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Psilocybin for Treatment of Obsessive Compulsive Disorder

Psilocybin for Treatment of Obsessive Compulsive Disorder

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03300947
Acronym
PSILOCD
Enrollment
15
Registered
2017-10-04
Start date
2019-01-02
Completion date
2023-12-30
Last updated
2024-08-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Obsessive-compulsive Disorder (OCD)

Brief summary

This study will evaluate whether psilocybin, a hallucinogenic drug, improves symptoms of obsessive compulsive disorder (OCD), whether it is safely tolerated as treatment of OCD, and will investigate the mechanisms by which it works.

Detailed description

The study seeks to improve our ability to treat and improve the lives of people who have obsessive-compulsive disorder (OCD) by exploring the benefits of psilocybin, a mind-altering drug that changes activity in brain areas believed to be involved in OCD. Anecdotal reports and results from previous research support this idea. This two-phase study will enroll patients with symptomatic OCD who are not taking mind-altering medications or street drugs. During Phase One, neither participants nor the investigators will know which drugs or doses are administered. This information will be available if it is medically necessary to reveal which drugs and doses were administered. Five subjects in each group will receive study drug a total of four times, separated by one week. During Phase Two, participants will not know which drugs or doses they receive, but the investigators will know. All participants will receive psilocybin at some point during study participation. Participants will be randomly assigned to one of the following groups: 1. Low dose (100 µg/kg) psilocybin, 2. High dose (300 µg/kg) psilocybin, or 3. Lorazepam (1 mg), a calming medication. Lorazepam is used often for anxiety and will be used to mask which drug participants receive. Participants will spend approximately 12 hours at the research site under observation during each visit, until they are free of the mind-altering effects of the drug and are determined by the psychiatrist to be safe to go home accompanied by a responsible adult. The effects of low versus high doses, and the additive effects of repeated doses will be analyzed and will be compared to the effects of lorazepam.

Interventions

DRUGPsilocybin 100 mcg/kg

Psilocybin belongs to the class of hallucinogen or psychedelic drugs. It is one of the major psychoactive components in mushrooms of the Psilocybe genus (magic mushrooms).

DRUGPsilocybin 300 mcg/kg

Psilocybin belongs to the class of hallucinogen or psychedelic drugs. It is one of the major psychoactive components in mushrooms of the Psilocybe genus (magic mushrooms).

A medication used to treat anxiety belonging to a class of drugs known as benzodiazepines, which act on the central nervous system to produce a calming effect. This drug works by enhancing the effects of a certain natural chemical in the body (GABA).

Sponsors

University of Arizona
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Masking description

Phase One: Double blind (both participant AND researchers (In room Care Provider, Investigators, Blinded Outcomes Assessor) Phase Two: Single blind (Participant and Blinded Outcomes Assessor)

Intervention model description

All participants will be randomly assigned to administration of low dose (100 µg/kg) psilocybin, High dose (300 µg/kg) psilocybin, or Lorazepam (1 mg). Eight different sessions divided in two phases will ensure all subjects are exposed to psilocybin at some point during the study in a blinded fashion.

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

* Have moderate to severe OCD (DSM-5) after diagnostic interview using the Structured Clinical Interview for DSM-5 Research Version (SCID-R). * Failed at least one adequate attempted routine care treatment. * Considered safe for independent living

Exclusion criteria

* Concurrent psychosis, active substance use disorder, or a personal history of psychosis. * Medical illness based on physical examination and routine blood testing that may complicate cardiovascular safety or drug metabolism or excretion, such as uncontrolled hypertension, severe cardiac disease, or kidney or liver failure. * Unstable Chronic Obstructive Pulmonary Disease (COPD) or severe sleep apnea * Psychiatric comorbidity that may represent an acute risk to their own or others' safety. * Subjects may not be using antidepressant medication for OCD for at least two weeks before receiving study drug, and they 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. * Women who are pregnant, breastfeeding, or unwilling/unable to practice medically acceptable birth control during the study. * Allergy to lorazepam.

Design outcomes

Primary

MeasureTime frameDescription
Treatment-phase effects on Obsessive-Compulsive symptom severityweekly Y-BOCS rating prior to ingestion of study drug on Week 1 through 8, and week 9 (follow up week 1)Prospective Assessment of YBOCS (Yale-Brown Obsessive Compulsive Scale) score comparing each psilocybin dose and active placebo (Lorazepam).

Secondary

MeasureTime frameDescription
Duration of Effects on Obsessive-Compulsive symptom severityFollow-up assessments will be conducted weekly over the phone weekly (± 3 days) for one month after last dose, monthly (± 7 days) for three months beginning 28 days after last dose, and then once at 6 months after last dose (± 7 days).Prospective Naturalistic Assessment of YBOCS (Yale-Brown Obsessive Compulsive Scale) after repeated administration of study drug.
Long Term Incidence and Duration of Treatment Emergent Psychiatric Adverse EventsFollow-up assessments will be conducted weekly over the phone (± 3 days) for one month after last dose, monthly (± 7 days) for three months beginning 28 days after last dose, and then once at 6 months after last dose (± 7 days).Prospective Assessment with SCID-I (Structured Clinical Interview for DSM-5 Disorders) psychotic screening tool will assess for onset of psychopathology or hallucinogen induced disorders after repeated use.
Changes in the magnitude of Error Related Negativity (an electroencephalographic biomarker of OCD) assessed by Error-related negativity (voltage) and mid-frontal theta power (time-frequency approach)Baseline, and 9-10 hours after ingestion of study dose 1, 4, and 8.Prospective Assessment of Error Related brain activity comparing each psilocybin dose and active placebo (Lorazepam).
Acute Incidence of Treatment Emergent Adverse EventsAt 0, and 24 hours after blinded medication ingestionProspective active inquiry of adverse events with the SAFTEE-GI (Systematic Assessment For Treatment Emergent Events-General Inquiry) comparing each psilocybin dose and active placebo (Lorazepam)
Prospective Clinician-Rated Assessment of Depression SymptomsBaseline, 4 weeks, 8 weeks, and during the follow-up phase (weekly for one month after last dose, monthly for three months beginning 28 days after last dose, and then once at 6 months after last doseProspective Assessment of Montgomery-Asberg Depression Rating Scale (MADRS) Score comparing each psilocybin dose and active placebo (Lorazepam).
Changes in functional connectivity: 1) between the Caudate Nucleus (CN) and Orbital Frontal Cortex (OFC); 2) within the default mode network (DMN).Imaging at baseline, and 9-10 hours post ingestion on weeks 1, 4, and 8. YBOCS at baseline and 8 hours after ingestion at weeks 1, 4, and 8.Prospective Assessment of Functional Connectivity in CN and OFC and in DMN comparing each psilocybin dose and active placebo (Lorazepam). Also examining whether magnitude of symptom reduction is related to changes in functional connectivity.
Prospective Self-Assessment of Depression SymptomsBaseline, 24 hours after each dose during 8 week active phase, and during the follow-up phase (weekly for one month after last dose, monthly for three months beginning 28 days after last dose, and then once at 6 months after last dose.Prospective Assessment of Quick Inventory of Depressive Symptomatology (QIDS) Score comparing each psilocybin dose and active placebo (Lorazepam).

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 15, 2026