Release Details

SOUTH PLAINFIELD, NJ – November 6, 2012 – PTC Therapeutics, Inc. (PTC) today announced the appointment of Geoffrey McDonough, M.D., to the company's Board of Directors. Dr. McDonough is the President and Chief Executive Officer of Swedish Orphan Biovitrum AB (Sobi), a leading European specialty pharmaceutical company developing therapies for patients with rare disorders and significant medical needs.

"We are honored to welcome Dr. McDonough to PTC's Board of Directors, his experience in orphan drug development and commercialization will be instrumental to PTC as we advance our pipeline and prepare for commercialization of ataluren in Duchenne/Becker muscular dystrophy and cystic fibrosis," said Stuart W. Peltz, Ph.D., Chief Executive Officer, PTC Therapeutics, Inc. "Dr. McDonough is renowned not only for his broad experience in genetic disorders but also for his passion for identifying solutions for patients with unmet medical needs."

Dr. McDonough has been with Sobi since August 2011. Prior to his appointment as CEO, he held several senior leadership positions at Genzyme Corporation from 2002 to 2011, most recently as President of Europe, Middle East and Africa (EMEA). While at Genzyme, Dr. McDonough also served as Senior Vice President and General Manager, Personalized Genetic Health, and Senior Vice President, Lysosomal Storage Disease (LSD) Therapeutics. Prior to joining Genzyme, Dr. McDonough was President and co-founder of Catalyst Medical Solutions, a developer of software for hospital revenue, medical documentation and compliance management, served as an adviser to RA Capital Management, and was a practicing internist and pediatrician. Dr. McDonough received his medical degree from Harvard Medical School, and a B.Sc. in biology and a B.A. in philosophy both summa cum laude from the University of North Carolina at Chapel Hill.

"PTC is a company committed to innovation in the service of patients with significant unmet medical needs," said Dr. McDonough. "I look forward to working with PTC to support the advancement of ataluren as well as the continued growth and development of its broad pipeline."

About PTC Therapeutics
PTC is a biopharmaceutical company focused on the discovery, development and commercialization of orally administered small-molecule drugs that target post-transcriptional control processes. Post-transcriptional control processes regulate the rate and timing of protein production and are of central importance to proper cellular function. PTC's internally discovered pipeline addresses multiple therapeutic areas, including rare genetic disorders, oncology and infectious diseases. PTC has developed proprietary technologies that it applies in its drug discovery activities and that have served as the basis for collaborations with leading biopharmaceutical companies. For more information, visit the company's website at www.ptcbio.com.

FOR MORE INFORMATION:

Jane Baj                                             Sheryl Seapy
PTC Therapeutics, Inc.                       Pure Communications
(908) 912-9167                                   (949) 608-0841
jbaj@ptcbio.com                                 sheryl@purecommunicationsinc.com