Background Lacosamide (LCM) is a third-generation anti-seizure drug approved in Europe and the United States, either as a monotherapy or adjunctive therapy, to treat partial-onset seizures in adults, adolescents, and children. In Brazil, LCM is licensed for treatment only in patients older than 16 years of age. Objective To evaluate a cohort of children presenting with refractory epilepsy who received LCM as an add-on therapy and observe the response and tolerability to the LCM treatment. Methods A retrospective cohort study conducted in a tertiary health care facility, which included 26 children, aged up to 16 years, who presented with refractory epilepsy and received LCM as an add-on treatment. The follow-up visits were scheduled every 3 months until 9 months of treatment with LCM. Results After 3 months of LCM administration, in 73.1% of the children, there was a reduction of > 50% in the frequency of seizures, and this clinical improvement was maintained in most patients (73.9%) for the following 9 months. Mild (such as, somnolence and behavioral changes) or severe (seizure worsening) adverse effects were observed in two and three children respectively. Among responders to LCM, there was a higher prevalence of males, fewer concomitant anti-seizure drugs, and lower percentage of patients using sodium channel blockers. Conclusions Lacosamide should be considered as an early treatment option in pediatric patients with refractory epilepsy, mainly focal seizures.

IRF2BPL gene variants have recently been associated to developmental disability and epilepsy in children and movement disorders in adults. So far, only few cases have been reported; here we present four novel cases identified by exome sequencing, while investigating developmental delay, adult-onset cerebellar ataxia or regression.