Exhibit 99.1 PTC Therapeutics Provides Corporate Update and Reports First Quarter 2024 Financial Results – Strong revenue performance across product portfolio – – Submitted MAA for sepiapterin and BLA for Upstaza – – On target to achieve remaining 2024 clinical and regulatory milestones, including global submissions for sepiapterin – WARREN, N.J., April 25, 2024 – PTC Therapeutics, Inc., (NASDAQ: PTCT) today announced a corporate update and financial results for the first quarter ending March 31, 2024. “We ...