Item 2.02. Results of Operations and Financial Condition. On May 7, 2026, PTC Therapeutics, Inc. (the “ Company”) announced its financial results for the quarter ended March 31, 2026. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (this "Report") and is incorporated by reference into this Item 2.02.

Item 7.01. Regulation FD Disclosure. The Company will host a conference call on May 7, 2026 at 4:30 p. m. eastern time, as previously announced. During this call the Company expects to review financial results for the quarter ended March 31, 2026, as well as other corporate highlights and updates. Instructions on how to access the conference call are included in the press release furnished as Exhibit 99.1 hereto. The information in this Report (including Items 2.02 and 7.01 and Exhibit 99.1) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “ Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing. All website addresses given in this Report or incorporated herein by reference are for information only and are not intended to be an active link or to incorporate any website information into this Report.

Item 9.01. Financial Statements and Exhibits. (d) Exhibits Exhibit No. Description 99.1 Press Release, dated May 7, 2026 issued by PTC Therapeutics, Inc. ────────────────────────────────────────────────────────────────────────────────────────────────── 104 The cover page from this Current Report on Form 8-K, formatted in Inline XBRL Signature Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this Report to be signed on its behalf by the undersigned hereunto duly authorized. PTC Therapeutics, Inc. Date: May 7, 2026 By: /s/ Pierre Gravier Name: Pierre Gravier Title: Chief Financial Officer