EEG Dynamics in Lennox-Gastaut Syndrome Patients Undergoing Fenfluramine Treatment

NCT07555171 | Enrolling By Invitation

• 1 other identifier: IRB25-1092
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

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).

Conditions

Lennox Gastaut Syndrome (LGS)

Keywords

Lennox Gastaut Syndrome (LGS); fenfluramine

Outcome Measures

Primary Outcomes (1)

• To evaluate the concordance between electroencephalogram (EEG) changes and clinical responsiveness in patients diagnosed with Lennox-Gastaut Syndrome (LGS) undergoing treatment with fenfluramine.

  from EEG prior to fenfluarmine initiation to follow up EEG 6 months after

Secondary Outcomes (4)

• To identify and validate specific EEG biomarkers predictive of clinical responsiveness to fenfluramine treatment.

  from EEG prior to fenfluarmine initiation to follow up EEG 6 months after

• To quantitatively assess longitudinal EEG dynamics, including changes in background activity, paroxysmal fast activity, epileptiform discharges, and sleep architecture, before and during fenfluramine therapy.

  from EEG prior to fenfluarmine initiation to follow up EEG 6 months after

• To characterize EEG biomarker differences between clinical responders and non- responders to fenfluramine.

  from EEG prior to fenfluramine initiation to follow up EEG 6 months after

• To evaluate patient- and caregiver-reported changes in epilepsy-specific quality of life associated with fenfluramine treatment using validated instruments.

  from prior to EEG initiation to 6 months after

Interventions

fenfluramine HCl DRUG

Patients who receive fenfluramine will be enrolled in this non-interventional study.

Eligibility Criteria

• Age: 2 Years - 35 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

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

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• University of Chicago: lead
• UCB Pharma: collaborator

Study Sites (1)

University of Chicago

Chicago, Illinois, 60637, United States

Location

MeSH Terms

Conditions

Lennox Gastaut Syndrome

Interventions

Fenfluramine

Condition Hierarchy (Ancestors)

Epileptic Syndromes; Epilepsy; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Intervention Hierarchy (Ancestors)

Phenethylamines; Ethylamines; Amines; Organic Chemicals

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 21, 2026
• First Posted: April 29, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): April 1, 2028
• Last Updated: April 29, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)