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Psychedelic Therapy

Psilocybin (25 mg) for Major Depressive Disorder (SYNVEST Trial)

Phase 2
Waitlist Available
Led By Muhammad Ishrat Husain, MBBS, MD
Research Sponsored by Centre for Addiction and Mental Health
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
1. Adults 18 to 65 years old;
2. Must be deemed to have capacity to provide informed consent;
Timeline
Screening 3 weeks
Treatment Varies
Follow Up 24 months
Awards & highlights

Summary

Limit: 5000 characters. Psilocybin, the chemical component of "magic mushrooms", has been administered with psychotherapy in several randomized clinical trials (RCTs) showing large and sustained antidepressant effects. In healthy volunteers, the psychedelic effects of psilocybin have been shown to be blocked by administration of certain medications such as risperidone. The purpose of this study is to use an established SV2A radiotracer produced at our Centre to determine the feasibility of integrating PET imaging in to psilocybin trials. The preliminary imaging data will assess whether psilocybin's antidepressant effects are related to changes in synaptic density in adults with TRD, and whether any changes in synaptic density are associated with psilocybin's actions on the 5-HT2AR.

Who is the study for?
This trial is for adults with treatment-resistant depression, meaning standard treatments haven't worked for them. Participants should be in good physical health and not currently using psychoactive or hormonal medications.
What is being tested?
The study tests if psilocybin (from 'magic mushrooms') affects synaptic density in the brain differently when taken alone versus with risperidone, a medication that blocks some of its effects. It involves PET imaging to track changes.
What are the potential side effects?
Psilocybin can cause psychedelic experiences, emotional swings, nausea, and headaches. Risperidone may lead to weight gain, fatigue, dry mouth, restlessness and could potentially dampen psilocybin's effects.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~24 months
This trial's timeline: 3 weeks for screening, Varies for treatment, and 24 months for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Feasibility of obtaining PET imaging scans before and after administration of psilocybin (25 mg) with and without risperidone (1 mg).
Secondary study objectives
Obtain preliminary data on synaptic density (as measured by [18F] SynVesT-1 volume distribution, VT) in brain regions relevant to MDD (i.e., hippocampus, prefrontal cortex)
Other study objectives
Change in the Montgomery-Åsberg Depression Rating Scale (MADRS) from Baseline to 1-week post-treatment.

Trial Design

2Treatment groups
Experimental Treatment
Group I: Risperidone (1 mg) + Psilocybin (25 mg)Experimental Treatment2 Interventions
o One capsule of risperidone 1 mg will be taken first followed 60 minutes later by one capsule of psilocybin 25 mg. Both capsules will be taken orally with a glass of water.
Group II: Psilocybin (25 mg)Experimental Treatment1 Intervention
One capsule of psilocybin 25 mg will be taken orally with a glass of water.

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Who is running the clinical trial?

Centre for Addiction and Mental HealthLead Sponsor
366 Previous Clinical Trials
82,331 Total Patients Enrolled
Muhammad Ishrat Husain, MBBS, MDPrincipal InvestigatorCentre for Addiction and Mental Health
1 Previous Clinical Trials
16 Total Patients Enrolled
~8 spots leftby Aug 2026
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