A Phase 3, placebo-controlled study to investigate LP352 in children and adults with Developmental and Epileptic Encephalopathies

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Longboard Pharmaceuticals Inc.

Participant type

Pediatric, Patients

Age range

0-17 years, 18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Nervous System Diseases [C10]

Trial duration

26 Aug 2025 → ongoing

Decision date (initial)

2025-06-13

Transition trial

No

Low-intervention

No

Rare-disease indication

Yes

Vulnerable population

Yes

Funding sources

Longboard Pharmaceuticals, Inc

External identifiers

EU CT number

2024-516412-17-00

ClinicalTrials.gov

NCT06719141

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Efficacy, Safety

To evaluate the efficacy of LP352 in Developmental and Epileptic Encephalopathy as assessed by countable motor seizures

Secondary objectives 1

1. To evaluate the efficacy of LP352 in Developmental and Epileptic Encephalopathy

Conditions and MedDRA coding

Developmental and Epileptic Encephalopathies (DEE)

Regulatory references

Scientific advice from competent authorities

European Medicines Agency, Food And Drug Administration

EMA paediatric investigation plan (PIP)

EMEA-003288-PIP01-22

Plan to share IPD

No

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 3

1. • Participants who are characterized as having Lennox-Gastaut Syndrome (LGS) must fulfill all of the following criteria: o Onset of seizures at ≤8 years old o 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 o Presence of developmental plateauing or regression
2. • Participants who are characterized as having DEE (Other) must fulfill all of the following criteria: o Does not meet criteria for LGS o Onset of seizures at ≤5 years old o Presence of developmental plateauing or regression o History of multiple seizure types
3. • Additional specific main inclusion criteria include the following: o 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. o The participant has demonstrated an average of at least 4 countable motor seizures per month for each of the 3 months prior to Screening. o The participant has been taking 1 to 4 antiseizure medications (ASMs) at a stable dose for at least 4 weeks prior to Screening. o 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. o 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 must provide informed consent and the participant will need to assent (as per local regulations) before participation in the study.

Exclusion criteria 8

1. • The participant has a diagnosis of Dravet Syndrome (DS)
2. • The participant has been admitted to a medical facility for treatment of status epilepticus requiring mechanical ventilation within 3 months prior to Screening.
3. • The participant has a neurodegenerative disorder as indicated by magnetic resonance imaging or genetic testing.
4. • The participant has an acquired lesion/injury unrelated to the primary etiology that could contribute as a secondary cause of seizures.
5. • The participant is receiving exclusionary medications.
6. • The participant has used of 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).
7. • 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.
8. • The participant is unable or unwilling to comply with any of the study requirements or timelines.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Frequency percent change in countable motor seizures during Maintenance compared to Baseline

Secondary endpoints 1

1. 1.• 50% responder rate (the percentage of participants with a ≥50% reduction in countable motor seizures) during Maintenance compared to Baseline• Frequency percent change in countable motor seizures during Treatment compared to Baseline

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Longboard Pharmaceuticals Inc.

Sponsor organisation

Longboard Pharmaceuticals Inc.

Address

4275 Executive Square Suite 950

City

La Jolla

Postcode

92037-9208

Country

United States

Scientific contact point

Organisation

Longboard Pharmaceuticals Inc.

Contact name

Global Regulatory Lead

Public contact point

Organisation

Longboard Pharmaceuticals Inc.

Contact name

Global Regulatory Lead

Third parties 11

Locations

11 EU/EEA countries · 47 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 296 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

8 submissions — initial application plus substantial / non-substantial modifications