Does Psilocybin Change Synaptic Density in Amnestic Mild Cognitive Impairment
Launched by CENTRE FOR ADDICTION AND MENTAL HEALTH · Sep 14, 2023
Trial Information
Current as of June 28, 2025
Recruiting
Keywords
ClinConnect Summary
This clinical trial is studying how psilocybin, a naturally occurring compound found in certain mushrooms, affects brain connections in people with amnestic Mild Cognitive Impairment (aMCI). The researchers want to see if taking psilocybin can increase synaptic density, which refers to the number of connections between brain cells. They believe that if these connections improve, participants might also experience better thinking and memory skills. The trial will include 60 participants—30 with aMCI and 30 healthy volunteers—who will be randomly assigned to receive either psilocybin or a placebo (a non-active substance) over two weeks.
To be eligible, participants should be between 60 and 75 years old, speak English, and have certain cognitive testing scores that indicate memory issues for the aMCI group. The trial involves several PET scans to measure brain activity and cognitive assessments to track any changes in thinking abilities. Participants will be monitored before treatment and at multiple points after to evaluate the effects of psilocybin. It's important to note that individuals with certain medical or psychological conditions may not qualify for the study.
Gender
ALL
Eligibility criteria
- • Inclusion Criteria
- The aMCI participant must meet all of the inclusion criteria to be eligible for this clinical trial:
- • 1. Male or female participants of any race or ethnicity
- • 2. Inpatients or outpatients 60 to 75 years of age (on day of randomization)
- • 3. Diagnosis of MCI based on DSM 5 diagnostic criteria of Minor Neurocognitive Disorder
- • 4. Categorization of episodic memory impairment based on scores ≥ 1.0 SD lower on any of the following measures in comparison to normative data i. Logical Memory Test, ii. California Verbal Learning Test, iii. Brief Visual Memory Test
- • 5. Non-smoker/Non-nicotine user
- • 6. Montreal Cognitive Assessment (MoCA) score = \< 26 and MMSE score \> = 24
- • 7. Capable of consenting to participate in the research study
- • 8. On a stable dose of medication for at least 2 months \[see section 5.6\], and unlikely to undergo changes in dose during the study
- • 9. Availability of a study partner who has regular contact with the participant
- • 10. Ability to read and communicate in English (with corrected vision and hearing, if needed)
- The Healthy Control participant must meet all of the inclusion criteria to be eligible for this clinical trial:
- • 1. Male or female participants of any race or ethnicity
- • 2. 60 to 75 years of age (on day of randomization)
- • 3. Does not meet SCID-5 criteria for Mild Neurocognitive Disorder, Alzheimer's disease, or other major neurocognitive disorder
- • 4. Non-smoker/Non-nicotine user
- • 5. Capable of consenting to participate in the research study
- • 6. On a stable dose of medication for at least 2 months \[see section 5.6\], and unlikely to undergo changes in dose during the study
- • 7. Availability of a study partner who has regular contact with the participant
- • 8. Ability to read and communicate in English (with corrected vision and hearing, if needed)
- • Exclusion Criteria
- An individual who meets any of the following criteria will be excluded from participation in this clinical trial:
- • 1. Unwilling or incapable to consent to the study
- • 2. Unstable medical or any concomitant major medical or neurological illness, including presence of a relative or absolute contraindication to psilocybin, i.e. a drug allergy, recent stroke history, uncontrolled hypertension, low or labile blood pressure, recent myocardial infarction, cardiac arrhythmic, severe coronary artery disease, or moderate to severe renal or hepatic impairment.
- • 3. History of head trauma resulting in loss of consciousness \> 30 minutes that required medical attention.
- • 4. DSM-5 diagnosis, with active symptoms in the last three months, of major depression; lifetime diagnosis of bipolar disorder; intellectual disability; Alzheimer's Disease; or a psychotic disorder
- • 5. DSM-5 substance dependence (except caffeine) within 12 months of entering the study
- • 6. Anticonvulsant, antidepressant, antipsychotic, mood stabilizer, opioid, or benzodiazepine use
- • 7. Use of serotonergic psychedelic drugs within the past 10 years
- • 8. Positive urine drug screen at the screening visit
- • 9. Having taken a cognitive enhancer (acetylcholinesterase inhibitor or memantine) within the past 6 weeks
- • 10. Acute suicidal or homicidal ideation
- • 11. Receiving treatment with medications such as levetiracetam that blocks SV2a binding, and/or inability to discontinue the following medications before study drug dosing: inhibitors of uridine 5'-diphospho-glucuronosyltransferase (UGT)1A9 and (UGT)1A10, and ALDH inhibitors and alcohol dehydrogenase (ADH) inhibitors.
- • 12. Exceeding allowed annual radiation exposure levels (20 mSv), as outlined by our PET Centre guidelines
- • 13. Disorders of coagulation or taking anticoagulant medication
- • 14. Having completed multiple PET scans in the past, such that participation in this study would cause participant to exceed lifetime limit (8 PET scans)
- • 15. Metal implants or pacemaker precluding an MRI scan or other contraindications to MRI (e.g., claustrophobia)
- • 16. Female with childbearing potential\*, pregnancy (as confirmed by a negative pregnancy test) or breastfeeding
- • 17. Active gender affirming hormonal treatment
- • 18. Any first-degree relative with a diagnosis of schizophrenia-spectrum disorder; psychotic disorder (unless substance-induced or due to a medical condition); or bipolar I or II disorder as determined by the family medical history form and discussions with the participant.
- • 19. Allergies to hydroxypropyl methylcellulose \*A woman/female or person who is not of childbearing potential is considered to be postmenopausal after at least 12 months without menstruation. Postmenopausal is defined as 12 consecutive months with no menses without an alternative medical cause. Females/people of childbearing potential are those who have experienced menarche and do not meet the criteria for women not of childbearing potential.
About Centre For Addiction And Mental Health
The Centre for Addiction and Mental Health (CAMH) is Canada’s leading mental health and addiction teaching hospital, dedicated to advancing research, clinical care, and education in the field of mental health. With a commitment to improving the lives of individuals affected by mental illness and addiction, CAMH conducts innovative clinical trials aimed at developing and evaluating new treatment approaches. The institution fosters a collaborative environment that brings together researchers, clinicians, and community partners to translate scientific findings into effective interventions, ensuring the highest standards of care and support for patients. Through its robust research initiatives, CAMH strives to enhance understanding of mental health disorders and promote evidence-based practices in the treatment of addiction and mental health challenges.
Contacts
Jennifer Cobb
Immunology at National Institute of Allergy and Infectious Diseases (NIAID)
Locations
Toronto, Ontario, Canada
Patients applied
Trial Officials
Philip Gerretsen, MD, PhD
Principal Investigator
Centre for Addiction and Mental Health
Timeline
First submit
Trial launched
Trial updated
Estimated completion
Not reported