Shifting Brain Excitation-Inhibition Balance in Autism Spectrum Disorder
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ClinicalTrials.gov Identifier: NCT03537950 |
Recruitment Status : Unknown
Verified May 2018 by Dr Grainne McAlonan, King's College London.
Recruitment status was: Active, not recruiting
First Posted : May 25, 2018
Last Update Posted : May 25, 2018
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Autism Spectrum Disorder | Drug: PLC Drug: CBD Drug: CBDV | Not Applicable |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 38 participants |
Allocation: | Randomized |
Intervention Model: | Crossover Assignment |
Intervention Model Description: | Repeated-measures cross-over study, where each subject received each of three pharmacological probes once (order of drug administration was pseudorandomised) |
Masking: | Double (Participant, Investigator) |
Masking Description: | Participants and investigators were blinded to the drug condition. |
Primary Purpose: | Basic Science |
Official Title: | Shifting Brain Excitation-Inhibition Balance Through the Endocannabinoid System in Men With Autism Spectrum Disorder (ASD) and in Healthy Controls |
Actual Study Start Date : | August 22, 2016 |
Actual Primary Completion Date : | February 16, 2017 |
Estimated Study Completion Date : | April 27, 2019 |

Arm | Intervention/treatment |
---|---|
Experimental: PLC, CBD, CBDV
Dose order: PLC, CBD, CBDV
|
Drug: PLC
Single oral dose of PLC.
Other Name: Placebo Drug: CBD Single oral dose of cannabidiol (CBD) - 600mg.
Other Name: Cannabidiol Drug: CBDV Single oral dose of cannabidivarin (CBDV) - 600mg.
Other Name: Cannabidivarin |
Experimental: PLC, CBDV, CBD
Dose order: PL, CBDV, CBD
|
Drug: PLC
Single oral dose of PLC.
Other Name: Placebo Drug: CBD Single oral dose of cannabidiol (CBD) - 600mg.
Other Name: Cannabidiol Drug: CBDV Single oral dose of cannabidivarin (CBDV) - 600mg.
Other Name: Cannabidivarin |
Experimental: CBD, PLC, CBDV
Dose order: CBD, PLC, CBDV
|
Drug: PLC
Single oral dose of PLC.
Other Name: Placebo Drug: CBD Single oral dose of cannabidiol (CBD) - 600mg.
Other Name: Cannabidiol Drug: CBDV Single oral dose of cannabidivarin (CBDV) - 600mg.
Other Name: Cannabidivarin |
Experimental: CBD, CBDV, PLC
Dose order: CBD, CBDV, PLC
|
Drug: PLC
Single oral dose of PLC.
Other Name: Placebo Drug: CBD Single oral dose of cannabidiol (CBD) - 600mg.
Other Name: Cannabidiol Drug: CBDV Single oral dose of cannabidivarin (CBDV) - 600mg.
Other Name: Cannabidivarin |
Experimental: CBDV, PLC, CBD
Dose order: CBDV, PLC, CBD
|
Drug: PLC
Single oral dose of PLC.
Other Name: Placebo Drug: CBD Single oral dose of cannabidiol (CBD) - 600mg.
Other Name: Cannabidiol Drug: CBDV Single oral dose of cannabidivarin (CBDV) - 600mg.
Other Name: Cannabidivarin |
Experimental: CBDV, CBD, PLC
Dose order: CBDV, CBD, PLC
|
Drug: PLC
Single oral dose of PLC.
Other Name: Placebo Drug: CBD Single oral dose of cannabidiol (CBD) - 600mg.
Other Name: Cannabidiol Drug: CBDV Single oral dose of cannabidivarin (CBDV) - 600mg.
Other Name: Cannabidivarin |
- Brain biochemistry response to pharmacological stimulation [ Time Frame: In the months 1-2 following the last day of scanning. ]
The measure of brain biochemistry response to PLC, CBD, and CBDV includes the following:
Assessment of the ratio of brain excitation and inhibition (measured as the balance of excitatory and inhibitory neurotransmitters) using using proton magnetic resonance spectroscopy [1H]MRS.
- Measurement of low frequency brain activity using resting state fMRI [ Time Frame: In the months 3-4 following the last day of scanning ]In the third and fourth month following the day of the last scan, we will measure whole brain low frequency brain activity using resting state functional magnetic resonance imaging. Measure of activity: fractional amplitude of low frequency fluctuations.
- Measurement of brain functional connectivity using resting state fMRI [ Time Frame: In the months 5-6 following the last day of scanning ]In the fifth and sixth month following the day of the last scan, we will measure whole brain resting state functional connectivity using resting state functional magnetic resonance imaging. Measure of connectivity: correlation between pairs of regions.

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Ages Eligible for Study: | 18 Years to 50 Years (Adult) |
Sexes Eligible for Study: | Male |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- men
- pass diagnostic threshold for ASD on the ADI-R (if informant is available)
- currently symptomatic on ADOS
- age 18-50 years
- can give informed consent
- IQ>70 (on a standard instrument such as WASI)
- medication-free in the month preceding participation (but regular medication with drug, which does not affect glutamate or GABA directly may be permitted)
- willing to provide urine samples to screen for use of illicit substances prior to each scan
Exclusion Criteria:
- IQ<70
- history of psychosis, co-morbid major mental illness, significant physical illness (heart disease, high blood pressure, seizures)
- habitual substance misuse (including alcohol)
- known allergy to cannabis
- ASD caused by a known genetic syndrome e.g. Fragile X or 22q11 deletion syndrome,
- past/present treatment for epilepsy
- Women will be excluded from this pilot study to reduce heterogeneity in a small sample; avoid the issues around exposing women of reproductive age to a drug; and because pregnancy is a routine exclusion criteria for research MRI. Lastly, ASD is more common in men.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03537950
United Kingdom | |
King's College London | |
London, United Kingdom, SE5 8AF |
Principal Investigator: | Grainne McAlonan, PhD | King's College London |
Responsible Party: | Dr Grainne McAlonan, Deputy head of department, King's College London |
ClinicalTrials.gov Identifier: | NCT03537950 |
Other Study ID Numbers: |
HR15-162744 |
First Posted: | May 25, 2018 Key Record Dates |
Last Update Posted: | May 25, 2018 |
Last Verified: | May 2018 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Cannabidiol Cannabidivarin E-I balance pharmacological imaging |
Autistic Disorder Autism Spectrum Disorder Child Development Disorders, Pervasive Neurodevelopmental Disorders |
Mental Disorders Cannabidiol Anticonvulsants |