Letter to the Community from PTC Therapeutics

Dear Duchenne Community,

On behalf of all of PTC, we want to thank all of you for supporting the advisory committee review of ataluren. As you know, the meeting was held last Thursday, Sept. 28th. We were pleased that we could share the scientific data from our placebo controlled trials, our long-term extension studies, and that the Duchenne community had a platform to share experiences and observations through both oral testimony and written comments. The passion, commitment and determination was clear to everyone that witnessed the meeting.

The meeting marked a significant milestone within the FDA review of ataluren as the agency considers their evaluation. We hope that the FDA will consider all the information heard at the Advisory Committee meeting, including the experiences that were shared as they complete their review. The target date for the FDA to complete their review (referred to as PDUFA date) is October 24, 2017 and we will continue to keep you updated as details are available to share.

Again, from the bottom of our hearts we thank you for your support and strong partnership with the Duchenne Community through our nearly 20-year journey.

Sincerely,

Stuart Peltz, Ph.D.

President and CEO, PTC Therapeutics, Inc.