Psilocybin in Adults With and Without Autism Spectrum Disorder

Brief Summary

This study will test the hypothesis that brain systems are differentially regulated by serotonin in individuals with and without Autism Spectrum Disorder.

Intervention / Treatment

Case-Control comparison using repeated-measures cross-over design. Each participant receives each one of the three pharmacological probes in separate visits (i.e., placebo, psilocybin low dose and psilocybin higher dose), with the order of administration being pseudorandomized (to prevent order effects).
  • Psilocybin 5 mg (DRUG)
    Partial Serotonin (5HT) 1A/2A Receptor Agonist Psilocybin
  • Psilocybin 2 mg (DRUG)
    Partial Serotonin (5HT) 1A/2A Receptor Agonist Psilocybin
  • Placebo (DRUG)
    Inactive placebo

Condition or Disease

  • Autism Spectrum Disorder

Phase

  • Not Applicable
  • Study Design

    Study type: INTERVENTIONAL
    Status: Recruiting
    Study results: No Results Available
    Age: 18 Years to 60 Years
    Enrollment: 70 (ESTIMATED)
    Allocation: Randomized
    Primary Purpose: Basic Science

    Masking

    Participants and investigators are blinded to the drug condition

    DOUBLE:
    • Participant
    • Investigator

    Clinical Trial Dates

    Start date: Dec 01, 2022 ESTIMATED
    Primary Completion: Dec 01, 2024 ESTIMATED
    Completion Date: Dec 01, 2024 ESTIMATED
    Study First Posted: Dec 14, 2022 ACTUAL
    Last Updated: Dec 06, 2022

    Sponsors / Collaborators

    Lead Sponsor: King's College London
    Responsible Party: N/A

    To do this, the brain response to two single acute doses of partial serotonin (5HT)1A/2A receptor agonist psilocybin (COMP360) relative to a single dose of placebo (baseline serotonin activity) will be compared in healthy autistic and non-autistic adults.

    Brain function will be assessed using a range of MRI (fMRI and MRS), EEG and sensory tasks. Unimodal and multimodal analyses will be conducted.

    Please note that this study uses psilocybin as a probe of the serotonin system in a Case-Control science study and, following Scope protocol review, the U.K. MHRA confirmed that it is not a 'Clinical Trial of an Investigational Medicinal Product' (IMP) as defined by the EU Directive 2001/20/EC.

    Participant Groups

    • Dose order: Placebo, Psilocybin 2mg, Psilocybin 5mg

    • Dose order: Psilocybin 2mg, Placebo, Psilocybin 5mg

    • Dose order: Psilocybin 2mg, Psilocybin 5mg, Placebo

    Eligibility Criteria

    Sex: All
    Minimum Age: 18
    Maximum Age: 60
    Age Groups: Adult
    Healthy Volunteers: Yes

    Inclusion Criteria:

    For all participants:

    * Calendar age above 18 years
    * Working knowledge of English
    * Able to give informed consent
    * Not pregnant or breastfeeding
    * Individuals should be in good physical health, prescription medication free during the 2-week period preceding a study visit. However, occasional use of over-the-counter medication (e.g. painkillers) on an as needed basis (and not on the day of study visit) may be permitted. In addition, regular prescription medication (use of a stable dose over the two months preceding participation) with a drug that does not affect 5HT directly may be permitted. Also permitted is topical medication without systemic exposure

    For individuals with ASD:

    * Diagnosis of ASD by recognised clinical service supported by the Autism Diagnostic Interview-Revised (ADI-R) if a relative is available. Current symptom level assessed using the Autism Diagnostic Observation Schedule (ADOS-2)

    Exclusion Criteria:

    For all participants:

    * History of allergy/idiosyncrasy to psilocybin or chemically related compounds or excipients which may be employed in the study or to any other drug used in the past
    * Clinically relevant history or presence of any medical disorder, potentially interfering with this study
    * Clinically relevant abnormality at screening as judged by the investigator
    * History of or current abuse of drugs (including prescription medication) or alcohol or solvents
    * Participation in a research study involving a pharmacological probe or drug trial within last month
    * Subjects with current epilepsy, seizures or episodes of unexplained and unprovoked loss of consciousness
    * Anyone with a history or examination which indicates laboratory testing is needed will be excluded from the study
    * Intelligence Quotient below 70
    * Currently taking prescription medications of propranolol or pindolol
    * Individuals with major mental illness
    * Individuals who have a current or past history of meeting diagnostic criteria for schizophrenia or other psychotic disorders or bipolar I or II disorder

    Reproductive safety:

    * Pregnancy or breastfeeding (is a routine exclusion for research MRI scanning)
    * Female study participants must be willing to use one form of highly effective non-hormonal contraception for one week after study drug administration. This would include a vasectomised partner (sole partner), tubal occlusion, intrauterine system \[IUS\]/hormonal coil or copper containing intrauterine device or copper containing IUD, or true abstinence (when this is in line with the preferred and usual lifestyle of the subject). Women should have been stable on their chosen method of birth control for a minimum of 2 months before entering the study. Participants must agree to undergo a pregnancy test prior to each administration of study drug

    For individuals with ASD:

    ASD caused by a known genetic syndrome, e.g. Fragile X, 22q11 deletion syndrome.

    Currently treated for epilepsy

    This clinical trial is recruiting

    Are you interested in participating in this trial or others? We'd love to help.

    Primary Outcomes
    • Comparing whole brain blood-oxygen-level-dependent (BOLD) activation (institutional units) during the resting state in cases and controls when the serotonin system is activated by a single oral dose of psilocybin (COMP360) versus the placebo condition.

    • Case-control comparison of task-free EEG by time-frequency analysis during placebo and when serotonin system is activated with psilocybin.

    • Case-control comparison of EEG Evoked Potentials in response to visual stimulation during placebo and when serotonin system is activated with psilocybin.

    • Case-control comparison of EEG Event Related Potentials in response to auditory tones during placebo and when serotonin system is activated with psilocybin.

    Secondary Outcomes
    • Quantification and case-control comparison of brain metabolites relevant to regulation of excitation and inhibition (focus on Glx, GABA, GSH) using proton magnetic resonance spectroscopy when serotonin system is 'at rest' (placebo) and when activated by psilocybin.

    Other Outcomes
    • 5-Dimensional altered states of consciousness (5D-ASC) used for Case-control comparison of subjective effects intensity at placebo and when serotonin system activated with psilocybin

    More Details

    NCT Number: NCT05651126
    Other IDs: IRAS: 292281; REC: 21/LO/0795
    Study URL: https://clinicaltrials.gov/study/NCT05651126
    Last updated: Sep 29, 2023