Zorevunersen (STK-001) is an experimental treatment administered intronically to children and adolescents aged 2–18 years with Dravet syndrome, a severe epilepsy caused by mutations in the SCN1A gene that reduce the Nav1.1 protein.[1][2] The MONARCH (NCT04442295) and ADMIRAL (2020-006016-24) studies evaluated the safety, tolerability and effects of the drug in patients with disease onset before 12 months of age.[1] In patients receiving multiple doses of 70 mg, 80% of responders achieved a ≥50% seizure reduction at 3 months and 77.8% at 6 months from the last dose.[1] Median seizure reduction was 85% at 3 months and 74% at 6 months in patients with 2–3 doses of 70 mg, despite taking 3 or more antiepileptics.[2] Treatment improved adaptive behavior (Vineland-3, eg reception communication +5,778 points), overall clinical status (CGI-C, CaGI-C) and quality of life (EQ-VAS +7,756 points).[1][2] Zorevunersen was generally well tolerated, with 29.6% of patients experiencing drug-related adverse events, most commonly increased cerebrospinal fluid protein (13.6%) and post-procedural vomiting (4.9%); none discontinued treatment due to side effects.[1]