ATLANTA, GA – – (Globe Newswire – April 1, 2026) – – A shareholder class action lawsuit has been filed against Gossamer Bio, Inc. (“Gossamer Bio” or the “Company”) (NASDAQ: GOSS). The lawsuit alleges that Defendants issued false and misleading statements and/or failed to disclose material adverse facts regarding Gossamer Bio’s study design for its Phase 3 PROSERA study, particularly with respect to controlling for the placebo response at the Latin American testing sites.

If you purchased Gossamer Bio shares between June 16, 2025 and February 20, 2026, and experienced a significant loss on that investment, you are encouraged to discuss your legal rights by contacting Corey D. Holzer, Esq. at cholzer@holzerlaw.com, by toll-free telephone at (888) 508-6832, or by visiting the firm’s website at www.holzerlaw.com/case/gossamer-bio/ for more information.

The deadline to ask the court to be appointed lead plaintiff in the case is June 1, 2026.