Long-term therapeutic effect of eslicarbazepine acetate in children: An open-label extension of a cognition study in children aged 6–16 years

Objective: In Europe, eslicarbazepine acetate (ESL) is approved as adjunctive therapy for the treatment of focal seizures (FS) in children aged >6 years. In the US, ESL is approved as both monotherapy and adjunctive therapy for the treatment of FS in patients aged ≥4 years. In a phase II study of children aged 6–16 years with FS, ESL had no significant effects on attention or behavioral functioning and decreased seizure frequency during double-blind therapy and a 1-year open-label extension (OLE). This report presents data from an additional 2-year OLE of the phase II study. Methods: Previous recipients of ESL or placebo were treated with open-label ESL (10–30 mg/kg/day, adjusted for clinical response and/or adverse events [AEs]). Safety was assessed by incidence of treatment-emergent AEs (TEAEs). Efficacy endpoints were treatment retention time and change from baseline in Clinical Global Impression-Severity (CGI-S) scale scores. Results: Forty-two patients entered and 31 (73.8%) completed the 2-year OLE. Median treatment retention time was 735 (95% confidence interval 728–741) days. Seven patients (17% of total, 23% of completed) experienced ≥1 TEAE during the 2-year OLE, mostly of mild or moderate intensity. The incidence of serious TEAEs was low (n = 2; 5% of total, 6% of completed) and none were related to ESL. One child was withdrawn because of splenomegaly that was considered possibly related to ESL. The only change from baseline in CGI-S was a 0.5-point reduction in the severity of illness score. All findings were consistent across patient subgroups based on previous double-blind treatment (placebo or ESL) and patient age (6–11 or 12–16 years). Conclusions: The majority of patients remained on ESL during the 2-year OLE, and treatment efficacy was maintained. Adverse events were consistent with the known safety profile of ESL, and no new safety signals were identified.