LP352 for Dravet Syndrome

Recruiting at 160 trial locations

Overseen By Longboard Study Contact

Age: Any Age

Sex: Any

Trial Phase: Phase 3

Sponsor: Longboard Pharmaceuticals

Must be taking: Antiseizure medications

Must not be taking: Cannabis products

Disqualifiers: Infantile spasms, Neurodegenerative disorders, others

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 7

160 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new treatment, LP352, for Dravet Syndrome, a severe form of epilepsy that causes frequent and intense seizures. The researchers aim to determine how well LP352 reduces seizures and assess its safety and tolerability compared to a placebo (a non-active treatment). Participants will receive either LP352 or a placebo during the study. Individuals who have experienced seizures like tonic-clonic or myoclonic and have had at least four seizures per month, despite using one to four anti-seizure medications, might be suitable for this trial. As a Phase 3 trial, this study represents the final step before FDA approval, offering participants a chance to contribute to a potentially groundbreaking treatment.

Will I have to stop taking my current medications?

The trial requires participants to have been taking 1 to 4 antiseizure medications at a stable dose for at least 4 weeks before the study, so you may need to continue your current antiseizure medications. However, if you are taking any exclusionary medications, you may need to stop those.

Is there any evidence suggesting that LP352 is likely to be safe for humans?

Research has shown that LP352 was safe in earlier studies. Most participants tolerated the treatment well, with sleepiness as the most common side effect. While the treatment might cause drowsiness, most patients have found it manageable.

The current trial is a Phase 3 study, indicating that LP352 has already undergone safety testing in earlier stages. This phase focuses on confirming its effectiveness and identifying any new side effects in a larger group. So far, earlier data indicate positive safety results. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising for Dravet Syndrome?

Most treatments for Dravet Syndrome, like valproate or clobazam, aim to control seizures by modulating neurotransmitter activity. But LP352 works differently, targeting specific serotonin receptors to potentially reduce seizure frequency and severity. This unique mechanism of action may provide an alternative for patients who do not respond well to existing medications. Researchers are excited about LP352 because it could offer a new avenue for managing Dravet Syndrome with possibly fewer side effects.

What evidence suggests that LP352 might be an effective treatment for Dravet Syndrome?

Research has shown that LP352, which participants in this trial may receive, might help reduce seizures in people with Dravet Syndrome. In earlier studies, some patients experienced more than a 50% reduction in seizure frequency. This is significant because Dravet Syndrome is typically difficult to treat. LP352 works by targeting specific areas of the brain to help control seizures. Although more information is needed, these early results are promising and suggest that LP352 could be a useful option for managing seizures in Dravet Syndrome. ^{2 4 6 7 8}

Are You a Good Fit for This Trial?

This trial is for children and adults with Dravet Syndrome, a severe form of epilepsy. Participants must be experiencing seizures despite current treatments. Specific details on who can or cannot participate are not provided here.

Inclusion Criteria

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 specific seizure types, The participant has a current occurrence of specific motor seizure types, 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 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, psychiatric, cardiovascular, 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

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Titration

Participants are titrated up to the highest tolerated dose of LP352

4 weeks

Visit 2 - Visit 5

Maintenance

Participants maintain the highest tolerated dose of LP352

6 weeks

Visit 5 - Visit 8

Taper

Participants taper off the study medication

2 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• LP352

Trial Overview The study tests LP352 against a placebo to see if it's better at treating seizures in Dravet Syndrome patients. It's double-blind, meaning neither the researchers nor participants know who gets the real drug or placebo during the trial.

How Is the Trial Designed?

Group I: LP352 Experimental Treatment 1 Intervention

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.

Group II: Placebo Placebo Group 1 Intervention

Placebo for LP352

Who Is Running the Clinical Trial?

Longboard Pharmaceuticals

Lead Sponsor

Trials

5

Recruited

570+

Citations

1. clinicaltrials.gov clinicaltrials.gov/study/NCT06660394

A Phase 3, Placebo-Controlled Study to Investigate LP352 ... This (DEEp SEA Study) is a double-blind, randomized, placebo-controlled, multicenter study to investigate the efficacy, safety, and tolerability of LP352 in ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10582139/

Pharmacotherapy for Dravet Syndrome: A Systematic Review ... The efficacy outcomes were the proportions of participants with ≥ 50% (seizure response) and 100% reduction (seizure freedom) in baseline ...

3. lundbeck.com lundbeck.com/us/newsroom/2025/lundbeck-announces-positive-results-from-12-month-open-label-ext

Lundbeck announces positive results from 12-month Open ... Bexicaserin achieved an overall median seizure reduction of 59.3 percent in countable motor seizures over a 12-month open-label extension (OLE) treatment ...

4. dravetfoundation.org dravetfoundation.org/dsf-funded-research/treatment-pipeline/

Current Clinical Trials & Treatment Pipeline The Dravet Genome Study, funded by DSF, will explore the diverse spectrum of outcomes that occur within Dravet syndrome and other SCN1A-related epilepsies ...

5. clinicaltrialsarena.com clinicaltrialsarena.com/news/longboard-dravet-syndrome-trial/

Longboard begins Phase III Dravet syndrome treatment trial The placebo-controlled, double-blind trial will enrol approximately 160 subjects between the ages of two and 65 years.

6. clinicaltrials.gov clinicaltrials.gov/study/NCT05626634

Open-label, Long-term Safety Study of LP352 in Subjects ... The objective of this study is to assess the long-term safety, tolerability, and efficacy of adjunctive therapy of LP352 in subjects with developmental and ...

7. dravetsyndromenews.com dravetsyndromenews.com/news/dravet-syndrome-treatment-bexicaserin-shows-promise-trial/

Dravet syndrome treatment bexicaserin shows promise in ... Safety data from PACIFIC showed bexicaserin was generally tolerated well by most patients. The most common side effects were sleepiness or ...

8. firstwordpharma.com firstwordpharma.com/story/5814289

Longboard Pharmaceuticals Announces Positive Topline ... Summary of Safety Data: Bexicaserin exhibited favorable safety and ... syndrome, Dravet syndrome and other DEEs. Longboard is also ...