Release Details

SOUTH PLAINFIELD, NJ – August 5, 2013 – PTC Therapeutics, Inc. (NASDAQ: PTCT) today announced that the company will report financial results for the second quarter ended June 30, 2013 following the close of market on Monday, August 12, 2013. PTC management will host a conference call and webcast to discuss financial results and provide a corporate update on Monday, August 12, 2013 at 4:30 p.m. (ET).

The call can be accessed by dialing 877-303-9216 (domestic) or 973-935-8152 (international) five minutes prior to the start of the call and providing the passcode 24942756. A live, listen-only webcast of the conference call can be accessed on the investor relations section of the PTC website at http://ptct.client.shareholder.com/eventdetail.cfm?eventid=132871. A webcast replay of the call will be available approximately two hours after completion of the call and will be archived on the company's website for two weeks.

ABOUT PTC THERAPEUTICS, INC. PTC is biopharmaceutical company focused on the discovery and development of orally-administered, proprietary small molecule drugs that target post-transcriptional control processes. While PTC's discovery programs are directed at targets in multiple therapeutic areas, PTC is focusing particularly on the development and commercialization of treatments for orphan and ultra-orphan disorders. Post-transcriptional control processes regulate the rate and timing of protein production and are essential to proper cellular function. PTC's internally-discovered pipeline addresses multiple therapeutic areas, including neuromuscular disorders, oncology and infectious diseases. For more information on the company, please visit our website www.ptcbio.com.

FOR MORE INFORMATION PLEASE CONTACT: Jane Baj +1 (908) 912-9167 jbaj@ptcbio.com

FORWARD LOOKING STATEMENTS: Any statements in this press release about future expectations, plans and prospects for the Company, including statements containing the words "believes," "anticipates," "plans," "expects," and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: those related to the initiation and conduct of clinical trials, availability of data from clinical trials, expectations for regulatory approvals, our scientific approach and general development progress, the availability or commercial potential of our product candidates and other factors discussed in the "Risk Factors" section of the final prospectus for our initial public offering, which is on file with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the Company's views as of the date of this release. The Company anticipates that subsequent events and developments will cause the Company's views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing the Company's views as of any date subsequent to the date of this release.