Gossamer Bio secures up to US$250M for seralutinib development

Gossamer Bio has entered into a private placement agreement to raise up to US$250 million to support the development and potential FDA approval of seralutinib. The investigational treatment is intended for pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD).

The financing is structured in stages linked to regulatory milestones. An initial closing is expected to generate approximately US$25 million. A second tranche of US$125 million is contingent upon the FDA accepting the company’s new drug application (NDA) for seralutinib in PAH. Additionally, investors may provide up to US$100 million through warrants exercisable upon FDA approval.

Gossamer Bio expects to submit the NDA by September 2026 and anticipates the net proceeds will fund operations through 2028. Separately, D. E. Shaw & Co. has disclosed a 6.0 percent stake in the company, representing over 29 million shares.