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Antiepileptic Efficacy Study of GWP42003-P in Children and Young Adults With Dravet Syndrome (GWPCARE1)

A Double Blind, Placebo Controlled Two-part Study to Investigate the Dose-ranging Safety and Pharmacokinetics, Followed by the Efficacy and Safety of Cannabidiol (GWP42003-P) in Children and Young Adults With Dravet Syndrome

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02091375
Enrollment
120
Registered
2014-03-19
Start date
2015-03-30
Completion date
2015-11-26
Last updated
2022-09-28

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

Conditions

Epilepsy, Dravet Syndrome

Keywords

Cannabidiol, CBD, Epidiolex, GWP42003-P

Brief summary

To investigate the potential antiepileptic effects of cannabidiol (GWP42003-P) in children and young adults with Dravet syndrome.

Detailed description

GWEP1332 Part B recruited an entirely new group of participants than GWEP1332 Part A. Participants who failed the entry criteria for Part A were eligible to take part in Part B. Part B was a 1:1 randomized, double-blind, placebo-controlled, 14-week comparison of GWP42003-P versus placebo. The aim of Part B was to assess the antiepileptic efficacy of GWP42003-P as an adjunctive antiepileptic treatment compared with placebo, with respect to the percentage change from baseline during the treatment period of the study in convulsive seizure frequency in children and young adults. Following the establishment of initial eligibility and baseline measurements, participants entered Part B and began a 28-day baseline observation period. Eligible participants were then randomized to receive either GWP42003-P or placebo on a 1:1 basis and titrated up to the target dose that was identified in Part A (up to 20 milligrams \[mg\] per kilogram \[kg\] per day), which was confirmed following completion of Part A by an independent Data Safety Monitoring Committee who reviewed unblinded safety and pharmacokinetic data from Part A. Participants received investigational medicinal product for 14 weeks, consisting of a titration period followed by a 12-week maintenance period. Efficacy and safety were monitored at various clinic visits and via telephone. After 14 weeks of treatment, all participants were offered the option of entering an open label extension (OLE) study. Entry was within seven days of the final treatment visit. Participants who did not immediately enter the OLE study commenced a down-titration taper period lasting up to 10 days. The taper period was interrupted if the participant wished to enter the open label extension study within the seven-day timeframe. For participants who opted not to enter the OLE study, a follow-up telephone call was made 28 days after the end of dosing and weekly safety telephone calls were made during the 28-day follow-up period.

Interventions

GWP42003-P was an oral solution containing 100 mg/milliliter (mL) cannabidiol (CBD) dissolved in the excipients, sesame oil and anhydrous ethanol (79 mg/mL), with added sweetener (0.5 mg/mL sucralose) and strawberry flavoring (0.2 mg/mL).

DRUGPlacebo control

Placebo oral solution contained the excipients, sesame oil and anhydrous ethanol (79 mg/mL), with added sweetener (0.5 mg/mL sucralose) and strawberry flavoring (0.2 mg/mL).

Sponsors

Jazz Pharmaceuticals
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 18 Years
Healthy volunteers
No

Inclusion criteria

Key Inclusion Criteria: * Participants were male or female aged between 2 and 18 years (inclusive). * Participants had a documented history of Dravet Syndrome that was not completely controlled by current antiepileptic drugs. * Participants took one or more antiepileptic drugs at a dose that had been stable for at least four weeks. * All medications or interventions for epilepsy (including ketogenic diet and vagus nerve stimulation) were stable for four weeks prior to screening and participants were willing to maintain a stable regimen throughout the study. Key

Exclusion criteria

* Participants had clinically significant unstable medical conditions other than epilepsy. * Participants had clinically relevant symptoms or a clinically significant illness in the four weeks prior to screening or randomization, other than epilepsy. * Participants were currently using or had in the past used recreational or medicinal cannabis or synthetic cannabinoid based medications (including Sativex®) within the three months prior to study entry and were unwilling to abstain for the duration for the study. * Participants had any known or suspected hypersensitivity to cannabinoids or any of the excipients of the investigational medicinal products. * Participants had been part of a previous clinical trial involving another investigational product in the previous six months. * There were plans for the participants to travel outside their country of residence during the study. * Participants previously randomized into this study. In particular, participants who participated in Part A of the study could not enter Part B.

Design outcomes

Primary

MeasureTime frameDescription
Percentage Change From Baseline In Convulsive Seizure Frequency During The Treatment PeriodBaseline to End of Treatment (EOT) (Day 99) or Early Termination (ET)Convulsive seizures (atonic, clonic, tonic, or tonic-clonic) were recorded by the participant or caregiver using an interactive voice response system (IVRS) diary. Percentage change from baseline was calculated as: (\[frequency during the treatment period - frequency during baseline\]/frequency during baseline) \* 100. The frequency during each period was based on 28-day averages and calculated as: (number of seizures in the period/number of reported days in the IVRS period) \* 28. Baseline included all available data prior to Day 1 (28-day average). Negative percentages show an improvement from baseline.

Secondary

MeasureTime frameDescription
Number of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment PeriodBaseline to EOT (Day 99) or ETConvulsive seizures (atonic, clonic, tonic, or tonic-clonic) were recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure.
Percentage Change From Baseline In Non-Convulsive Seizure Frequency During The Treatment PeriodBaseline to EOT (Day 99) or ETNon-convulsive seizures (myoclonic, partial, or absence) were recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure. Only participants with non-convulsive seizures during the baseline period were included. Negative percentages show an improvement from baseline.
Caregiver Global Impression Of Change In Seizure Duration (CGICSD)Baseline to EOT (Day 99) or ETSeizure duration was assessed qualitatively using the CGICSD. Caregivers were asked Since the patient started treatment, please assess the average duration of the patient's seizures (comparing their condition now to their condition before treatment); responses included decrease, no change, or increase in average duration. For each seizure type, only participants with at least 1 seizure for the corresponding seizure type, reported at any time during the study, were included.
Number Of Participants Using Rescue MedicationBaseline to EOT (Day 99) or ETThe use of rescue medication was recorded by the participant or caregiver using a paper diary.
Number Of Participants With Inpatient Hospitalizations Due To EpilepsyBaseline to Safety Follow-up (Day 137)Inpatient hospitalizations due to epilepsy were recorded by the participant or caregiver and through the serious adverse events (SAE) reporting process.
Number Of Participants With A ≥50% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment PeriodBaseline to EOT (Day 99) or ETConvulsive seizures (atonic, clonic, tonic, or tonic-clonic) were recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure.
Change From Baseline In Epworth Sleepiness Scale (ESS) ScoreBaseline to Last Visit (Day 99) or ETThe ESS questionnaire was completed by the participant's caregiver. The change from baseline in the ESS score was analyzed using an ANCOVA model with baseline and age group (2 to 5 years, 6- to 2 years and 13 to 18 years) as covariates and treatment group as a fixed factor. The total score was the sum of the 8 item-scores and ranged from 0 to 24. A higher total score represents greater levels of daytime sleepiness.
Change From Baseline In Quality Of Life In Childhood Epilepsy (QOLCE) ScoreBaseline to EOT (Day 99) or ETThe QOLCE questionnaire was completed by the parent or caregiver of participants aged 4 years and above. The change from baseline in the overall quality of life score was analyzed using an ANCOVA model with baseline and age group (2 to 5 years, 6 to 12 years and 13 to 18 years) as covariates and treatment group as a fixed factor. Zero represents the lowest or poorest category and 100 represents the highest level of functioning. The overall quality of life score was calculated by taking the mean of the subscale scores.
Change From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreBaseline to Last Visit (Day 99) or ETThe Vineland-II scores (standard scores and adaptive levels for each adaptive behavior domain, the adaptive behavior composite, and the maladaptive behavior index score and level) were assessed by the participant's caregiver. Scores were analyzed using an ANCOVA model with baseline and age group (2 to 5 years, 6 to 12 years, and 13 to 18 years) as covariates and treatment group as a fixed factor. Higher scores represent greater levels of functioning except for the maladaptive behavior index, for which a negative change from baseline represents an improvement in condition.
Caregiver Global Impression Of Change (CGIC)Baseline to Last Visit (Day 99) or ETThe CGIC was used to assess the participant's overall condition on a 7-point scale using the markers very much improved, much improved, slightly improved, no change, slightly worse, much worse, or very much worse (1 = very much improved; 7 = very much worse). On Day 1 (prior to starting IMP), the caregiver was asked to write a brief description of the participant's overall condition as a memory aid for the CGIC questionnaire at subsequent visits.
Change From Baseline In Sleep Disruption 0 To 10 Numerical Rating Scale (0 to 10 NRS) ScoreBaseline to Last Visit (Day 99) or ETThe sleep disruption 0 to 10 NRS questionnaire was completed by the participant's caregiver. The caregiver was asked 'On a scale of '0 to 10', please indicate the number that best describes your child's sleep disruption in the last week.' The markers ranged from 0 = 'slept extremely well' to 10 = 'unable to sleep at all'. The change from baseline in the sleep disruption 0 to 10 numerical rating scale score was analyzed using an analysis of covariance (ANCOVA) model with baseline and age group (2 to 5 years, 6 to 12 years and 13 to 18 years) as covariates and treatment group as a fixed factor. A negative change from baseline represents an improvement in sleep. Last visit for endpoints assessed at clinic visits was defined as the last scheduled visit (not including the end of taper or safety follow-up visits) at which participant's last evaluation was performed.

Countries

France, Poland, United Kingdom, United States

Participant flow

Participants by arm

ArmCount
GWP42003-P 20 mg/kg/Day Dose
Participants received 20 mg/kg/day of GWP42003-P administered orally, half in the morning and half in the evening. Participants titrated GWP42003-P to 20 mg/kg/day over 11 days and remained at this dose for the 12-week maintenance period. If the participant did not immediately enter the OLE study, the maintenance period was followed by a 10-day taper (10% per day) period. Participants received at least 1 dose of IMP; analyzed according to the actual treatment received (GWP42003-P).
61
Placebo
Participants received placebo (0 mg/mL CBD), volume-matched to the 20 mg/kg/day dose level, administered orally, half in the morning and half in the evening. To maintain the blinded aspect of the study, participants titrated the placebo dose over 11 days and remained at this dose for the 12-week maintenance period. If the participant did not immediately enter the OLE study, the maintenance period was followed by a 10-day taper (10% per day of the matched dose) period. Participants received at least 1 dose of IMP; analyzed according to the actual treatment received (placebo).
59
Total120

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyAdverse Event81
Overall StudyLost to Follow-up01
Overall StudyWithdrawal by Subject01
Overall StudyWithdrawn by the investigator10

Baseline characteristics

CharacteristicGWP42003-P 20 mg/kg/Day DosePlaceboTotal
Age, Continuous9.736 Years
STANDARD_DEVIATION 4.7309
9.779 Years
STANDARD_DEVIATION 4.8505
9.757 Years
STANDARD_DEVIATION 4.7699
Sex: Female, Male
Female
26 Participants32 Participants58 Participants
Sex: Female, Male
Male
35 Participants27 Participants62 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
46 / 6128 / 59
serious
Total, serious adverse events
10 / 613 / 59

Outcome results

Primary

Percentage Change From Baseline In Convulsive Seizure Frequency During The Treatment Period

Convulsive seizures (atonic, clonic, tonic, or tonic-clonic) were recorded by the participant or caregiver using an interactive voice response system (IVRS) diary. Percentage change from baseline was calculated as: (\[frequency during the treatment period - frequency during baseline\]/frequency during baseline) \* 100. The frequency during each period was based on 28-day averages and calculated as: (number of seizures in the period/number of reported days in the IVRS period) \* 28. Baseline included all available data prior to Day 1 (28-day average). Negative percentages show an improvement from baseline.

Time frame: Baseline to End of Treatment (EOT) (Day 99) or Early Termination (ET)

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureValue (MEDIAN)
GWP42003-P 20 mg/kg/Day DosePercentage Change From Baseline In Convulsive Seizure Frequency During The Treatment Period-38.94 percent change
PlaceboPercentage Change From Baseline In Convulsive Seizure Frequency During The Treatment Period-13.29 percent change
p-value: 0.012395% CI: [-41.06, -5.43]Wilcoxon rank-sum test
Secondary

Caregiver Global Impression Of Change (CGIC)

The CGIC was used to assess the participant's overall condition on a 7-point scale using the markers very much improved, much improved, slightly improved, no change, slightly worse, much worse, or very much worse (1 = very much improved; 7 = very much worse). On Day 1 (prior to starting IMP), the caregiver was asked to write a brief description of the participant's overall condition as a memory aid for the CGIC questionnaire at subsequent visits.

Time frame: Baseline to Last Visit (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)Slightly Improved18 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)Slightly Worse3 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)Much Improved10 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)Much Worse4 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)No Change15 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)Very Much Worse1 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change (CGIC)Very Much Improved9 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)Very Much Worse0 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)Very Much Improved4 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)Much Improved4 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)Slightly Improved12 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)No Change31 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)Slightly Worse6 Participants
PlaceboCaregiver Global Impression Of Change (CGIC)Much Worse1 Participants
Secondary

Caregiver Global Impression Of Change In Seizure Duration (CGICSD)

Seizure duration was assessed qualitatively using the CGICSD. Caregivers were asked Since the patient started treatment, please assess the average duration of the patient's seizures (comparing their condition now to their condition before treatment); responses included decrease, no change, or increase in average duration. For each seizure type, only participants with at least 1 seizure for the corresponding seizure type, reported at any time during the study, were included.

Time frame: Baseline to EOT (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureGroupCategoryValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic SeizuresNo change in average duration8 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic-Clonic SeizuresDecrease in average duration17 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic-Clonic SeizuresNo change in average duration32 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic-Clonic SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic SeizuresDecrease in average duration4 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Clonic SeizuresDecrease in average duration5 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Clonic SeizuresNo change in average duration6 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Clonic SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Atonic SeizuresDecrease in average duration2 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Atonic SeizuresNo change in average duration1 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Atonic SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Myoclonic SeizuresDecrease in average duration4 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Myoclonic SeizuresNo change in average duration10 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Myoclonic SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Countable Partial SeizuresDecrease in average duration5 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Countable Partial SeizuresNo change in average duration7 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Countable Partial SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Other Partial SeizuresDecrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Other Partial SeizuresNo change in average duration3 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Other Partial SeizuresIncrease in average duration0 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Absence SeizuresDecrease in average duration4 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Absence SeizuresNo change in average duration11 Participants
GWP42003-P 20 mg/kg/Day DoseCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Absence SeizuresIncrease in average duration1 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Absence SeizuresNo change in average duration12 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic SeizuresNo change in average duration12 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Myoclonic SeizuresDecrease in average duration3 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Other Partial SeizuresDecrease in average duration3 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic-Clonic SeizuresDecrease in average duration8 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Myoclonic SeizuresNo change in average duration12 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic-Clonic SeizuresNo change in average duration31 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Absence SeizuresDecrease in average duration6 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic-Clonic SeizuresIncrease in average duration2 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Myoclonic SeizuresIncrease in average duration3 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic SeizuresDecrease in average duration2 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Tonic SeizuresIncrease in average duration1 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Other Partial SeizuresNo change in average duration2 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Clonic SeizuresDecrease in average duration3 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Countable Partial SeizuresDecrease in average duration2 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Clonic SeizuresNo change in average duration3 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Absence SeizuresIncrease in average duration1 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Clonic SeizuresIncrease in average duration1 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Countable Partial SeizuresNo change in average duration9 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Atonic SeizuresDecrease in average duration2 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Other Partial SeizuresIncrease in average duration0 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Atonic SeizuresNo change in average duration3 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Countable Partial SeizuresIncrease in average duration2 Participants
PlaceboCaregiver Global Impression Of Change In Seizure Duration (CGICSD)Atonic SeizuresIncrease in average duration2 Participants
Secondary

Change From Baseline In Epworth Sleepiness Scale (ESS) Score

The ESS questionnaire was completed by the participant's caregiver. The change from baseline in the ESS score was analyzed using an ANCOVA model with baseline and age group (2 to 5 years, 6- to 2 years and 13 to 18 years) as covariates and treatment group as a fixed factor. The total score was the sum of the 8 item-scores and ranged from 0 to 24. A higher total score represents greater levels of daytime sleepiness.

Time frame: Baseline to Last Visit (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureValue (LEAST_SQUARES_MEAN)
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Epworth Sleepiness Scale (ESS) Score0.82 units on a scale
PlaceboChange From Baseline In Epworth Sleepiness Scale (ESS) Score-0.69 units on a scale
Secondary

Change From Baseline In Quality Of Life In Childhood Epilepsy (QOLCE) Score

The QOLCE questionnaire was completed by the parent or caregiver of participants aged 4 years and above. The change from baseline in the overall quality of life score was analyzed using an ANCOVA model with baseline and age group (2 to 5 years, 6 to 12 years and 13 to 18 years) as covariates and treatment group as a fixed factor. Zero represents the lowest or poorest category and 100 represents the highest level of functioning. The overall quality of life score was calculated by taking the mean of the subscale scores.

Time frame: Baseline to EOT (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureValue (LEAST_SQUARES_MEAN)
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Quality Of Life In Childhood Epilepsy (QOLCE) Score5.6 units on a scale
PlaceboChange From Baseline In Quality Of Life In Childhood Epilepsy (QOLCE) Score4.1 units on a scale
Secondary

Change From Baseline In Sleep Disruption 0 To 10 Numerical Rating Scale (0 to 10 NRS) Score

The sleep disruption 0 to 10 NRS questionnaire was completed by the participant's caregiver. The caregiver was asked 'On a scale of '0 to 10', please indicate the number that best describes your child's sleep disruption in the last week.' The markers ranged from 0 = 'slept extremely well' to 10 = 'unable to sleep at all'. The change from baseline in the sleep disruption 0 to 10 numerical rating scale score was analyzed using an analysis of covariance (ANCOVA) model with baseline and age group (2 to 5 years, 6 to 12 years and 13 to 18 years) as covariates and treatment group as a fixed factor. A negative change from baseline represents an improvement in sleep. Last visit for endpoints assessed at clinic visits was defined as the last scheduled visit (not including the end of taper or safety follow-up visits) at which participant's last evaluation was performed.

Time frame: Baseline to Last Visit (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureValue (LEAST_SQUARES_MEAN)
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Sleep Disruption 0 To 10 Numerical Rating Scale (0 to 10 NRS) Score-0.7 units on a scale
PlaceboChange From Baseline In Sleep Disruption 0 To 10 Numerical Rating Scale (0 to 10 NRS) Score-0.3 units on a scale
Secondary

Change From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) Score

The Vineland-II scores (standard scores and adaptive levels for each adaptive behavior domain, the adaptive behavior composite, and the maladaptive behavior index score and level) were assessed by the participant's caregiver. Scores were analyzed using an ANCOVA model with baseline and age group (2 to 5 years, 6 to 12 years, and 13 to 18 years) as covariates and treatment group as a fixed factor. Higher scores represent greater levels of functioning except for the maladaptive behavior index, for which a negative change from baseline represents an improvement in condition.

Time frame: Baseline to Last Visit (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreCommunication Domain Standard Score-0.8 units on a scale
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreDaily Living Skills Domain Standard Score-0.8 units on a scale
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreSocialization Domain Standard Score-0.6 units on a scale
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreMotor Skills Domain Standard Score-2.5 units on a scale
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreAdaptive Behavior Composite Standard Score-2.0 units on a scale
GWP42003-P 20 mg/kg/Day DoseChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreMaladaptive Behavior Index v-Scale Score-0.3 units on a scale
PlaceboChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreAdaptive Behavior Composite Standard Score0.6 units on a scale
PlaceboChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreCommunication Domain Standard Score3.0 units on a scale
PlaceboChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreMotor Skills Domain Standard Score1.7 units on a scale
PlaceboChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreDaily Living Skills Domain Standard Score-0.8 units on a scale
PlaceboChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreMaladaptive Behavior Index v-Scale Score-0.4 units on a scale
PlaceboChange From Baseline In Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) ScoreSocialization Domain Standard Score-0.6 units on a scale
Secondary

Number Of Participants Using Rescue Medication

The use of rescue medication was recorded by the participant or caregiver using a paper diary.

Time frame: Baseline to EOT (Day 99) or ET

Population: Safety Analysis Set: included all participants randomized to treatment who received at least 1 dose of IMP. Participants were analyzed according to the actual treatment they received.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseNumber Of Participants Using Rescue Medication36 Participants
PlaceboNumber Of Participants Using Rescue Medication41 Participants
Secondary

Number of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period

Convulsive seizures (atonic, clonic, tonic, or tonic-clonic) were recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure.

Time frame: Baseline to EOT (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseNumber of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period≥25% Reduction38 Participants
GWP42003-P 20 mg/kg/Day DoseNumber of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period≥75% Reduction14 Participants
GWP42003-P 20 mg/kg/Day DoseNumber of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period100% Reduction3 Participants
PlaceboNumber of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period≥25% Reduction26 Participants
PlaceboNumber of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period≥75% Reduction7 Participants
PlaceboNumber of Participants With A ≥25%, ≥75% Or 100% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period100% Reduction0 Participants
Secondary

Number Of Participants With A ≥50% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period

Convulsive seizures (atonic, clonic, tonic, or tonic-clonic) were recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure.

Time frame: Baseline to EOT (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseNumber Of Participants With A ≥50% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period26 Participants
PlaceboNumber Of Participants With A ≥50% Reduction From Baseline In Convulsive Seizure Frequency During The Treatment Period16 Participants
p-value: 0.078495% CI: [0.93, 4.3]Cochran-Mantel-Haenszel
Secondary

Number Of Participants With Inpatient Hospitalizations Due To Epilepsy

Inpatient hospitalizations due to epilepsy were recorded by the participant or caregiver and through the serious adverse events (SAE) reporting process.

Time frame: Baseline to Safety Follow-up (Day 137)

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureGroupValue (NUMBER)
GWP42003-P 20 mg/kg/Day DoseNumber Of Participants With Inpatient Hospitalizations Due To EpilepsyCaregiver/participant-reported5 participants
GWP42003-P 20 mg/kg/Day DoseNumber Of Participants With Inpatient Hospitalizations Due To EpilepsyInvestigator-reported (serious TEAE)2 participants
PlaceboNumber Of Participants With Inpatient Hospitalizations Due To EpilepsyCaregiver/participant-reported1 participants
PlaceboNumber Of Participants With Inpatient Hospitalizations Due To EpilepsyInvestigator-reported (serious TEAE)1 participants
Secondary

Percentage Change From Baseline In Non-Convulsive Seizure Frequency During The Treatment Period

Non-convulsive seizures (myoclonic, partial, or absence) were recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure. Only participants with non-convulsive seizures during the baseline period were included. Negative percentages show an improvement from baseline.

Time frame: Baseline to EOT (Day 99) or ET

Population: ITT analysis set: included all participants in the Part B safety analysis set who had post-baseline efficacy data. Participants were analyzed according to the treatment group to which they were randomized. The ITT analysis set was the primary analysis set for all efficacy outcome measures.

ArmMeasureValue (MEDIAN)
GWP42003-P 20 mg/kg/Day DosePercentage Change From Baseline In Non-Convulsive Seizure Frequency During The Treatment Period-40.16 percent change
PlaceboPercentage Change From Baseline In Non-Convulsive Seizure Frequency During The Treatment Period-34.69 percent change

Source: ClinicalTrials.gov · Data processed: Feb 26, 2026