The Children's Adaptive Deep Brain Stimulation for Epilepsy Trial (CADET)

April 1, 2026 updated by: University College, London

The Children's Adaptive Deep Brain Stimulation for Epilepsy Trial (CADET): a Pivotal, Randomized, Controlled, Double-blinded Multi-site Clinical Trial of Deep Brain Stimulation to Treat Children With Lennox-Gastaut Syndrome

The CADET Trial will investigate the effectiveness of deep brain stimulation (DBS) to reduce the frequency of seizures in children with Lennox-Gastaut syndrome (LGS). The CADET Trial will use a non-CE/UKCA marked device - the Picostim DBS system.

The SMART-DBS study is a sub-study of the CADET Trial. SMART-DBS will investigate the application of adaptive DBS for the treatment of children with LGS. Children will be recruited after they exit from either the prior 'CADET Pilot Study' or 'CADET Trial' - meaning that these children will already be receiving therapy with an already implanted Picostim device.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

All participants will complete a 4 week baseline assessment phase, then surgical implantation of the Picostim device and then a 4 week recovery phase. The participants will thereafter be randomised (1:1) and double-blinded to either an 'early stimulation' (DBS device switched on) or an 'delayed stimulation' (DBS device switched off) arm. Children allocated to receive early stimulation will complete 36 weeks of immediate active stimulation and children allocated to delayed stimulation will complete 12 weeks of inactive stimulation followed by 24 weeks of active stimulation.

The primary endpoint for all participants in the trial will be following 24 weeks of active stimulation. Secondary outcomes will be compared between the early and delayed stimulation arms following the first 12 weeks of the controlled phase.

The SMART-DBS study will recruit participants from the CADET Trial and the preceding CADET Pilot study. In both the CADET Trial and CADET Pilot studies, participants were fitted with the Picostim device and the device remains active. Participants who potentially meet the eligibility criteria will be provided with the PIS to consider participation in the adaptive DBS study.

Study Type

Interventional

Enrollment (Estimated)

22

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • United Kingdom
      • London, United Kingdom
        • Recruiting
        • Great Ormond Street Hospital NHS Foundation Trust
        • Contact:
          • Rory Piper, MRCS
        • Contact:
          • Martin Tisdall, FRCS

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

No

Description

Children enrolled in this study must:

  • Be 5-14 years of age at consent.

  • Have a diagnosis of LGS, as determined by:

    • Slow (<3.0Hz) spike-and-wave pattern and/or fast wave pattern (tonic seizures) detected on EEG at least six-months prior to the enrolment into the baseline period
    • History of drop seizures (tonic, atonic, or tonic-clonic) that precedes at least six-months prior to the enrolment into the baseline period
  • Have experienced at least 10 seizures in the four weeks prior to enrolment.
  • Have tried and not responded to two or more antiseizure medications prior to enrolment.
  • Be taking one or more anti-seizure medication(s) at a stable dose for at least the four weeks prior to enrolment.
  • Have a carer who is willing for their child's maintenance anti-seizure medications and ketogenic diet (if relevant) to be unaltered for the trial duration.
  • Have a carer who is willing and able to comply with all the requirements of the study, including the completion of the seizure diary and periodic device charging.

Children enrolled in this study must not:

  • Have received prior deep brain stimulation insertion.
  • Have an active ('on') vagus nerve stimulator (or active within the six months prior to the baseline period).
  • Have had a change in their anti-seizure medication prescription or stopped their ketogenic diet within the last 4 weeks
  • Have started or made changes to the prescription of a ketogenic diet within the last 12-weeks
  • Have abnormal thalamic anatomy detected on imaging that would render DBS either unsafe or unfeasible.
  • Have a bleeding disorder(s).
  • Have a medical condition(s)/factor(s) that would increase their anaesthetic risk to an unacceptable level.
  • Have a nickel allergy.
  • Be pregnant.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Early stimulation
Active stimulation
Device: Deep Brain Stimulation
Picostim DBS Device
Sham Comparator: Delayed stimulation
Inactive stimulation
Device: Deep Brain Stimulation
Picostim DBS Device

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Seizure frequency reduction
Time Frame: 24 weeks of active stimulation compared to baseline
Seizure frequency reduction measured on carer-recorded seizure diaries
24 weeks of active stimulation compared to baseline

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Seizure frequency
Time Frame: 8-12 weeks following randomisation between the active and inactive stimulation arms
Seizure frequency reduction measured on carer-recorded seizure diaries
8-12 weeks following randomisation between the active and inactive stimulation arms
Seizure frequency
Time Frame: 24 weeks of active stimulation compared to baseline
Seizure frequency reduction measured on scalp EEG
24 weeks of active stimulation compared to baseline
Seizure frequency
Time Frame: 8-12 weeks following randomisation between the active and inactive stimulation arms
Seizure frequency reduction measured on scalp EEG
8-12 weeks following randomisation between the active and inactive stimulation arms
Seizure severity
Time Frame: 24 weeks of active stimulation relative to baseline and comparison 12 weeks following randomisation between the active and inactive arms
Seizure severity (according to the Hague Seizure Severity Scale). The HSSS scores range from 13 (least severe) and to 53 (most severe).
24 weeks of active stimulation relative to baseline and comparison 12 weeks following randomisation between the active and inactive arms
Quality of life (PedsQL)
Time Frame: After 24-weeks of active stimulation, and 12 weeks following randomisation between the active and inactive stimulation arms
The PedsQL (Pediatric Quality of Life Inventory) questionnaire provides a quantitative score ranging from 0 (worst possible QoL) to 100 (best possible QoL) (https://www.pedsql.org/).
After 24-weeks of active stimulation, and 12 weeks following randomisation between the active and inactive stimulation arms
Quality of life (IPES)
Time Frame: After 24-weeks of active stimulation, and 12 weeks following randomisation between the active and inactive stimulation arms
The Impact of Pediatric Epilepsy Scale (IPES) is a 12-item questionnaire that is answered by the carers of children with epilepsy that, as titled, aims to objectively measure the burden that epilepsy has on the child's life. The IPES scores range from 0 (lowest impact of epilepsy on the participant) to 33 (highest impact of epilepsy on the participant).
After 24-weeks of active stimulation, and 12 weeks following randomisation between the active and inactive stimulation arms

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University College, London

Collaborators

King's College London
King's College Hospital NHS Trust
University of Oxford
Great Ormond Street Hospital for Children NHS Foundation Trust

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 24, 2026

Primary Completion (Estimated)

January 31, 2028

Study Completion (Estimated)

January 31, 2028

Study Registration Dates

First Submitted

March 28, 2025

First Submitted That Met QC Criteria

April 4, 2025

First Posted (Actual)

April 11, 2025

Study Record Updates

Last Update Posted (Actual)

April 7, 2026

Last Update Submitted That Met QC Criteria

April 1, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 141268

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Lennox Gastaut Syndrome (LGS)

Clinical Trials on Deep Brain Stimulation

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in France

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe