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Note: This record shows only 22 elements of the WHO Trial Registration Data Set. To view changes that have been made to the source record, or for additional information about this trial, click on the URL below to go to the source record in the primary register.
Last refreshed on: 22 February 2021
Main ID:  NCT03848832
Date of registration: 19/02/2019
Prospective Registration: Yes
Primary sponsor: GW Research Ltd
Public title: Efficacy and Safety of Cannabidiol Oral Solution (GWP42003-P, CBD-OS) in Patients With Rett Syndrome ARCH
Scientific title: A Randomized, Double-blind, Placebo-controlled Trial to Investigate the Efficacy and Safety of Cannabidiol Oral Solution (GWP42003-P, CBD-OS) in Patients With Rett Syndrome
Date of first enrolment: July 29, 2019
Target sample size: 252
Recruitment status: Terminated
Study type:  Interventional
Study design:  Allocation: Randomized. Intervention model: Parallel Assignment. Primary purpose: Treatment. Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor).  
Phase:  Phase 3
Countries of recruitment
Italy Spain United Kingdom United States
Key inclusion & exclusion criteria

Key Inclusion Criteria:

- Participant (if possessing adequate understanding, in the investigator's opinion)
and/or her parent(s)/legal representative is willing and able to give informed
consent/assent for participation in the trial.

- Participant and her caregiver are willing and able (in the investigator's opinion) to
comply with all trial requirements (including the completion of all caregiver
assessments by the same caregiver throughout the trial).

- Participant must weigh at least 10 kilograms.

- Clinical diagnosis of Rett syndrome (typical or atypical), defined according to
RettSearch Consortium criteria

- Confirmed pathogenic genetic mutation of the MECP2 gene

- Participant must be post-regression (= 6 months since last loss of hand use or verbal
language or gross motor regression).

- Participant must have a disease severity of between 10 and 36, defined according to
the Clinical Severity Scale (CSS).

- All medications or interventions (including antiepileptic drugs [AEDs] and
non-pharmacological interventions - dietary supplements, probiotics, physical therapy,
speech therapy, etc.) for Rett syndrome-related symptoms must have been stable for 4
weeks prior to screening and the participant/caregiver must be willing to maintain a
stable regimen throughout the trial.

- Ability to swallow the investigational medicinal product (IMP) provided as a liquid
solution, or the ability for IMP to be delivered via gastrostomy (G) or nasogastric
(NG) feeding tube (only G-or NG-tubes made from polyurethane or silicon are allowed)

- Participant and/or parent(s)/legal representative is willing to allow the responsible
authorities to be notified of participation in the trial, if mandated by local law.

- Participant and/or parent(s)/legal representative is willing to allow the
participant's primary care practitioner (if she has one) and consultant (if she has
one) to be notified of participation in the trial, if the primary care
practitioner/consultant is different to the investigator.

Key Exclusion Criteria:

- Participant meets exclusion criteria for Rett syndrome diagnosis (traumatic brain
injury, neurometabolic disease, or severe infection that causes neurological problems;
grossly abnormal psychomotor development in the first 6 months of life).

- Participant has clinically significant abnormal laboratory values, in the
investigator's opinion.

- Participant is taking more than 2 concurrent AEDs.

- Any history of suicidal behavior or any suicidal ideation in the last month or at

- Clinically relevant abnormalities in the electrocardiogram (ECG) measured at screening
or randomization

- Concurrent cardiovascular conditions which will, in the investigator's opinion,
interfere with the ability to assess her ECGs or put the participant at risk because
of participation in the trial

- First or second degree relative with a history of significant ECG abnormalities, in
the opinion of the investigator (e.g. premature cardiac arrest, sudden death)

- Any known or suspected hypersensitivity to cannabinoids or any of the excipients of
the IMP (active or placebo), such as sesame oil

- Participant has moderately impaired hepatic function at screening, defined as alanine
aminotransferase (ALT) or aspartate aminotransferase (AST) > 3 × upper limit of normal
(ULN) or total bilirubin > 2 × ULN.

- Participant is of childbearing potential, unless willing to ensure that they or their
partner use a highly effective method of birth control (e.g., combined [estrogen and
progestogen containing] hormonal contraception associated with inhibition of ovulation
[oral, intravaginal, or transdermal], progestogen-only hormonal contraception
associated with inhibition of ovulation [oral, injectable, or implantable],
intrauterine devices/hormone-releasing systems, bilateral tubal occlusion,
vasectomized partner, sexual abstinence) during the trial and for 3 months thereafter.

- Pregnant (positive pregnancy test) or lactating

- Received an IMP within the 3 months prior to screening

- Participant has been taking felbamate for less than 1 year prior to screening.

- Currently using or has used recreational or medicinal cannabis, cannabinoid-based
medications (including Sativex®), or cannabidiol oral solutions (including CBD-OS
[GWP42003-P]) within the 3 months prior to screening and is unwilling to abstain for
the duration of the trial

- Participant has a positive delta-9-tetrahydrocannabinol (THC) test at screening.

- Any other systemic dysfunction (e.g., gastrointestinal, renal, respiratory) or
significant disease or disorder which, in the opinion of the investigator, may either
put the participant at risk because of participation in the trial, may influence the
result of the trial, or the participant's ability to participate in the trial

- Any abnormalities identified following a physical examination of the participant that,
in the opinion of the investigator, would jeopardize the safety of the participant if
she took part in the trial

- Participant has been previously randomized into this trial.

- Participant has travel outside the country of residence planned during the trial.

Age minimum: 2 Years
Age maximum: 18 Years
Gender: Female
Health Condition(s) or Problem(s) studied
Rett Syndrome
Drug: GWP42003-P
Drug: Placebo
Primary Outcome(s)
Rett Syndrome Behaviour Questionnaire (RSBQ) [Time Frame: 24 weeks]
Secondary Outcome(s)
9-items Motor Behavioral Assessment (MBA-9) [Time Frame: 24 weeks]
Children's Sleep Habits Questionnaire (CSHQ) [Time Frame: 24 weeks]
Clinical Global Impressions - Improvement (CGI-I) [Time Frame: 24 weeks]
Clinician Global Impressions - Severity Scale (CGI-S) [Time Frame: 24 weeks]
RSBQ subscales [Time Frame: 24 weeks]
Secondary ID(s)
Source(s) of Monetary Support
Please refer to primary and secondary sponsors
Secondary Sponsor(s)
Ethics review
Results available:
Date Posted:
Date Completed:
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