"We are writing to let you know that Shire and Acceleron have decided to discontinue development of ACE-031 for Duchenne muscular dystrophy. As you may know, ACE-031 clinical trials have been on hold since February 2011. Since then, we have performed a number of additional non-clinical and toxicology studies, but unfortunately the findings from these studies do not support further development.

Thank you very much for your contributions to or interest in the ACE-031 program. We are deeply disappointed that we were not able to bring ACE-031 forward for the treatment of DMD patients. Each company remains committed to the development of novel therapies for DMD and other rare diseases."

Lawrence Charnas, MD, PhD Kenneth M. Attie, MD
Director & Head of Discovery Medicine VP, Medical Research
Shire Human Genetics Therapies Acceleron Pharm, Inc