Abstracts

Rationale: Lacosamide (LCM) is an antiepileptic drug approved in 2008 by FDA and EMEA as adjunctive treatment for refractory focal epilepsies. It enhances the slow inactivation of voltage-gated sodium channels. Efficacy has been shown in addiction to non-channel blockers and with classical channel blockers, however the adverse effects shown by LCM are higher in this second group. We analyze efficacy and safety in patients treated with LCM as an add-on treatment in patients with focal epilepsies after 3 and 6 months.Methods: Prospective observational study performed in 4 secondary and tertiary hospitals in Galicia, Spain from November 2012. From the 192 patients included, 147 were treated for 3 months with LCM as an add-on treatment for focal epilepsies. In this group we analyzed demographic characteristics, efficacy, concomitant treatment and safety of LCM. Statistical analysis was performed with SPSS version 19.0. A value of p < 0.05 was considered significant. Response to LCM was achieved if a diminution of 50% of seizures was reported. Concomitant number and dosage of AEDs before and after LCM usage were also determined. Variation of both parameters was performed using Wilcoxon test.Results: We analyzed data from 147 patients with a mean of 43.5 17.2 years old. 53.7% were male. 91.5% suffered from refractory epilepsy and 8.5% received LCM after previous intolerance to 2 AEDs. Mean time of evolution of epilepsy was 18.7 15.6 years. 38.4% suffered from cryptogenic epilepsy. Temporal origin was the most frequent localization (48.3%). Median seizure frequency before introducing lacosamide was 2.3 [1, 5] seizures per month. 46.3% of patients were treated with 2 antiepileptic drugs (AEDs) and the most frequent combination was a sodium channel blocker and a non-sodium channel blocker (32.7%). Mean number of AEDs previously tried was 4.2 2.5. In the moment of the inclusion, 46.3% of patients were receiving 2 AEDs, 27.2% were receiving 1 AED, 15.0 % were receiving 3 AEDs and 11.6% were receiving 4 AEDs. After 3 months, 60% of patients experienced 50% improvement. Among them, 31.4% of patients are free of seizures. 12.2% of patients referred adverse effects after 3 months being dizziness (5 %) and instability (2.9 %) the most frequently reported. 139 patients (94.6%) continue with LCM after three months. Mean dosage of LCM was 258.9 95.9 mg/day at 3 months. Number of concomitant AEDs were significantly reduced from 2.1 0.9 to 1.7 0.9 (p<0.001). Dosage of concomitant channel blockers was significantly reduced for all AEDs (CBZ, ESL, LMT, OXC, PHT) (p<0.05). LCM Addition also led to a significant reduction of CLB, LEV and VPA (p < 0.05). 48 patients were followed for 6 months. 58.33% remained responders to LCM and 31.25% of them are free of seizures.Conclusions: LCM offers a safety profile and efficacy. High percentage of responders may be due to a less refractory population than clinical essays (seizure frequency, previous treatments, concomitant AEDs). Considering it as an early medical treatment for focal refractory epilepsies is proposed. Longer follow-up is needed to certify this early response to LCM.