Inhaled Treprostinil Vs Iloprost: Comparison of Adherence, Persistence, and Health Care Resource Utilization in Patients with Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is associated with a substantial clinical and economic burden. Inhaled prostacyclins are a well-established part of pharmacotherapy for PAH. There are differences between inhaled therapies in the burden imposed by administration frequency. Simpler and less time-consuming inhaled PAH therapies may improve both adherence and persistence and potentially affect outcomes. To compare real-world health care resource use, costs, and treatment adherence and persistence in patients with PAH who initiated inhaled treprostinil or iloprost. Adult patients with 1 inpatient or 2 outpatient medical claims separated by at least 30 days with a diagnosis of PAH were identified using codes with a pharmacy claim for inhaled treprostinil or iloprost. Patients were required to be continuously enrolled in the health plan for 6 months prior to and 12 months after the index date. A proportion of days covered of 0.8 or more was considered adherent; persistence was no gap in therapy for at least 60 days. All-cause health care resource utilization and all-cause costs were assessed. 405 and 62 patients were included in the inhaled treprostinil and iloprost cohorts, respectively. Adherence (50.9% and 22.6%; < 0.0001) and persistence (6 months, 65.2% vs 35.5%; 12 months, 46.7% vs 16.1%; log-rank < 0.001) were significantly better with inhaled treprostinil. Post-index allcause inpatient admissions (39.3% vs 54.8%; = 0.02) and post-index emergency department (ED) utilization (36.3% vs 50.0%; = 0.04) were lower with inhaled treprostinil. Among patients who were persistent with therapy through 12 months, there was no significant difference between groups in mean (SD) all-cause total costs ($266,462 [137,324] vs $262,826 [112,452] for inhaled treprostinil vs iloprost, respectively; = 0.98). The results suggest that inhaled treprostinil is less burdensome, is associated with greater adherence and persistence, and may reduce all-cause hospitalizations and ED visits. This study was funded by the United Therapeutics Corporation to obtain data for this analysis and compose the manuscript. Dr Burger has served as clinical investigator in multicenter interventional trials sponsored by United Therapeutics but did not receive any direct compensation. Drs Wu and Morland and Mr Classi are employees of United Therapeutics Corporation and own stock/shares in the company.