Rationale: Cenobamate is an antiseizure medication (ASM) approved in the United States (XCOPRI®) and Europe (ONTOZRY®) as a treatment for adults with focal seizures. This retrospective observational analysis used data from a national claims database to compare epilepsy-specific inpatient stay (IP) rates and emergency room (ER) admission rates for patients diagnosed with focal epilepsy and adding cenobamate or one of seven other newer ASMs to their treatment regimen.
Methods: Patients with a diagnosis of focal epilepsy [ICD-10-CM G40.0*-G40.2*] taking at least one ASM between 1/1/2017 through 12/31/2021 were identified from the HealthVerity Marketplace Private Source 20 database. Patients were required to have ≥12 months of medical and pharmacy enrollment before their first line of therapy. New lines of therapy were defined as the dispensing of an ASM via a retail pharmacy after ≥30 days without exposure. Mixed-effect generalized Poisson regressions (with a log link function) estimated the association between ASM-specific therapy lines and proxy measures of seizure control (epilepsy-related IP days and ER admissions) among patients with a diagnosis of focal epilepsy. We compared therapy lines adding cenobamate with those adding brivaracetam, clobazam, eslicarbazepine, lacosamide, lamotrigine, levetiracetam, or perampanel.
Results: A total of 58,786 patients (55.7% female, mean [SD] age = 42.0 [16.2] years) were exposed to 84,301 lines of therapy. Intractable epilepsy was present in 62.8% (n=36,924) of patients, and 39.5% (n=23,238) had a history of status epilepticus. Overall therapy lines for ASMs ranged from 2069 for cenobamate (2062 unique patients) to 26,485 for lacosamide (25,889 unique patients). All new therapy lines included 10.4% (n=8670) first-line, 23.6% (n=19,878) second-line, and 66.1% (n=55,753) later-line therapies. Over 116,859.2 person years, ( >42.6 million total days of therapy), patients experienced 170.6 IP days and 41.0 ER admissions per 100 person-years; 25.4% (n=18,002) of patients also had at least one IP or ER admission within 90 days before therapy start. Compared with patients on cenobamate, all other 7 ASMs demonstrated higher IP day rates (all
P≤0.001) and higher ER admission rates (all
P≤0.001). Relative to cenobamate, adjusted mean increases in IP days ranged from 1.7 (lamotrigine) to 6.4 (lacosamide) per 100 patient-years (
Figure 1). Adjusted mean increases in ER admissions per patient year ranged from 2.0 (brivaracetam) to 8.8 (levetiracetam) per 100 patient-years.
Conclusions: As part of a retrospective claims-based analysis, cenobamate was associated with lower IP days and ER rates than seven leading ASMs for patients diagnosed with focal epilepsy. As this was a claims-based analysis, seizure frequency outcomes could not be assessed. Additional comparative research in unplanned healthcare utilization is needed to assess the benefit of ASMs in patients with epilepsy.
Funding: Funded by SK Life Science, Inc.