Singapore, Jun 3, 2009: Concert Pharmaceuticals and GlaxoSmithKline have decided to collaborate to develop and commercialize deuterium-containing medicines. The deal includes three of Concert's research and development programs; namely, CTP-518, a protease inhibitor for the treatment of HIV expected to enter phase I clinical trials in the second half of 2009, a preclinical compound for chronic renal disease, and a third research product in Concert's pipeline. Concert will also provide GSK with deuterium-modified versions of three GSK pipeline compounds for GSK to develop.

Under the terms of the agreement, Concert will receive $35 million in upfront payments, including a $16.7 million equity investment by GSK. Concert is eligible to receive milestones and tiered, double-digit royalties based on deuterium-containing products arising from the Concert pipeline programs. In addition, Concert is eligible to receive milestones as well as royalties on the sales of deuterium-containing products arising from the GSK pipeline compounds. Overall, Concert has the potential to receive in excess of $1 billion in total milestone and upfront payments from GSK spread across all programs.

For each Concert pipeline program, Concert will have responsibility for research and development activities through completion of pre-agreed clinical trials. After the completion of such clinical trials for each program, or earlier if it chooses, GSK may elect to obtain an exclusive, worldwide license to product candidates within the program. At such time, GSK will assume responsibility for development and commercialization. Concert will retain full rights to further develop and commercialize its product candidates in any program GSK chooses not to license.

"This agreement marks GSK's continued efforts to access the best science and technology platforms worldwide," said Patrick Vallance, Senior Vice-President Drug Discovery, GSK. "We believe Concert's approach to deuterium modification of medicines has broad potential to enhance certain drug properties and result in innovative new medicines."

"We are pleased to collaborate with GSK and to advance innovative small molecule drug candidates using our deuterium chemistry approach," said Roger Tung, Ph.D., President and Chief Executive Officer of Concert Pharmaceuticals. "This collaboration is a major step forward in our strategy to advance a broad pipeline of novel deuterium-modified therapeutics."