Skip to main content
TTrialFinderData
TrialFinderData is for informational purposes only and does not provide medical advice. Always talk to your doctor.

Updated June 2026 · ClinicalTrials.gov

RECRUITINGPhase 1 / Phase 2INTERVENTIONAL

A Clinical Study to Evaluate the Safety and Efficacy of ETX101 in Infants and Children With SCN1A-Positive Dravet Syndrome

ENDEAVOR: A Clinical Study to Evaluate the Safety and Efficacy of ETX101, an AAV9-Delivered Gene Therapy in Infants and Children With SCN1A-Positive Dravet Syndrome

A Clinical Study to Evaluate the Safety and Efficacy of ETX101 in Infants and Children With SCN1A-Positive Dravet Syndrome (NCT05419492) is a Phase 1 / Phase 2 interventional studying Dravet Syndrome, sponsored by Encoded Therapeutics. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

Important: This information is not medical advice. Talk to your doctor about whether a clinical trial is right for you.

About This Trial

ENDEAVOR is a Phase 1/2, 2-part, multicenter study to evaluate the safety and efficacy of ETX101 in participants with SCN1A-positive Dravet syndrome aged ≥6 to \<36 months (Part 1A), aged ≥48 months to \<18 years (Part 1B), and aged ≥6 to \<48 months (Part 2). Part 1A follows an open-label, dose-escalation design, Part 1B follows an open-label design, and Part 2 is a randomized, double-blind, sham delayed-treatment control study.

What Stage of Research Is This?

Phase 1 trials test a new treatment for the first time in humans, focusing on safety, dosing, and how the body processes the drug. For Dravet Syndrome, a Phase 1 study typically enrolls a small number of participants — often healthy volunteers or patients who have exhausted standard treatment options. Phase 1 results determine whether a treatment moves into larger Phase 2 efficacy studies.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

With a target enrollment of 47 participants, this is a small study — typical of early-phase research, rare-disease trials, or pilot studies designed to generate preliminary signal before a larger study is launched.

Who May Be Eligible (Plain English)

Who May Qualify: - Participant must be aged between ≥6 months and \<36 months in Part 1A, ≥48 months and \<18 years in Part 1B, ≥6 months and \<48 months in Part 2. - Participant must have a predicted loss of function pathogenic or likely pathogenic SCN1A variant. - Participant must have experienced their first seizure between the ages of 3 and 15 months. - Participant must have a clinical diagnosis of Dravet syndrome or the treating clinician must have a high clinical suspicion of a diagnosis of Dravet syndrome. - Participant is receiving at least one prophylactic antiseizure medication. Who Should NOT Join This Trial: - Participant has another genetic mutation or clinical comorbidity which could potentially confound the typical Dravet phenotype. - Participant has a known central nervous system structural and/or vascular abnormality (indicated by an MRI or CT scan of the brain). - Participant has an abnormality that may interfere with CSF distribution and/or has an existing ventriculoperitoneal shunt. - Participant has received sodium channel blockers during the Pre-Dosing Seizure Period. - Participant has experienced seizure freedom for a period of 4 consecutive weeks within the 90-day period prior to willing to sign a consent form. - Participant has previously received gene or cell therapy. - Participant is currently enrolled in a clinical trial or receiving an investigational therapy. - Participant has clinically significant underlying liver disease. Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language
Inclusion Criteria: * Participant must be aged between ≥6 months and \<36 months in Part 1A, ≥48 months and \<18 years in Part 1B, ≥6 months and \<48 months in Part 2. * Participant must have a predicted loss of function pathogenic or likely pathogenic SCN1A variant. * Participant must have experienced their first seizure between the ages of 3 and 15 months. * Participant must have a clinical diagnosis of Dravet syndrome or the treating clinician must have a high clinical suspicion of a diagnosis of Dravet syndrome. * Participant is receiving at least one prophylactic antiseizure medication. Exclusion Criteria: * Participant has another genetic mutation or clinical comorbidity which could potentially confound the typical Dravet phenotype. * Participant has a known central nervous system structural and/or vascular abnormality (indicated by an MRI or CT scan of the brain). * Participant has an abnormality that may interfere with CSF distribution and/or has an existing ventriculoperitoneal shunt. * Participant has received sodium channel blockers during the Pre-Dosing Seizure Period. * Participant has experienced seizure freedom for a period of 4 consecutive weeks within the 90-day period prior to informed consent. * Participant has previously received gene or cell therapy. * Participant is currently enrolled in a clinical trial or receiving an investigational therapy. * Participant has clinically significant underlying liver disease.

Treatments Being Tested

DRUG

ETX101

ETX101 is a non-replicating, recombinant adeno-associated viral vector serotype 9 (rAAV9) comprising a GABAergic regulatory element (reGABA) and an engineered transcription factor that increases transcription of the SCN1A gene (eTFSCN1A). ETX101 is intended as a one-time intracerebroventricular (ICV) administration.

Locations (13)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

UCSF Benioff Children's Hospitals
San Francisco, California, United States
Colorado Children's Hospital
Aurora, Colorado, United States
Nicklaus Children's Hospital
Miami, Florida, United States
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, United States
Boston Children's Hospital
Boston, Massachusetts, United States
Mott Children's Hospital
Ann Arbor, Michigan, United States
Mayo Clinic
Rochester, Minnesota, United States
Nationwide Children's Hospital
Columbus, Ohio, United States
Oregon Health and Science University (OSHU)
Portland, Oregon, United States
Cook Children's Medical Center
Fort Worth, Texas, United States
The Royal Children's Hospital
Melbourne, Australia
Queen Elizabeth Hospital
Glasgow, United Kingdom
Great Ormond Street Hospital
London, United Kingdom

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05419492), the sponsor (Encoded Therapeutics), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05419492 clinical trial studying?

ENDEAVOR is a Phase 1/2, 2-part, multicenter study to evaluate the safety and efficacy of ETX101 in participants with SCN1A-positive Dravet syndrome aged ≥6 to \<36 months (Part 1A), aged ≥48 months to \<18 years (Part 1B), and aged ≥6 to \<48 months (Part 2). Part 1A follows an open-label, dose-escalation design, Part 1B follows an open-label design, and Part 2 is a randomized, double-blind, sham delayed-treatment control study. The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT05419492?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05419492?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05419492. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05419492. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-06-07 · Data from ClinicalTrials.gov.