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A Study of Soticlestat as an Add-on Therapy in Children, Teenagers, and Adults With Lennox-Gastaut Syndrome

A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel Group Study to Evaluate the Efficacy, Safety, and Tolerability of Soticlestat as Adjunctive Therapy in Pediatric and Adult Subjects With Lennox-Gastaut Syndrome (LGS)

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04938427
Enrollment
270
Registered
2021-06-24
Start date
2021-11-08
Completion date
2024-01-25
Last updated
2024-08-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Lennox Gastaut Syndrome (LGS)

Keywords

Drug therapy

Brief summary

The aims of the study are: * to learn if soticlestat, when given as add-on therapy, reduces the number of major motor drop seizures in children, teenagers, and adults with Lennox-Gastaut Syndrome. * to assess the safety profile of soticlestat when given in combination with other therapies. Participants will receive their standard antiseizure therapy, plus either tablets of soticlestat or placebo. A placebo looks just like soticlestat but will not have any medicine in it. Participants will take soticlestat or placebo for 16 weeks, followed by a gradual dose reduction for 1 week. Then, participants will be followed up for 2 weeks.

Detailed description

The drug being tested in this study is called soticlestat (TAK-935). Soticlestat will be assessed for efficacy, safety, and tolerability in pediatric and adult participants with LGS. The study will enroll approximately 234 patients. Participants will be randomly assigned (by chance, like flipping a coin) in a 1:1 ratio to receive standard of care (SOC) plus one of the following adjunctive therapies which will remain undisclosed to the participant and study doctor during the study (unless there is an urgent medical need): 1. Soticlestat 2. Placebo (dummy inactive pill - this is a tablet/mini-tablet that looks like the study drug but has no active ingredient) Participants will receive soticlestat or matching placebo based on their weight in the 4-week Titration Period. Following the Titration Period, participants will continue to receive the same dose in the 12-week Maintenance Period. The dose will then be down-tapered if participants decide to discontinue the treatment and/or are not deemed eligible to continue in Open-label extension (OLE). This multi-center trial will be conducted worldwide. The overall time to participate in the study will be from 22-25 weeks. At the end of the treatment period, participants have the option to either complete the study and taper off the investigational product or to enter the OLE if they meet eligibility requirements. If participants discontinue, they will be followed-up on phone call approximately 14 days after the last dose of study drug for safety.

Interventions

DRUGPlacebo

Soticlestat placebo-matching mini-tablets or tablets.

Soticlestat mini-tablets or tablets.

Sponsors

Takeda
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
2 Years to 55 Years
Healthy volunteers
No

Inclusion criteria

1. Has documented clinical diagnosis of LGS. 2. Has had ≥8 MMD seizures each month in the 3 months prior to Screening based on the historical information and has had ≥8 MMD seizures per 28 days during the 4 to 6 week prospective Baseline Period. 3. Weighs ≥10 kg at the Screening Visit (Visit 1). 4. Failure to control seizures despite appropriate trials of at least 1 ASM based on historical information, and is currently on an antiseizure therapy or other treatment options considered as standard of care (SOC). 5. Artisanal cannabidiols are allowed at a stable dose for at least 4 weeks before the screening visit (Visit 1); the dosing regimen and manufacturer should remain constant throughout the study. (Artisanal cannabidiols will not be counted as ASMs.) 6. Currently taking 0 to 3 ASMs at stable doses for at least 4 weeks before the Screening Visit (Visit 1); Fenfluramine and cannabidiol (Epidiolex) are allowed where available and counted as an ASM. ASM dosing regimen must remain constant throughout the study.

Exclusion criteria

1. Admitted to a medical facility and intubated for treatment of status epilepticus 2 or more times in the 3 months immediately before Screening (Visit 1). For the purpose of this exclusion criterion, status is defined as continuous seizure activity lasting longer than 5 minutes or repeated seizures without return to Baseline in between seizures. 2. Unstable, clinically significant neurologic (other than the disease being studied), psychiatric, cardiovascular, ophthalmologic, pulmonary, hepatic, renal, metabolic, gastrointestinal, urologic, immunologic, hematopoietic, endocrine disease, malignancy including progressive tumors, or other abnormality that may impact the ability to participate in the study or that may potentially confound the study results. It is the responsibility of the investigator to assess the clinical significance; however, consultation with the medical monitor may be warranted. 3. Considered by the investigator to be at imminent risk of suicide or injury to self, others, or property, or the participant has attempted suicide within 12 months before the Screening Visit (Visit 1). Participants who have positive answers on item numbers 4 or 5 on the Columbia suicide severity rating scale (C-SSRS) before dosing (Visit 2) are excluded. This scale will only be administered to participants aged ≥6 years.

Design outcomes

Primary

MeasureTime frameDescription
Percent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Full Treatment PeriodBaseline; Full Treatment Period: Weeks 1 to 16MMD seizure frequency per 28 days was defined as the total number of MMD seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the full Treatment Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.
Percent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Maintenance PeriodBaseline; Maintenance Period: Weeks 5 to 16MMD seizure frequency per 28 days was defined as the total number of MMD seizures reported during the period divided by number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the Maintenance Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Secondary

MeasureTime frameDescription
Percentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Percent reduction from Baseline (%) is defined as \[(Full Treatment Period MMD Seizure Frequency - Baseline MMD Seizure Frequency) divided by Baseline MMD Seizure Frequency\] multiplied by 100. Data is reported as reduction of ≤0%, \>0% to ≤25%, \>25% to ≤50%, \>50% to ≤75%, \>75% to ≤100% or more in seizures from Baseline. Percentages are rounded off to the nearest single decimal place.
Percentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Week 16The Care GI-I is a 7-point Likert scale that the caregiver used to rate improvement in overall seizure control, behavior, safety and tolerability after the initiation of study drug relative to Baseline (before treatment with the study drug). The participant was rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). The parent/caregiver completed the Care GI-I via interview. Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.
Percentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Week 16The CGI-I (Clinician) is a 7-point Likert scale that the investigator to rate a participant's change (improvement) in overall seizure control, behavior, safety and tolerability after the initiation of study drug relative to Baseline (before treatment with the study drug). The participant was rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). The investigator or designee will complete the CGI-I. Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.
Percentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Week 16The CGI-I nonseizure symptoms instrument is a series of single-item assessments that the investigator used to rate improvement in the symptoms and impacts in select nonseizure domains (alertness, communication, and disruptive behaviors) since initiating the study drug. The participant was rated by the investigator for each domain as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). Lower scores indicated improvement. Data for percentage of participants categorized based on the responses for each domain are presented. Percentages are rounded off to the nearest single decimal place.
Change From Baseline in Quality of Life Inventory-Disability (QI-Disability) Total Score at Week 16Baseline, Week 16The QI-Disability tool is a parent/caregiver-reported questionnaire evaluated the quality of life in children with intellectual disabilities. It contains 32 items covering 6 domains of quality of life: physical health, positive emotions, negative emotions, social interaction, leisure and the outdoors, and independence. Each QI-Disability item is rated on a Likert scale of: Never, Rarely, Sometimes, Often, and Very Often. Items were linearly transformed to a scale of 0 to 100, with higher scores representing better quality of life. Domain scores are calculated by averaging item scores. The domain scores are summed and divided by 6 to yield a total score. The total score ranges from 0 to 100, with higher scores indicating a better quality of life. A negative change from Baseline implies deteriorating quality of life. Mixed-effects model for repeated measures (MMRM) was used for analysis.
Percentage of Responders During the Maintenance PeriodMaintenance Period: Weeks 5 to 16Responders are defined as those with ≥50% reduction from Baseline in MMD seizures during the Maintenance Period. Percentages are rounded off to the nearest single decimal place.
Percent Change From Baseline in Frequency of All Seizures Per 28 Days During the Maintenance PeriodBaseline; Maintenance Period: Weeks 5 to 16Seizure frequency per 28 days was defined as the total number of seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the Maintenance Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.
Percent Change From Baseline in Frequency of All Seizures Per 28 Days During the Full Treatment PeriodBaseline; Full Treatment Period: Weeks 1 to 16Seizure frequency per 28 days was defined as the total number of seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the full Treatment Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.
Change From Baseline in Percentage of MMD Seizure-free Days During the Full Treatment PeriodBaseline up to Week 16MMD Seizure-free days was defined as the number of days the participant remained MMD seizure free after initiation of the treatment. The change from baseline in percentage of MMD seizure-free days, was defined as the percentage of seizure-free days during the Full Treatment Period minus the percentage of seizure-free days during the Baseline. A linear model with treatment group and age stratum as factors and baseline percentage as a covariate was used for analysis.
Longest MMD Seizure-free Interval During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Longest MMD Seizure-free Interval was defined as the longest time period that the participant remained MMD seizure-free after initiation of the treatment. A linear model with treatment group and age stratum as factors was used for analysis.
Number of Days When Rescue Antiseizure Medication (ASM) is Used During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Use of rescue ASM was recorded in the case report form (CRF) along with start and end date of medication. Based on the start and end dates for all rescue ASMs taken by a participant, the number of days during the Full Treatment Period when rescue ASM was used was derived.
Percentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Week 16The CGI-I seizure intensity and duration instrument was used by the parent/caregiver to rate changes in intensity and/or duration of the most impactful seizures from the first assessment. The participant's symptoms were rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.
Percentage of Responders During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Responders are defined as those with ≥50% reduction from Baseline in MMD seizures during the Full Treatment Period. Percentages are rounded off to the nearest single decimal place.

Countries

Australia, Belgium, Canada, China, France, Germany, Greece, Hungary, Italy, Japan, Latvia, Netherlands, Poland, Russia, Serbia, Spain, Ukraine, United States

Participant flow

Recruitment details

Participants took part in the study at 84 investigative sites in Australia, Belgium, Canada, China, France, Germany, Greece, Hungary, Italy, Japan, Latvia, Netherlands, Poland, Russian Federation, Serbia, Spain, Ukraine and the United States from 08 November 2021 to 25 January 2024.

Pre-assignment details

A total of 270 participants with a diagnosis of Lennox-Gastaut syndrome were randomized in a 1:1 ratio to receive either soticlestat or placebo.

Participants by arm

ArmCount
Placebo
Soticlestat placebo-matching mini-tablets or tablets, orally or via G-tube or MIC-KEY button or J-tube, BID, up to 4 weeks during titration. Participants continued to receive soticlestat placebo-matching mini-tablets or tablets for 12 weeks during maintenance. The total duration of the treatment was up to 16 weeks (Full Treatment Period). Soticlestat matching tapering was done to maintain the blind if participants decided to discontinue the treatment.
136
Soticlestat
Participants weighing \<45 kg: Soticlestat, mini-tablets, at the dose of 40 mg to 200 mg, orally or via G-tube or MIC-KEY button or J-tube, BID based on body weight up to 4 weeks during titration. Participants continued to receive the dose that they were on at the end of the titration, for 12 weeks during maintenance. The total duration of the treatment was up to 16 weeks (Full Treatment Period) with the dose tapered down if participants decided to discontinue the treatment. Participants weighing ≥45 kg: Soticlestat mini-tablets or tablets with a starting dose of 100 mg BID followed by 200 mg BID and, then 300 mg BID, up to 4 weeks during titration. Participants continued to receive 300 mg BID for 12 weeks during maintenance. The total duration of the treatment was up to 16 weeks (Full Treatment Period) with the dose tapered down if participants decided to discontinue the treatment.
134
Total270

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyAdverse Event519
Overall StudyReason Not Specified21
Overall StudyWithdrawal by Parent/Guardian20
Overall StudyWithdrawal by Subject10

Baseline characteristics

CharacteristicSoticlestatTotalPlacebo
Age, Continuous13.4 years
STANDARD_DEVIATION 9.35
12.9 years
STANDARD_DEVIATION 8.11
12.5 years
STANDARD_DEVIATION 6.68
Ethnicity (NIH/OMB)
Ethnicity
Hispanic or Latino
7 Participants11 Participants4 Participants
Ethnicity (NIH/OMB)
Ethnicity
Not Hispanic or Latino
124 Participants254 Participants130 Participants
Ethnicity (NIH/OMB)
Ethnicity
Unknown or Not Reported
3 Participants5 Participants2 Participants
Race (NIH/OMB)
Race
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Race
Asian
42 Participants86 Participants44 Participants
Race (NIH/OMB)
Race
Black or African American
1 Participants3 Participants2 Participants
Race (NIH/OMB)
Race
More than one race
0 Participants2 Participants2 Participants
Race (NIH/OMB)
Race
Native Hawaiian or Other Pacific Islander
0 Participants1 Participants1 Participants
Race (NIH/OMB)
Race
Unknown or Not Reported
5 Participants11 Participants6 Participants
Race (NIH/OMB)
Race
White
86 Participants167 Participants81 Participants
Sex: Female, Male
Gender
Female
55 Participants107 Participants52 Participants
Sex: Female, Male
Gender
Male
79 Participants163 Participants84 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 1360 / 134
other
Total, other adverse events
51 / 13669 / 134
serious
Total, serious adverse events
10 / 13611 / 134

Outcome results

Primary

Percent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Full Treatment Period

MMD seizure frequency per 28 days was defined as the total number of MMD seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the full Treatment Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Time frame: Baseline; Full Treatment Period: Weeks 1 to 16

Population: Modified Intent-to-treat (mITT) Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureValue (MEDIAN)
PlaceboPercent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Full Treatment Period-6.69 percent change
SoticlestatPercent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Full Treatment Period-6.11 percent change
p-value: =0.78595% CI: [-13.02, 9.99]ANCOVA
Primary

Percent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Maintenance Period

MMD seizure frequency per 28 days was defined as the total number of MMD seizures reported during the period divided by number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the Maintenance Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Time frame: Baseline; Maintenance Period: Weeks 5 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureValue (MEDIAN)
PlaceboPercent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Maintenance Period-9.63 percent change
SoticlestatPercent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Maintenance Period-5.24 percent change
p-value: =0.77895% CI: [-10.86, 15.14]ANCOVA
Secondary

Change From Baseline in Percentage of MMD Seizure-free Days During the Full Treatment Period

MMD Seizure-free days was defined as the number of days the participant remained MMD seizure free after initiation of the treatment. The change from baseline in percentage of MMD seizure-free days, was defined as the percentage of seizure-free days during the Full Treatment Period minus the percentage of seizure-free days during the Baseline. A linear model with treatment group and age stratum as factors and baseline percentage as a covariate was used for analysis.

Time frame: Baseline up to Week 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboChange From Baseline in Percentage of MMD Seizure-free Days During the Full Treatment Period5.37 percentage of daysStandard Error 1.661
SoticlestatChange From Baseline in Percentage of MMD Seizure-free Days During the Full Treatment Period7.84 percentage of daysStandard Error 1.676
95% CI: [-1.74, 6.67]
Secondary

Change From Baseline in Quality of Life Inventory-Disability (QI-Disability) Total Score at Week 16

The QI-Disability tool is a parent/caregiver-reported questionnaire evaluated the quality of life in children with intellectual disabilities. It contains 32 items covering 6 domains of quality of life: physical health, positive emotions, negative emotions, social interaction, leisure and the outdoors, and independence. Each QI-Disability item is rated on a Likert scale of: Never, Rarely, Sometimes, Often, and Very Often. Items were linearly transformed to a scale of 0 to 100, with higher scores representing better quality of life. Domain scores are calculated by averaging item scores. The domain scores are summed and divided by 6 to yield a total score. The total score ranges from 0 to 100, with higher scores indicating a better quality of life. A negative change from Baseline implies deteriorating quality of life. Mixed-effects model for repeated measures (MMRM) was used for analysis.

Time frame: Baseline, Week 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureValue (MEAN)Dispersion
PlaceboChange From Baseline in Quality of Life Inventory-Disability (QI-Disability) Total Score at Week 16-1.66 score on a scaleStandard Deviation 10.314
SoticlestatChange From Baseline in Quality of Life Inventory-Disability (QI-Disability) Total Score at Week 16-1.17 score on a scaleStandard Deviation 12.042
95% CI: [-2.2, 3.24]
Secondary

Longest MMD Seizure-free Interval During the Full Treatment Period

Longest MMD Seizure-free Interval was defined as the longest time period that the participant remained MMD seizure-free after initiation of the treatment. A linear model with treatment group and age stratum as factors was used for analysis.

Time frame: Full Treatment Period: Weeks 1 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboLongest MMD Seizure-free Interval During the Full Treatment Period5.5 daysStandard Error 1.39
SoticlestatLongest MMD Seizure-free Interval During the Full Treatment Period10.9 daysStandard Error 1.41
95% CI: [1.9, 8.9]
Secondary

Number of Days When Rescue Antiseizure Medication (ASM) is Used During the Full Treatment Period

Use of rescue ASM was recorded in the case report form (CRF) along with start and end date of medication. Based on the start and end dates for all rescue ASMs taken by a participant, the number of days during the Full Treatment Period when rescue ASM was used was derived.

Time frame: Full Treatment Period: Weeks 1 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboNumber of Days When Rescue Antiseizure Medication (ASM) is Used During the Full Treatment Period3.4 daysStandard Error 1.12
SoticlestatNumber of Days When Rescue Antiseizure Medication (ASM) is Used During the Full Treatment Period2.5 daysStandard Error 1.14
95% CI: [-3.7, 2]
Secondary

Percentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period

Percent reduction from Baseline (%) is defined as \[(Full Treatment Period MMD Seizure Frequency - Baseline MMD Seizure Frequency) divided by Baseline MMD Seizure Frequency\] multiplied by 100. Data is reported as reduction of ≤0%, \>0% to ≤25%, \>25% to ≤50%, \>50% to ≤75%, \>75% to ≤100% or more in seizures from Baseline. Percentages are rounded off to the nearest single decimal place.

Time frame: Full Treatment Period: Weeks 1 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>0% to ≤ 25% Reduction29.4 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>50% to ≤ 75% Reduction6.6 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>25% to ≤ 50% Reduction17.6 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>75% to ≤ 100% Reduction2.9 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period≤0% Reduction43.4 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>75% to ≤ 100% Reduction5.2 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period≤0% Reduction43.3 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>0% to ≤ 25% Reduction24.6 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>25% to ≤ 50% Reduction15.7 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment Period>50% to ≤ 75% Reduction11.2 percentage of participants
Secondary

Percentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16

The Care GI-I is a 7-point Likert scale that the caregiver used to rate improvement in overall seizure control, behavior, safety and tolerability after the initiation of study drug relative to Baseline (before treatment with the study drug). The participant was rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). The parent/caregiver completed the Care GI-I via interview. Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.

Time frame: Week 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 3: Minimally Improved25.4 percentage of participants
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 5: Minimally Worse11.5 percentage of participants
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 2: Much Improved13.1 percentage of participants
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 6: Much Worse3.1 percentage of participants
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 4: No Change46.2 percentage of participants
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 7: Very Much Worse0.0 percentage of participants
PlaceboPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 1: Very Much Improved0.8 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 7: Very Much Worse2.5 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 1: Very Much Improved1.6 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 2: Much Improved20.5 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 3: Minimally Improved26.2 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 4: No Change36.9 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 5: Minimally Worse6.6 percentage of participants
SoticlestatPercentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 6: Much Worse5.7 percentage of participants
95% CI: [0.86, 2.13]
Secondary

Percentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16

The CGI-I nonseizure symptoms instrument is a series of single-item assessments that the investigator used to rate improvement in the symptoms and impacts in select nonseizure domains (alertness, communication, and disruptive behaviors) since initiating the study drug. The participant was rated by the investigator for each domain as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). Lower scores indicated improvement. Data for percentage of participants categorized based on the responses for each domain are presented. Percentages are rounded off to the nearest single decimal place.

Time frame: Week 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 1: Very Much Improved1.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 2: Much Improved7.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 3: Minimally Improved12.8 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 4: No Change71.4 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 5: Minimally Worse4.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 6: Much Worse2.3 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 7: Very Much Worse0.0 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 1: Very Much Improved1.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 2: Much Improved7.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 3: Minimally improved12.8 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 4: No Change71.4 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 5: Minimally Worse4.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 6: Much Worse2.3 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 7: Very Much Worse0.0 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 1: Very Much Improved0.0 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 2: Much Improved1.5 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 3: Minimally improved8.3 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 4: No Change79.7 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 5: Minimally Worse6.8 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 6: Much Worse3.8 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 7: Very Much Worse0.0 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 4: No Change61.4 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 1: Very Much Improved1.5 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 5: Minimally Worse3.8 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 2: Much Improved13.6 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 5: Minimally Worse6.1 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 3: Minimally Improved16.7 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 3: Minimally improved10.6 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 4: No Change59.1 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 6: Much Worse0.8 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 5: Minimally Worse8.3 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 7: Very Much Worse0.8 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 6: Much Worse0.8 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 7: Very Much Worse0.0 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Alertness: Score 7: Very Much Worse0.0 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 4: No Change75.0 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 1: Very Much Improved2.3 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 1: Very Much Improved1.5 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 2: Much Improved10.6 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 6: Much Worse2.3 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 3: Minimally improved18.9 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 2: Much Improved6.1 percentage of participants
Comparison: Alertness Domain95% CI: [0.85, 2.3]
Comparison: Communication Domain95% CI: [0.91, 2.48]
Comparison: Disruptive Behaviors Domain95% CI: [1.06, 3.43]
Secondary

Percentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16

The CGI-I seizure intensity and duration instrument was used by the parent/caregiver to rate changes in intensity and/or duration of the most impactful seizures from the first assessment. The participant's symptoms were rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.

Time frame: Week 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 3: Minimally Improved24.4 percentage of participants
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 5: Minimally Worse9.9 percentage of participants
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 2: Much Improved9.9 percentage of participants
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 6: Much Worse3.8 percentage of participants
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 4: No Change51.1 percentage of participants
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 7: Very Much Worse0.0 percentage of participants
PlaceboPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 1: Very Much Improved0.8 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 7: Very Much Worse1.6 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 1: Very Much Improved1.6 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 2: Much Improved18.9 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 3: Minimally Improved28.7 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 4: No Change39.3 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 5: Minimally Worse4.1 percentage of participants
SoticlestatPercentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Score 6: Much Worse5.7 percentage of participants
95% CI: [1.06, 2.65]
Secondary

Percentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16

The CGI-I (Clinician) is a 7-point Likert scale that the investigator to rate a participant's change (improvement) in overall seizure control, behavior, safety and tolerability after the initiation of study drug relative to Baseline (before treatment with the study drug). The participant was rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). The investigator or designee will complete the CGI-I. Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.

Time frame: Week 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 3: Minimally Improved17.3 percentage of participants
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 5: Minimally Worse5.3 percentage of participants
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 2: Much Improved11.3 percentage of participants
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 6: Much Worse4.5 percentage of participants
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 4: No Change60.2 percentage of participants
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 7: Very Much Worse0.0 percentage of participants
PlaceboPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 1: Very Much Improved1.5 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 7: Very Much Worse1.5 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 1: Very Much Improved3.0 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 2: Much Improved15.9 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 3: Minimally Improved24.2 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 4: No Change43.2 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 5: Minimally Worse7.6 percentage of participants
SoticlestatPercentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Score 6: Much Worse4.5 percentage of participants
95% CI: [0.89, 2.21]
Secondary

Percentage of Responders During the Full Treatment Period

Responders are defined as those with ≥50% reduction from Baseline in MMD seizures during the Full Treatment Period. Percentages are rounded off to the nearest single decimal place.

Time frame: Full Treatment Period: Weeks 1 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureValue (NUMBER)
PlaceboPercentage of Responders During the Full Treatment Period9.6 percentage of participants
SoticlestatPercentage of Responders During the Full Treatment Period16.4 percentage of participants
95% CI: [0.92, 4.05]
Secondary

Percentage of Responders During the Maintenance Period

Responders are defined as those with ≥50% reduction from Baseline in MMD seizures during the Maintenance Period. Percentages are rounded off to the nearest single decimal place.

Time frame: Maintenance Period: Weeks 5 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureValue (NUMBER)
PlaceboPercentage of Responders During the Maintenance Period11.4 percentage of participants
SoticlestatPercentage of Responders During the Maintenance Period19.4 percentage of participants
95% CI: [0.94, 3.87]
Secondary

Percent Change From Baseline in Frequency of All Seizures Per 28 Days During the Full Treatment Period

Seizure frequency per 28 days was defined as the total number of seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the full Treatment Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Time frame: Baseline; Full Treatment Period: Weeks 1 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period.

ArmMeasureValue (MEDIAN)
PlaceboPercent Change From Baseline in Frequency of All Seizures Per 28 Days During the Full Treatment Period-6.45 percent change
SoticlestatPercent Change From Baseline in Frequency of All Seizures Per 28 Days During the Full Treatment Period-16.71 percent change
95% CI: [-16.67, 3.12]
Secondary

Percent Change From Baseline in Frequency of All Seizures Per 28 Days During the Maintenance Period

Seizure frequency per 28 days was defined as the total number of seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the Maintenance Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Time frame: Baseline; Maintenance Period: Weeks 5 to 16

Population: mITT Analysis Set included all randomized participants who had received at least 1 dose of study drug and had been assessed for seizures for at least 1 day in the Full Treatment Period. Overall number of participants analyzed indicates the number of participants with data available for analyses.

ArmMeasureValue (MEDIAN)
PlaceboPercent Change From Baseline in Frequency of All Seizures Per 28 Days During the Maintenance Period-9.92 percent change
SoticlestatPercent Change From Baseline in Frequency of All Seizures Per 28 Days During the Maintenance Period-16.82 percent change
95% CI: [-16.83, 4.16]

Source: ClinicalTrials.gov · Data processed: Mar 29, 2026