Seizure-free Days Observed in Randomized Placebo-controlled Add-on Trials with Levetiracetam in Partial Epilepsy

Purpose: We examined the effect of adjunctive levetiracetam (LEV; 1,000 to 3,000 mg/day) on the number of seizure-free days gained per quarter in adult patients with refractory partial-onset epilepsy. Methods: The treatment effect was studied in a meta-analysis using individual patient data of a subpopulation of patients (n = 846) emerging from the three randomized, double-blind, placebo-controlled, phase III trials (n = 904). Results: Adding LEV effectively increased the number of days without seizures by 5.19 days per quarter [95% confidence interval (CI), 3.63-6.76; p = 0.0001; titration and stable dose periods]. Conclusions: LEV adjunctive treatment shows a clear benefit in terms of seizure-free days gained for patients with refractory epilepsy. This gain is significant for the pooled and for each LEV dose compared with placebo.