Inhaled treprostinil vs iloprost: Comparison of adherence, persistence, and health care resource utilization in patients with pulmonary arterial hypertension

BACKGROUND: 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. OBJECTIVE: To compare real-world health care resource use, costs, and treatment adherence and persistence in patients with PAH who initiated inhaled treprostinil or iloprost. METHODS: Adult patients with 1 inpatient or 2 outpatient medical claims separated by at least 30 days with a diagnosis of PAH were identified using International Classification of Diseases, Ninth Revision or Tenth Revision, Clinical Modification 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. RESULTS: 405 and 62 patients were included in the inhaled treprostinil and iloprost cohorts, respectively. Adherence (50.9% and 22.6%; P< 0.0001) and persistence (6 months, 65.2% vs 35.5%; 12 months, 46.7% vs 16.1%; log-rank P<0.001) were significantly better with inhaled treprostinil. Post-index all-cause inpatient admissions (39.3% vs 54.8%; P=0.02) and post-index emergency department (ED) utilization (36.3% vs 50.0%; P=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; P=0.98). CONCLUSIONS: 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.