Chiesi Secures $486M Agreement with Gossamer for Hypertension Drug

Chiesi Group, an Italian pharmaceutical company, has entered into a global collaboration and licensing agreement with Gossamer Bio, a biotech firm, to develop a treatment for pulmonary arterial hypertension (PAH) called seralutinib. This deal, potentially worth up to $486 million, focuses on advancing seralutinib, which has already shown promise in clinical trials.

Gossamer Bio will spearhead the global development of seralutinib for PAH and pulmonary hypertension associated with interstitial lung disease (PH-ILD). Seralutinib is a multi-targeted inhibitor, specifically targeting PDGFRα/β, CSF1R, and c-KIT, and is administered via an inhalable dry powder. Gossamer Bio will receive initial development funding of $160 million and could earn an additional $146 million pending regulatory milestones and $180 million through sales milestones.

Chiesi will handle the commercialization and sales of seralutinib in the U.S. outside of PAH and PH-ILD indications, while Gossamer Bio will focus on these indications within the U.S. Both companies will share commercial efforts equally in the U.S. Chiesi will obtain exclusive rights to market seralutinib outside the U.S. and will pay Gossamer Bio royalties based on net sales. The development expenses for the drug will be shared, with Gossamer Bio assuming the financial responsibilities for a Phase III trial in PAH patients. A global Phase III registrational study in PH-ILD is scheduled to begin in mid-2025.

Faheem Hasnain, CEO of Gossamer Bio, emphasized that this partnership allows for an expedited and enhanced investment in seralutinib's potential applications beyond PAH and PH-ILD, addressing unmet medical needs. Hasnain expressed excitement about moving directly into a Phase III trial for PH-ILD, a condition with limited treatment options that seralutinib is designed to target effectively.

Following its success in a Phase II study, Gossamer Bio launched a Phase III trial for seralutinib in PAH last year. The Phase II trial met its primary endpoint, showing a reduction in pulmonary vascular resistance at 24 weeks from baseline. However, it did not achieve statistical significance in the secondary endpoint of the six-minute walk distance, which remains a focal point in the ongoing Phase III study. Despite the mixed results, both Chiesi and Gossamer Bio are optimistic about the drug’s potential and the positive response from patients.

Giuseppe Accogli, CEO of Chiesi Group, highlighted the transformative potential of seralutinib for PAH and PH-ILD and expressed enthusiasm about the partnership with Gossamer Bio. Accogli believes that this cooperation will help bring this novel therapy to patients worldwide.

The development of seralutinib comes shortly after Merck's approval of Winrevair, the first FDA-approved activin signaling inhibitor for PAH. Merck acquired the rights to Winrevair through its $11.5 billion purchase of Acceleron Pharma in 2021.

Overall, the collaboration between Chiesi Group and Gossamer Bio represents a strategic effort to advance the treatment options for pulmonary hypertension, with seralutinib possibly emerging as a significant therapeutic breakthrough for patients suffering from PAH and PH-ILD.