Disease Directory Dravet Syndrome
Neurological

Dravet Syndrome

Also known as: Severe myoclonic epilepsy of infancy, SMEI, SCN1A epileptic encephalopathy

Prevalence

1-9 per 100,000 (Orphanet)

Onset

Infantile

Type

Autosomal dominant genetic (de novo in most cases)

Gene

SCN1A

About Dravet Syndrome

Dravet syndrome is a severe developmental and epileptic encephalopathy caused in approximately 80% of cases by de novo loss-of-function mutations in SCN1A, encoding the Nav1.1 sodium channel subunit. Onset occurs in the first year of life with prolonged febrile and afebrile seizures, followed by developmental plateau and multiple seizure types that are refractory to conventional antiseizure medications. Sodium channel blockers (e.g., carbamazepine, phenytoin) worsen seizures and are contraindicated.

Common Clinical Features

Prolonged febrile seizures Multiple seizure types (myoclonic, focal, absence) Developmental plateau Ataxia Sleep disturbance Hyperthermia-triggered seizures Behavioral problems

Clinical Trial Eligibility Tips

What to know before applying to Dravet Syndrome trials.

SCN1A variant classification (pathogenic, likely pathogenic) and functional impact are required for gene therapy trial eligibility

Sodium channel blockers are contraindicated — ensure current antiseizure medication list is provided; trials screen for contraindicated drugs

Seizure frequency diary (minimum 3 months) is a standard inclusion criterion — document baseline convulsive seizure count

Fenfluramine (Fintepla) and cannabidiol (Epidiolex) are approved add-on therapies — prior treatment history affects trial stratification

Patient Resources

Patient Organization

Dravet Syndrome Foundation

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Natural History Registry

Dravet Syndrome Patient Registry

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Orphanet

European reference resource for rare diseases (ORPHA:33069)

View on Orphanet ↗

NORD

National Organization for Rare Disorders

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Find recruiting Dravet Syndrome trials

Search 500,000+ studies from ClinicalTrials.gov, filtered for Dravet Syndrome. Updated daily.

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