PLACEBO-CONTROLLED STUDY OF THE EFFICACY AND SAFETY OF LAMOTRIGINE INPATIENTS WITH PARTIAL SEIZURES

We evaluated the efficacy and safety of lamotrigine (300 and 500 mg/da y) as add-on therapy in a multicenter, randomized, double-blind, paral lel-group, placebo-controlled study of 216 patients with refractory pa rtial seizures. During 6 months of treatment, median seizure frequency decreased by 8% with placebo, 20% with 300 mg lamotrigine, and 36% wi th 500 mg lamotrigine. Seizure frequency decreased by greater-than-or- equal-to 50% in one-third of the 500-mg group and one-fifth of the 300 -mg group. Reductions in seizure frequency and seizure days were stati stically significant, compared with placebo, for the 500-mg group but not the 300-mg group. Most adverse events were minor and resolved over time. Nine percent of patients on lamotrigine withdrew because of adv erse experiences. Lamotrigine plasma concentrations appeared to be a l inear function of dose, and the drug did not affect plasma concentrati ons of concomitant antiepileptic drugs. Lamotrigine was safe, effectiv e, and well tolerated as add-on therapy for refractory partial seizure s.