New horizons in pulmonary arterial hypertension therapies.

Pulmonary arterial hypertension (PAH) is a fatal disease associated with vasoconstriction and vascular remodelling. There are three well-known pathways that contribute to the pathogenesis of PAH: endothelin, nitric oxide and prostacyclin. Treatments targeting these pathways are well established in clinical practice, such as endothelin receptor antagonists, phosphodiesterase type-5 inhibitors and epoprostenol. New treatments have been developed with the aim of improving efficacy and ease of administration of therapies targeting these three established pathways, and several of these new treatments have recently undergone phase III investigation. Ongoing pre-clinical studies are also beginning to uncover other mechanisms that play a role in the complex pathobiology of PAH. These include genetic targets, transcription factors and signalling pathways. The discovery of new treatment targets may change the landscape of PAH therapy in the future. Herein, we present some of the promising future treatments and interesting new therapeutic targets.