Psilocybin Whole Mushroom for the Treatment of Obsessive-compulsive Disorder. (Mushroom-OCD)

May 11, 2026 updated by: Francisco A Moreno

A Randomized Double-masked Dose-controlled Trial to Assess the Tolerability, Safety, Subjective Experience, and Efficacy of Repeated Administration of Three Different Doses of Psilocybin Whole Mushroom for the Treatment of Obsessive-compulsive Disorder.

The study tries to improve our treatments for people who have obsessive-compulsive disorder (OCD) by testing psilocybin, a mind altering drug that changes activity in brain areas involved in OCD. 30 patients with moderate or more severe OCD who are not taking mind altering medications or street drugs will participate in a 12 week study. Participants will be assigned (by luck of the draw) to take a low, medium, or high dose whole psilocybin mushroom contained in three chocolate pieces, prepared for this study by the Scottsdale Research Institute.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Participants will come to the University of Arizona CATS Research Unit in Tucson for assessment, if they are found to be fit for study participation, they will be scheduled for a preparation session with a study therapist and then will participate in a dosing session when they will ingest three pieces of chocolate containing psilocybin mushroom. They will answer questions of how they are feeling, and will be monitored for safety by two study staff members, and their vital signs will be checked every hour on the day they receive the study drug. The will be sent home with a responsible adult selected by the patient after they are felt to be safe once the effects of the drug have resolved. Participants will receive four different doses separated by about three weeks. After they complete the treatment phase, they will be contacted monthly for follow up assessment of efficacy, and safety.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
30

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

  • Name: Study Coordinator
  • Phone Number: (520) 626-4804

Study Locations

  • United States
    • Arizona
      • Tucson, Arizona, United States, 85724
        • Recruiting
        • The Clinical and Translational Sciences Research Center
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Aged 18 years old, and older
  • Have OCD (DSM-5) based on diagnostic interview using the Structured Clinical Interview for DSM-5 Research Version (SCID).
  • At least moderate severity: Yale-Brown Obsessive Compulsive Scale (YBOCS) score ≥16.
  • Failed at least one adequate trial of guideline concordant treatment.
  • Considered safe for independent living

  • Subjects must discontinue use of any of the following prescription or over the counter (OTC) products or nutritional supplements at least two weeks prior to initiating double-blind treatment:

    • Monoamine oxidase (MAOI), UGT1A10, and UGT1A9 inhibitors

    • Other active OCD treatments (cognitive behavioral therapy [CBT] or other psychotherapy; electrical or magnetic device treatments; pharmacological treatments such as antidepressant medications (e.g., SSRIs, SNRIs, MAOIs, TCAs, 5HT2 blockers, NERIs, etc.), lithium, antipsychotic drugs, 5-HT2 antagonists such as pimavanserin, and glutamatergic acting medications)

      * Note that fluoxetine must be discontinued at least 6 weeks prior to initiating double-blind treatment.

    • 5HT2 agonists (e.g., efavirenz, lorcaserin), which may alter the response to psilocybin
    • Serotonin-acting dietary supplements (e.g., 5-hydroxy-tryptophan, St. John's wort) due to potential for interaction with psilocybin and increased safety risks

Exclusion Criteria:

  • Concurrent active substance use disorder, or a personal history of psychosis.
  • History of psychosis among first degree relatives as determined by the Family Interview for Genetic Studies (FIGS)32
  • Medical illness based on physical examination and routine blood testing that may complicate cardiovascular safety or drug metabolism or excretion. Examples include: 1) Cardiovascular conditions: lifetime history of stroke, lifetime myocardial infarction, uncontrolled hypertension (resting blood pressure >140/90 mmHg), tachycardia (resting heart rate >100 beats per minute), elongated QT interval corrected by Fridericia's formula (QTcF; interval >450 msec), participants with existing valvular heart disease, or clinically significant arrhythmia (<1 year prior to signing the ICF); 2) Metabolic conditions: subjects with diabetes should have a stable diabetes treatment regimen and no history of diabetic ketoacidosis, hyperglycemic coma, or no hypoglycemic episodes with glucose below 54 mg/dL in the 3 months prior to baseline, and fasting glucose >70 mg/dL at baseline; 3) Severe renal impairment: eGFR <45 mL/min/1.73 m²); and Liver failure: Child-Pugh Classes B and C.
  • Unstable Chronic Obstructive Pulmonary Disease (COPD) or severe sleep apnea
  • Clinically significant renal or hepatic impairment, per clinical judgment of a study physician
  • EKG QTc ≥ 450 msec
  • Psychiatric comorbidity that may represent an acute risk to their own or other's safety, including history of bipolar disorder (I or II) in the participant or first degree relative, as well as any family history of psychosis.
  • Subjects cannot require any sedative, narcotic, or neuroleptic medications on a regular basis. Any of these medications they have taken should have been stopped long enough in the past to allow for their elimination and safe withdrawal prior to starting administration of the study drug. The specific time required will be dependent on the medication the patient was previously receiving.
  • Participants who are pregnant, breastfeeding, planning a pregnancy, or planning to donate sperm within three months post-last study drug administration.
  • Participants of childbearing potential or participants with partners of childbearing potential who engage in intercourse which could result in pregnancy are unwilling/unable to practice medically acceptable highly effective birth control (double barrier, oral and injectable pharmacological contraceptives, or surgical such as vasectomy or bilateral tubal occlusion) during the study and up to three months after the last study drug administration.
  • Suicide attempt within the 12 months prior to enrollment
  • Any condition for which MRI is contraindicated, at the discretion of a study investigator or the MRI technician, including: Pacemakers and defibrillators; artificial heart valves which are not MRI safe; any metal in head, spinal cord, eyes or chest; any electrical devices such as cochlear implants, nerve stimulators, deep brain stimulators, gastric pacemaker, or insulin or pain pumps; aneurysm clips; ferrous (i.e. non titanium alloy) implants in any part of the body.

  • Use within the week prior to screening of drugs of abuse as listed in the current US DOJ DEA Drugs of Abuse Resource Guide, including:

    • Cannabinoids (marijuana, synthetic cannabinoids)
    • Simulants (amphetamine, cocaine, methamphetamine, methylphenidate, modafinil)
    • Opioids (natural and synthetic),
    • Sedatives (benzodiazepines, barbiturates, GHB, zolpidem, zaleplon, zopiclone)
    • Hallucinogens (DMT, ibogaine, LSD, MDMA, psilocybin, psilocin, PSP)
  • Weight below 45kg
  • Allergy or significant intolerance to chocolate or cocoa

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Low dose 10 mg
Whole dried psilocybin mushroom containing 10 mg of psilocybin will be mixed in a chocolate matrix and administered to the patient.
Drug: Psilocybin 10 mg
Oral administration of whole dried psilocybin mushrooms contained in a chocolate matrix.
Experimental: Middle dose 20 mg
Whole dried psilocybin mushroom containing 20 mg of psilocybin will be mixed in a chocolate matrix and administered to the patient.
Drug: Psilocybin 20 mg
Oral administration of whole dried psilocybin mushrooms contained in a chocolate matrix.
Experimental: High dose 30 mg
Whole dried psilocybin mushroom containing 30 mg of psilocybin will be mixed in a chocolate matrix and administered to the patient.
Drug: Psilocybin 30 mg
Oral administration of whole dried psilocybin mushrooms contained in a chocolate matrix.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Yale Brown Obsessive Compulsive Scale
Time Frame: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).
Clinician rating scale to determine severity of OCD symptoms. Scores vary from 0 to 40. Higher scores represent greater severity of OCD symptoms.
Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).
Adverse Event (AE) Tracking log
Time Frame: Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).
The Adverse Event tracking log will collect information on adverse health events reported throughout the research study.
Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).
Visual Analogue Scale (VAS)
Time Frame: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Scale 0 (no symptoms at all) to 100 (maximum symptom severity)
Self-reported measure of intensity or frequency of pain or other various symptoms
Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Scale 0 (no symptoms at all) to 100 (maximum symptom severity)

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
World Health Organization's quality of life assessment (WHOQOL-BREF)
Time Frame: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).
A 26-item psychometric questionnaire to measure quality of life and functional ability. Raw scores are converted to transformed scores in four health related domains. Higher scores represent higher quality of life.
Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase).
Short form health survey (SF-36)
Time Frame: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Functionality scales are transformed to range from 0 to 100 with 0 being maximal disability and 100 being no disability.
Subject self-reporting health survey to monitor and assess functional impairment
Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Functionality scales are transformed to range from 0 to 100 with 0 being maximal disability and 100 being no disability.
Columbia-Suicide Severity Rating Scale (C-SSRS)
Time Frame: Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Individuals with positive ideation or behavior scores can be categorized into low, moderate or high risk of suicide.
A suicide risk assessment tool for prospective monitoring of suicidal ideation and behavior.
Baseline, Weekly for 12 weeks (Treatment phase), and Monthly for 12 month (Follow up phase). Individuals with positive ideation or behavior scores can be categorized into low, moderate or high risk of suicide.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Francisco A Moreno

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Arizona Biomedical Research Commission (ABRC)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Francisco Moreno, MD, University of Arizona

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
May 18, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 1, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
January 1, 2029

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 22, 2025

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 8, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 16, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 12, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 11, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
May 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 00005573

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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