ION337 safety and tolerability in children with Dravet syndrome

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This open-label, phase 1/2 trial enrolls children aged 2–12 with genetically confirmed Dravet syndrome and a pathogenic or likely pathogenic SCN1A variant. Part 1 uses a 6-month single ascending dose (SAD) design and Part 2 uses a 24-month multiple ascending dose (MAD) period, followed by a 7-month safety follow-up. Participants must be on a stable antiseizure medication regimen and have stable non-drug epilepsy interventions before enrollment. Safety, tolerability, and dosing will be monitored through scheduled clinic visits, neurological assessments, and laboratory testing.

Why it matters

Who can join: the full rules

Key Inclusion Criteria:

1. Participant is aged ≥ 2 to ≤ 12 years old at the time of informed consent.
2. Participant has at least 1 parent or caregiver ≥ 18 years old who is willing and able to provide informed consent (signed and dated) and attend all scheduled study visits.
3. Has a documented diagnosis of DS according to the International League Against Epilepsy (ILAE) criteria and as agreed by the Epilepsy Study Consortium, Inc (ESCI).
4. Has confirmation of a pathogenic or likely pathogenic SCN1A variant.
5. Must be currently receiving ≥ 1 concomitant ASM at a stable dose/regimen for ≥ 4 weeks prior to informed consent.
6. Must have all other interventions for epilepsy (including ketogenic diet or VNS) as well as any other concomitant medications including medications for behavioral management, sleep, and supplements or nutritional support stable for ≥ 4 weeks prior to informed consent. Vagus nerve stimulator implantation must have occurred ≥ 6 months prior to informed consent.
7. Experiences the required number of major motor seizures during the Screening Period.

Key Exclusion Criteria:

1. Known brain or spinal disease that would interfere with the LP procedure or CSF circulation, or presence of other factors that would affect the safety of the LP procedure.
2. Pathogenic or likely pathogenic variant in another gene that causes epilepsy.
3. Has had prior treatment with or is currently enrolled in an interventional clinical trial for a gene therapy or for another antisense oligonucleotide (ASO) for the treatment of DS.
4. Has had treatment with or is currently enrolled in an interventional clinical trial of any other investigational drug, biological agent, or device within 30 days prior to Screening, or 5 half-lives of investigational agent, whichever is longer.
5. Current treatment with an anti-seizure medication (ASM) acting primarily as a sodium channel blocker, as maintenance treatment.
6. Prior brain surgeries including: corpus callosotomy, implantation of device for deep brain stimulation or any other palliative brain surgery intended to reduce seizure burden.

Note: Other protocol pre-specified inclusion/exclusion criteria may apply.

Where it's running

• University of Michigan Health System
  Ann Arbor, Michigan, United States Recruiting
• Mayo Clinic
  Rochester, Minnesota, United States Recruiting
• Duke University Health Systems
  Durham, North Carolina, United States Recruiting
• The Children's Hospital of Philadelphia (CHOP)
  Philadelphia, Pennsylvania, United States Recruiting
• Le Bonheur Children's Hospital
  Memphis, Tennessee, United States Recruiting
• Seattle Children's Hospital
  Seattle, Washington, United States Recruiting

Study contacts

• Study coordinator: Ionis Pharmaceuticals, Inc.
• Email: IonisDravetSyndrome@clinicaltrialmedia.com
• Phone: (844) 867-4309

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• Tracking development, seizures, and biomarkers over four years in children and young adults with SCN1A-related Dravet syndrome

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• Fintepla for Dravet Syndrome: testing brain blood flow and connections

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• PET‑MRI mapping of brainstem serotonin pathways in adults with Dravet syndrome

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• Testing BMB-101 for Absence Epilepsy and Related Conditions

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• Measuring GABA Levels in Children with Dravet Syndrome

  This study is trying to measure GABA levels in the brains of children with Dravet Syndrome to see how they compare to kids without the condition, hoping to find new ways to understand and treat the syndrome.

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• Evaluating ETX101 for treating Dravet syndrome in young children

  This study is testing a new treatment called ETX101 to see if it can help reduce seizures in young children with Dravet syndrome.

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.