Abstracts

Rationale: Cenobamate is an antiseizure medication (ASM) is approved in the United States as adjunctive and monotherapy for the treatment of focal seizures in adults. Cenobamate 100, 200, and 400 mg/d demonstrated highly statistically significant reductions in focal seizures compared to placebo in an adequate, well controlled trial. The dosing recommendations for cenobamate followed the design of a large, open-label safety study initiated to mitigate the incidence of a serious adverse event, DRESS syndrome, identified during early clinical development. The recommended initial dose of cenobamate is 12.5 mg/d for two weeks, followed by 25 mg/d for two weeks, then 50 mg/d for two weeks, and then the dose is increased in bi-weekly increments by no more than 50 mg/d to the recommended maintenance dose of 200 to 400 mg/d. Real world maintenance doses of cenobamate may differ from the recommended maintenance doses in order to give healthcare professionals and patients more flexibility in dosing. Using a large United States electronic medical record (EMR) data source (Truveta) we explored the maintenance doses of cenobamate prescribers are employing.


Methods: Dispensing information from the Truveta data platform, which includes structured and unstructured EMR data on approximately 1.1 million patients with a diagnosis code for epilepsy, was accessed on May 13, 2024 to examine maintenance doses of cenobamate. A patient’s maintenance dose was determined by looking backward for at least 90 or 180 days (using days’ supply or fill dates) from the patient’s last consistently dispensed dose of cenobamate between 50-400 mg/d available in the data.

Results: There were 4,306 unique patients with epilepsy identified as having ≥1 cenobamate dispensing record for any length of time. Of these patients, 1,813 were dispensed cenobamate for ≥90 days and 1,127 were dispensed cenobamate for ≥180 days at a maintenance dose between 50-400 mg/d. The remaining patients were dispensed the medication for < 90 days. The percentage of patients receiving 50, 100, 150, and 200 mg/d for ≥180 days were 8.9%, 21.5% 16.1% and 50.9%, respectively (Figure 1). A similar percentage of patients received 50, 100, 150, and 200 mg/d, respectively, for ≥90 days (Figure 1). Few patients (2.6%) received more than 200 mg for ≥180 days.

Conclusions: While around half of patients received a maintenance dose of 200 mg/d, nearly just as many received a maintenance dose of less than 200 mg/d (eg, 100 or 150 mg/d). Further studies are warranted to examine if exposure to the same dose for at least 180 days could be a proxy measure for effectiveness. The range of maintenance doses of cenobamate observed in this real-world analysis suggests that healthcare providers are individualizing cenobamate-dosing regimens for their patients.

Funding: Funded by SK Life Science, Inc.