Sotatercept (brand name Winrevair) is a first-in-class medication approved for the treatment of pulmonary arterial hypertension.
It is given by subcutaneous injection and is used to increase exercise capacity, improve functional class, and reduce the risk of clinical worsening events.
It is an activin signaling inhibitor, specifically a recombinant fusion protein combining the extracellular domain of the activin type IIA receptor with an IgG1 Fc domain.
A first in class activin signaling inhibitor.
It is a therapeutic  alternative to vasodilators in the treatment of pulmonary arterial hypertension by binding pro proliferative members of the transforming growth factor to beta superfamily, targeting pulmonary vascular remodeling.
It acts as a ligand trap for activin-class ligands, rebalancing pro-proliferative and anti-proliferative signaling pathways involved in PAH, which can reduce abnormal blood vessel growth and improve blood flow in the lungs.
It has been shown to lower the risk of death, lung transplantation, and hospitalization for worsening PAH in high-risk patients, even when added to maximum background therapy.
Sotatercept improves exercise capacity and can partially reverse structural changes in the pulmonary arteries.
Common side effects: headache, nosebleeds, rash, spider veins, diarrhea, dizziness, and skin redness.
It can increase hemoglobin and decrease the platelet count.
It may impair fertility and cause fetal harm if used during pregnancy.