EEG Dynamics in Lennox-Gastaut Syndrome Patients Undergoing Fenfluramine Treatment

August 4, 2026 updated by: University of Chicago
This study plans to learn if certain markers found during electroencephalogram (EEG) analysis could predict fenfluramine responsiveness to give clinicians greater insight into the effectiveness of fenfluramine in people with Lennox Gastaut Syndrome (LGS).

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Enrolling by invitation

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
20

Contacts and Locations

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

Study Locations

  • United States
    • Illinois
      • Chicago, Illinois, United States, 60637
        • University of Chicago

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Child
  • Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Patients at University of Chicago who have been diagnosed with Lennox-Gastaut Syndrome (LGS)

Description

Inclusion criteria:

  • Children and adults aged 2 to 35 years
  • Have a confirmed diagnosis of Lennox-Gastaut Syndrome (LGS), validated by the Epilepsy Study Consortium
  • Documented seizure onset at age 11 years or younger, accompanied by multiple seizure types, specifically including tonic seizures and atonic or tonicatonic seizures.
  • Participants must exhibit a stable seizure baseline for at least 4 weeks prior to enrollment, with documented frequency of two or more drop seizures per week, characterized as generalized tonic-clonic (GTC), secondary GTC (focal to bilateral tonic-clonic seizures), tonic, atonic, or combined tonic-atonic seizures.
  • Participants must exhibit abnormal cognitive development and a medical history consistent with electroencephalographic (EEG) findings demonstrating abnormal background activity characterized by a slow spike-andwave pattern at a frequency of less than 2.5 Hz.
  • Participants must have a clearly documented etiology of LGS falling into one of the following categories: structural, genetic, metabolic, infectious, immune or unknown.
  • Participants must have had a valid baseline EEG that reflects their clinical state during a stable seizure period and must have been conducted within 6 months prior to study enrollment.
  • Participants must be currently receiving fenfluramine as part of their clinical management regimen. Fenfluramine dosing must follow established LGS-specific dosing guidelines, initiated at 0.1 mg/kg administered orally twice daily, with weekly dose titration based on tolerability and clinical response until reaching the recommended maintenance dose of 0.35 mg/kg orally twice daily, not exceeding a total daily dose of 26 mg.
  • At the time of enrollment, participants must have been on a stable antiseizure medication (ASM) regimen for at least 30 days, defined as receiving between one and four concomitant ASMs without any recent medication changes, aside from the addition of fenfluramine. To ensure accurate baseline EEG assessments, participants must have a documented EEG recorded within 6 months (±2 months) prior to initiation of fenfluramine treatment.
  • Caregivers or legal guardians must provide informed consent, and participant assent will be obtained when developmentally appropriate according to ethical standards.

Exclusion Criteria:

  • Patients have been diagnosed with any progressive neurodegenerative disorders, as these conditions could confound the interpretation of fenfluramine's clinical efficacy and safety profile.
  • Individuals with a documented history of fenfluramine use prior to obtaining baseline EEG will be excluded to ensure the baseline EEG data accurately represent the pre-treatment neurophysiological state.
  • Participants who have incomplete medical records, inadequate EEG documentation, or insufficient diagnostic workup confirming LGS diagnosis.

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

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Number of participants who have concordance between electroencephalogram (EEG) changes and clinical responsiveness in patients diagnosed with Lennox-Gastaut Syndrome (LGS) undergoing treatment with fenfluramine after 6 months.
Time Frame: from EEG prior to fenfluarmine initiation to follow up EEG 6 months after
from EEG prior to fenfluarmine initiation to follow up EEG 6 months after

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Time Frame
Number of participants whose specific EEG biomarkers are predicative of clinical responsiveness to fenfluramine treatment before, during, and after fenfluramine treatment
Time Frame: from EEG prior to fenfluarmine initiation to follow up EEG 6 months after
from EEG prior to fenfluarmine initiation to follow up EEG 6 months after
Change from baseline differences of longitudinal EEG dynamics before and during fenfluramine therapy, including changes in background activity, paroxysmal fast activity, epileptiform discharges, and sleep architecture.
Time Frame: from EEG prior to fenfluarmine initiation to follow up EEG 6 months after
from EEG prior to fenfluarmine initiation to follow up EEG 6 months after
Number of clinical responders and non-responders to fenfluramine treatment measured by differences in quantitative EEG variables after 6 months
Time Frame: from EEG prior to fenfluramine initiation to follow up EEG 6 months after
from EEG prior to fenfluramine initiation to follow up EEG 6 months after
Change from baseline in quality of life scores on the Ped-QL epilepsy or QL-Epilepsy after 6 months
Time Frame: from prior to EEG initiation to 6 months after
from prior to EEG initiation to 6 months after

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Chicago

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
UCB Pharma

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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
May 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
April 1, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
April 21, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 21, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
April 29, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 6, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 4, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • IRB25-1092

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

This study will be conducted at a single site and data sharing is not necessary.

Drug and device information, study documents

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.

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