Gossamer Bio Collaborates With Italian Drugmaker Chiesi To Advance Lung Health Solutions Worldwide

Gossamer Bio Inc GOSS and Italy-based Chiesi Farmaceutici S.p.A, have entered a global collaboration and license agreement to develop and commercialize seralutinib.

This global collaboration combines the strengths of both Chiesi and Gossamer to support ongoing work in pulmonary arterial hypertension (PAH) and to accelerate the development of pulmonary hypertension associated with interstitial lung disease (PH-ILD).

“Seralutinib is a potential paradigm-shifting therapy in PAH and PH-ILD, and we could not be more excited to partner with Gossamer to develop and bring this therapy to patients worldwide,” said Giuseppe Accogli, Group CEO of Chiesi. 

PAH is believed to affect approximately 30,000 to 50,000 people in the US, with a similar prevalence in Europe. While many approved PAH treatments are available, most are primarily vasodilators and do not impact the progressive course of the disease. Median 5-year overall survival rate for patients with PAH is approximately 57%. 

The company estimates that PH-ILD affects approximately 60,000-100,000 patients in the US. 

Patients with PH-ILD in the US have access to only one approved therapy, while no therapies to treat PH-ILD are approved outside of the US. Median 5-year overall survival rate for patients with PH-ILD is approximately 23%.

Seralutinib is an inhaled PDGFRα/β, CSF1R, and c-KIT inhibitor designed to be delivered via dry powder inhaler for the potential treatment of pulmonary hypertension.

 Following the readout of the Phase 2 TORREY Study in patients with PAH, Gossamer initiated the Phase 3 PROSERA Study in 2023. 

Gossamer and Chiesi plan to initiate a global Phase 3 registrational study in PH-ILD in mid-2025 and to evaluate seralutinib in additional indications.

Under the terms of the agreement, Gossamer will continue to lead the global development of erlotinib in PAH and PH-ILD, and the companies will evenly split development costs, except with respect to the PROSERA Study, for which Gossamer will remain financially responsible. 

In the U.S., the companies will evenly share commercial profits and losses. 

Gossamer will lead commercialization and book sales for PAH and PH-ILD in the US, with both companies contributing 50% of commercial efforts. 

Chiesi will lead US commercialization in additional indications. Chiesi will have the exclusive right to commercialize seralutinib outside of the US and will pay Gossamer an escalating mid-to-high teens royalty on net sales. 

Chiesi will pay Gossamer $160 million as a development reimbursement. Additionally, Gossamer will be eligible to receive up to $146 million in regulatory milestones and $180 million in sales milestones.

Price Action: GOSS shares are up 1.26% at $0.74 at last check Monday.