Lung Association, Merck Partner to Raise Awareness of PAH

The American Lung Association (ALA) is hoping to lower rates of undiagnosed pulmonary arterial hypertension (PAH) through a new educational campaign.

The new campaign is a response to the persistent problem of delayed diagnosis among people with PAH, but it also reflects growing attention to the disease by drug developers and scientific investigators.

Left untreated, PAH can be deadly. However, therapy can significantly improve symptoms and extend patient survival. The most recent therapeutic advancement was the FDA’s approval of Winrevair (sotatercept) earlier this year. Merck & Co.’s drug is an activin signaling inhibitor therapy, the first of its kind.

The development of Winrevair was part of a wave of new research clarifying the pathogenesis of the disease and identifying potential new drug targets. Yet, that wave of scientific interest in the disease has not necessarily translated into greater public awareness of the disease.

Harold Wimmer, M.S., the ALA’s president and CEO, said the goal of the campaign is to improve the lives of people with the disease by helping them get earlier access to therapy.

“Through this campaign, we hope to improve awareness and understanding of PAH, promote early diagnosis, and provide valuable resources for patients and caregivers,” he said, in a press release.

The campaign is being supported by Merck, which reported sales of $149 million for Winrevair as of the third quarter of 2024. The company noted that Winrevair was also recently approved in Europe, and has already launched in Germany. Merck said it expects to obtain reimbursement for the drug in most of the other major European markets in the second half of next year.

The ALA estimates that between 500 and 1,000 people are diagnosed with PAH each year in the United States, though it is unknown how many people have undiagnosed cases. Historically, late diagnosis of PAH has been a significant challenge.

An Australian study from 2013 found that the mean time from symptom onset to diagnosis was 47 months among patients with idiopathic PAH. On average, patients reported seeing their primary care doctor 5.3 times and a specialist 3 times before being seen at a PAH center.

A U.S.-based study published in 2011 found that 1 in 5 adult patients in a PAH registry had reported symptoms for more than 2 years before their disease was correctly diagnosed as PAH. The authors of that study found that younger age and a history of common respiratory disorders were associated with delays in PAH diagnosis.

In the early stages of the disease, symptoms may be fewer or non-apparent to patients. When the disease progresses, symptoms of the disease can include shortness of breath, fatigue, swelling of the feet and legs, dizziness, chest pain, and heart palpitations. The ALA noted that asthma and congestive heart failure both have similar symptoms to PAH, which can lead to misdiagnosis in some patients.