Objective:

This retrospective, observational analysis evaluated cenobamate retention in a nationally representative administrative claims database.

Background:

Real-world experience with cenobamate has yet to be reported in a nationally representative sample.

Design/Methods:

We utilized a sample of patients from HealthVerity Marketplace, which includes more than 150 US commercial, Medicare, and Medicaid payers, to identify a cohort of adults (age ≥18 years) with prevalent epilepsy and at least 1 script for cenobamate (initiated at dosages of 12.5-50 mg) or any of the branded ASMs (brivaracetam, eslicarbazepine, lacosamide, perampanel). Outcomes were blended for branded ASMs. Follow-up began May 2020 and extended until December 31, 2021, with only adjudicated medical and pharmacy claims from patients with complete enrollment history included. The index date for the analysis was Day 1 of cenobamate or branded ASM initiation. Patients had to have at least a year’s worth of follow-up before and after the index date for inclusion in the analysis. Using Kaplan-Meier methods, patients were followed  until an incident event occurred (cessation of cenobamate or branded ASM) or end of data collection.

Results:

Data were available from 1943 and 18,954 patients on cenobamate and branded ASMs, respectively, with 195 patients (mean age=38.2 years; % female=46.7%) and 4046 patients (mean age=42.4 years; % female=55.6%) meeting the inclusion/exclusion criteria. Median time to discontinuation was not reached in 12 months of follow-up for cenobamate and was 7.8 months for the branded ASMs. Retention at Months 3, 6, 9, and 12 was 72%, 62%, 58%, and 50%, respectively, for cenobamate, and 66%, 55%, 48%, and 40%, respectively, for branded ASMs (P=0.045). 

Conclusions:

Cenobamate was associated with significantly better retention vs 4 pooled branded ASMs in this analysis of real-world use. Unmeasured differences across the 2 groups that impact differential retention outcomes (eg, patient severity, drug load, and use of monotherapy) are potential limitations of this analysis.