Newly Diagnosed PAH Patients at Risk of More Rapid Disease Progression

People newly diagnosed with pulmonary arterial hypertension (PAH) are at greater risk of disease progression than PAH patients sick for more than six months, a finding that highlights the importance of early treatment, researchers reported. Their study, “Incident and prevalent cohorts with pulmonary arterial hypertension: insight from SERAPHIN“, was published in the European Respiratory Journal.

The PAH patients investigated were enrolled in the SERAPHIN clinical trial, a study exploring changes in clinical outcomes of treatment with the endothelin receptor antagonist macitentan (Opsumit). Patients were grouped into those presenting new cases, with a diagnosis of six months or less before study enrollment, and those with prevalent cases, diagnosed more than six months before enrollment. In total, data was collected from 110 newly diagnosed and 157 long-term PAH patients.

Researchers, led by Gérald Simonneau at the Assistance Publique–Hôpitaux de Paris in France, estimated morbidity and mortality risks, as well as PAH-related death or hospitalization, in patient cohorts.

Among patients receiving placebo, the risk of both morbidity/mortality and PAH-related death/hospitalization was found to be higher at month 12 in new cases, compared to those who had been sick for a longer period of time. There was no difference in all-cause death rates between the groups.

Macitentan treatment reduced the risk of morbidity and mortality, as well as PAH-related death or hospitalization, in both groups of patients (new cases and prevalent cases) compared to placebo.

A more detailed analysis of disease progression events revealed that new cases had a higher risk for disease progression compared to long-term patients, but not a higher risk of death. Macitentan delayed disease progression in both incident and prevalent PAH patients.

The data confirmed earlier reports showing that patients who are newly diagnosed with PAH have a worse prognosis than long-term patients, but this is the first time these differences were investigated in a randomized controlled trial setting. The study was a multicenter international effort, and the authors noted that outcomes for both newly diagnosed and long-term patients differed among countries with good access to PAH treatment and those with limited access, stating that this difference should be taken into account when designing future clinical trials.

This study underscored the importance of initiating treatment as soon as PAH is diagnosed. The study also showed that macitentan is an effective first-line treatment, able to delay disease progression in both newly diagnosed and long-term PAH patients.