Selexipag for the treatment of pulmonary arterial hypertension.

The endothelin (ET), nitric oxide (NO) and prostacyclin (PGI2) pathways are involved in pulmonary arterial hypertension (PAH) pathogenesis. While ET and NO are targeted early in the disease process, limitations of current pharmacotherapies that target the PGI2 pathway (PGI2 or PGI2 analogues) result in them not being used or delayed. Selexipag is a novel oral, selective agonist of the PGI2 (IP) receptor. Activation of the IP receptor induces vasodilation in the pulmonary circulation and inhibits the proliferation of vascular smooth muscle cells, key factors in PAH pathogenesis. By combining oral dosing with improved receptor selectivity, selexipag may enable earlier combination therapy targeting the three-molecular pathways of PAH with anticipated improvements in daily- and long-term clinical function and outcome in PAH.