Comparative economic outcomes in patients with focal seizures initiating eslicarbazepine acetate versus brivaracetam as their first adjunctive ASD

Abstract

Aims: To study the association between initiation of first adjunctive therapy with eslicarbazepine acetate (ESL) vs. brivaracetam (BRV) on healthcare resource utilization (HCRU) and charges among patients with treated focal seizures (FS). Materials and methods: Symphony Health’s Integrated Dataverse (IDV) claims data (1 April 2015 to 30 June 2018) were used to identify two cohorts as first adjunctive therapy with ESL or BRV following a generic anti-seizure drug (ASD). The index date was the earliest claim for a new ESL or BRV prescription. Key inclusion criteria were only 1 generic ASD in the 12 months before the index date; ≥1 medical claim with an FS diagnosis. Unit of analysis was the 90-day person-time-block. Changes in HCRU and charges were assessed using a difference-in-differences framework. Both unadjusted and adjusted analyses were performed. The adjusted model utilized person-specific fixed effects and propensity score-based weighting to control for differences in baseline covariates. Bias-corrected bootstrap confidence intervals (CIs) were calculated for charge outcomes. Results: 208 and 137 patients initiated first adjunctive therapy with ESL (43.7 years, 51.9% female) or BRV (39.3 years, 51.8% female). Patients in the ESL cohort had numerically larger reductions in all-cause and FS-related inpatient hospitalizations and outpatient visits and FS-related emergency department visits. Compared to patients initiating BRV, patients treated with ESL had significantly larger reductions in total charges (−$3,446, CI: −$13,716, −$425), all-cause (−$3,166, CI: −$13,991, −$323) and FS-related (−$2,969, CI: −$21,547, −$842) medical charges, all-cause (−$3,397, CI: −$15,676, −$818) and FS-related (−$2,863, CI: −$19,707, −$787) outpatient charges, and non-ASD-related prescription charges (−$420, CI: −$1,058, −$78). Limitations: Claims may be missing, or miscoded; outcomes may be influenced by variables not accounted for in the analysis; only information on submitted charges was included. Conclusions: Among patients with FS, initiation of first adjunctive therapy with ESL was associated with significantly larger reductions in medical and non-ASD-related prescriptions charges compared to BRV.