A Phase 3, Placebo-Controlled Study to Investigate LP352 in Children and Adults With Dravet Syndrome (DS)

Phase 3

Recruiting

• Conditions: Dravet Syndrome
• Interventions: Drug: LP352; Drug: Placebo

• Registration Number: NCT06660394
• Lead Sponsor: Longboard Pharmaceuticals

Brief Summary

This (DEEp SEA 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 DS. The study consists of 3 main phases: Screening, Titration period, and Maintenance period, followed by a Taper period and Follow-Up. Participants will be randomized to LP352 or placebo. The total duration of the study will be approximately 24 months.

Detailed Description

Not available

Study Timeline

• Study Start: 2024-10-02
• Study First Submitted: 2024-10-24
• Study First Submitted QC: 2024-10-24
• Study First Posted: 2024-10-28
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-08
• Last Update Posted: 2025-05-13
• Primary Completion: 2026-09
• Study Completion: 2026-10

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 160

Inclusion Criteria

• Diagnosis of DS must fulfill all of the following criteria:

  1. Participants with seizure onset age >1 and <20 months
  2. The participant has a history of at least 1 of the following seizure type(s): prolonged generalized tonic-clonic, hemiclonic, myoclonic, tonic, atonic, atypical absence, focal impaired awareness, nonconvulsive status epilepticus

• The participant has a current occurrence of at least 1 of the following countable motor seizure types: generalized tonic-clonic, tonic (bilateral), clonic (bilateral), atonic (bilateral) with truncal/leg involvement, focal motor (including hemiclonic), and focal to bilateral tonic-clonic

• The participant has demonstrated an average of at least 4 countable motor seizures per month for the 3 months prior to Screening.

• The participant has been taking 1 to 4 antiseizure medications (ASMs) at a stable dose for at least 4 weeks prior to Screening.

• The participant, parent, or caregiver is willing and able (in the judgment of the investigator) to comply with completion of the diaries throughout the study.

• The participant must be willing and able to provide written informed consent.

Exclusion Criteria

• The participant has a history of infantile/epileptic spasms.
• The participant has been admitted to a medical facility for treatment of status epilepticus requiring mechanical ventilation within 3 months prior to Screening.
• The participant has a neurodegenerative disorder as indicated by magnetic resonance imaging or genetic testing.
• The participant has an acquired lesion/injury unrelated to the primary etiology that could contribute as a secondary cause of seizures.
• The participant is receiving exclusionary medications.
• The participant has used any cannabis product or cannabidiol that is not in oral solution/capsule/tablet form, not obtained from a government-approved dispensary, or contains ≥50% Delta-9-tetrahydrocannabinol (THC).
• The participant has unstable, clinically significant neurologic (other than the disease being studied, eg, recurrent strokes), psychiatric, cardiovascular (eg, pulmonary arterial hypertension, cardiac valvulopathy, orthostatic hypotension/tachycardia), pulmonary, hepatic, renal, metabolic, gastrointestinal, urologic, immunologic, hematopoietic, or endocrine disease or other abnormality which may impact the ability of the participant to participate or potentially confound the study results.
• The participant is unwilling to comply with any of the study requirements or timelines.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
LP352	LP352	Participants will be titrated up to highest tolerated dose of LP352 during the Titration period (Visit 2 - Visit 5), followed by maintenance period (Visit 5 - Visit 8) and then taper/down titration period.
Placebo	Placebo	Placebo for LP352

Primary Outcome Measures

Name	Time	Method
Frequency Percent Change in Countable Motor Seizures During Treatment Compared to Baseline	Baseline and up to 15 Weeks	The percent change from Baseline in countable motor seizure frequency during Treatment will be calculated as countable motor seizure frequency during Treatment minus countable motor seizure frequency during Screening and divided by seizure frequency during Screening and multiplied by 100 where each seizure frequency will be based on number of seizures.

Secondary Outcome Measures

Name	Time	Method
Safety and Tolerability of LP352	Up to 21 Weeks	Safety and tolerability as measured by incidence and severity of non-serious Treatment Emergent Adverse Events (TEAEs), Serious Adverse events (SAEs), AEs leading to discontinuation and clinically significant changes in laboratory parameters (hematology, serum chemistry and Urinalysis), physical examination findings, vital signs, growth parameters (height and weight), 12-lead electrocardiograms (ECGs), C-SSRS responses, and PHQ-9 total score and Question 9 score.
Percentage of participants with ≥ 50% Reduction in countable motor seizures during Treatment compared to Baseline	Baseline and up to 15 Weeks
Frequency Percent Change in Countable Motor Seizures during Maintenance compared to Baseline	Baseline and up to 15 Weeks

Trial Locations

Locations (92)

Site Number - ITA08; 🇮🇹 Verona, Italy

Site Number - FRA08; 🇫🇷 Bron, France

Site Number - FRA04; 🇫🇷 Lille, France

Site Number - DEU07; 🇩🇪 Bonn, Germany

Site Number - LAV01; 🇱🇻 Riga, Latvia

Site Number - CHN01; 🇨🇳 Beijing, China

Site Number - DEU01; 🇩🇪 Frankfurt, Germany

Site Number - DEU04; 🇩🇪 Freiburg im Breisgau, Germany

Site Number - MEX01; 🇲🇽 Mexico City, Cdmx, Mexico

Site Number - MEX02; 🇲🇽 Mexico City, Cdmx, Mexico

Site Number - NLD02; 🇳🇱 Zwolle, BV, Netherlands

Site Number - FRA06; 🇫🇷 Marseille, France

Site Number - FRA09; 🇫🇷 Paris, France

Site Number - DEU03; 🇩🇪 Kiel, Germany

Site Number - DEU06; 🇩🇪 Radeberg, Germany

Site Number - DEU05; 🇩🇪 Ravensburg, Germany

Site Number - ITA03; 🇮🇹 Genova, Italy

Site Number - PRT02; 🇵🇹 Coimbra, Portugal

Site Number - PRT03; 🇵🇹 Lisbon, Portugal

Site Number - PRT05; 🇵🇹 Porto Covo, Portugal

Site Number - GBRXX; 🇬🇧 London, United Kingdom

Site Number - GBR03; 🇬🇧 London, United Kingdom

Site Number - GBR05; 🇬🇧 Newcastle Upon Tyne, United Kingdom

Site Number - GBR02; 🇬🇧 Southampton, United Kingdom

Site Number - BRA02; 🇧🇷 Ribeirão Preto, SP, Brazil

Site Number - BRA05; 🇧🇷 São José Do Rio Preto, SP, Brazil

Site Number - BRA03; 🇧🇷 São Paulo, SP, Brazil

Site Number - BRA01; 🇧🇷 Curitiba, Brazil

Site Number - FRA05; 🇫🇷 Paris, France

Site Number - FRA01; 🇫🇷 Rennes, France

Site Number - CAN04; 🇨🇦 Vancouver, British Columbia, Canada

Site Number - FRA07; 🇫🇷 Strasbourg, France

Site Number - ITA02; 🇮🇹 Pavia, Italy

Site Number SRB 06; 🇷🇸 Belgrade, Serbia

Site Number - SRB02; 🇷🇸 Belgrade, Serbia

Site Number - SRB03; 🇷🇸 Kragujevac, Serbia

Site Number - CAN01; 🇨🇦 Toronto, Ontario, Canada

Site Number - FRA03; 🇫🇷 Toulouse, France

Site Number - ITA06; 🇮🇹 Roma, Italy

Site Number - ITA01; 🇮🇹 Roma, Italy

Site Number - ESP05; 🇪🇸 Barcelona, Spain

Site Number - ESP12; 🇪🇸 Barcelona, Spain

Site Number - ESP02; 🇪🇸 Barcelona, Spain

Site Number - ESP011; 🇪🇸 Madrid, Spain

Site Number - ESP03; 🇪🇸 Madrid, Spain

Site Number - ESP04; 🇪🇸 Málaga, Spain

Site Number - ESP09; 🇪🇸 Málaga, Spain

Site Number - ESP06; 🇪🇸 Pamplona, Spain

Site Number - ESP08; 🇪🇸 Valencia, Spain

Site Number - GBR04; 🇬🇧 Glasgow, United Kingdom

Site Number - USA19; 🇺🇸 Little Rock, Arkansas, United States

Site Number - USA29; 🇺🇸 La Jolla, California, United States

Site Number - USA26; 🇺🇸 Los Angeles, California, United States

Site Number - USA18; 🇺🇸 Los Angeles, California, United States

Site Number - USA24; 🇺🇸 Palo Alto, California, United States

Site Number - USA28; 🇺🇸 San Francisco, California, United States

Site Number - USA17; 🇺🇸 Aurora, Colorado, United States

Site Number - USA02; 🇺🇸 Gulf Breeze, Florida, United States

Site Number - USA37; 🇺🇸 Miami, Florida, United States

Site Number - USA05; 🇺🇸 Orlando, Florida, United States

Site Number - USA11; 🇺🇸 Tampa, Florida, United States

Site Number - USA09; 🇺🇸 Atlanta, Georgia, United States

Site Number - USA38; 🇺🇸 Chicago, Illinois, United States

Site Number - USA07; 🇺🇸 Bethesda, Maryland, United States

Site Number - USA40; 🇺🇸 Boston, Massachusetts, United States

Site Number - USA15; 🇺🇸 Rochester, Minnesota, United States

Site Number - USA10; 🇺🇸 Livingston, New Jersey, United States

Site Number - USA36; 🇺🇸 Morristown, New Jersey, United States

Site Number - USA32; 🇺🇸 New York, New York, United States

Site Number - USA14; 🇺🇸 Cincinnati, Ohio, United States

Site Number - USA39; 🇺🇸 Cleveland, Ohio, United States

Site Number - DEU02; 🇩🇪 Bielefeld, Germany

Site Number - USA35; 🇺🇸 Columbus, Ohio, United States

Site Number - USA33; 🇺🇸 Portland, Oregon, United States

Site Number - USA22; 🇺🇸 Charleston, South Carolina, United States

Site Number - USA34; 🇺🇸 Memphis, Tennessee, United States

Site Number - USA41; 🇺🇸 Austin, Texas, United States

Site Number - USA31; 🇺🇸 Fort Worth, Texas, United States

Site Number - USA25; 🇺🇸 Houston, Texas, United States

Site Number - USA03; 🇺🇸 Tacoma, Washington, United States

Site Number - AUS07; 🇦🇺 Randwick, New South Wales, Australia

Site Number - AUS08; 🇦🇺 Randwick, New South Wales, Australia

Site Number - AUS09; 🇦🇺 Westmead, New South Wales, Australia

Site Number - AUS04; 🇦🇺 Herston, Queensland, Australia

Site Number - AUS05; 🇦🇺 South Brisbane, Queensland, Australia

Site Number - AUS02; 🇦🇺 Heidelberg, Victoria, Australia

Site Number - AUS03; 🇦🇺 Melbourne, Victoria, Australia

Site Number - AUS06; 🇦🇺 Parkville, Victoria, Australia

Site Number - BEL01; 🇧🇪 Edegem, Belgium

Site Number - BEL02; 🇧🇪 Leuven, Belgium

Site Number - CAN03; 🇨🇦 Toronto, Ontario, Canada

Site Number - ITA04; 🇮🇹 Toscana, Italy