This page is a curated list of interventional clinical trials relevant to people with Dravet syndrome in the UK and may not include all studies; families and carers should always discuss possible trial participation with their usual clinical team. Dravet Syndrome UK independently selects which clinical trials to list and how they are described; inclusion on this page does not imply endorsement of any specific study, treatment or company. For full information about these studies, including protocol details and current recruitment status, please see the official registry entry on ClinicalTrials.gov.
Traditionally, treatment for Dravet Syndrome focuses on managing seizures.
The DEE‑p SEA study is evaluating bexicaserin as an oral treatment for motor seizures in individuals with developmental and epileptic encephalopathies (DEEs).
Investigational compound: Bexicaserin
Phase: 3
Age: 2–65 years
Locations: Glasgow, London (GOSH & UCLH), Newcastle
Sponsor: H. Lundbeck A/S
Study website: https://deepdsstudy.global/
Latest news (06/12/25): Results from the phase 1/2 open label extension showed a median reduction in countable motor seizures of -60.2% at ~18 months (n=30), and -53.7% at ~24 months (n=17). No new safety concerns were observed.
As the understanding of Dravet Syndrome and SCN1A mutations has progressed, new therapies are being developed to target the underlying mechanisms. You can read all about disease-modifying treatments in our comprehensive guide here.
There are currently two compounds in clinical trials investigating disease-modifying approaches in Dravet Syndrome.
The ENDEAVOR Part 2 study is evaluating ETX‑101, a one‑time AAV9 based gene therapy, designed for children with SCN1A‑confirmed Dravet Syndrome. This double‑blind, sham‑controlled trial will assess efficacy for reducing monthly motor seizures and improving cognition/behaviour after 52 weeks.
Investigational compound: ETX‑101
Phase: Pivotal phase 2
Age: 6-48 months
Locations: Glasgow, London (recruitment opening soon)
Sponsor: Encoded Therapeutics
Study website: https://encoded.com/programs/clinical-studies/
Latest news (08/09/2026): Interim data from the phase I/II clinical trials show the treatment was well tolerated across all dose levels. For those with 52 weeks of observation following dose levels 3 and 4, reduction in countable seizure frequency was 79% and 89% respectively. Cognitively, participants who received treatment before 2 years of age showed substantial gains, with developmental trajectories approaching the range expected for neurotypical children. ETX101 has shown a favourable safety profile and has been well-tolerated across all four dose levels with asymptomatic transaminase elevations and thrombocytopenia being the most common adverse events.
(Recruitment closed) EMPEROR Study (NCT06872125)
The EMPEROR study will assess zorevunersen, a disease‑modifying antisense therapy, in people with SCN1A-confirmed Dravet Syndrome. This double‑blind, sham‑controlled trial will assess efficacy for reducing major motor seizures and improving cognition/behaviour over 52 weeks, with an open-label extension for eligible participants.
Investigational compound: Zorevunersen
Phase: 3
Age: 2-17 years
Locations: Sheffield, Glasgow, London
Sponsor: Stoke Therapeutics & Biogen
Study website: https://www.emperorstudy.com/en-GB
Latest news (03/09/2026): Patients treated with zorevunersen continue to experience durable reductions in seizures and ongoing improvements in cognition and behaviour. Zorevunersen continues to be generally well tolerated, with some patients treated for more than 5 years. Elevated CSF protein is the most common treatment-emergent adverse event, with no serious clinical manifestation.
Our new article explains what these therapies are and how they differ from current treatments, what they may (and may not) be able to change, why they’re so challenging to develop, and the different approaches currently in progress, from antisense oligonucleotides (ASOs) to gene regulation therapy.
Led by Professor Helen Cross and Professor Andreas Brunklaus, this webinar provides an overview of current and development therapies for Dravet Syndrome.
Lead researcher: Dr Jenna Carpenter
