Zorevunersen in Children and Adolescents with Dravet Syndrome

To the Editor: The studies by Laux et al. (March 5 issue) 1 of zorevunersen mark an advance in targeting SCN1A (sodium channel type 1 alpha subunit gene) haploinsufficiency in Dravet syndrome. Although the reductions in the frequency of convulsive seizures and improvements in adaptive behavior are compelling, the inclusion of patients 2 to 18 years of age leaves a critical mechanistic question unresolved: to what extent does the timing of intervention dictate the ceiling of therapeutic benefit? Dravet syndrome is a progressive encephalopathy in which early-onset hyperexcitability drives cumulative neurodevelopmental decline. 1,2 Given that zorevunersen restores physiologic Na V 1.1 levels, 1,3 its efficacy . . .