Long-term Efficacy of Perampanel in a Child with Dravet Syndrome.

Dravet syndrome is a genetic developmental and epileptic encephalopathy (DEE) mostly due to mutations in SCN1A gene. Perampanel is a selective and non-competitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist. There is increasing experience in the use of perampanel in this syndrome; however, there is still a lack of evidence of sustained benefit years after the beginning of the treatment. We report a twelve-year-old girl who was diagnosed with Dravet Syndrome when she was 2 years old and has been on perampanel since she was 7. Her genetic test showed a de novo previously described heterozygous SCN1A mutation in the 24th exon (c.4547C>A, p.Ser1516*). She received previous antiseizure drug combinations with little benefit. When perampanel was started, there was a complete resolution of her spontaneous seizures that has continued five years later. More studies are needed to investigate if there is an association between this excellent response and the genotype of our patient.