Efficacy of perampanel in pediatric epilepsy with known and presumed genetic etiology.

Objective: The efficacy of perampanel (PER) in pediatric epilepsy with specific etiologies has not been well established. Here, we investigated outcome and predictors of PER treatment in a pediatric cohort with known and presumed genetic etiology.

Methods: We included pediatric patients with potential genetic epilepsy who received PER treatment and underwent whole-exome sequencing (WES) from January 2020 to September 2021. All patients were followed up for >12 months.

Results: A total of 124 patients were included. Overall response rates were 51.6% and 49.6% at 6 months and 12 months, respectively. Pathogenic or likely pathogenic variants in 27 multiple genes were detected among 58 patients (46.8%) by WES. On performing multivariate logistic regression analysis, only developmental delay (OR = 0.406, P = 0.042) was a negative predictor of treatment response. However, the seizure onset age, positive WES results, and number of ASMs before PER administration were not significantly. Thirteen carriers with variants in the SCN1A gene showed a better response compared to eight patients with other sodium channels (P = 0.007), and to the other 45 patients with positive WES results (OR = 7.124, 95% CI = 1.306-38.860, P = 0.023). Adverse events were only reported in 23 patients, the most common being emotional problems.

Interpretation: PER is safe and efficacious in pediatric patients with known and presumed genetic etiology. The response rate is comparable to that reported in other pediatric populations, and lower among those with developmental delay. A gene-specific response to PER is found along with better efficacy links to pathogenic variants in the SCN1A gene.