X0508 4 2025-12-01 0001070081 PTC THERAPEUTICS, INC. PTCT 0001808968 Klein Matthew B. C/O PTC THERAPEUTICS, INC. 500 WARREN CORPORATE CENTER DRIVE WARREN NJ 07059 true true false false CHIEF EXECUTIVE OFFICER 1 Common Stock 2025-12-01 4 A 0 15625 0 A 353392 D Common Stock 2025-12-02 4 S 0 3428 79.07 D 349964 D Represents the number of shares of the Issuer's common stock underlying restricted stock units ("RSUs") earned upon the vesting of performance-based restricted stock units ("PSUs") granted in December 2024. On December 1, 2025, the Issuer's board of directors certified the Issuer's achievement of a pre-established milestone set forth in the PSUs, which resulted in the reported RSUs being earned. Each earned RSU represents the contingent right to receive one share of the Issuer's common stock upon vesting. The earned RSUs immediately vested as to 7,812 shares on December 1, 2025 in connection with being earned and are scheduled to vest with respect to the remaining 7,813 shares on December 1, 2026. Represents shares automatically sold pursuant to an irrevocable sell to cover election entered into upon acceptance of the RSU grant to satisfy tax withholding obligations in connection with the vesting of the earned RSUs with respect to 7,812 shares on December 1, 2025. /s/ Avraham S. Alder, Attorney-in-Fact 2025-12-03