Lafora disease (LD) is a fatal intractable adolescence-onset
progressive myoclonus epilepsy. Recently, two single-case studies reported drastic reductions in
seizures and
myoclonus with the
AMPA antagonist
perampanel and improved
activities of daily living. We proceeded to study the effect of
perampanel on 10 patients with genetically confirmed LD with disease duration ranging from 2 to 27years. Open-label
perampanel was added to ongoing medications to a mean dose of 6.7mg/day.
Seizures,
myoclonus, functional disability, and cognition scores were measured for the third and ninth months following initiation and compared with those of the month prior to the start of
therapy. Three patients withdrew because of inefficacy or side effects. Four had significant reduction in
seizures of greater than 74% from baseline. Seven had major improvement in
myoclonus with group-adjusted sum score of
myoclonus intensity reduced from 7.01 at baseline to 5.67 and 5.18 at 3 and 9months, respectively. There was no significant improvement in disability and cognition. While not universal,
perampanel adjunctive
therapy appears to confer particular benefit not commonly seen with other
antiepileptic drugs on
seizures and
myoclonus in LD. Improvement in the extremely disabling
myoclonus of LD is a major benefit in this devastating disease.