Felbamate Shows Sustained Use and Safety in Pediatric Epilepsy: Study
According to new research more than half of children with refractory epilepsy treated with felbamate remain on therapy for at least one year without treatment failure, and contemporary use appears largely safe. Felbamate is indicated for focal seizures and Lennox-Gastaut syndrome; however, its clinical use has declined due to rare but severe idiosyncratic hematologic and hepatic toxicities. The study was presented at the American Epilepsy Society by Dominique Cooper.
Children with drug-resistant epilepsy often require multiple ASMs and treatment options are further limited over time. Understanding current outcomes with felbamate is particularly important in populations such as Lennox-Gastaut syndrome, where seizure control often remains unsatisfactory despite poly-therapy.
Patients who were less than 21 years of age and were treated with felbamate at the Children's Hospital of Philadelphia between 2013 and 2023 were retrospectively involved in the cohort. Demographic and clinical information was manually retrieved from the medical records. The time to treatment failure was analyzed on Kaplan-Meier survival curves, where treatment failure was defined as either discontinuation of felbamate or addition of another antiseizure medication.
The study involved 27 patients, including 15 females, with a median follow-up duration of 45 months (range 0.4–94 months). Epilepsy types included focal epilepsy in 30% (n=8), generalized epilepsy in 30% (n=8), mixed epilepsy in 33% (n=9), and undetermined epilepsy in 7% (n=2). The majority of patients had Lennox-Gastaut syndrome (73%). The mean age at the start of felbamate was 10.3 ± 4.6 years, and the range was from 1.8 to 17.8 years. At the beginning of treatment, patients were taking a median of 3 concomitant ASMs (range 1–6) and previously tried a median of 5.5 ASMs (range 2–16), reflecting a highly treatment-resistant cohort.
Key Findings
The median time to felbamate treatment failure was 12.5 months, 95% CI 5.7–26.0 months.
The probability of remaining on felbamate without treatment failure was 52%, 95% CI 32–69% at 12 months and 34%, 95% CI 16–53% at 24 months.
In total, 52% of patients discontinued felbamate during the observation period.
Among these, discontinuations were due to lack of efficacy in 43%, lack of tolerability in 29%, and for both tolerability and efficacy issues in 21%.
One patient did discontinue felbamate after becoming seizure-free.
Side effects were infrequent and reversible.
Three patients (11.1%) developed leukopenia, one patient (3.7%) anemia, and one patient (3.7%) transaminitis while on felbamate.
All laboratory abnormalities resolved once felbamate was discontinued, and no adverse event could be conclusively attributed to felbamate.
No aplastic anemia or hepatic failure occurred in the course of this study.
In this modern pediatric population, treatment with felbamate did not result in failure in >50% of children treated for at least a year. Felbamate was discontinued more often for lack of efficacy than for tolerability or safety concerns; the serious adverse effects encountered were rare, reversible, and not conclusively attributed to the drug.
Reference:
Felbamate treatment persistence in children with epilepsy. (n.d.). Default. Retrieved December 10, 2025, from https://aesnet.org/abstractslisting/felbamate-treatment-persistence-in-children-with-epilepsy
