Psilocybin in Adults With and Without Autism Spectrum Disorder (PSILAUT)

This interventional study (n=70), led by King’s College London, aims to investigate the modulation of serotonin pathways using psilocybin (2-5mg) in adults with and without Autism Spectrum Disorder (ASD; Autism).

The trial, which is estimated to enrol 70 participants, employs a randomised crossover design. Each participant receives three pharmacological probes in separate visits: placebo, psilocybin 2 mg, and psilocybin 5 mg.

The study investigates brain activation and connectivity response to serotonergic stimulation using functional magnetic resonance imaging (fMRI), task-free electroencephalography (EEG), sensory tasks, and magnetic resonance spectroscopy. The primary outcome measures include assessing whole brain blood-oxygen-level-dependent (BOLD) activation during resting state, task-free EEG analysis and EEG-evoked potentials during visual and auditory stimulation.

The trial started in December 2022 and is expected to complete in December 2024. Eligible participants are adults aged 18 to 60, and the study is open to both individuals with ASD and those without. The trial is not a ‘Clinical Trial of an Investigational Medicinal Product’ according to the UK MHRA. Contact information for study inquiries is provided, with Professor Grainne McAlonan as the primary contact.

The study is also published on the site of Compass.

The study protocol can be found here.

Topic Autism
Compound Psilocybin Placebo
Country United Kingdom
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Trial Details



Trial Number

Sponsors & Collaborators

King's College London
The Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King's College London is one of Europe's top centres for mental health and related neurosciences research.

COMPASS Pathways
COMPASS Pathways is a publicly listed company (NASDAQ) that is developing psilocybin for treatment-resistant depression (TRD) for which it has completed a successful Phase IIb trial. COMPASS is one of the largest psychedelic companies and has received substantial investment from atai.

South London and Maudsley NHS Foundation Trust
The South London and Maudsley NHS Foundation Trust provide the widest range of NHS mental health services in the UK. The trust has recently expanded its research into psychedelic therapies.

Data attribution

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