A study in healthy male volunteers to investigate how the test medicine COMP360 [14C]-psilocybin is taken up, broken down and removed from the body

This Phase I, open-label trial (n=6) investigates how psilocybin (COMP360; 10mg) is absorbed, distributed, metabolised, and excreted in healthy male volunteers aged 30-55.

The study, conducted by Compass at a pharmaceutical testing facility in Nottingham, aims to assess the safety and breakdown of a radiolabelled version of psilocybin, a psychedelic compound being developed for treatment-resistant depression.

Participants will receive a single oral dose of COMP360 and remain in the clinic for up to 10 nights, during which blood, urine, and faeces samples will be collected to track the drug’s movement and elimination from the body. Psychological effects will be monitored, and therapist support will be provided. Volunteers will be exposed to a controlled amount of radiation (3.8 mSv, comparable to 2.5 head CT scans). The study started in July 2024 and was completed in January 2025.

Topic Healthy Subjects Safety
Compound Psilocybin
Country United Kingdom
Visit trial
Status Completed
Results Published No
Start date 18 July 2024
End date 23 January 2025
Phase Phase I
Design Open
Type Interventional
Generation Second
Participants 6
Sex Male
Age 30- 55
Therapy No

Trial Details

The Sponsor is developing the test medicine, COMP360, for the potential treatment of treatment-resistant depression. Depression is a common mental health problem that can cause people to experience low mood, loss of motivation or pleasure, feelings of guilt or low self-worth, disturbed sleep, changes in appetite, low energy and concentration. Patients with treatment-resistant depression see no improvement in their symptoms with standard depression medication. In this study, healthy volunteers will be given a single dose of test medicine to find out how the body breaks down and gets rid of the test medicine. The test medicine will be ‘radiolabelled’ - it will contain a small amount of radioactivity (Carbon-14) - so that we can track it in the body. This study on healthy volunteers aims to answer whether the test medicine causes any important side effects, how much test medicine enters the bloodstream and how quickly the body gets rid of it.

Trial Number ISRCTN37167117

Sponsors & Collaborators

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.

Data attribution

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