d6b0ed5e_tus_Filed_Pursuant_to_Rule_424__2
[0] Directed share program [2] 
At our request, the underwriters have reserved up to 345,000 shares of our common stock offered by this prospectus for sale, at the initial public offering price, to our directors and officers and certain employees and other parties related to us. Shares purchased by our directors and officers will be subject to the 180-day lock-up restriction described in the "Underwriting" section of this prospectus. The number of shares of common stock available for sale to the general public will be reduced to the extent these individuals purchase such reserved shares. Any reserved shares that are not so purchased will be offered by the underwriters to the general public on the same basis as the other shares offered by this prospectus.
PTC Therapeutics - Prospectus Filed Pursuant to Rule 424
2