Post-authorisation study of eslicarbazepine as treatment for drug-resistant epilepsy: preliminary results

Eslicarbazepine acetate (ESL) is a new antiepileptic drug (AED) and an analogue to carbamazepine (CBZ) and oxcarbazepine (OXC). In this study, we evaluate initial therapeutic response to ESL and events in the change from CBZ and OXC.

We evaluated 61 patients with a broad spectrum of drug-resistant epilepsies in a cross-sectional study. The switch from CBZ and OXC to ESL was carried out in a single night at ratios of 1:1.3 and 1:1mg respectively.

The most common form of epilepsy was temporal lobe epilepsy (62.3%). The most common aetiology was mesial temporal sclerosis (26.2%). Mean follow-up time was 4.7±3.2 months. In 40 patients with a minimum follow-up period of 3 months, monthly median seizure frequency dropped by 63.6% (P<.001) and a reduction of 80% or more was recorded in 30%. Adverse events (AEs) occurred in 54%; all appeared during the titration phase. They were more frequent at doses in excess of 800mg (73.9% vs. 47.4%; P=.042). The most common AE was dizziness (34.4%), which was commonly associated with VPA, LTG and/or LCS consumption (19.2% vs. 45.7%; P=.031). The retention rate at 3 months was 75.4%. A total of 25 patients replaced CBZ or OXC treatment with ESL; any AEs were transient (69.2% for CBZ and 33% for OXC; P=.073). At 3 months after the treatment change, median seizure frequency had decreased by 20% (P<.075).

ESL is effective in the treatment of focal epilepsies and its early retention rate is > 70%. AEs occurred during the titration phase and corresponded to associated AEDs. A rapid change from CBZ and OXC to ESL treatment can be safely performed.