Developmental and Epileptic Encephalopathy (DEE)

Developmental and epileptic encephalopathy (DEE) is a group of severe neurological disorders in which both epilepsy and abnormal brain development contribute to cognitive and developmental impairments. DEE is typically a lifelong condition with significant impact on quality of life and development, requiring comprehensive, multidisciplinary care.

  • Cause: Often due to genetic mutations (e.g., SCN1A, KCNQ2, CDKL5, etc.), though structural brain abnormalities or metabolic disorders can also be involved.

  • Features: Early-onset, hard-to-control seizures, along with developmental delays, intellectual disability, and sometimes regression of skills.

  • Diagnosis: Based on clinical history, EEG findings, brain imaging, and genetic testing.

  • Treatment: Includes anti-seizure medications, ketogenic diet, therapies (physical, occupational, speech), and in some cases, gene-targeted treatments.

Active Trials

  • TITLE: A 20-Week Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial of EPX-100 (Clemizole Hydrochloride) as Adjunctive Therapy in Children and Adult Participants With Dravet Syndrome (ARGUS Trial)

    SPONSOR: Epygenix

    INDICATION: Dravet Syndrome

    STUDY PROTOCOL: EPX-100-001

    PHASE: 3

    DESCRIPTION: This is a global multicenter, randomized, double-blind, placebo-controlled study to evaluate the safety and efficacy of clemizole HCl as adjunctive therapy in children and adult participants with Dravet syndrome. The study consists of a 4-week Observational Period, a 16-week Double-Blind (DB) Period and an Open-Label Extension (OLE) Period for up to 156 weeks.

    STATUS: Upcoming

    RECRUITING PATIENTS: Not yet recruiting

    RDR LOCATION: Florida

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  • TITLE: Multicenter, Randomized, Double-blind, Placebo-controlled Trial of Clemizole HCl as Adjunctive Therapy in Patients With Lennox-Gastaut Syndrome

    SPONSOR: Epygenix

    INDICATION: Lennox-Gastaut Syndrome

    STUDY PROTOCOL: EPX-100-003

    PHASE: 3

    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.

    STATUS: Upcoming

    RECRUITING PATIENTS: Not yet recruiting

    RDR LOCATION: Florida

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  • TITLE: A Phase 2, Prospective, Interventional, Open-Label, Multisite, Extension Study To Assess the Long-Term Safety and Tolerability of Soticlestat (TAK-935) as Adjunctive Therapy in Subjects With Developmental Epileptic Encephalopathies Including Dravet Syndrome, Lennox Gastaut Syndrome, CDKL5 Deficiency Disorder, and Chromosome 15 Duplication Syndrome.

    SPONSOR: Takeda Development Center Americas, Inc.

    INDICATION: Developmental Epileptic Encephalopathies including Dravet Syndrome (DS), Lennox-Gastaut Syndrome (LGS), CDKL5 Deficiency Disorder, and Chromosome 15 Duplication Syndrome.

    STUDY PROTOCOL: TAK-935-18-001

    PHASE: 2

    DESCRIPTION: This is a multisite, open-label extension (OLE) study designed to obtain additional safety and tolerability data related to soticlestat (also known as TAK-935) administered long-term in subjects with developmental and epileptic encephalopathies who participated in a previous soticlestat clinical study. Additional aims are to explore the long-term effects of soticlestat on seizure frequency and to assess the effects of soticlestat on quality-of-life measures. Participants will receive soticlestat twice a day. Participants will visit the study clinic every 2-6 months throughout the study.

    Study treatments may continue as long as the participant is receiving benefit from it.

    STATUS: Active

    RECRUITING PATIENTS: No

    RDR LOCATION: Georgia

Past Trials

  • TITLE: A Phase 3, Placebo-controlled study to investigate LP352 in children and adults with Developmental and Epileptic Encephalopathies

    SPONSOR: Longboard Pharmaceuticals, Inc.

    INDICATION: Developmental and Epileptic Encephalopathy

    PROTOCOL: LP352-301

    PHASE: 3

    DESCRIPTION: This (DEEp OCEAN Study) is a double-blind, randomized, placebo-controlled, multicenter study to investigate the efficacy, safety, and tolerability of LP352 in the treatment of seizures in children and adults with DEE. The study consists of 3 main phases: Screening, Titration period, Maintenance period, followed by a Taper period and Follow-Up. The total duration of the study will be approximately 24 months.

    STATUS: Active

    RECRUITING PATIENTS: No

    RDR LOCATION: Georgia

  • TITLE: A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study to Investigate the Efficacy, Safety, and Tolerability of LP352 in the Treatment of Seizures in Children and Adults with Dravet Syndrome

    SPONSOR: Longboard Pharmaceuticals, Inc.

    INDICATION: Dravet Syndrome

    PROTOCOL: LP352-302

    PHASE: 3

    DESCRIPTION: LP352-302 is a Phase 3 study being conducted to determine if LP352 (bexicaserin) is an effective and safe treatment for seizures in children and adults with DS, a subtype of developmental and epileptic encephalopathy (DEE). In support of this clinical trial, Longboard Pharmaceuticals, Inc. (Longboard) has completed a Phase 1b/2a study (LP352-201) of LP352 in participants with DEE (including DS).

    STATUS: Active

    RECRUITING PATIENTS: No

    RDR LOCATION: Georgia

  • TITLE: A Phase 2, Double-Blind, Randomized Clinical Trial to Explore the Safety, Tolerability, Efficacy, and Pharmacokinetics of PRAX-562 in Pediatric Participants with Developmental and Epileptic Encephalopathies Followed by an Open-Label Extension.

    SPONSOR: Praxis Precision Medicines

    INDICATION: Developmental Epileptic Encephalopathies

    STUDY PROTOCOL: PRAX-562-221

    PHASE: 2

    DESCRIPTION: PRAX-562-221 is a Phase 2, multicenter, double-blind, randomized clinical trial, followed by an open-label extension (OLE), and is designed to explore the safety, tolerability, efficacy, and PK of PRAX-562 when administered to pediatric participants who have seizures associated with early-onset SCN2A-DEE and SCN8A-DEE.

    STATUS: Active

    RECRUITING PATIENTS: No

    RDR LOCATION: Georgia

  • TRIAL TITLE: A Prospective, Remote Observational Study in Pediatric Participants With Early-Onset SCN2A-Developmental and Epileptic Encephalopathy

    SPONSOR: Praxis Precision Medicines

    INDICATION: SCN2A-Developmental and Epileptic Encephalopathy

    PROTOCOL: SCN2A-NH1

    PHASE: Observational

    DESCRIPTION: This prospective observational study is designed to assess the individualized baseline disease burden in pediatric participants aged 1 year to 16 years, with early-onset SCN2A-DEE by characterizing and quantifying changes in clinical features over a period of up to 12 months.

    STATUS: Completed

    RECRUITING PATIENTS: No

    RDR LOCATION: Georgia