PsilOCD: A Pharmacological-Challenge Feasibility Study

This single-group assignment trial (n=20) assesses the impact of psilocybin (10mg, 2x) on cognitive inflexibility and neural plasticity in individuals with obsessive-compulsive disorder (OCD).

Participants, aged between 20 to 65 years, diagnosed with OCD according to DSM-5 criteria, will receive up to 10mg of psilocybin on two separate dosing days spaced four weeks apart. The dosing will occur under medical supervision with psychological support from experienced therapists. Before and after each session, participants will engage in virtual preparation and integration sessions led by their therapists. Cognitive tasks will be administered in the days following each dosing session, along with acute post-dosing EEG recordings and blood samples. OCD symptoms will also be assessed periodically throughout the trial by an external blinded psychiatrist.

This interventional study is led by Imperial College London and commenced on October 28, 2022. The primary completion is estimated by June 30, 2024, with the study completion estimated by July 30, 2024. It aims to enrol 20 participants and is part of Phase I clinical trials.

The study protocol can be found here.

Topic Obsessive-Compulsive Disorder
Compound Psilocybin
Country United Kingdom
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Trial Details



Trial Number

Sponsors & Collaborators

Imperial College London
The Centre for Psychedelic Research studies the action (in the brain) and clinical use of psychedelics, with a focus on depression.

Data attribution

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