class of enzymes, and their role in the aging process. Additionally, the article discusses the drug development path of SIRT1 activators as potential treatments for a range of diseases of aging including metabolic disorders such as Type 2 Diabetes, mitochondrial disorders such as MELAS, neurological disorders, and cancer.

"This review summarizes the growing body of evidence regarding the substantial therapeutic potential of SIRT1 activators, such as SRT501, our proprietary formulation of resveratrol, and new chemical entities which are 1000 times more potent than resveratrol, to address a broad range of diseases of aging," said Christoph Westphal, M.D., Ph.D., Chief Executive Officer of Sirtris Pharmaceuticals, Inc.

David A. Sinclair, Ph.D. is a scientific co-founder, member of the Board of Directors of Sirtris Pharmaceuticals, Associate Professor of Pathology at Harvard Medical School, and Director of the Glenn Laboratories for the Biological Mechanisms of Aging. Leonard P. Guarente is the Novartis Professor of Biology at the Massachusetts Institute of Technology.

The article can be accessed at:

About Sirtris Pharmaceuticals

Sirtris Pharmaceuticals is a biopharmaceutical company focused on discovering and developing proprietary, orally available, small molecule drugs with the potential to treat diseases associated with aging, including metabolic diseases such as Type 2 Diabetes. Our drug candidates are designed to mimic certain beneficial health effects of calorie restriction, without requiring a change in eating habits, by activation of sirtuins, a recently discovered class of enzymes that control the aging process. The company's headquarters are in Cambridge, Massachusetts.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, the potential therapeutic effects of SIRT1 activators for multiple neurodegenerative diseases and other types of disorders, the progress and results of pre-clinical studies of SIRT1 activators, and the potential of sirtuin modulators to receive regulatory approval. These forward-looking statements about future expectations, plans and prospects of Sirtris Pharmaceuticals involve significant risks, uncertainties and assumptions, including risks related to the lack of results that would provide a basis for predicting whether any of the Company's product candidates will be safe or effective, or receive regulatory approval, the possibility that results of pre-clinical studies are not necessarily predictive of clinical trial results, the Company's potential inability to initiate and complete pre-clinical studies and clinical trials for its product candidates, the fact that none of the Company's product candidates has received regulatory approvals, the potential inability of the Company to gain market acceptance of the Company's product candidates, and those other risks factors that can be found in the Company's filings with the Securities and Exchange Commission. Actual results may differ materially from those Sirtris Pharmaceuticals contemplated by these forward-looking statements. Sirtris Pharmaceuticals does not undertake to update any of these forward-looking statements to reflect a change in its views or events or circumstances that occur after the date of this release.