A Phase 2 interventional study of LP352, bexicaserin in Developmental and Epileptic Encephalopathy, Dravet Syndrome and Lennox-Gastaut Syndrome, sponsored by Longboard Pharmaceuticals. Completed at 28 sites in 2 countries. Open to participants aged 12 Years to 65 Years. Per ClinicalTrials.gov, last updated 2025-12-03.
Sponsored by Longboard Pharmaceuticals (part of H. Lundbeck A/S) · Phase 2, Interventional, and Treatment
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 epileptic encephalopathies who completed participation in Study LP352-201.
This Phase 2, multicenter, open-label, multiple-dose extension clinical study is designed to evaluate long-term safety of LP352 in subjects with developmental and epileptic encephalopathy who completed Study LP352-201.
The study consists of a Screening Period (Day -1) and a 50-week open-label Treatment Period that includes a 15-day Up-titration Period (during which time subjects will titrate up to their highest tolerated doses) and an open-label Maintenance Period (48 weeks). The Treatment Period will be followed by a Down-titration/Taper Period (up to 15 days) and Follow-up Period (14 days after completion of down-titration). The starting dose of up-titration will be 6 mg TID. The target final maintenance doses are 6 mg TID, 9 mg TID, and 12 mg TID after a 15-day up-titration period, if tolerated.
92 studies on the registry are indexed under Epilepsies, Myoclonic; 21 are open to participants now.
This study's enrollment of 41 is above the median of 31 across 56 interventional studies indexed under Epilepsies, Myoclonic.
Browse Epilepsies, Myoclonic studies →Longboard Pharmaceuticals is the lead sponsor of 6 studies on the registry; 2 are open to participants now.
First submitted before Longboard Pharmaceuticals became part of H. Lundbeck A/S.
Counted across the registry records on this site, refreshed daily.
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Exclusion Criteria:
Subjects will be titrated up to highest tolerated dose of LP352 during a 15-day period, followed by a 48-week maintenance period and a 15-day taper/down titration period.
Drug: LP352, bexicaserin
LP352 6 mg, 9 mg or 12 mg administered three times daily, orally or through G-tube
Treatment-emergent Adverse Events
Incidence and severity of treatment-emergent adverse events, including serious adverse events and adverse events leading to study discontinuation and clinically significant changes in vital signs, physical examination endpoints, clinical safety laboratory values and ECGs
Time frame: Baseline up to Week 52
Columbia-Suicide Severity Rating Scale (C-SSRS) Response
Type of Suicidal Ideation, Intensity (1 - 5, with 5 being most severe), Suicidal Behavior
Time frame: Baseline up to Week 52
Patient Health Questionnaire-9 Total Score and Question 9 Score
Severity Rating Scale: 0 - 27; higher scores indicate greater severity of depressive disorder
Time frame: Baseline up to Week 52
Percent Change from Baseline in Observed Countable Motor Seizure Frequency During the Treatment Period
Baseline Used for Seizure Frequency = Baseline from Study LP352-201 and Baseline from Study LP352-202
Time frame: Baseline to Week 50
Proportion of Subjects with > 50% Reduction in Total Seizures During the Treatment Period
Time frame: Baseline to Week 50
Percent Reduction in Individual Seizure Type During the Treatment Period
Time frame: Baseline to Week 50
Proportion of Subjects Requiring Rescue Medication During the Treatment Period
Time frame: Baseline to Week 50
Percent Change from Baseline in the Number of Episodes of Status Epilepticus During the Treatment Period
Time frame: Baseline to Week 50
Percent of Subjects with Countable Motor Seizure-free Days During the Treatment Period
Time frame: Baseline to Week 50
Percentage Change from Baseline in Non-motor and Difficult to Count Seizures
Time frame: Baseline to Week 50
LGS: Percentage Change from Baseline in the Frequency of Observed Drop Seizures Over the Treatment Period
Time frame: Baseline to Week 50
Ran from Nov 2022 to primary completion in Dec 2024, 25 months.
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This study is completed, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Bexicaserin