Real-world retention of newer antiseizure medications in children with epilepsy – a nationwide study

Abstract Background Children with epilepsy are rarely included in clinical drug trials, delaying approval and introduction of new antiseizure medications (ASMs). To circumvent this we used population-wide register data to study retention, an intergrated meassure of effect and tolerability, of newer ASMs used in children in Sweden; brivaracetam, cenobamate, lacosamide, and perampanel. Methods All cases of incident epilepsy and subsequent ASM treatment 2007-2021 were identified using national registers. Retention rates of newer ASMs were calculated using Kaplan-Meier analyses. Cox regression was used to investigate how factors associated with therapy-resistant epilepsy affected risk of discontinuing each drug and to compare the risk of discontinuing each of the newer ASMs to levetiracetam, the most common ASM, in patients matched for age at epilepsy onset and number of previously tried ASMs. Results Out of 16431 included 54% were male, median age 7 years [Q1-Q3:3-12]. Developmental or intellectual disorders, followed by neurological malformations, were the most common comorbidities. In 2023 ∼10% of all ongoing treatments started