69 дългосрочно лечение 28, 6% от пациентите не са получавалибили свободни от миоклонични пристъпи за поне 6 месеца и 21, 0% за поне 1 година.
In pediatric patients (4 to 16 years of age), levetiracetam efficacy was established in a double-blind, placebo-controlled study, which included 198 patients and had a treatment duration of 14 weeks.