Impact of lifetime antiepileptic drug history on cenobamate efficacy in adults with focal epilepsy

Purpose

To evaluate the efficacy of cenobamate (CNB) in adults with focal epilepsy based on the number of previous lifetime antiseizure medications (ASMs).

Methods

Twenty patients receiving add-on treatment with CNB with <6 lifetime ASMs were retrospectively compared to 20 Patients with >10 ASMs and approximately the same age. Efficacy was assessed at 3, 6, and 12 months following CNB initiation.

Results

In patients with <6 lifetime ASMs, seizure frequency significantly decreased at 3, 6, and 12 months (p = 0.03, 0.027, 0.048, respectively), while no significant changes were observed in the >10 lifetime ASM group. The median percentage of seizure reduction in the <6 lifetime ASMs group was 58 % at 3 months, 50 % at 6 months, and 92 % at 12 months, compared to 36 %, 50 %, and 42 % in the >10 lifetime ASM group. The seizure-free rate was significantly higher in the <6 lifetime ASMs group at all-time points (p < 0.01), despite a lower median daily dose of CNB in this group. There was a trend toward higher responder rates at 12 months in the <6 lifetime ASMs group, again despite the lower median daily dose of CNB.

Conclusions

This study highlights greater efficacy of CNB in patients with <6 lifetime ASMs, showing a significantly higher seizure-free rate and greater seizure reduction compared to those with >10 lifetime ASMs. Despite lower overall response in the latter group, CNB treatment still provided meaningful benefits in highly drug-resistant epilepsy.