Merck's (MRK.US) "first-in-class" therapy Winrevair met the primary endpoint in its Phase 3 trial
1min read Merck & Co., Inc. (MRK.US) today announced that its "first-in-class" therapy Winrevair (sotatercept) has met the primary endpoint in the Phase 3 ZENITH trial in an interim analysis. Based on this positive result, the trial will be terminated early, allowing all patients with pulmonary arterial hypertension (PAH) to have the opportunity to receive Winrevair. It is worth noting that this therapy was ranked as one of the potential blockbuster therapies expected to be approved in 2024 by industry media Evaluate.
PAH is a rare progressive disease that occurs when the small arteries in the lungs become thickened and narrowed, causing increased pressure in these arteries and putting pressure on the heart. The development of PAH involves three related processes, including inflammation, cell proliferation, and fibrosis, which play a key role in the thickening, narrowing, and stiffening of the small pulmonary arteries, which is often referred to as "vascular remodeling". Currently approved PAH therapies are mainly vasodilators that open up the vessels, but these treatments cannot reverse the vascular remodeling caused by inflammation, proliferation, and fibrosis.
Winrevair is a "first-in-class" ActRIIA fusion protein. It consists of the extracellular domain of ActRIIA that has been modified to bind to the Fc region of an antibody. It can block the binding of activin to its cell surface receptors, thereby reducing the signaling mediated by activin. In preclinical studies, it can reverse the remodeling of the pulmonary arterial wall and right ventricle. Winrevair is a key therapy that Merck acquired from Acceleron Pharma in 2021 for approximately $11.5 billion. It was approved by the US FDA in March this year.