Oral treprostinil in the treatment of pulmonary arterial hypertension.

INTRODUCTION: Pulmonary arterial hypertension (PAH) is a rare disease resulting in progressive remodeling of the pulmonary vasculature and eventual right ventricular failure. Despite the development of 13 therapies for PAH since 2000, the use of continuously infused prostanoids retains a special role. Infused medications present unique challenges, and the search for an efficacious oral prostanoid culminated in the FDA approval of oral treprostinil - a first in class oral prostanoid medication approved to treat pulmonary arterial hypertension (PAH). Areas covered: In this discussion, we review the pharmacologic properties of oral treprostinil, and discuss three original major registration studies that resulted in the approval and widespread use of the drug. We also review several post-approval analyses and transitional studies. We discuss administration issues including side effects, transitioning, cost, and comparative analysis with selexipag. Expert opinion: Though the prospects of harnessing the benefits of continuously infused prostanoid therapy in a pill form are tantalizing, the gap in efficacy between oral and infused treatment is substantial. Major side effects and exorbitant cost are further barriers to broad uptake. Competition from oral prostaglandin receptor agonist selexipag challenges the commercial success of oral treprostinil. The long-term viability of oral treprostinil rests largely on the outcome of the long-term event-driven study of the molecule added to background approved ERA or PDE5 inhibitor monotherapy.