for people ages 6 months to 60 months (full criteria)
at San Francisco, California and other locations
study started
estimated completion



This is a multicenter, prospective, up to 2-year observational study in participants aged 6 to 60 months, inclusive, with SCN1A-positive Dravet Syndrome.

Official Title

ENVISION: Natural History Study of Infants and Children With SCN1A-positive Dravet Syndrome


This is a prospective natural history study designed to further define the seizure, neurodevelopmental, motor and behavioral characteristics of SCN1A-positive Dravet Syndrome in children aged 6 to 60 months, inclusive, with SCN1A mutations. The study will examine these characteristics for up to 2 years using standardized assessments and will also explore the impact of the disease on parents/caregivers and health care resource utilization (HCRU).


Dravet Syndrome severe myoclonic epilepsy epilepsy severe myoclonic epilepsy of infancy SMEI SCN1A related seizure disorder epileptic encephalopathy Epilepsies, Myoclonic Syndrome No Intervention


You can join if…

Open to people ages 6 months to 60 months

  • Confirmed SCN1A mutation.
  • Normal development prior to onset of first seizure as defined by the Centers for Disease -Control and Prevention (CDC 2019).
  • Onset of seizures between age 3 and 15 months, inclusive.

You CAN'T join if...

  • Copy number variant of SCN1A, including SCN1A microdeletion, if affecting other genes.
  • SCN1A mutation present on both alleles. Known pathogenic or clinically suspected mutation in a seizure-associated gene besides SCN1A.
  • Confirmed mutation in a gene besides SCN1A, as determined by an Independent Adjudication Committee, that is known to increase the severity of the seizure phenotype.
  • Participant has a known gain-of-function genetic mutation, as defined by functional studies, including p.Thr226Met.
  • History of notable developmental deficit that was evident prior to seizure onset.
  • Known central nervous system structural abnormality as found on magnetic resonance imaging or computed tomography scan of brain.
  • Participant is currently taking or has taken for 6 or more consecutive weeks anti-seizure medications (ASMs) at a therapeutic dose that are contraindicated in SCN1A-positive Dravet Syndrome, including sodium channel blockers.
  • Known concomitant genetic mutation or clinical comorbidity that potentially confounds typical Dravet phenotype.


  • UCSF Benioff Children's Hospital accepting new patients
    San Francisco California 94143 United States
  • Children's Hospital Los Angeles accepting new patients
    Los Angeles California 90027 United States


accepting new patients
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