In Dravet syndrome (DS; MIM607208), a severe form of DEE which is primarily caused by SCN1A haploinsufficiency, treatment in a DS mouse model with the antisense oligonucleotide STK-001 (also known as ASO-22) increases the production of functional Scn1a mRNA and Nav1.1 protein. The gene discussed is SCN1A; the disease is encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy.