Abstract
Major limitations of pulmonary arterial hypertension (PAH) drug trials include the small number of enrolled patients, short term follow up (12-16 weeks), and lack of morbidity and mortality primary endpoints. The recently published SERAPHIN (Study with an Endothelin Receptor Antagonist in Pulmonary arterial Hypertension to Improve cliNical outcome) trial represents an important landmark in the history of clinical trials in PAH being the largest and longest clinical study conducted thus far in PAH patients with morbidity and mortality events as primary endpoint. SERAPHIN trial investigated whether long-term treatment with the new endothelin receptor antagonist macitentan would reduce the risk of mortality and morbidity in PAH patients.