Sotatercept was recently approved by the Food and Drug Administration (FDA) to treat adults with pulmonary arterial hypertension (PAH) after completing a Phase 3 clinical trial at Norton Pulmonary Specialists and other leading pulmonary hypertension centers.

Sotatercept, sold under the brand name Winrevair, is a new class of therapy for pulmonary arterial hypertension. It has been shown to increase exercise capacity, reduce symptoms that affect day-to-day activities and lower the risk of a PAH clinical worsening event.

Sotatercept FDA approval came in March after the regulator designated it as a “breakthrough” therapy potentially superior to current treatments for a life-threatening condition. The designation qualified the drug for an expedited review process.

“There’s no cure for pulmonary arterial hypertension, which is why new and better therapies like sotatercept are so important,” said John W. McConnell, M.D., medical director of Norton Healthcare’s pulmonary hypertension program and the local principal investigator in the clinical trial, NCT04576988. Dr. McConnell is a pulmonologist with Norton Pulmonary Specialists, the only practice in Kentucky or Southern Indiana to participate in the study. It continues to conduct clinical trials with sotatercept and other PAH treatments.

PAH is A rare disease that is progressive and ultimately life-threatening. It is characterized by narrowing or obstruction in the pulmonary arteries and significant strain on the right ventricle.

Pulmonary arterial hypertension results from the excessive growth and dysfunction of cells that line the arteries in the lungs, causing them to thicken and narrow. As an activin-signaling inhibitor, sotatercept helps regulate vascular cell proliferation and may allow the pulmonary artery and smaller arteries to revert to a healthier structure. It’s the first drug to do this.

“PAH remains a debilitating disease with high morbidity and mortality,” Eliav Barr, M.D., senior vice president, head of global clinical development and chief medical officer, Merck Research Laboratories, said in announcing the FDA approval. Merck purchased Acceleron Pharma in 2021 as it was conducting Phase 3 trials.

Conventional treatment has focused on restoring balance among nitric oxide, endothelin and prostacyclin, according to the American Lung Association.

PAH patients prescribed sotatercept will receive an injection of the drug every three weeks while continuing the conventional background PAH therapy such as epoprostenol (prostacyclin) infusions and diuretics. Patients will need to have their hemoglobin checked before the first five doses and can administer the subcutaneous injections themselves.

Even with insurance, some pulmonary arterial hypertension patients need help with the copay, according to Dr. McConnell. Nurses at Norton Pulmonary Specialists are available to help patients with the process of signing up for the drug once it’s prescribed and applying to sources of copay assistance.

Pulmonary hypertension affects an estimated 40,000 people in the United States. As many as half of them may be eligible for sotatercept.

Conventional treatment has focused on PAH background therapy to address pulmonary vascular resistance and help reduce strain on the heart and the risk of heart failure.

Pulmonary hypertension also affects quality of life. Many PAH patients need a continuous infusion therapy administered by a pump they must carry with them at all times. Supplemental oxygen is also required as the disease progresses.

The Phase 3 clinical trial was randomized, double-blind and placebo-controlled. Volunteers were symptomatic and on background PAH therapy. Trial results were published in the New England Journal of Medicine.

The 323 patients in the trial were roughly split between receiving sotatercept and a placebo. The study examined 10 end points and showed improvement in nine of the 10 end points, including the primary metric of six-minute walking range.

Participants given sotatercept were able to walk a median of 34.4 meters farther at the end of the 24-week study. Those given the placebo were able to walk 1 meter farther.

The other end points, except one, improved significantly with sotatercept compared with the placebo. They included:

• A decline in pulmonary vascular resistance with sotatercept compared with an increase with the placebo
• Lower levels of NT-proBNP, a protein the heart creates during heart failure
• In a third of the patients given sotatercept, an improvement in their World Health Organization PAH functional class, compared with 14% who were given a placebo

Only a measure of cognitive and emotional impacts did not improve and was unchanged for both groups.

Current pulmonary arterial hypertension clinical trials at Norton Pulmonary Specialists