Role of the Serotonin 2A Receptor in Psilocybin-induced Altered States of Consciousness (NCT06796361) | Clinical Trial Compass
RecruitingPhase 1
Role of the Serotonin 2A Receptor in Psilocybin-induced Altered States of Consciousness
Switzerland16 participantsStarted 2025-04-21
Plain-language summary
Psilocybin (active compound of "magic mushrooms") is a prototypical psychedelic substance that acts via agonism on serotonin (5-HT) 2A receptors. Psilocybin is rapidly metabolized into its active metabolite psilocin. Psilocybin is currently under investigation as potential treatment for various neuropsychiatric disorders. Psilocybin is also widely used for recreational purposes and as research tool in neuroscience. Besides its current clinical development, a clear characterization of the dose-response relationship of psilocybin is lacking. With the present study the investigators aim to close this knowledge gap by administering low (5mg) to high (40mg) single doses of psilocybin to healthy participants. Besides its agonism on 5-HT2A receptors, psilocin also binds to other receptors and inhibits serotonin transporters (SERT). To this data only few studies have investigated these effects and never at a high dose.
Who can participate
Age range
25 Years – 75 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Age between 25 and 75 years.
. Sufficient understanding of the German language.
. Understanding the procedures and the risks that are associated with the study.
. Participants must be willing to adhere to the protocol and sign the consent form.
. Participants must be willing to refrain from taking illicit psychoactive substances during the study (not including cannabis).
. Participants must be willing not to drive a traffic vehicle or to operate machines within 48 h after substance administration.
. Women of childbearing potential must be willing to use effective birth-control throughout study participation
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
5 dimensions of altered state of consciousness (5D-ASC) total OAV score
Timeframe: 10 hours after substance administration
. Chronic or acute medical condition, including a history of seizures.
. Body mass index 18-29.9 kg/m2
. Current or previous major psychiatric disorder (e.g. psychotic disorders, mania / hypomania, anxiety disorders).
. Psychotic or bipolar disorder in first-degree relatives, not including psychotic disorders secondary to an apparent medical reason, e.g., brain injury, dementia, or lesions of the brain.
. Hypertension (SBP\>140/90 mmHg) or hypotension (SBP\<85 mmHg)
. Psychedelic substance use (with the exception of cannabis) more than 20 times or any time within the previous two months
. Pregnant or nursing women.
. Participation in another clinical trial (currently or within the last 30 days).