Gossamer Bio Hit With Class Action Lawsuit Alleging Concealed Placebo Risk in Failed Phase 3 Trial
Summary
A class action lawsuit has been filed against Gossamer Bio and an executive, alleging they concealed placebo risk in the Phase 3 PROSERA study for pulmonary arterial hypertension. This follows the company's February 23, 2026 announcement that the trial failed its primary endpoint, causing an 80% stock drop. The lawsuit adds significant legal and financial risk to Gossamer Bio, which is already facing a going concern warning, a Nasdaq delisting notice, and is undertaking a distressed debt exchange. Investors have until June 1, 2026, to seek to lead the class action.
At the time of this announcement, GOSS was trading at $0.22 on NASDAQ in the Life Sciences sector, with a market capitalization of approximately $51.1M. The 52-week trading range was $0.16 to $3.87. This news item was assessed with negative market sentiment and an importance score of 8 out of 10. Source: PR Newswire.