This active molecular is a Epoprostenol receptor agonist which is an investigational drug candidate developed by Arena and intended for the treatment of vasospastic diseases, for an example, Pulmonary Arterial Hypertension . Ralinepag has the potential to mimic prostacyclin which elicits a potent vasodilation and inhibits platelet aggregation when binding to this receptor. In Jan 2015, Phase-II clinical trials in Pulmonary arterial hypertension in USA was on going. In Jul 2015, Phase-II clinical trials in Pulmonary arterial hypertension in Spain was on going. In Jul 2015, Arena initiated enrolment in a phase II extension trial for Pulmonary arterial hypertension in USA, Czech Republic, Hungary, Poland.