The Law Offices of Frank R. Cruz reminds investors of the upcoming June 1, 2026 deadline to participate as a lead plaintiff in the securities fraud class action lawsuit filed on behalf of investors who acquired Gossamer Bio, Inc. (“Gossamer” or the “Company”) (NASDAQ: GOSS) securities between June 16, 2025 and February 20, 2026, inclusive (the “Class Period”).
IF YOU ARE AN INVESTOR WHO LOST MONEY ON GOSSAMER BIO, INC. (GOSS), CLICK HERE TO PARTICIPATE IN THE SECURITIES FRAUD LAWSUIT.
What Happened?
On February 23, 2026, Gossamer disclosed that results for its Phase 3 PROSERA study of seralutinib for the treatment of pulmonary arterial hypertension had failed to meet the primary endpoint, citing patients at Latin American sites performing particularly well on placebo due to enrollment of a heavily-treated lower-risk population.
On this news, Gossamer’s stock price fell $1.71, or 80.3%, to close at $0.42 per share on February 23, 2026, thereby injuring investors.
What Is The Lawsuit About?
The complaint filed in this class action alleges that throughout the Class Period, Defendants made materially false and/or misleading statements, as well as failed to disclose material adverse facts about the Company’s business, operations, and prospects. Specifically, Defendants failed to disclose to investors that: (1) patients at the Latin American sites were largely heavily-treated and lower risk and, ultimately, performed particularly well on the placebo, thus, Gossamer’s Phase 3 PROSERA study failed to meet the primary endpoint of improved six-minute walk distance at week 24; and (2) as a result, Defendants’ positive statements about the Company’s business, operations, and prospects were materially misleading and/or lacked a reasonable basis at all relevant times.
If you purchased or otherwise acquired Gossamer securities between June 16, 2025 and February 20, 2026, the deadline to seek appointment as the lead plaintiff in the securities fraud class action is June 1, 2026.
Contact Us To Participate or Learn More:
If you wish to learn more about this class action, or if you have any questions concerning this announcement or your rights or interests with respect to the pending class action lawsuit, please contact us:
Frank R. Cruz
The Law Offices of Frank R. Cruz,
2121 Avenue of the Stars, Suite 800,
Century City, California 90067
Email us at: info@frankcruzlaw.com
Call us at: 310-914-5007
Visit our website at www.frankcruzlaw.com
Follow us for updates on Twitter: twitter.com/FRC_LAW
If you inquire by email, please include your mailing address, telephone number, and number of shares purchased.
To be a member of the class action you need not take any action at this time; you may retain counsel of your choice or take no action and remain an absent member of the class action. This press release may be considered Attorney Advertising in some jurisdictions under the applicable law and ethical rules.
View source version on businesswire.com: https://www.businesswire.com/news/home/20260529451347/en/
Media gallery

