Eslicarbazepine acetate as adjunctive therapy in adult patients with partial epilepsy.

OBJECTIVE

To investigate the efficacy and safety of once-daily eslicarbazepine acetate (ESL) when used as add-on treatment in adults with > or = 4 partial-onset seizures per 4-week despite treatment with 1 to 3 antiepileptic drugs (AEDs).

METHODS

This double-blind, parallel-group, multicenter study consisted of an 8-week observational baseline period, after which patients were randomized to placebo (n=100) or once-daily ESL 400 mg (n=96), 800 mg (n=101), or 1200 mg (n=98). Patients then entered a 14-week double-blind treatment phase. All patients started on their full maintenance dose except for those in the ESL 1200 mg group who received once-daily ESL 800 mg for 2 weeks before reaching their full maintenance dose.

RESULTS

Seizure frequency per 4-week (primary endpoint) over the 14-week double-blind treatment period was significantly lower than placebo in the ESL 800 mg and 1200 mg (p<0.001) groups. Responder rate (> or = 50% reduction in seizure frequency) was 13.0% (placebo), 16.7% (400 mg), 40.0% (800 mg, p<0.001), and 37.1% (1200 mg, p<0.001). Median relative reduction in seizure frequency was 0.8% (placebo), 18.7% (400 mg), 32.6% (800 mg, p<0.001), and 32.8% (1200 mg). Discontinuation rates due to adverse events (AEs) were 3.0% (placebo), 12.5% (400 mg), 18.8% (800 mg), and 26.5% (1200 mg). The most common (>5%) AEs in any group were dizziness, somnolence, headache, nausea, diplopia, abnormal coordination, vomiting, blurred vision, and fatigue. The majority of AEs were of mild or moderate severity.

CONCLUSIONS

Treatment with once-daily eslicarbazepine acetate 800 mg and 1200 mg was more effective than placebo and generally well tolerated in patients with partial-onset seizures refractory to treatment with 1 to 3 concomitant AEDs.