HEALTH OUTCOMES AND COSTS ASSOCIATED WITH ORAL TREPROSTINIL AND SELEXIPAG ONE YEAR INTO TREATMENT: A UNITED STATES CLAIMS DATABASE ANALYSIS IN PATIENTS WITH PULMONARY ARTERIAL HYPERTENSION

TOPIC: Pulmonary Vascular Disease TYPE: Original Investigations PURPOSE: Previous comparisons of oral treprostinil (TRE) and selexipag (SLX) using real-world data have been limited to short duration follow-up periods or have used models to estimate healthcare costs. This analysis aims to characterize various outcomes and direct healthcare costs for pulmonary arterial hypertension (PAH) patients being treated with TRE or SLX 1-year into treatment. METHODS: A retrospective analysis was completed using the IBM® MarketScan® Research Databases from January 2014 to June 2019. Patients were required to have a pulmonary hypertension inpatient or outpatient medical claim identified by International Classification of Disease Codes (ICD-9-CM: 416.0, 416.8, 416.9; ICD-10-CM: I27.0, I27.20, I27.21, I27.29, I27.81, I27.83, I27.89, I27.9) plus a prescription claim for TRE or SLX. The index date was defined as the day of the first claim for TRE or SLX. Patients were ≥18 years old and required to have a PH medical claim in the 6-month pre-index, continuous health insurance enrollment 6 months pre-index and 12 months post-index. Adherence was defined as having a medication possession ratio (MPR) ≥80% and persistence was defined by continuous therapy in the 1-year follow-up period without a medication gap of ≥60 days. RESULTS: 120 patients in the TRE cohort and 155 patients in the SLX cohort met inclusion criteria. Patients were of similar age (TRE: mean [SD] = 57.0 [16.1] vs. SLX: 57.2 [13.5]), similar sex (TRE: 70% female vs. SLX: 77.4%) and had a similar Charlson Comorbidity Index (CCI) score (TRE: mean [SD] 3.5 [2.6] vs. SLX: 3.1 [2.0]). Concomitant PAH therapies received during the pre-index period were generally similar between cohorts, however, more patients on TRE compared to SLX (11.7% vs. 2.6%, p=0.003) transitioned from parenteral PAH treatment. In the 1-year following treatment, adherence and persistence were comparable: adherence was 83% for TRE and 81% for SLX (p=0.567) and persistence was 53% for TRE and 59% for SLX (p=0.373). Among the patients persistent on therapy at 1-year, median (IQR) annual pharmacy costs were $232,071 ($211,039-$256,402) for SLX compared with $107,511 ($45,647-$186,622) for TRE (p<0.01) representing 116% higher median annual pharmacy costs for SLX. A similar proportion within each group switched to parenteral prostacyclin therapy (TRE: 6.7% vs SLX: 5.2%, p=0.794) or inhaled prostacyclin therapy (TRE: 3.3% vs SLX: 3.2%, p=1.0) in the 1-year follow-up period. After adjusting for baseline differences between cohorts, total mean PAH-related healthcare costs (pharmacy + medical) in the 1-year follow-up period were $350,782 ($307,873-$394,849) for SLX compared to $229,564 ($198,791-$264,944) for TRE (p<0.05). CONCLUSIONS: Real-world claims data show similar utilization and outcomes for TRE and SLX in patients with PAH with notable differences in costs in the 1-year following treatment initiation. CLINICAL IMPLICATIONS: Cost differences between TRE and SLX should be considered when selecting oral prostacyclin therapies given the broader economic impact on the U.S. healthcare system as well as potential costs specific to health insurers, pharmacy-benefit managers, employers, and patients. DISCLOSURES: Employee relationship with United Therapeutics Please note: >$100000 by Peter Classi, source=Web Response, value=Salary Consultant relationship with United Therapeutics Please note: 2020-current Added 04/27/2021 by Bonnie Dean, source=Web Response, value=Grant/Research Support Employee relationship with United Therapeutics Please note: 2017 to Present Added 04/27/2021 by Alex DeRuiter, source=Web Response, value=Salary Employee relationship with Xcenda, LLC Please note: 01/04/2020 Added 04/30/2021 by Henry Lee, source=Web Response, value=Salary Employee relationship with United Therapeutics Corporation Please note: >$100000 by Kellie Morland, source=Web Response, value=Salary Employee relationship with Xcenda LLC Please note: Jan 1, 2020 Added 04/27/2021 by Dana Stafkey-Mailey, source=Web Response, value=UT provided Xcenda Fin Support Employee relationship with United Therapeutics Corporation Please note: 11 Months Added 04/27/2021 by Benjamin Wu, source=Web Response, value=Salary