An Efficacy and Safety Study of Clemizole HCl in Patients With Lennox-Gastaut Syndrome
Multicenter, Randomized, Double-blind, Placebo-controlled Trial of Clemizole HCl as Adjunctive Therapy in Patients With Lennox-Gastaut Syndrome
1 other identifier
interventional
260
1 country
20
Brief Summary
This is a multicenter, Phase 3, randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of clemizole HCL (EPX-100) as adjunctive therapy in children and adult participants with Lennox-Gastaut syndrome (LGS).
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for phase_3
Started Apr 2025
Longer than P75 for phase_3
20 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
September 23, 2021
CompletedFirst Posted
Study publicly available on registry
October 4, 2021
CompletedStudy Start
First participant enrolled
April 9, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
November 1, 2026
ExpectedStudy Completion
Last participant's last visit for all outcomes
November 1, 2029
April 15, 2026
April 1, 2026
1.6 years
September 23, 2021
April 13, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Percent Change in CMMS-28
Percent change in CMMS-28 from the Baseline Period through the end of the DB Period
From Baseline Period up to 16 weeks
Secondary Outcomes (10)
Proportion of Participants with ≥50% Reduction in CMMS-28
From Baseline Period up to 16 weeks
Percent Change in CMMS-28 Seizure-free Days
From Baseline Period up to 16 weeks
Clinical Global Impression of Change (CGI-C) Score
Week 16
Caregiver Global Impression of Change (CaGI-C) Score
Week 16
Caregiver Global Impression of Change in Seizure Intensity/Duration (CaGI-CSID) Score
Week 16
- +5 more secondary outcomes
Study Arms (3)
Placebo
PLACEBO COMPARATORParticipants will receive their first dose of study drug following randomization.
Double-blind clemizole HCl
EXPERIMENTALParticipants will receive their first dose of study drug following randomization.
Open-label clemizole HCl
EXPERIMENTALEligible participants who complete the DB Period will have the option to continue in the OLE Period, during which they will receive clemizole HCl for up to 3 years.
Interventions
Clemizole HCl will be administered as an oral solution.
Eligibility Criteria
You may qualify if:
- Males or females, ages ≥2 to ≤55 years, at the time of Screening.
- Participant/parent/legal authorized representative (LAR) willing and able to give written informed consent/assent.
- Diagnosis of LGS, including:
- Evidence of at least one type of countable major motor seizure.
- History of electroencephalogram (EEG) consistent with LGS (abnormal background activity, and one of the following: 1) slow spike-wave discharges \[\<2.5 Hz\], or 2) paroxysmal fast activity during sleep).
- Abnormal cognitive development.
- Onset of seizures at 11 years of age or younger.
You may not qualify if:
- Known sensitivity, allergy, or previous exposure to clemizole HCl.
- Known history of long QT syndrome or any significant history of a serious abnormality of the electrocardiogram (ECG) (e.g., recent myocardial infarction, clinically significant arrhythmia).
- Family history of sudden cardiac death, unexplained death, or death from a primary dysrhythmia potentially associated with QT prolongation in any family member.
- Seizures secondary to illicit drug or alcohol use, infection, neoplasm, demyelinating disease, degenerative neurological disease, or progressive central nervous system disease, metabolic illness, recent anoxic episode within the last 6 months requiring resuscitation, or progressive degenerative disease or any other condition, which in the opinion of the investigator, could affect seizure control.
- Epilepsy surgery planned during the study or epilepsy surgery within 6 months prior to Screening.
- Concomitant use of fenfluramine.
- Prior or concomitant use of lorcaserin.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Epygenixlead
- Harmony Biosciences Management, Inc.collaborator
Study Sites (20)
Arkansas Children's Hospital
Little Rock, Arkansas, 72202, United States
UC Irvine Medical Center
Orange, California, 92868, United States
UCI Center for Innovative Health Therapies
Orange, California, 92868, United States
Nemours Children's Health
Wilmington, Delaware, 19803, United States
Rare Disease Research
Kissimmee, Florida, 34746, United States
University of Miami Miller School of Medicine
Miami, Florida, 33136, United States
Pediatric Neurology and Epilepsy Specialists
Winter Park, Florida, 32789, United States
Re:Cognition Health
Chicago, Illinois, 60611, United States
Norton Children's Medical Center
Louisville, Kentucky, 40202, United States
Henry Ford Hospital
Detroit, Michigan, 48202, United States
Minnesota Epilepsy Group, P.A.
Roseville, Minnesota, 55102, United States
Children's Nebraska
Omaha, Nebraska, 68114, United States
Neurology Center for Epilepsy and Seizures
Marlboro, New Jersey, 07746, United States
Tekton Research
Marlboro, New Jersey, 07746, United States
Weill Cornell Medicine/New York Presbyterian Hospital
New York, New York, 10021, United States
Atrium Health STRIVE Research
Charlotte, North Carolina, 28207, United States
On-Site Clinical Solution
Charlotte, North Carolina, 28211, United States
Duke University Medical Center
Durham, North Carolina, 27705, United States
PPD Virtual-Science 37, Inc.
Morrisville, North Carolina, 27560, United States
UTHealth Houston
Houston, Texas, 77030, United States
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Amit Ray, MD
Harmony Biosciences Management, Inc.
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- TRIPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
September 23, 2021
First Posted
October 4, 2021
Study Start
April 9, 2025
Primary Completion (Estimated)
November 1, 2026
Study Completion (Estimated)
November 1, 2029
Last Updated
April 15, 2026
Record last verified: 2026-04
Data Sharing
- IPD Sharing
- Will not share