Control of seizures in different stages of partial epilepsy: LACO-EXP, a Spanish retrospective study of lacosamide

• Investigated adjunctive lacosamide in 500 patients with partial-onset epilepsy
• Study treatment with lacosamide offered patients who had received up to 10 prior AEDs a chance to be seizure-free.
• Efficacy was better when lacosamide was used in the early stages of treatment.
• The mechanism of action of concomitant antiepileptic drugs appeared to be less important in early stages.
• A slower dosage–titration schedule was associated with a lower adverse event rate.

Lacosamide is approved as adjunctive therapy for focal epilepsies. The number of antiepileptic drugs (AEDs) tried is associated with prognosis. This multicenter, retrospective, observational study (LACO-EXP) in Spain in 500 adult patients with focal epilepsies examined the efficacy and tolerability of add-on lacosamide. Factors associated with better efficacy/tolerability were analyzed. After 12 months, the responder rate (≥ 50% reduction in seizure frequency) was 57.1%, and the seizure-free rate was 14.9%. Efficacy was better when lacosamide was the first or second add-on AED, although there was a small chance to be seizure-free even for patients who had received ≤ 10 prior AEDs. The mechanism of action of concomitant AEDs is important in all the stages, but differences are smaller in the early stages. Lacosamide was generally well tolerated. A slower dosage–titration schedule was associated with a lower adverse event rate. Further investigation of the timing of initiation of lacosamide add-on therapy and ideal combinations of AEDs is required.