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Efficacy and Safety of GWP42003-P for Seizures Associated With Lennox-Gastaut Syndrome in Children and Adults

A Randomized, Double-blind, Placebo-controlled Study to Investigate the Efficacy and Safety of Cannabidiol (GWP42003-P; CBD) as Adjunctive Treatment for Seizures Associated With Lennox-Gastaut Syndrome in Children and Adults.

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02224560
Acronym
GWPCARE3
Enrollment
225
Registered
2014-08-25
Start date
2015-06-08
Completion date
2016-05-19
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, Lennox Gastaut Syndrome

Keywords

Cannabidiol, CBD, Epidiolex, GWP42003-P

Brief summary

The primary objective of this study was to evaluate the efficacy of GWP42003-P as adjunctive treatment in reducing the number of drop seizures when compared with placebo in participants with Lennox-Gastaut syndrome (LGS).

Detailed description

This study was a 1:1:1 randomized, double-blind, 14-week comparison of 2 dose levels (10 milligram \[mg\] per kilogram \[kg\] per day \[mg/kg/day\] and 20 mg/kg/day) of GWP42003-P versus placebo. Participants who satisfied all inclusion and none of the exclusion criteria began a 28-day baseline observation period. The treatment period consisted of a 2-week titration period followed by a 12-week maintenance period. The 20 mg/kg/day dose was recommended by the Data Safety Monitoring Committee (DSMC) after assessment of safety and pharmacokinetic data from Part A of study GWEP1332 (NCT02091206). The 10 mg/kg/day dose was defined as 50% of the 20 mg/kg/day dose. The first participant was not enrolled into this study until the DSMC had reviewed the safety data from Part A of study GWEP1332. Participants who satisfied all eligibility criteria were randomized at Day 1 to receive 10 mg/kg/day GWP42003-P, 20 mg/kg/day GWP42003-P, or placebo at a 1:1:1 ratio. Participants in the placebo group were split into 2 equivalent cohorts; one half received 10 mg/kg/day dosing volumes and one half received 20 mg/kg/day dosing volumes. The 2 placebo cohorts were pooled for the analyses of efficacy. Participants titrated GWP42003-P to the 10 mg/kg/day or 20 mg/kg/day (or equivalent volume of placebo) dose over 7 and 11 days, respectively, and remained at this dose for the 12-week maintenance period. Following the end of treatment (Day 99), participants were invited to continue to receive GWP42003-P in an open-label extension (OLE) study under a separate protocol (GWEP1415; NCT02224573). All participants who did not immediately enter the OLE study tapered investigational medicinal product (IMP) (10% per day over 10 days). However, the taper period could be interrupted if the participant wished to enter the OLE study within a 7-day timeframe. Participants who down-titrated IMP returned for an end of taper period visit (Day 109). Participants who did not enter the OLE study or who withdrew prematurely had a safety follow-up visit 28 days later (Day 137).

Interventions

GWP42003-P was presented as an oral solution containing 100 mg/milliliter (mL) cannabidiol (CBD) 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). Participants were randomly assigned to receive either 10 or 20 mg/kg/day.

DRUGPlacebo control

Placebo was presented as an oral solution containing 0 mg/mL CBD 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).

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 55 Years
Healthy volunteers
No

Inclusion criteria

Key Inclusion Criteria: * Participant and/or parent(s)/legal representatives were willing and able to give informed assent/consent for participation in the study. * Participant and his or her caregivers were willing and able (in the investigator's opinion) to comply with all study requirements. * Participant was male or female aged between 2 and 55 years (inclusive). * Participant had a documented history of LGS. This included written documentation of having met electroencephalogram (EEG) diagnostic criteria during the participant's history and evidence of at least 1 type of generalized seizure, including drop seizures (atonic, tonic, tonic-clonic or myoclonic) for at least 6 months. * Participant had a history of slow (\<3.0 hertz \[Hz\]) spike-and-wave pattern in an EEG prior to the enrollment into the baseline period. * Participant had at least 2 drop seizures each week during the first 28 days of the baseline period. * Participant was refractory; that is having documented failures on more than 1 antiepileptic drug (AED). * Participant was taking 1 or more AEDs at a dose which had been stable for at least 4 weeks prior to screening. * All medications or interventions for epilepsy (including ketogenic diet and vagus nerve stimulation \[VNS\]) were stable for 4 weeks prior to screening and the participant was willing to maintain a stable regimen throughout the study. The ketogenic diet and VNS treatments were not counted as an AED. * Participant and/or parent(s)/legal representatives were willing to allow his or her primary care practitioner and consultant to be notified of participation in the study. * Participant completed his or her interactive voice response (IVRS) telephone diary on at least 25 days of the baseline period. Key

Exclusion criteria

* Etiology of participant's seizures was a progressive neurologic disease. Participants with tuberous sclerosis were not excluded from study participation, unless there was a progressive tumor. * Participant had an anoxic episode requiring resuscitation within 6 months of screening. * Participant had clinically significant unstable medical conditions other than epilepsy. * Participant had clinically relevant symptoms or a clinically significant illness in the 4 weeks prior to screening or randomization, other than epilepsy. * Participant had a history or presence of alcohol or substance abuse within the last 2 years prior to the study or daily consumption of 5 or more alcohol-containing beverages. * Participant was currently using or had in the past used recreational or medicinal cannabis, or synthetic cannabinoid-based medications (including Sativex®) within the 3 months prior to study entry and was unwilling to abstain for the duration of the study. * Participant had a history of symptoms (for example, dizziness, light-headedness, blurred vision, palpitations, weakness, syncope) related to a drop in blood pressure due to postural changes. * Participant had any known or suspected hypersensitivity to cannabinoids or any of the excipients of the IMP, such as sesame oil. * Female participant was of child bearing potential or male participant's partner was of child bearing potential; unless willing to ensure that they or their partner used a highly effective method of contraception for the duration of the study and for 3 months thereafter. * Female participant was pregnant (positive pregnancy test), lactating or planning pregnancy during the course of the study and for 3 months thereafter. * Participant had been part of a clinical study involving another IMP in the previous 6 months. * Patient had significantly impaired hepatic function at screening (Day -28) or randomization (Day 1), defined as any of the following: alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \> 5 × upper limit of normal (ULN); ALT or AST \> 3 × ULN and total bilirubin \> 2 × ULN or international normalized ratio (INR) \> 1.5; ALT or AST \> 3 × ULN with the presence of fatigue, nausea, vomiting, right upper quadrant pain or tenderness, fever, rash, and/or eosinophilia (\>5%). This criterion could only be confirmed once the laboratory results were available; participants randomized into the study who were later found not to meet this criterion were withdrawn from the study. * Any history of suicidal behavior or any suicidal ideation of type 4 or 5 on the Columbia Suicide Severity Rating Scale in the last month or at screening. * Participant was unwilling to abstain from donation of blood during the study. * Participant planned to travel outside his or her country of residence during the study. * Participant had previously randomized into the study. * Participant was taking more than 4 concurrent AEDs. * Participant had taken corticotropins in the 6 months prior to screening. * Participant was currently taking long-term systemic steroids (excluding inhaled medication for asthma treatment) or any other daily medication known to exacerbate epilepsy. An exception was made of prophylactic medication, for example, idiopathic nephrotic syndrome or asthma. * Participant was taking felbamate, and he or she had been taking it for less than 1 year prior to screening.

Design outcomes

Primary

MeasureTime frameDescription
Percentage Change From Baseline In Drop Seizure Frequency During The Treatment PeriodBaseline to End of Treatment (EOT) (Day 99) or Early Termination (ET)Drop seizures were recorded by the participant or caregiver using an interactive voice response system (IVRS) diary. Drop seizures were defined as the subset of tonic-clonic, tonic or atonic seizures that were reported as drop seizures in the IVRS. Percentage change from baseline was calculated as: (\[frequency during the treatment period - frequency during baseline\]/frequency during baseline) x 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) x 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 ≥50% Reduction From Baseline In Drop Seizure Frequency During The Treatment PeriodBaseline to EOT (Day 99) or ETDrop seizures were recorded by the participant or caregiver using an IVRS diary. Drop seizures included the subset of tonic-clonic, tonic, or atonic seizures that were reported as drop seizures in IVRS. Percentage change from baseline was calculated as per the primary outcome measure.
Percentage Change From Baseline In Total Seizure Frequency During The Treatment PeriodBaseline to EOT (Day 99) or ETTotal seizures included the sum of all seizures (tonic-clonic, tonic, atonic, clonic, myoclonic, countable partial, other partial, and absence seizures) recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure. Negative percentages show an improvement from baseline.
Subject/Caregiver Global Impression Of Change (S/CGIC) AssessmentBaseline to Last Visit (Day 99) or ETThe S/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 S/CGIC questionnaire at subsequent visits. If both a CGIC and SGIC were completed then the CGIC was used; if only a CGIC was completed then the CGIC was used; if only a SGIC was completed then the SGIC was used. 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, Spain, United Kingdom, United States

Participant flow

Pre-assignment details

The dose levels of 10 and 20 milligram (mg) per kilogram (kg) per day (mg/kg/day) were recommended by the Data Safety Monitoring Committee (DSMC) of study GWEP1332 Part A (NCT02091206) after assessment of safety and pharmacokinetic data. Participants of GWEP1414 were not enrolled until the DSMC had reviewed the safety data of GWEP1332 Part A.

Participants by arm

ArmCount
GWP42003-P 20 mg/kg/Day Dose-ITT Analysis Set
Participants received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement; analyzed according to the treatment group to which they were randomized (GWP42003-P 20 mg/kg/day).
76
GWP42003-P 10 mg/kg/Day Dose-ITT Analysis Set
Participants received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement; analyzed according to the treatment group to which they were randomized (GWP42003-P 10 mg/kg/day).
73
Placebo-ITT Analysis Set
Participants received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement; analyzed according to the treatment group to which they were randomized (Placebo).
76
Total225

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
Overall StudyAdverse Event411
Overall StudyMet Withdrawal Criteria100
Overall StudyProtocol Deviation100
Overall StudyWithdrawal by Subject201
Overall StudyWithdrawn by Investigator110

Baseline characteristics

CharacteristicGWP42003-P 20 mg/kg/Day Dose-ITT Analysis SetGWP42003-P 10 mg/kg/Day Dose-ITT Analysis SetPlacebo-ITT Analysis SetTotal
Age, Continuous16.0 years
STANDARD_DEVIATION 10.8
15.4 years
STANDARD_DEVIATION 9.5
15.3 years
STANDARD_DEVIATION 9.3
15.6 years
STANDARD_DEVIATION 9.8
Sex: Female, Male
Female
31 Participants33 Participants32 Participants96 Participants
Sex: Female, Male
Male
45 Participants40 Participants44 Participants129 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
— / —— / —— / —
other
Total, other adverse events
63 / 8236 / 6740 / 76
serious
Total, serious adverse events
13 / 8213 / 678 / 76

Outcome results

Primary

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

Drop seizures were recorded by the participant or caregiver using an interactive voice response system (IVRS) diary. Drop seizures were defined as the subset of tonic-clonic, tonic or atonic seizures that were reported as drop seizures in the IVRS. Percentage change from baseline was calculated as: (\[frequency during the treatment period - frequency during baseline\]/frequency during baseline) x 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) x 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: Received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement. Participants were analyzed according to the treatment group to which they were randomized.

ArmMeasureValue (MEDIAN)
GWP42003-P 20 mg/kg/Day DosePercentage Change From Baseline In Drop Seizure Frequency During The Treatment Period-41.86 percentage change
GWP42003-P 10 mg/kg/Day DosePercentage Change From Baseline In Drop Seizure Frequency During The Treatment Period-37.16 percentage change
PlaceboPercentage Change From Baseline In Drop Seizure Frequency During The Treatment Period-17.17 percentage change
p-value: 0.004795% CI: [-34.79, -6.67]Wilcoxon rank-sum test
p-value: 0.001695% CI: [-31.24, -7.69]Wilcoxon rank-sum test
Secondary

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

Drop seizures were recorded by the participant or caregiver using an IVRS diary. Drop seizures included the subset of tonic-clonic, tonic, or atonic seizures that were reported as drop seizures in IVRS. 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: Received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement. Participants were analyzed according to the treatment group to which they were randomized.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseNumber Of Participants With A ≥50% Reduction From Baseline In Drop Seizure Frequency During The Treatment Period30 Participants
GWP42003-P 10 mg/kg/Day DoseNumber Of Participants With A ≥50% Reduction From Baseline In Drop Seizure Frequency During The Treatment Period26 Participants
PlaceboNumber Of Participants With A ≥50% Reduction From Baseline In Drop Seizure Frequency During The Treatment Period11 Participants
p-value: 0.000695% CI: [1.75, 8.47]Cochran-Mantel-Haenszel
p-value: 0.00395% CI: [1.47, 7.26]Cochran-Mantel-Haenszel
Secondary

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

Total seizures included the sum of all seizures (tonic-clonic, tonic, atonic, clonic, myoclonic, countable partial, other partial, and absence seizures) recorded by the participant or caregiver using an IVRS diary. Percentage change from baseline was calculated as per the primary outcome measure. Negative percentages show an improvement from baseline.

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

Population: ITT Analysis Set: Received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement. Participants were analyzed according to the treatment group to which they were randomized.

ArmMeasureValue (MEDIAN)
GWP42003-P 20 mg/kg/Day DosePercentage Change From Baseline In Total Seizure Frequency During The Treatment Period-38.40 percentage change
GWP42003-P 10 mg/kg/Day DosePercentage Change From Baseline In Total Seizure Frequency During The Treatment Period-36.44 percentage change
PlaceboPercentage Change From Baseline In Total Seizure Frequency During The Treatment Period-18.47 percentage change
p-value: 0.009195% CI: [-31.8, -4.43]Wilcoxon rank-sum test
p-value: 0.001595% CI: [-30.37, -7.47]Wilcoxon rank-sum test
Secondary

Subject/Caregiver Global Impression Of Change (S/CGIC) Assessment

The S/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 S/CGIC questionnaire at subsequent visits. If both a CGIC and SGIC were completed then the CGIC was used; if only a CGIC was completed then the CGIC was used; if only a SGIC was completed then the SGIC was used. 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: Received at least 1 dose of IMP with at least 1 post-baseline efficacy endpoint measurement. Participants were analyzed according to the treatment group to which they were randomized.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentMuch Improved15 Participants
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentSlightly Worse6 Participants
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentNo Change25 Participants
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentVery Much Improved6 Participants
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentVery Much Worse0 Participants
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentMuch Worse1 Participants
GWP42003-P 20 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentSlightly Improved22 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentNo Change21 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentVery Much Improved9 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentMuch Improved14 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentSlightly Improved25 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentSlightly Worse3 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentMuch Worse1 Participants
GWP42003-P 10 mg/kg/Day DoseSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentVery Much Worse0 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentSlightly Worse4 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentMuch Improved8 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentVery Much Worse0 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentMuch Worse3 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentNo Change35 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentSlightly Improved24 Participants
PlaceboSubject/Caregiver Global Impression Of Change (S/CGIC) AssessmentVery Much Improved1 Participants
p-value: 0.043995% CI: [1.02, 3.3]Regression, Logistic
p-value: 0.00295% CI: [1.41, 4.66]Regression, Logistic

Source: ClinicalTrials.gov · Data processed: Mar 4, 2026