A review of prostaglandin analogs in the management of patients with pulmonary arterial hypertension.

Pulmonary arterial hypertension is a chronic, progressive disease characterized by elevation of pulmonary artery pressure and pulmonary vascular resistance that ultimately results in right ventricular failure and death. Multiple mechanisms are involved in the pathogenesis of pulmonary arterial hypertension, including prostacyclin, endothelin-1, and nitric oxide pathways amongst others. The first agent to be approved for the treatment of pulmonary arterial hypertension was synthetic prostacyclin (epoprostenol), followed by prostaglandin analogs (iloprost, treprostinil, and beraprost [Japan and Korea]), which act on prostaglandin receptors. This article reviews the physiology and pathophysiology of prostanoids, summarizes key clinical studies of prostaglandin analogs for the treatment of pulmonary arterial hypertension, and discusses important pharmacokinetic and pharmacodynamic distinctions between the various prostaglandin analogs. Different prostaglandin analogs have disparate binding affinities for the various prostaglandin receptors and different G-protein-coupled receptor interactions, which may result in varying clinical efficacy and safety depending on the target tissue. Differences in formulation, route of administration, effectiveness, and safety may all play a role in deciding which prostaglandin analog to prescribe for an individual patient. Head-to-head studies will be needed to confirm differences in efficacy and safety for the various prostaglandin analogs.