Objective:

Background:

Cenobamate is an antiseizure medication (ASM) approved in the US for the treatment of adults with focal seizures.

Design/Methods:

Patients with epilepsy (ICD-10-CM G40*) taking ≥2 prescription fills of cenobamate monotherapy between 5/1/2020-12/31/2022 were identified retrospectively from the HealthVerity Marketplace Private Source 20 database. Patients had to have ≥180 days of pharmacy/medical enrollment before and after first observed line of therapy (LOT), defined as dispensing of an ASM after ≥30 days without a previous fill. LOT not overlapping with another ASM >30 days after initiation was considered monotherapy. Epilepsy-related inpatient days and emergency room (ER) visits were assessed. 

Results:

299 patients (64.9% female, mean age=39.3 years; mean previous LOT=3) were included. Focal epilepsy was diagnosed in 72.9% (n=218) of patients; 69.9% (n=209) had a history of intractable seizures. Average line duration was 620.6 days during previous ASM LOT and 375.6 days during cenobamate monotherapy, including titration. Among 244 patients who switched to cenobamate monotherapy, the most common previous ASMs included lacosamide (n=35), lamotrigine (n=26), and gabapentin (n=24). During follow-up, 74 patients received add-on therapy, and 63 patients switched to another ASM. During cenobamate monotherapy, the average inpatient day rate per year was 0.7, vs 3.22 during previous LOT; the average ER visit rate per year was 0.27, vs 0.83 for previous LOT. 43.8% of patients had no inpatient stay, ER visit, or new LOT during cenobamate monotherapy. The average rate of new status epilepticus per year was 0.03 during cenobamate monotherapy, vs 0.13 during previous LOT; patients averaged 10.22 hours in epilepsy monitoring units, vs 10.95 hours during previous LOT. 

Conclusions:

Patients taking cenobamate monotherapy, inclusive of the titration period, experienced nominally fewer inpatient days and ER visits and lower rates of status epilepticus vs previous LOT.