EEG Dynamics in Lennox-Gastaut Syndrome Patients Undergoing Fenfluramine Treatment

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…