Early Add-on Lacosamide in a Real-Life Setting: Results of the REALLY Study

Background and objectives: Many patients with epilepsy are treated with antiepileptic drug (AED) polytherapy. Several factors influence the choice of early add-on therapy, and deciding on the most appropriate drug can be difficult. This study aimed to assess the efficacy and tolerability of lacosamide as early add-on therapy in patients with partial-onset seizures. Methods: REALLY (REtrospective study of lAcosamide as earLy add-on aLong one Year) was a multicenter, retrospective, 1-year, real-life study. Patients included were aged older than 16 years, had partial-onset seizures, and were treated with lacosamide as add-on therapy after one or two prior AEDs. Data were collected retrospectively from clinical records. The primary study objective was to assess the efficacy of lacosamide over 12 months (seizure-free and responder rates), and the secondary objective was to assess the tolerability of lacosamide at 3, 6, and 12 months [adverse events (AEs) and discontinuation]. Results: One hundred and ninety-nine patients were enrolled in the study; 89 patients (44.7 %) had tried one AED and 110 patients (55.3 %) had tried two AEDs before lacosamide. At 12 months, the proportion of patients who were seizure free was 44.9 %, and 76 % of patients were responders. The seizure-free rate at 12 months for patients who had previously received one or two AEDs was 58 and 34.3 %, and the responder rate at 12 months was 83.0 and 70.4 %, respectively. The AE rate was 21.5 % at 3 months, 27.1 % at 6 months, and 31.2 % at 12 months, with 7.0 % of patients discontinuing treatment because of an AE. The most common AE reported was dizziness (11.6 %). Cryptogenic epilepsy, a higher number of prior AEDs, and the use of a sodium channel blocker at onset were associated with a worse outcome. The number of concomitant AEDs decreased over 1 year (Z = 5.89; p < 0.001). Twenty-two patients were converted to lacosamide monotherapy with at least one evaluation ≥6 months from the beginning of monotherapy conversion. Conclusions: Lacosamide was effective and well tolerated as early add-on treatment in patients who had received one or two previous AEDs.