Dravet SyndromePhase 1/2ENDEAVORNCT05419492
A Clinical Study to Evaluate the Safety and Efficacy of ETX101 in Infants and Children With SCN1A-Positive Dravet Syndrome
A Phase 1/2 study testing ETX101 in people with Dravet Syndrome, run by Encoded Therapeutics at 14 sites in 3 countries.
Trial summary
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). Read more about this study
- Who is it for?
- Ages 6 months to 17 years
- Conditions the study is for
- Dravet Syndrome
- What is being tested?
- ETX101
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 113 participants
- Where
- 14 sitesin 3 countries
- Study dates
- 14 May 2024to Jun 2034
- Phase
- Phase 1/2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 6 months to 17 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- 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 1 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 cannot join
- 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.
Trial locations and contacts
14 sites in 3 countries. Contact the study team or a site near you to ask about taking part.
14 sites in 3 countries
United States11 sites, 11 recruiting
- Recruiting
Mott Children's Hospital
Ann Arbor, Michigan, 48109
Stephanie Rau, 734-232-8474, shatchew@med.umich.edu
- Recruiting
Colorado Children's Hospital
Aurora, Colorado, 80045
Kallie Dock, 720-777-5322, Kallie.dock@childrenscolorado.org
- Recruiting
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, 60611
Jazmine Ibarra, 312-227-0967, jazibarra@luriechildrens.org
Linda Laux
- Recruiting
Nationwide Children's Hospital
Columbus, Ohio, 43205
Kaitlyn Brown, 614-722-2286, Kaitlyn.brown2@nationwidechildrens.org
- Recruiting
Duke Children's Hospital & Health Center
Durham, North Carolina, 27705
Makenzi Buchanan, 919-613-1232, Makenzi.hayes@duke.edu
- Recruiting
Cook Children's Medical Center
Fort Worth, Texas, 76104
Neurology Epilepsy Research, (682) 885-2844, neuroepilepsyresearch@cookchildrens.org
Scott Perry
- Recruiting
Nicklaus Children's Hospital
Miami, Florida, 33155
Matt Lallas, 305-662-8330, Matt.Lallas@nicklaushealth.org
Dainelys Pena Rodriguez, 786-624-3547, Dainelys.PenaRodriguez@nicklaushealth.org
- Not yet recruiting
NYU Langone Health
New York, New York, 10016
Comprehensive Epilepsy Center, 646-558-0800, CECResearchStudyInfo@nyulangone.org
- Recruiting
Oregon Health and Science University (OHSU)
Portland, Oregon, 97239
Emily Stein, steine@ohsu.edu
- Recruiting
Mayo Clinic
Rochester, Minnesota, 55905
Bridget Neja, 507-266-9150, neja.bridget@mayo.edu
- Recruiting
UCSF Benioff Children's Hospitals
San Francisco, California, 94158
Adam Numis, MD, Adam.numis@ucsf.edu
Adam Numis
United Kingdom2 sites, 2 recruiting
- Recruiting
Queen Elizabeth Hospital
Glasgow, G51 4TF
Patricia Clark, 0141 232 7600, Patricia.Clark2@ggc.scot.nhs.uk
- Recruiting
Great Ormond Street Hospital
London, WC1N3JH
Helen Cross, MD, helen.cross10@nhs.net
Australia1 site, 1 recruiting
- Recruiting
The Royal Children's Hospital
Melbourne
Prof. Ingrid Scheffer
Dr. Katherine Howell, neurology.department@rch.org.au
About this study
Official title: 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
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.
- Conditions
- Dravet Syndrome
- Being tested
- ETX101
- Keywords
- Dravet, SCN1A, DEE, developmental and epileptic encephalopathy, Dravet Syndrome, SCN1A-positive, SCN1A+
- Medical subject headings
- Epilepsies, Myoclonic, Generalized Epilepsy With Febrile Seizures Plus, Type 2
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ETX101Drug
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.
| Study group | Role | What they receive |
|---|---|---|
| Part 1 (US Only) | Experimental | Part 1A will follow an open-label, rule-based, dose-escalation design and will evaluate up to 4 dose levels of ETX101. Part 1B will follow an open-label design and will evaluate 1 dose level of ETX101. Receives: Drug: ETX101 |
| Part 2 | Sham comparator | Part 2 will follow a double-blind (up through Week 52), randomized, sham delayed-treatment control design.
There will be 2 cohorts in Part 2. A single dose level of ETX101 will be evaluated in Part 2 and participants will be randomized 2:1 to study treatment or sham procedure with delayed treatment. Receives: Drug: ETX101 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percent change in monthly countable seizure frequency (MCSF) between the Pre-Dosing Seizure Period and the Post-Dosing Assessment Period.
Measured: Between the Pre-Dosing Seizure Period and the Post-Dosing Assessment Period (defined as Week 5 to Week 52).
Secondary outcomes (10)
Change from Baseline in Bayley-4 cognitive subdomain raw score at Week 52 (Key Secondary Endpoint for Part 2).
Measured: From Baseline to Week 52.
Change from Baseline in Vineland-3 subdomain GSVs at Week 52.
Measured: From Baseline to Week 52.
Change from Baseline in Bayley-4 subdomain GSVs at Week 52.
Measured: From Baseline to Week 52.
Proportion of participants achieving ≥ 75% reduction in MCSF between the Pre-Dosing Seizure Period and the Post-Dosing Assessment Period.
Measured: Between the Pre-Dosing Seizure Period and the Post-Dosing Assessment Period (defined as Week 5 to Week 52).
Proportion of participants achieving ≥ 50% reduction in MCSF between the Pre-Dosing Seizure Period and the Post-Dosing Assessment Period.
Measured: Between the Pre-Dosing Seizure Period and the Post-Dosing Assessment Period (defined as Week 5 to Week 52).
Change from Baseline in the Vineland-3 Adaptive Behavior Composite standard score at Week 52.
Measured: From Baseline to Week 52.
Change from Baseline in Vineland-3 subdomain raw scores at Week 52.
Measured: From Baseline to Week 52.
Change from Baseline in Bayley-4 subdomain raw scores (excluding cognitive subdomain) at Week 52.
Measured: From Baseline to Week 52.
Proportion of CGI-I responders, defined as participants with a CGI-I score of 1 (Very much improved) or 2 (Much improved), at Week 52.
Measured: From Baseline to Week 52.
Proportion of CGI-S responders, defined as participants who either have a CGI-S score of 1 (Normal, not at all ill) or demonstrate a ≥2 point improvement from Baseline, at Week 52.
Measured: From Baseline to Week 52.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Jun 2022
- Study start14 May 2024
- Primary completionJun 2028 (estimated)
- Study completionJun 2034 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Dravet SyndromeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 113 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Encoded Therapeutics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Salvador Rico, M.D., Ph.D, Study director, Encoded Therapeutics
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05419492
- Sponsor's protocol ID
- ETX-DS-002
- Acronym
- ENDEAVOR
- Status last verified
- Oct 2026
- First submitted
- 10 Jun 2022
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No