Multicenter Double-Blind, Randomized, Placebo-Controlled Trial of Levetiracetam as Add-On Therapy in Patients with Refractory Partial Seizures


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Summary: Purpose: To evaluate the efficacy and tolerability of levetiracetam (LEV, Keppra) as add-on therapy in patients with refractory partial seizures.

Methods: In this European multicenter, double-blind, randomized, placebo-controlled trial, LEV (500 or 1,000 mg twice daily) was compared with placebo as add-on therapy in 324 patients with uncontrolled simple or complex partial seizures, or both, with or without secondary generalization. After enrollment, three parallel groups were assessed during a baseline period of 8 or 12 weeks, followed by a 4-week titration interval and a 12-week evaluation period.

Results: LEV significantly decreased partial seizure frequency compared with placebo. A reduction in seizure frequency of geqslant R: gt-or-equal, slanted50% occurred in 22.8% of patients in the 1,000-mg group and 31.6% of patients in the 2,000-mg group, compared with 10.4% of patients in the placebo group. Administration of LEV did not affect plasma concentrations of concomitant an-tiepileptic drugs or alter vital signs or laboratory parameters. No significant difference in the incidence of adverse events was observed between treatment groups (70.8% for the 1,000-mg group and 75.5% for the 2,000-mg group), or between the LEV and placebo groups (73.2% for placebo group). The most commonly reported adverse effects in the LEV group were asthenia, headache, and somnolence.

Conclusions: The antiepileptic efficacy and tolerability of LEV (1,000 mg/d and 2,000 mg/d, administered in two divided doses) as add-on therapy was established in patients with refractory partial seizures in this clinical study.