Department of Neurology, New York University Comprehensive Epilepsy Center, New York, New York, USA Clinic of Epileptology, University of Bonn, Bonn, Germany
Controlled clinical trials and routine clinical practice demonstrate that levetiracetam is effective as add‐on therapy and appears to allow for withdrawal to monotherapy in patients who respond well in the add‐on setting. In pivotal clinical trials of adjunctive therapy with levetiracetam 1000 to 3000 mg\day (pooled data), 40% to 54% of patients experienced a 50% or greater reduction in seizure frequency, compared with 18% to 28% of patients treated with placebo. The median percent reduction from baseline in seizure frequency ranged from 36% to 68% for levetiracetam, versus 10% to 23% for placebo. Seizure freedom was achieved by 11% to 35% of those in the levetiracetam treatment group, compared with 3% to 18% of those in the placebo group. (All comparisons statistically significant versus placebo for simple partial, complex partial, and secondarily generalized seizures except for percentage of seizure‐free patients with simple partial seizures.) Clinical observations are consistent with these findings.