CAMBRIDGE, Mass.--(BUSINESS WIRE)--Sirtris Pharmaceuticals, Inc. (NASDAQ: SIRT), a biopharmaceutical company focused on discovering and developing small molecule drugs to treat diseases of aging such as Type 2 Diabetes, announced today that Leonard P. Guarente, PhD, Novartis Professor of Biology at the Massachusetts Institute of Technology, has signed a new, exclusive consulting agreement with Sirtris Pharmaceuticals. Dr. Guarente first joined Sirtris’ Scientific Advisory Board as Co-Chair in November 2007.