An Efficacy and Safety Study of Clemizole HCl in Patients With Lennox-Gastaut Syndrome

Phase 3

Recruiting

• Conditions: Lennox Gastaut Syndrome
• Interventions: Drug: Placebo; Drug: Clemizole HCl

• Registration Number: NCT05066217
• Lead Sponsor: Epygenix

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).

Detailed Description

This is a multicenter, Phase 3, randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of clemizole HCl as adjunctive therapy in children and adult participants with LGS.

The study will consist of an Observational Period, a Double-Blind (DB) Period, and an optional Open-Label Extension (OLE) Period.

Study Timeline

• Study First Submitted: 2021-09-23
• Study First Submitted QC: 2021-09-23
• Study First Posted: 2021-10-04
• Status Verified: 2025-04
• Study Start: 2025-04-08
• Last Update Submitted: 2025-04-08
• Last Update Posted: 2025-04-10
• Primary Completion: 2026-11-01
• Study Completion: 2029-11-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 260

Inclusion Criteria

1. Males or females, ages ≥2 to ≤55 years, at the time of Screening.

2. Participant/parent/legal authorized representative (LAR) willing and able to give written informed consent/assent.

3. 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.

Key

Exclusion Criteria

1. Known sensitivity, allergy, or previous exposure to clemizole HCl.
2. 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).
3. Family history of sudden cardiac death, unexplained death, or death from a primary dysrhythmia potentially associated with QT prolongation in any family member.
4. 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.
5. Epilepsy surgery planned during the study or epilepsy surgery within 6 months prior to Screening.
6. Concomitant use of fenfluramine.
7. Prior or concomitant use of lorcaserin.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Participants will receive their first dose of study drug following randomization.
Double-blind clemizole HCl	Clemizole HCl	Participants will receive their first dose of study drug following randomization.
Open-label clemizole HCl	Clemizole HCl	Eligible 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.
Open-label clemizole HCl	Placebo	Eligible 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.

Primary Outcome Measures

Name	Time	Method
Percent Change in CMMS-28	From Baseline Period up to 16 weeks	Percent change in CMMS-28 from the Baseline Period through the end of the DB Period

Secondary Outcome Measures

Name	Time	Method
Proportion of Participants with ≥50% Reduction in CMMS-28	From Baseline Period up to 12 weeks	Proportion of participants with ≥50% reduction in CMMS-28 from the Baseline Period through the end of the DB Maintenance Phase only
Percent Change in CMMS-28 Seizure-free Days	From Baseline Period up to 16 weeks	Percent change in CMMS-28 seizure-free days from the Baseline Period through the end of the DB Period
Clinical Global Impression of Change (CGI-C) Score	Week 16	CGI-C score at the end of the DB Period
Caregiver Global Impression of Change (CaGI-C) Score	Week 16	CaGI-C score at the end of the DB Period
Caregiver Global Impression of Change in Seizure Intensity/Duration (CaGI-CSID) Score	Week 16	CaGI-CSID score at the end of the DB Period
Change in Quality of Life Inventory (QI)-Disability Score	From Baseline Period up to 16 weeks	Change in QI-disability score from Baseline to the end of the DB Period
Percent Change per 28 Days in the Number of Seizure Free Days	From Baseline Period up to 16 weeks	Percent change per 28 days in the number of seizure-free days (based on all seizure types) from the Baseline Period through the end of the DB Period
Percent Change in CMMS-28	From Baseline Period up to 12 weeks	Percent change in CMMS-28 from the Baseline Period through the end of the DB Maintenance Phase only
Incidence of Treatment-Emergent Adverse Events (TEAEs)	From the first dose administration of study drug up to end of the study, approximately up to 172 weeks	Incidence of TEAEs will be compared among the treatment groups

Trial Locations

Locations (2)

Rare Disease Research; 🇺🇸 Kissimmee, Florida, United States

On-Site Clinical Solution; 🇺🇸 Raleigh, North Carolina, United States