REGN EQUITY ACTION REMINDER: Faruqi & Faruqi, LLP Reminds Regeneron Investors of Securities Class Action Lawsuit Deadline on September 14, 2026

If you purchased or acquired securities in Regeneron between August 1, 2025 and May 15, 2026 and would like to discuss your legal rights, call Faruqi & Faruqi partner Josh Wilson directly at 877-247-4292 or 212-983-9330 (Ext. 1310) . [You may also click here for additional information] New York, New York--(Newsfile Corp. - August 31, 2026) - Faruqi & Faruqi, LLP , a leading national securities law firm, is investigating potential claims against Regeneron Pharmaceuticals, Inc. ("Regeneron" or the "Company") (NASDAQ: REGN) and reminds investors of the September 14, 2026 deadline to seek the role of lead plaintiff in a federal securities class action that has been filed against the Company. Faruqi & Faruqi is a leading national securities law firm with offices in New York, Pennsylvania, California and Georgia. The firm has recovered hundreds of millions of dollars for investors since its founding in 1995. See www.faruqilaw.com . As detailed below, the complaint alleges that the Company and its executives violated federal securities laws by making false and/or misleading statements and/or failing to disclose the true state of Regeneron's Phase III Fianlimab-Libtayo Study; notably, that its preliminary statistical assumptions were fundamentally flawed, that the active treatment arm was failing to achieve meaningful clinical differentiation over standard therapies, and that the trial would ultimately fail to reach statistical significance on its primary endpoint even without overperformance of the control arm. On April 29, 2026, Defendants disclosed that the Phase III Fianlimab-Libtayo Study had been altered, expanding the number of patients in the study eligible for "analysis of progression-free survival." On this news, Regeneron's stock price fell $45.41, or approximately 6.2%, to close at $686.36 per share on April 29, 2026. On May 15, 2026, Regeneron issued a press release announcing that the "Phase 3 Trial of Fianlimab . . . did not reach statistical significance for the primary endpoint of improvement in progression-free survival (PFS)." On this news, Regeneron's stock price fell $68.57, or approximately 9.8%, to close at $629.68 per share on May 18, 2026. The court-appointed lead plaintiff is the investor with the largest financial interest in the relief sought by the class who is adequate and typical of class members who directs and oversees the litigation on behalf of the putative class. Any member of the putative class may move the Court to serve as lead plaintiff through counsel of their choice, or may choose to do nothing and remain an absent class member. Your ability to share in any recovery is not affected by the decision to serve as a lead plaintiff or not. Faruqi & Faruqi, LLP also encourages anyone with information regarding Regeneron's conduct to contact the firm, including whistleblowers, former employees, shareholders and others. To learn more about the Regeneron class action, go to www.faruqilaw.com/[REGN](/en/us/REGN) or call Faruqi & Faruqi partner Josh Wilson directly at 877-247-4292 or 212-983-9330 (Ext. 1310) . Follow us for updates on LinkedIn , on X , or on Facebook . Frequently Asked Questions (FAQ) for Investors Regarding the Regeneron Securities Class Action Lawsuit: What is the Regeneron securities fraud lawsuit about? Faruqi & Faruqi, LLP has filed a securities class action lawsuit against Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) on behalf of investors who purchased Regeneron securities during the Class Period. The lawsuit alleges that Regeneron and certain of its officers made materially false and misleading statements regarding the Phase III Fianlimab-Libtayo clinical study. Specifically, the complaint alleges that defendants concealed that the study's preliminary statistical assumptions were fundamentally f...