AzTrials
AzTrials

Dravet SyndromePhase 3NCT06660394

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

A Phase 3 study testing LP352 in people with Dravet Syndrome, run by Longboard Pharmaceuticals at 105 sites in 18 countries.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record
Search all trials

Trial 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. Read more about this study

Who is it for?
Ages 2 to 65 years
Conditions the study is for
Dravet Syndrome
What is being tested?
LP352
Type of treatment
Pill or oral medicine
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
108 participants
Where
105 sitesin 18 countries
Study dates
25 Sep 2024to 31 Dec 2026
Phase
Phase 3
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 2 to 65 years
  • All sexes
  • No healthy volunteers
  • Child, Adult, Older adult

Who may be able to join

  • Diagnosis of DS must fulfill all of the following criteria:
  • Participants with seizure onset age >1 and <20 months
  • 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.

Who cannot join

  • 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 is currently using 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.

Trial locations and contacts

105 sites in 18 countries.

105 sites in 18 countries

United States25 sites

  • Rare Disease Research, LLC. (RDR)

    Atlanta, Georgia, 30329

  • Children's Hospital Colorado - Heart Institute

    Aurora, Colorado, 80045-7106

  • Child Neurology Consultants of Austin - Austin

    Austin, Texas, 78731-3157

  • Mid-Atlantic Epilepsy and Sleep Center - Bethesda

    Bethesda, Maryland, 20817-1844

  • Northwestern Memorial Hospital

    Chicago, Illinois, 60611-2908

  • Northwestern University - Ann & Robert H. Lurie Children's Hospital of Chicago - Center for Cance...

    Chicago, Illinois, 60611-2991

  • Cook Children's Jane and John Justin Neurosciences Center

    Fort Worth, Texas, 76104-2710

  • NW FL Clinical Research Group, LLC

    Gulf Breeze, Florida, 32561-4495

  • The University of Texas Medical School at Houston - UT Gastroenterology

    Houston, Texas, 77030-1517

  • Arkansas Children's Hospital - Cardiology Clinic

    Little Rock, Arkansas, 72202-3500

  • Barnabas Health - Institute of Neurology and Neurosurgery

    Livingston, New Jersey, 07039-5817

  • Children's Hospital Los Angeles (CHLA)

    Los Angeles, California, 90027-6062

  • University of California Los Angeles (UCLA) - David Geffen School of Medicine - Global Health Pro...

    Los Angeles, California, 90095

  • Le Bonheur Children's Hospital - Outpatient Center

    Memphis, Tennessee, 38105-4625

  • Nicklaus Children's Hospital (Miami Children's Hospital)

    Miami, Florida, 33155-3009

  • Northeast Regional Epilepsy Group - Morristown

    Morristown, New Jersey, 07960-6092

  • NYU Langone Health-NYU Comprehensive Epilepsy Center

    New York, New York, 10016-4852

  • Research Institute of Orlando LLC

    Orlando, Florida, 32806

  • Stanford University - Stanford School of Medicine - Pulmonary and Cystic Fibrosis Center

    Palo Alto, California, 94304-1511

  • Oregon Health & Science University - Blood Brain Barrier and Neuro-Oncology Program

    Portland, Oregon, 97239-3098

  • Mayo Clinic - Children's Center - Rochester

    Rochester, Minnesota, 55905-0001

  • UCSF Benioff Children's Hospitals - San Francisco

    San Francisco, California, 94158

  • MultiCare Health System

    Tacoma, Washington, 98415-0299

  • Pediatric Epilepsy & Neurology Specialists (PENS)

    Tampa, Florida, 33609-4191

  • Children's National Hospital - Children's National Heart Center

    Washington D.C., District of Columbia, 20010-2916

Other trials in United States

Japan10 sites

  • Fukuoka Children's Hospital (FCH)

    Fukuoka, Fukuoka, 813-0017

  • National Center of Neurology and Psychiatry-National Center Hospital

    Kodaira-shi, Tokyo-To, 187-8551

  • Dokkyo Medical University Hospital

    Mibu-Machi, Tochigi, 321-0293

  • International University of Health and Welfare - Narita Hospital

    Narita-shi, Chiba, 286-8520

  • National Hospital Organization Nishi-Niigata Chuo National Hospital

    Niigata, 950-2074

  • Okayama University Hospital

    Okayama, Okayama-ken, 700-8558

  • Osaka City General Hospital

    Osaka, Osaka, 534-0021

  • Saitama Prefectural Children's Medical Center

    Saitama-shi, Saitama, 330-8777

  • Hokkaido University Hospital

    Sapporo, Hokkaido, 060-8648

  • National Hospital Organization Shizuoka Institute of Epilepsy and Neurological Disorders

    Shizuoka, 420-0953

Other trials in Japan

Australia8 sites

  • Royal Brisbane and Women's Hospital (RBWH)

    Brisbane, Queensland, 4006

  • Queensland Children's Hospital (Lady Cilento Children's Hospital)

    Brisbane, Queensland, 4101

  • Austin Hospital

    Heidelberg, Victoria, 3084

  • The Alfred Hospital

    Melbourne, Victoria, 3004

  • The Royal Children's Hospital (RCH) Melbourne

    Parkville, Victoria, 3052

  • Prince of Wales Hospital (POWH)

    Randwick, New South Wales, 2031

  • Sydney Children's Hospital - Randwick

    Randwick, New South Wales, 2031

  • The Children's Hospital-Westmead - Heart Centre for Children

    Westmead, New South Wales, 2145

Other trials in Australia

France8 sites

  • Hospices Civils de Lyon (HCL) - Hopital Pierre Wertheimer

    Bron, Auvergne-Rhône-Alpes, 69500

  • Hôpital Roger Salengro

    Lille, Nord, 59000

  • AP-HM- Hôpital de La Timone

    Marseille, 13005

  • AP-HP - Hôpital universitaire Necker-Enfants malades

    Paris, 75015

  • AP-HP - Hôpital universitaire Robert-Debré

    Paris, 75019

  • Les Hôpitaux Universitaires de Strasbourg - Hôpital de Hautepierre

    Strasbourg, 67098

  • Centre Hospitalier Universitaire (CHU) de Toulouse - Hopital de Psychiatrie

    Toulouse, Occitanie, 31059

  • Chu de Rennes - Centre d'Evaluation et de Traitement de la Douleur de l'Adulte et de l'Enfant

    Villejuif, Île-de-France Region, 94800

Other trials in France

Spain8 sites

  • Hospital Universitari Vall d'Hebron

    Barcelona, 08035

  • Hospital de la Santa Creu I Sant Pau

    Barcelona, 8041

  • Hospital Sant Joan de Deu Barcelona (HSJDB)

    Esplugues de Llobregat, Barcelona, 08950

  • Hospital Universitario Vithas Madrid La Milagrosa

    Madrid, 28010

  • Hospital Ruber Internacional

    Madrid, 28034

  • Hospital Regional Universitario de Malaga - Hospital General

    Málaga, 29010

  • Hospital Vithas Malaga

    Málaga, 29016

  • Hospital Universitario de Navarra

    Pamplona, Navarre, 31008

Other trials in Spain

Brazil7 sites

  • Universidade Estadual de Campinas (UNICAMP) - Hospital das Clinicas (HC)

    Campinas, São Paulo, 13083-888

  • Instituto de Neurologia de Curitiba (INC)

    Curitiba, Paraná, 81210-310

  • Moinhos de Vento Hospital (Hospital Moinhos de Vento) (HMV)

    Porto Alegre, Rio Grande do Sul, 90035-001

  • Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS) - Instituto Do Cerebro Do Rio Grand...

    Porto Alegre, Rio Grande do Sul, 90610-970

  • Universidade de Sao Paulo (USP)-Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto ...

    Ribeirão Preto, São Paulo, 14051-260

  • Faculdade de Medicina de Sao Jose do Rio Preto-SP (FAMERP)

    São José do Rio Preto, São Paulo, 15090-000

  • Universidade de Sao Paulo (USP) - Hospital das Clinicas da Faculdade de Medicina (HCFMUSP) - Inst...

    São Paulo, 05403-903

Other trials in Brazil

China6 sites

  • Peking University First Hospital (Beida Hospital)

    Beijing, Beijing Municipality, 100034

  • Capital Medical University-Beijing Children's Hospital

    Beijing, Beijing Municipality, 100045

  • Guangzhou Medical University-The Second Affiliated Hospital

    Guangzhou, Guangdong, 510260

  • Fudan University - Children's Hospital

    Shanghai Shi, Shanghai Municipality, 201102

  • Shenzhen Children's Hospital

    Shenzhen Shi, Guangdong, 518026

  • Wuhan Children's Hospital

    Wuhan, Hubei, 430016

Other trials in China

Italy6 sites

  • Azienda Ospedaliero-Universitaria - Ospedale Pediatrico Meyer

    Florence, Florence, 50139

  • Istituto Giannina Gaslini (Ospedale Pediatrico IRCCS) - Centro Malattie Rare

    Genoa, 16147

  • Fondazione Mondino, IRCCS Istituto Neurologico Nazionale a Carattere Scientifico

    Pavia, 27100

  • Ospedale Pediatrico Bambino Gesu - Gianicolo

    Rome, 00165

  • Universita Cattolica del Sacro Cuore - Fondazione Policlinico Universitario A Gemelli - Centro pe...

    Rome, 00168

  • Azienda Ospedaliera Universitaria Integrata Verona - Centro Fibrosi Cistica di Verona (CFC Verona)

    Verona, 37126

Other trials in Italy

Germany5 sites

  • Gesellschaft fuer Epilepsieforschung e.V.

    Bielefeld, North Rhine-Westphalia, 33617

  • Universitätsklinikum Bonn

    Bonn, North Rhine-Westphalia, 53127

  • Universitätsklinikum Frankfurt - Klinikum der Goethe-Universität

    Frankfurt am Main, Hesse, 60596

  • Universitaetsklinikum Schleswig-Holstein (UKSH) - Campus Kiel - Klinik fuer Psychosomatik und Psy...

    Kiel, Schleswig-Holstein, 24105

  • Epilepsie-Zentrum Bodensee

    Ravensburg, 88214

Other trials in Germany

Canada4 sites

  • London Health Sciences Centre (LHSC)

    London, Ontario, N6A 5W9

  • The Hospital for Sick Children (SickKids)

    Toronto, Ontario, M5G 1X8

  • University Health Network-Toronto Western Hospital - Krembil Neuroscience Centre (KNC)

    Toronto, Ontario, M5T 2S8

  • BC Children's Hospital (British Columbia Children's Hospital)

    Vancouver, British Columbia, V6H 3V4

Other trials in Canada

Serbia4 sites

  • Univerzitetski Klinicki Centar Srbije - Klinika za Neurologiju

    Belgrade, Beograd, 11000

  • Institut za Zdravstvenu Zastitu Majke i Deteta Srbije Dr Vukan Cupic

    Belgrade, Beograd, 11070

  • University of Belgrade-Faculty of Medicine - Clinic of Neurology and Psychiatry for Children and ...

    Belgrade, Beograd, 112112

  • Clinical Center Kragujevac

    Kragujevac, Sumadijski Okrug, 34000

Other trials in Serbia

United Kingdom4 sites

  • NHS Greater Glasgow and Clyde-Glasgow Clinical Research Facility - Queen Elizabeth University Hos...

    Glasgow, South Western Scotland, G51 4TF

  • University College London Hospitals NHS Foundation Trust (UCLH)

    London, NW1 2PG

  • Great Ormond Street Hospital for Children NHS Foundation Trust

    London, WC1N 3JH

  • The Newcastle upon Tyne Hospitals NHS Foundation Trust - Royal Victoria Infirmary (RVI)

    Newcastle upon Tyne, North East, NE1 4LP

Other trials in United Kingdom

Portugal3 sites

  • Hospital Pediátrico de Coimbra

    Coimbra, 3000-602

  • Unidade Local de Saude Santa Maria, E.P.E (ULSSM)

    Lisbon, 1649-035

  • Centro Hospitalar Universitario de Santo Antonio - Centro Materno Infantil do Norte (CMIN)

    Porto, 4050

Other trials in Portugal

Belgium2 sites

  • Universitair Ziekenhuis Antwerpen (UZA)

    Edegem, Antwerp, 2650

  • Universitaire Ziekenhuizen Leuven - Campus Gasthuisberg

    Leuven, Flemish Brabant, 3000

Other trials in Belgium

Denmark2 sites

  • Aarhus Universitetshospital

    Aarhus, Central Jutland, 8200

  • Filadelfia - Epilepsihospitalet (Danish Epilepsy Centre)

    Dianalund, Region Sjælland, 4293

Other trials in Denmark

Finland1 site

  • Helsingin Yliopistollinen Keskussairaala (HYKS) - Uusi Lastensairaala

    Helsinki, Uusimaa, 00029

Other trials in Finland

Latvia1 site

  • Bernu Kliniska Universitates Slimnica (BKUS) (University Children's Hospital)

    Riga, LV-1004

Other trials in Latvia

Mexico1 site

  • Instituto Nacional de Pediatria (INP) (National Institute of Pediatrics)

    Mexico City, Mexico City, 04530

Other trials in Mexico

About this study

Official 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

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.

Conditions
Dravet Syndrome
Being tested
LP352, Placebo
Keywords
Antiseizure medication, Epilepsy, Neurodevelopmental disorders, Developmental and epileptic encephalopathy, LP352, Seizures, DEEp SEA, Bexicaserin
Medical subject headings
Epilepsies, Myoclonic, Epilepsy, Neurodevelopmental Disorders, Seizures

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • LP352Drug

    Also called Bexicaserin

    LP352 will be administered orally or through G-tube/ percutaneous endoscopic gastrostomy (PEG) tube

  • PlaceboDrug

    Also called Placebo Comparator

    Participants will be administered with matching placebo orally or through G-tube/ PEG tube

Study groups in NCT06660394
Study groupRoleWhat they receive
LP352ExperimentalParticipants 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.
Receives: Drug: LP352
PlaceboPlacebo comparatorPlacebo for LP352
Receives: Drug: Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Frequency Percent Change in Countable Motor Seizures During Treatment Compared to Baseline

    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.

    Measured: Baseline and up to 15 Weeks

Secondary outcomes (3)

  1. Safety and Tolerability of LP352

    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.

    Measured: Up to 21 Weeks

  2. Percentage of participants with ≥ 50% Reduction in countable motor seizures during Treatment compared to Baseline

    Measured: Baseline and up to 15 Weeks

  3. Frequency Percent Change in Countable Motor Seizures during Maintenance compared to Baseline

    Measured: Baseline and up to 15 Weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted28 Oct 2024
  2. Study start25 Sep 2024
  3. Primary completion31 Dec 2026 (estimated)
  4. Study completion31 Dec 2026 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
108 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06660394
Sponsor's protocol ID
LP352-302
Other IDs
2024-514937-39-00
Status last verified
Oct 2026
First submitted
24 Oct 2024
Last updated
27 Oct 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
Undecided

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing LP352 in people with Dravet Syndrome, run by Longboard Pharmaceuticals at 105 sites in 18 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 8 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: under way, not looking for participants, as of the sponsor's last update on 27 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 105 sites in United States, Japan, Australia, France, Spain and 13 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Frequency Percent Change in Countable Motor Seizures During Treatment Compared to Baseline (time frame: Baseline and up to 15 Weeks). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06660394.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Oct 2026.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in