EFFICACY OF FELBAMATE IN CHILDHOOD EPILEPTIC ENCEPHALOPATHY (LENNOX-GASTAUT SYNDROME) (REPRINTED FROM NEW-ENGLAND JOURNAL OF MED, VOL 328, PG 29, 1993)

Background. The Lennox-Gastaut syndrome is a childhood disorder charac terized by multiple types of seizures, mental retardation, characteris tic electroencephalographic abnormalities, and resistance to standard antiepileptic drugs. Felbamate is an investigational antiepileptic dru g with a preclinical profile that suggests it would be effective in pa tients with multiple types of seizures. In controlled clinical trials, felbamate was superior to placebo in reducing frequency of refractory partial-onset seizures. Methods. We studied the efficacy of felbamate in 73 patients ranging in age from 4 to 36 years who had the Lennox-G astaut syndrome. During a 28-day base-line phase, the patients receive d their usual antiepileptic therapies. At the end of this phase, felba mate or placebo was administered for 70 days in addition to the curren t antiepileptic medications. The dosage of felbamate was titrated duri ng the first 14 days of the treatment phase to a maximum of 45 mg/kg o f body weight per day or 3,600 mg/d, whichever was less. The placebo e fficacy variables were the total number of seizures counted during a 4 -hour period of video recording, parents' or guardians' global evaluat ions of the patients' quality of life, and the total number of atomic seizures, as reported by parents or Results. The patients treated with felbamate had a 34% decrease in the frequency of atomic seizures, as compared with a 9% decrease in the patients who received placebo (P = 0.01). The felbamate-treated patients had a 19% decrease in the total frequency of seizures, as compared with a 4% increase in the placebo g roup (P = 0.002). The global-evaluation scores were significantly high er in the felbamate group than in the placebo group from day 49 to the end of the study. There were no significant differences in the freque ncy of seizures occurring during video monitoring, but there was a sig nificant reduction (P = 0.017) in the number of tonic-clonic seizures during the maintenance period in the felbamate group. The types and fr equency of side effects were similar in the two treatment groups. Conc lusions. Felbamate is beneficial in patients with the Lennox-Gastaut s yndrome.