Dosing considerations in the use of intravenous prostanoids in pulmonary arterial hypertension: An experience-based review

BackgroundIntravenous (IV) prostanoid therapy remains arguably the most effective treatment of advanced pulmonary arterial hypertension (PAH) despite the introduction of newer molecules from different drug classes.MethodsLiterature regarding the properties, efficacy, safety, dosing, and cost of IV prostanoids was reviewed. In addition, a survey of physicians who treat PAH in the United States was conducted to assess IV prostanoid use in clinical practice.ResultsClinical studies have demonstrated that the 2 prostanoids available for IV administration in the United States, epoprostenol and treprostinil, improve exercise capacity, dyspnea, and cardiopulmonary hemodynamics in patients with PAH. Furthermore, epoprostenol has been shown to improve quality of life, functional class, and survival. The safety profiles of epoprostenol and IV treprostinil during short-term therapy appear comparable. Potential differences in the biochemical properties of these 2 drugs may have clinical implications. Whereas long-term data with subcutaneous treprostinil have been published, such data for IV treprostinil are not currently available. The physician survey revealed differences in the common maintenance doses used for both drugs, with IV treprostinil dosing approximately twice that of epoprostenol. These differences in dose have a direct bearing on the cost of therapy.ConclusionsThe unique properties of epoprostenol and treprostinil translate into clinical differences, which can influence the amount of drug used to achieve satisfactory patient improvement in the acute and long-term settings.