Exhibit 99.1 PTC Therapeutics Provides Corporate Update and Reports First Quarter 2025 Financial Results – Strong revenue performance of 190million––PositiveCHMPopinionforSephience™(sepiapterin)receivedinApril2025,NDAreviewremainsontrackforJuly29,2025PDUFAdate––GlobalSephiencelaunchactivitiesprogressingwell––Strongcashpositionofover2.0 billion as of March 31, 2025 – WARREN, N.J., May 6, 2025 – PTC Therapeutics, Inc., (NASDAQ: PTCT) today announced a corporate update ...