Developmental and Epileptic EncephalopathyPhase 3NCT06719141
A Study to Investigate LP352 in Children and Adults With Developmental and Epileptic Encephalopathies (DEE)
A Phase 3 study testing LP352 in people with Developmental and Epileptic Encephalopathy, run by Longboard Pharmaceuticals at 116 sites in 17 countries.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 2 to 65 years
- Conditions the study is for
- Developmental and Epileptic Encephalopathy
- 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
- 367 participants
- Where
- 116 sitesin 17 countries
- Study dates
- 11 Nov 2024to 30 Nov 2026
- Phase
- Phase 3
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
- Participants who are characterized as having Lennox-Gastaut Syndrome (LGS) must fulfill all of the following criteria:
- Onset of seizures at ≤8 years old
- History of tonic/tonic-atonic seizures plus at least 1 of the following seizure type(s): atypical absence, atonic, myoclonic, focal impaired awareness, generalized tonic-clonic, nonconvulsive status epilepticus, or epileptic spasms
- Presence of developmental plateauing or regression
- History of electroencephalogram (EEG) showing generalized slow (<2.5 Hertz [Hz]) spike-and-wave complexes
- Participants who are characterized as having DEE (Other) must fulfill all of the following criteria:
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- Does not meet criteria for LGS
- Onset of seizures at ≤5 years old
- Presence of developmental plateauing or regression
- History of multiple seizure types
- History of interictal EEG background showing diffuse or multifocal slowing (with or without epileptiform activity)
- 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 each of 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; in instances where the participant is unable to provide consent, an appropriate legal representative.
Who cannot join
- The participant has a diagnosis of Dravet Syndrome (DS) or has a mutation of the Sodium channel protein type 1 subunit alpha (SCN1A) gene consistent with DS.
- 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 unable or unwilling to comply with any of the study requirements or timelines.
Trial locations and contacts
116 sites in 17 countries.
116 sites in 17 countries
United States31 sites
Children's Healthcare of Atlanta (CHOA)
Atlanta, Georgia, 30329-2311
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
Consultants in Epilepsy & Neurology, PLLC
Boise, Idaho, 83702-5029
Massachusetts General Hospital (MGH)
Boston, Massachusetts, 02114
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
University of Iowa Health Care Medical Center (University of Iowa Hospitals & Clinics)
Iowa City, Iowa, 52242-1009
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
University of Miami Medical Group (UMMG)
Miami, Florida, 33136-2117
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
University of South Florida (USF) - Tampa Campus
Tampa, Florida, 33620
Children's National Hospital - Children's National Heart Center
Washington D.C., District of Columbia, 20010-2916
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
Spain10 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 Infantil Universitario Nino Jesus (HIUNJS)
Madrid, 28009
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
Hospital Universitari i Politecnic La Fe de Valencia (Hospital La Fe Bulevar Sur)
Valencia, 46026
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
France8 sites
Centre Hospitalier Universitaire de Lyon - Hôpital Pierre Wertheimer
Bron, 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
Hôpital de Hautepierre - Les Hôpitaux Universitaires de Strasbourg
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
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
Italy7 sites
Azienda Ospedaliero-Universitaria Meyer - Ospedale dei Bambini
Florence, Tuscany, 50139
Istituto Giannina Gaslini (Ospedale Pediatrico IRCCS) - Centro Malattie Rare
Genoa, 16147
Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta
Milan, 20133
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
United Kingdom7 sites
University Hospitals Birmingham (UHB) NHS Foundation Trust - Queen Elizabeth Hospital Birmingham
Birmingham, West Midlands, B15 2WB
Cardiff and Vale University Health Board - University Hospital of Wales (UHW) - Noah's Ark Childr...
Cardiff, East Wales, CF14 4XW
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
University Hospital Southampton NHS Foundation Trust-Southampton General Hospital (SGH)
Southampton, South East, SO16 6YD
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
Germany6 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
Epilepsiezentrum Kleinwachau gemeinnützige GmbH
Radeberg, Saxony, 01454
Epilepsie-Zentrum Bodensee
Ravensburg, 88214
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
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
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
Belgium2 sites
Universitair Ziekenhuis Antwerpen (UZA)
Edegem, Antwerp, 2650
Universitaire Ziekenhuizen Leuven - Campus Gasthuisberg
Leuven, Flemish Brabant, 3000
Latvia1 site
Bernu Kliniska Universitates Slimnica (BKUS) (University Children's Hospital)
Riga, LV-1004
Mexico1 site
Instituto Nacional de Pediatria (INP) (National Institute of Pediatrics)
Mexico City, Mexico City, 04530
Netherlands1 site
Universitair Medisch Centrum Utrecht - Polikliniek Oogheelkunde
Utrecht, 3584 CX
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 Developmental and Epileptic Encephalopathies
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.
- Being tested
- LP352, Placebo
- Keywords
- Developmental and epileptic encephalopathy, LP352, Seizures, Bexicaserin, Antiseizure medications (ASMs), Epilepsy, Lennox-Gastaut Syndrome (LGS), Neurodevelopmental disorders, DEEp OCEAN
- Medical subject headings
- Seizures, Epilepsy, Lennox Gastaut Syndrome, Neurodevelopmental Disorders
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 group | Role | What they receive |
|---|---|---|
| LP352 | Experimental | 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. Receives: Drug: LP352 |
| Placebo | Placebo comparator | Placebo for LP352 Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
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)
Safety and Tolerability of LP352
Safety and tolerability as measured by incidence and severity of 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), Columbia-Suicide Severity Rating Scale (C-SSRS) responses, and Patient Health Questionnaire-9 (PHQ-9) total score and Question 9 score.
Measured: Up to 21 Weeks
Percentage of participants with ≥ 50% Reduction in countable motor seizures during the Treatment compared to Baseline
Measured: Baseline and up to 15 Weeks
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.
- First posted5 Dec 2024
- Study start11 Nov 2024
- Primary completion31 Oct 2026 (estimated)
- Study completion30 Nov 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Developmental and Epileptic EncephalopathyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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
- 367 participants (actual)
Sponsor and investigators
- Lead sponsor
- Longboard Pharmaceuticals
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06719141
- Sponsor's protocol ID
- LP352-301
- Other IDs
- 2024-516412-17-00
- Status last verified
- Sep 2026
- First submitted
- 2 Dec 2024
- Last updated
- 15 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided