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A Study of Soticlestat as an Add-on Therapy in Children and Young Adults With Dravet 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 Young Adult Subjects With Dravet Syndrome (DS)

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04940624
Enrollment
144
Registered
2021-06-25
Start date
2021-10-28
Completion date
2024-04-11
Last updated
2025-01-01

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

Conditions

Dravet Syndrome (DS)

Keywords

Drug Therapy

Brief summary

The main aim of the study is to learn if soticlestat, when given as an add-on therapy, reduces the number of convulsive seizures in children and young adults with DS. Participants will receive their standard antiseizure therapy, plus either a tablet of soticlestat or placebo for 16 weeks. A placebo looks just like soticlestat but will not have any medicine in it. Participants may continue treatment in an extension study, based on the extension study's entry criteria. Those that want to stop treatment will have a gradual dose reduction during 1 week and then be followed up for 2 weeks.

Detailed description

The drug being tested in this study is called soticlestat (TAK-935). Soticlestat as an adjunctive therapy will be assessed for efficacy, safety, and tolerability in pediatric and adult participants with DS. The study will enroll approximately 142 pediatric and young adult patients. Participants will be randomized at a 1:1 ratio to receive standard of care (SOC) plus one of the following adjunctive therapies: * Soticlestat or * Placebo The total daily dose of study drug will be calculated based on body weight in the 4 weeks Titration Period. Following the Titration Period, participants will continue to receive the same dose in the 12-weeks Maintenance Period. 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 Full 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

Soticlestat mini-tablets or tablets.

DRUGPlacebo

Soticlestat placebo-matching 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 21 Years
Healthy volunteers
No

Inclusion criteria

1. Has documented clinical diagnosis of DS. 2. Had ≥12 convulsive seizures over 12 weeks before screening based on the historical information and has had ≥4 convulsive 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 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 4 ASMs at stable doses for at least 4 weeks before the screening visit (Visit 1); benzodiazepines used chronically (daily) to treat seizures are considered ASMs. Fenfluramine and cannabidiol (Epidiolex) are allowed where available and should be counted as an ASM. ASM dosing regimen must remain constant throughout the study.

Exclusion criteria

1\. 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.

Design outcomes

Primary

MeasureTime frameDescription
Percent Change From Baseline in Convulsive Seizure Frequency Per 28 Days During the Full Treatment PeriodBaseline; Full Treatment Period: Weeks 1 to 16Convulsive seizure frequency per 28 days was defined as the total number of convulsive 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 Convulsive Seizure Frequency Per 28 Days During the Maintenance PeriodBaseline; Maintenance Period: Weeks 5 to 16Convulsive seizure frequency per 28 days was defined as the total number of convulsive 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 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%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Percent reduction from Baseline (%) was defined as \[(Full Treatment Period Convulsive Seizure Frequency - Baseline Convulsive Seizure Frequency) divided by Baseline Convulsive Seizure Frequency\] multiplied by 100. Data was reported as reduction of ≤0%, \>0% to ≤25%, \>25% to ≤50%, \>50% to ≤75%, \>75% to ≤100% or more in seizures from Baseline. Percentages were 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 were 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 used 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 completed the CGI-I. Lower scores indicate improvement. Percentages were 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 non-seizure symptoms instrument is a series of single-item assessments that the investigator used to rate improvement in the symptoms and impacts in select non-seizure 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 were 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 that 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 Maintenance PeriodMaintenance Period: Weeks 5 to 16Responders were defined as those with ≥50% reduction from Baseline in convulsive seizures during the Maintenance Period. Percentages were 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 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 Convulsive Seizure-free Days During the Full Treatment PeriodBaseline up to Week 16Convulsive seizure-free days was defined as number of days a participant remained convulsive seizure-free after initiation of the treatment. The change from baseline in percentage of convulsive 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 Convulsive Seizure-free Interval During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Longest convulsive seizure-free interval was defined as the longest time period that the participant remained convulsive 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 on 7-point scale 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 were rounded off to the nearest single decimal place.
Percentage of Responders During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16Responders were defined as those with ≥50% reduction from Baseline in convulsive seizures during the Full Treatment Period. Percentages were rounded off to the nearest single decimal place.

Countries

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

Participant flow

Recruitment details

A total of 144 participants participated in the study at multiple investigative sites globally from 28 October 2021 to 11 April 2024.

Pre-assignment details

A total of 144 participants with a diagnosis of Dravet Syndrome (DS) 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 the 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.
71
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 the 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 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 dose tapered down if participants decided to discontinue the treatment.
73
Total144

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyAdverse Event411
Overall StudyLost to Follow-up10
Overall StudyPhysician Decision10
Overall StudyReason Not Specified10
Overall StudyWithdrawal by Parent/Guardian12

Baseline characteristics

CharacteristicSoticlestatTotalPlacebo
Age, Continuous10.1 years
STANDARD_DEVIATION 5.04
10.3 years
STANDARD_DEVIATION 5.04
10.5 years
STANDARD_DEVIATION 5.06
Ethnicity (NIH/OMB)
Hispanic or Latino
5 Participants11 Participants6 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
68 Participants130 Participants62 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants3 Participants3 Participants
Race (NIH/OMB)
American Indian or Alaska Native
1 Participants1 Participants0 Participants
Race (NIH/OMB)
Asian
27 Participants51 Participants24 Participants
Race (NIH/OMB)
Black or African American
3 Participants3 Participants0 Participants
Race (NIH/OMB)
More than one race
1 Participants1 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants6 Participants4 Participants
Race (NIH/OMB)
White
39 Participants82 Participants43 Participants
Sex: Female, Male
Female
37 Participants72 Participants35 Participants
Sex: Female, Male
Male
36 Participants72 Participants36 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 711 / 73
other
Total, other adverse events
37 / 7140 / 73
serious
Total, serious adverse events
10 / 717 / 73

Outcome results

Primary

Percent Change From Baseline in Convulsive Seizure Frequency Per 28 Days During the Full Treatment Period

Convulsive seizure frequency per 28 days was defined as the total number of convulsive 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 one dose of study drug and had been assessed for seizures for at least one day in the Full Treatment Period.

ArmMeasureValue (MEDIAN)
PlaceboPercent Change From Baseline in Convulsive Seizure Frequency Per 28 Days During the Full Treatment Period-8.64 percent change
SoticlestatPercent Change From Baseline in Convulsive Seizure Frequency Per 28 Days During the Full Treatment Period-22.16 percent change
p-value: =0.06195% CI: [-31.3, 0.24]ANCOVA
Primary

Percent Change From Baseline in Convulsive Seizure Frequency Per 28 Days During the Maintenance Period

Convulsive seizure frequency per 28 days was defined as the total number of convulsive 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 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 one dose of study drug and had been assessed for seizures for at least one 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 Convulsive Seizure Frequency Per 28 Days During the Maintenance Period-11.99 percent change
SoticlestatPercent Change From Baseline in Convulsive Seizure Frequency Per 28 Days During the Maintenance Period-23.29 percent change
p-value: =0.08995% CI: [-30.51, 1.53]ANCOVA
Secondary

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

Convulsive seizure-free days was defined as number of days a participant remained convulsive seizure-free after initiation of the treatment. The change from baseline in percentage of convulsive 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 one dose of study drug and had been assessed for seizures for at least one day in the Full Treatment Period.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboChange From Baseline in Percentage of Convulsive Seizure-free Days During the Full Treatment Period2.74 percentage of daysStandard Error 1.784
SoticlestatChange From Baseline in Percentage of Convulsive Seizure-free Days During the Full Treatment Period3.54 percentage of daysStandard Error 1.719
95% CI: [-3.81, 5.4]
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 that 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 one dose of study drug and had been assessed for seizures for at least one 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 162.81 score on a scaleStandard Deviation 10.119
SoticlestatChange From Baseline in Quality of Life Inventory-Disability (QI-Disability) Total Score at Week 16-1.23 score on a scaleStandard Deviation 15.438
p-value: =0.18995% CI: [-7.59, 1.52]MMRM
Secondary

Longest Convulsive Seizure-free Interval During the Full Treatment Period

Longest convulsive seizure-free interval was defined as the longest time period that the participant remained convulsive 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 one dose of study drug and had been assessed for seizures for at least one day in the Full Treatment Period.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboLongest Convulsive Seizure-free Interval During the Full Treatment Period16.7 daysStandard Error 2.15
SoticlestatLongest Convulsive Seizure-free Interval During the Full Treatment Period22.3 daysStandard Error 2.08
95% CI: [0.1, 11.2]
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 one dose of study drug and had been assessed for seizures for at least one 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 Period4.0 daysStandard Error 0.81
SoticlestatNumber of Days When Rescue Antiseizure Medication (ASM) is Used During the Full Treatment Period2.9 daysStandard Error 0.78
95% CI: [-3.1, 1]
Secondary

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

Percent reduction from Baseline (%) was defined as \[(Full Treatment Period Convulsive Seizure Frequency - Baseline Convulsive Seizure Frequency) divided by Baseline Convulsive Seizure Frequency\] multiplied by 100. Data was reported as reduction of ≤0%, \>0% to ≤25%, \>25% to ≤50%, \>50% to ≤75%, \>75% to ≤100% or more in seizures from Baseline. Percentages were 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 one dose of study drug and had been assessed for seizures for at least one day in the Full Treatment Period.

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>0% to ≤25% Reduction32.4 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>50% to ≤75% Reduction8.5 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>25% to ≤50% Reduction18.3 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>75% to ≤100% Reduction1.4 percentage of participants
PlaceboPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period≤0% Reduction39.4 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>75% to ≤100% Reduction13.7 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period≤0% Reduction31.5 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>0% to ≤25% Reduction20.5 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>25% to ≤50% Reduction20.5 percentage of participants
SoticlestatPercentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, and >75% to ≤100% Reduction in Convulsive Seizures During the Full Treatment Period>50% to ≤75% Reduction13.7 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 were 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 one dose of study drug and had been assessed for seizures for at least one 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 Improved22.1 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 7: Very Much Worse1.5 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 1: Very Much Improved1.5 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 Improved11.8 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 Change47.1 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 5: Minimally Worse10.3 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 Worse5.9 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 7: Very Much Worse1.5 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 4: No Change27.3 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 Worse3.0 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 Improved4.5 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 5: Minimally Worse7.6 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 Improved27.3 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 Improved28.8 percentage of participants
p-value: =0.00495% CI: [1.33, 4.72]Cumulative Logit Model
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 non-seizure symptoms instrument is a series of single-item assessments that the investigator used to rate improvement in the symptoms and impacts in select non-seizure 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 were 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 one dose of study drug and had been assessed for seizures for at least one 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 6: Much Worse1.4 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 Worse5.6 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 1: Very Much Improved2.8 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 2: Much Improved8.5 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 Improved14.1 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 Change67.6 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 Improved1.4 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 2: Much Improved11.3 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 3: Minimally Improved18.3 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 4: No Change62.0 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 5: Minimally Worse4.2 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 Worse2.8 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 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 Improved1.4 percentage of participants
PlaceboPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 2: Much Improved4.2 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 Improved14.1 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 Change69.0 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 5: Minimally Worse11.3 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 6: 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 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 Change62.0 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 5: Minimally Worse8.5 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 5: Minimally Worse4.2 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 Improved7.0 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 3: Minimally Improved16.9 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 6: Much Worse1.4 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 3: Minimally Improved14.1 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Disruptive Behaviors: Score 7: Very Much Worse1.4 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 4: No Change70.4 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 5: Minimally Worse4.2 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 Improved4.2 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 Worse0.0 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 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 Change64.8 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 1: Very much Improved4.2 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 Improved1.4 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 2: Much Improved5.6 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 Worse1.4 percentage of participants
SoticlestatPercentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Communication: Score 3: Minimally Improved22.5 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 2: Much Improved5.6 percentage of participants
Comparison: Alertnessp-value: =0.74195% CI: [0.56, 2.26]Cumulative Logit Model
Comparison: Communicationp-value: =0.90195% CI: [0.54, 2.02]Cumulative Logit Model
Comparison: Disruptive Behaviorsp-value: =0.69395% CI: [0.58, 2.28]Cumulative Logit Model
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 on 7-point scale 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 were 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 one dose of study drug and had been assessed for seizures for at least one 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 7: Very Much Worse1.4 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 6: Much Worse8.7 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 3: Minimally Improved15.9 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 Improved4.3 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 Change59.4 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 1: Very Much Improved4.3 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 Worse5.8 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 1: Very Much Improved10.8 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 6: Much Worse6.2 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 Worse0.0 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 Worse1.5 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 Improved24.6 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 3: Minimally Improved23.1 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 4: No Change33.8 percentage of participants
p-value: <0.00195% CI: [1.87, 7.13]Cumulative Logit Model
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 used 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 completed the CGI-I. Lower scores indicate improvement. Percentages were 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 one dose of study drug and had been assessed for seizures for at least one 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 2: Much Improved8.5 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 Change59.2 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 1: Very Much Improved2.8 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 3: Minimally Improved15.5 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 6: Much Worse8.5 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 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 5: Minimally Worse5.6 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 7: Very Much Worse0.0 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 6: Much Worse1.4 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 Improved7.0 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 Improved25.4 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 Improved19.7 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 Change38.0 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 5: Minimally Worse8.5 percentage of participants
p-value: =0.00395% CI: [1.37, 4.87]Cumulative Logit Model
Secondary

Percentage of Responders During Maintenance Period

Responders were defined as those with ≥50% reduction from Baseline in convulsive seizures during the Maintenance Period. Percentages were 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 one dose of study drug and had been assessed for seizures for at least one 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 Maintenance Period11.8 percentage of participants
SoticlestatPercentage of Responders During Maintenance Period30.4 percentage of participants
p-value: =0.0195% CI: [1.3, 7.96]Cochran-Mantel-Haenszel
Secondary

Percentage of Responders During the Full Treatment Period

Responders were defined as those with ≥50% reduction from Baseline in convulsive seizures during the Full Treatment Period. Percentages were 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 one dose of study drug and had been assessed for seizures for at least one day in the Full Treatment Period.

ArmMeasureValue (NUMBER)
PlaceboPercentage of Responders During the Full Treatment Period9.9 percentage of participants
SoticlestatPercentage of Responders During the Full Treatment Period27.4 percentage of participants
p-value: =0.00895% CI: [1.36, 9.49]Cochran-Mantel-Haenszel
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 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 one dose of study drug and had been assessed for seizures for at least one 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-7.46 percent change
SoticlestatPercent Change From Baseline in Frequency of All Seizures Per 28 Days During the Full Treatment Period-9.27 percent change
p-value: =0.63794% CI: [-26.31, 10.13]ANCOVA
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 one dose of study drug and had been assessed for seizures for at least one 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-11.89 percent change
SoticlestatPercent Change From Baseline in Frequency of All Seizures Per 28 Days During the Maintenance Period-17.24 percent change
p-value: =0.56595% CI: [-29.01, 7.87]ANCOVA

Source: ClinicalTrials.gov · Data processed: Mar 6, 2026