Purpose: Perampanel (PER) was added to the anticonvulsant regimen of 71 patients with Lennox-Gastaut Syndrome (LGS) to evaluate its efficacy against seizures and its tolerability.
Method: This team evaluated at 3 month intervals 62 with pure LGS and 9 with LGS-like epileptic encephalopathy (28 females, 43 males, mean age 40.1 ± 11.5 yrs, median 38, range 20–71) in whom PER was introduced by 2 mg steps at 2- to 4-week intervals up to 6 mg/day, with possible dose reduction or increases after that. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines were followed.
Results: Mean PER exposure was 538.9 days ± 425 (median 429), with 44 patients (62%) on PER at last follow-up. About 2/3 of patients were responders, including 35.2% that had a at least a 75% decrease in their seizures. Among these 16.9% had a 90% or greater decrease. No improvement was seen in 14 patients; 5 had a less than 50 % response, and 6 had seizure aggravation. Therefore, 25 (35.2%) were considered non-responders. Half of the patients developed at least one side-effect. Significant negative changes in behavior were noted in 1/3 of the cases, including irritability (8.5%) and aggressivity (7%). In contrast, 4 patients reported positive behavioral and psychological well-being side-effects.
Conclusions: This retrospective, open-label study provides evidence that perampanel (PER) may significantly help in Lennox-Gastaut syndrome (LGS). PER should be tried in LGS patients who are not satisfactorily controlled. Its use may be limited in some patients due to behavioral side-effects occurring, particularly at doses at or above 6 mg/d.