Selexipag for the treatment of pulmonary arterial hypertension

Introduction: Targeted pulmonary vasoactive substances are the cornerstone of treatment in pulmonary arterial hypertension (PAH). Approved drugs act on various receptors and molecules within the pulmonary arteries, mainly causing pulmonary vasodilation and potentially reversing remodeling with consequent improvement of right ventricular function. A key role is attributed to the prostacyclin pathway and especially the prostacyclin receptor (IP). Selexipag is a recently developed, non-prostanoid, oral IP receptor agonist for the treatment of PAH which has been approved in countries/regions including the USA and Europe. Areas covered: We review the discovery and development of drugs targeting IP receptors in PAH and describe preclinical and phase I studies of selexipag. Furthermore, we review important phase II and III selexipag studies and place them into the clinical context of previously approved prostanoids. Expert opinion: Oral selexipag offers a promising therapeutic option within the class of available drugs targeting IP receptors. However, its role as first-line therapy based on its efficacy/side-effect profile in current studies is questionable. Most likely, selexipag will be used in combination with other PAHspecific oral drugs. The potential of selexipag to replace or postpone the use of inhaled or parenteral prostanoids needs to be investigated in future trials.