CoNCERT Pharmaceuticals Appoints Dr. Ronald W. Barrett to the Company’s Board of Directors

Concert Pharmaceuticals, Inc.

CoNCERT Pharmaceuticals Appoints Dr. Ronald W. Barrett to the Company’s Board of Directors

December 18, 2007

LEXINGTON, Mass., December 18, 2007 – CoNCERT Pharmaceuticals Inc., the first company dedicated to creating new medicines using precision modification chemistry with the naturally-occurring element deuterium, announced today the appointment of Ronald W. Barrett, Ph.D. to its Board of Directors. Dr. Barrett is chief executive officer, co-founder and director of XenoPort, Inc. (NASDAQ: XNPT), a biopharmaceutical company focused on developing a portfolio of internally discovered products candidates for the potential treatment of central nervous system disorders.

“Innovation is critical to success in the pharmaceutical industry, and CoNCERT’s deuterium chemistry platform has the potential to dramatically improve a broad range of validated drug molecules, while potentially reducing the time, expense and risk associated with traditional drug development,” stated Dr. Barrett. “I look forward to working with the entire CoNCERT team as they continue to develop their impressive pipeline of product candidates.”

Richard Aldrich, CoNCERT’s Chairman and former Chief Business Officer at Vertex, commented, “We are very pleased to welcome Dr. Barrett to the Board. His involvement speaks to the tremendous potential of CoNCERT’s approach to speed drug discovery and development in a risk-reduced manner and the progress the team has made since CoNCERT’s inception last year. We look forward to working closely with Dr. Barrett as we continue to execute on our strategy.”

“Dr. Barrett brings relevant operating experience to CoNCERT’s Board through his successful tenure at XenoPort, a clinical-stage company founded on the basis of improving the therapeutic benefits of existing drugs,” stated Roger Tung, Ph.D., President and Chief Executive Officer of CoNCERT. “Dr. Barrett’s guidance and perspective are particularly valuable now, as CoNCERT prepares for its first clinical study that is expected to begin in 2008 and continues to expand its rich pipeline of proprietary new chemical entities (NCEs).”

Prior to co-founding XenoPort in 1999, Dr. Barrett served as senior vice president of research at Affymax Research Institute (acquired by GlaxoSmithKline). Before Affymax, he was a molecular pharmacologist in the Neuroscience Group at Abbott Laboratories. Dr. Barrett is the inventor on more than 40 U.S. patents and has co-authored over 40 manuscripts in peer-reviewed journals. In 1996, he was co-recipient of the Newcomb-Cleveland Award for the year’s best manuscript in the publication Science. Dr. Barrett received his Ph.D. from Rutgers University and his B.S. from Bucknell University.

About CoNCERT

CoNCERT Pharmaceuticals is the first company dedicated to creating new medicines through a novel scientific approach utilizing the naturally-occurring element deuterium. CoNCERT applies its innovative precision chemistry platform to modify specific properties of validated drug molecules, yielding a rich pipeline of new chemical entities (NCEs). CoNCERT leverages decades of pharmaceutical experience to create drug candidates with potential for best-in-class efficacy and safety, while greatly reducing R&D risk, time and expense. The Company has over 100 patent applications for new drug candidates addressing a broad range of therapeutic areas, including hot flashes, fibrotic diseases, pain and infectious disease. CoNCERT expects to initiate its first clinical study in 2008. More information on CoNCERT can be found on the Company’s website at http://www.concertpharma.com.