Psilocybin for Amblyopia - Targeting Critical Periods in Humans (PATCH)

Psilocybin for Amblyopia - Targeting Critical Periods in Humans (PATCH)

The purpose of this study is to evaluate whether ingestion of a drug called psilocybin can increase the effectiveness of amblyopia therapy in adults with amblyopia. Psilocybin is a naturally-occurring psychoactive compound found in many species of mushrooms. It can be ingested orally and can result in strong but short-term (4-6 hours) effects such as changes in perception, thoughts, and emotions.

Study Overview

• Status: Recruiting
• Conditions: Amblyopia
• Intervention / Treatment: Behavioral: Amblyopia Therapy; Drug: 1 mg Psilocybin; Drug: 5 mg Psilocybin; Drug: 10 mg Psilocybin; Drug: 15 mg Psilocybin; Drug: 20 mg Psilocybin; Drug: 25 mg Psilocybin

Detailed Description

Participation in this study involves up to 12 visits over 9-13 weeks, including a screening visit, a preparation visit, two all-day experimental drug administration sessions with psilocybin, and eight follow up visits.The purpose of these follow-up visits is to deliver in-lab amblyopia therapy, measure visual function, and monitor safety. Participants will also be asked to complete amblyopia therapy at home: this will involve wearing an eyepatch or an eyeglasses filter over the non-amblyopic eye every day for up to several hours and completing online training exercises.

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Brian Winston; Phone Number: 410-550-2253; Email: bwinsto2@jh.edu

Study Locations

• United States
  • Maryland
    • Baltimore, Maryland, United States, 21224
      • Recruiting
      • Johns Hopkins Center for Psychedelic and Consciousness Research
      • Principal Investigator: Frederick S. Barrett, PhD
      • Contact: Brian Winston; Phone Number: 410-550-2253; Email: bwinsto2@jh.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• 18 to 65 years old
• Have given written informed consent
• Have at least a high-school level of education or equivalent (e.g. GED) and be fluent in English
• Be healthy and psychologically stable as determined by screening for medical and psychiatric problems via a personal interview, a medical questionnaire, medical history and physical examination, an electrocardiogram (ECG), and routine medical blood and urinalysis laboratory tests
• Women who are of child-bearing potential and sexually active agree to use highly effective means of birth control (i.e. implants, injectables, combined oral contraceptives, progestin-containing intrauterine device (IUD) or vasectomized partner) for the duration of this study
• Agree to consume approximately the same amount of caffeine-containing beverage (e.g. coffee, tea) that he/she consumes on a usual morning, before arriving at the research unit on the morning of the drug session day. If the participant does not routinely consume caffeinated beverages, he/she must agree not to do so on the session day.
• Agree to refrain from using any psychoactive drugs, including alcoholic beverages and nicotine, within 24 hours of each drug administration. The exception is caffeine.
• Agree not to take any as needed (PRN) medications on the mornings of drug sessions
• Agree not to take sildenafil (Viagra®), tadalafil, or similar medications within 72 hours of each drug administration.
• Agree that for one week before each drug session, he/she will refrain from taking any nonprescription medication, nutritional supplement, or herbal supplement except when approved by the study investigators. Exceptions will be evaluated by the study investigators and will include acetaminophen, non-steroidal anti-inflammatory drugs, and common doses of vitamins and minerals.
• Have a clinical diagnosis of amblyopia, with best-corrected visual acuity in the range of 0.2 - 1.0 LogMAR (approximately equivalent to 20/30 to 20/200)
• Has undergone an eye exam and prescription assessment within a recent period
• Has been wearing current spectacle correction for a minimum of six weeks prior to enrollment

Exclusion Criteria:

• Women who are pregnant (as indicated by a positive urine pregnancy test assessed at intake and before each drug session) or nursing; women who are of child-bearing potential and sexually active who are not practicing highly effective means of birth control (i.e. those that result in <1% failure rate per year; note that condoms alone are not considered highly effective)
• Cardiovascular conditions: coronary artery disease, stroke, angina, uncontrolled hypertension, a clinically significant ECG abnormality (e.g. atrial fibrillation), artificial heart valve, or transient ischemic attack (TIA) in the past year
• Epilepsy with history of seizures
• Insulin-dependent diabetes; if taking oral hypoglycemic agent, then no history of hypoglycemia
• Currently taking on a regular (e.g. daily) basis any medications having a primary centrally-acting serotonergic effect, including monoamine oxidase inhibitor (MAOIs). For individuals who have intermittent or PRN use of such medications, psilocybin sessions will not be conducted until at least five half-lives of the agent have elapsed after the last dose.
• Current or past history of meeting DSM-5 criteria for schizophrenia spectrum or other psychotic disorders (except substance/medication-induced or due to another medical condition)
• Current or past history within the last five years of meeting DSM-5 criteria for a severe alcohol or drug use disorder (excluding caffeine and nicotine)
• Have a first-degree relative with bipolar I disorder, schizophrenia spectrum, or other psychotic disorders (except substance/medication-induced or due to another medical condition)
• Has a psychiatric condition judged to be incompatible with establishment of rapport or safe exposure to psilocybin
• Explanation for visual acuity loss other than amblyopia, including cataracts, corneal disease, optic neuropathy, retinopathy, glaucoma, history of eye trauma or intraocular surgery, or any other ocular pathology as determined by study ophthalmologist

Study Plan

How is the study designed?

Design Details

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

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 1 mg Psilocybin with Amblyopia Therapy	Behavioral: Amblyopia Therapy; May include: eye-patching, Bangerter filtering, dichoptic training, perceptual learning; Drug: 1 mg Psilocybin; The psilocybin used in this study is synthetically manufactured and formulated under current good manufacturing practices (cGMP). The active drug is encapsulated using a size 0 blue gelatin capsule and contains 1 mg of psilocybin.
Experimental: 5 mg Psilocybin with Amblyopia Therapy	Behavioral: Amblyopia Therapy; May include: eye-patching, Bangerter filtering, dichoptic training, perceptual learning; Drug: 5 mg Psilocybin; The psilocybin used in this study is synthetically manufactured and formulated under current good manufacturing practices (cGMP). The active drug is encapsulated using a size 0 blue gelatin capsule and contains 5 mg of psilocybin.
Experimental: 10 mg Psilocybin with Amblyopia Therapy	Behavioral: Amblyopia Therapy; May include: eye-patching, Bangerter filtering, dichoptic training, perceptual learning; Drug: 10 mg Psilocybin; The psilocybin used in this study is synthetically manufactured and formulated under current good manufacturing practices (cGMP). The active drug is encapsulated using a size 0 blue gelatin capsule and contains 10 mg of psilocybin.
Experimental: 15 mg Psilocybin with Amblyopia Therapy	Behavioral: Amblyopia Therapy; May include: eye-patching, Bangerter filtering, dichoptic training, perceptual learning; Drug: 15 mg Psilocybin; The psilocybin used in this study is synthetically manufactured and formulated under current good manufacturing practices (cGMP). The active drug is encapsulated using a size 0 blue gelatin capsule and contains 15 mg of psilocybin.
Experimental: 20 mg Psilocybin with Amblyopia Therapy	Behavioral: Amblyopia Therapy; May include: eye-patching, Bangerter filtering, dichoptic training, perceptual learning; Drug: 20 mg Psilocybin; The psilocybin used in this study is synthetically manufactured and formulated under current good manufacturing practices (cGMP). The active drug is encapsulated using a size 0 blue gelatin capsule and contains 20 mg of psilocybin.
Experimental: 25 mg Psilocybin with Amblyopia Therapy	Behavioral: Amblyopia Therapy; May include: eye-patching, Bangerter filtering, dichoptic training, perceptual learning; Drug: 25 mg Psilocybin; The psilocybin used in this study is synthetically manufactured and formulated under current good manufacturing practices (cGMP). The active drug is encapsulated using a size 0 blue gelatin capsule and contains 25 mg of psilocybin.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Amblyopic Eye Visual Acuity	Measured using LogMAR scale	from Baseline to two weeks after experimental drug session 2
Change in Fellow Eye Visual Acuity	Measured using LogMAR scale	from Baseline to two weeks after experimental drug session 2

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Challenging Experiences Questionnaire (CEQ)	The Challenging Experience Questionnaire (CEQ) is a self-report measure designed to assess the intensity and quality of difficult or distressing experiences during psychedelic states. Score range 0-5, 0 is equivalent to no challenging experiences and 5 is an extreme (more than ever before in my life). Higher score "more difficult."	Approximately 7 hours after capsule administration during each experimental drug administration session (Visits 3 and 7; two weeks apart).
11-Dimensional Altered States of Consciousness Questionnaire (11D-ASC)	The 11D-ASC is a self-report questionnaire designed to assess the phenomenology of altered states of consciousness induced by psychedelics and other methods. The 11 dimensions are: 1) Experience of Unity, (2) Spiritual Experience, (3) Blissful State, (4) Insightfulness, (5) Disembodiment, (6) Impaired Control and Cognition, (7) Anxiety, (8) Complex Imagery, (9) Elementary Imagery, (10) Audio-Visual Synesthesia, and (11) Changed Meaning of Percepts. Each item is rated on a visual analog scale from 0 to 100, and scores for each dimension are calculated as the mean of the corresponding items, ranging from 0 to 100. Higher scores indicate greater intensity of the respective subjective experience, rather than a uniformly better or worse outcome.	Approximately 7 hours after capsule administration during each experimental drug administration session (Visits 3 and 7; two weeks apart).
The World Health Organization-Five Well-Being Index (WHO-5)	The WHO-5 is a five-item self-report measure of mental well-being over the preceding two weeks. Each item is scored from 0 to 5, yielding a raw total score ranging from 0 to 25. The raw score can be multiplied by four to obtain a percentage score ranging from 0 to 100. Higher scores indicate better mental well-being.	At the preparation session, one and two weeks after the first experimental drug administration session, and one, two, and eight weeks after the second drug administration session.
Amblyopia and Strabismus Questionnaire: English (ASQE)	The ASQE is a 26-item self-report questionnaire assessing vision-related quality of life in adults with amblyopia and strabismus. Item responses are converted to scores ranging from 0 to 100, and the total score is calculated as the mean of the item scores, ranging from 0 to 100. Higher scores indicate better vision-related quality of life, with 0 representing the worst and 100 the best possible outcome.	At the preparation session, two weeks after the first experimental drug administration session, and two and eight weeks after the second experimental drug administration session
Sheehan Disability Scale (SDS)	The Sheehan Disability Scale (SDS) is a patient-rated questionnaire assessing functional impairment across three domains: work/school, social life, and family life/home responsibilities. Each domain is rated on an 11-point scale from 0 (no impairment) to 10 (extreme impairment). The three domain scores are summed to yield a total score ranging from 0 to 30. Higher scores indicate greater functional impairment (worse functioning), while lower scores indicate less impairment (better functioning).	At the preparation session, two weeks after the first drug administration session, and two and eight weeks after the second drug administration session.

Collaborators and Investigators

• Sponsor: Johns Hopkins University
• Investigators: Principal Investigator: Frederick Barrett, MD, Johns Hopkins University

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): July 1, 2028
• Study Completion (Estimated): September 1, 2028

Study Registration Dates

• First Submitted: October 30, 2026
• First Submitted That Met QC Criteria: October 30, 2026
• First Posted (Actual): November 5, 2026

Study Record Updates

• Last Update Posted (Actual): November 5, 2026
• Last Update Submitted That Met QC Criteria: October 30, 2026
• Last Verified: October 1, 2026

More Information

Terms related to this study

• Keywords: psilocybin; amblyopia; psychedelic; lazy eye; anisometropia; refractive amblyopia; anisometropic amblyopia
• Additional Relevant MeSH Terms: Neurologic Manifestations; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Eye Diseases; Refractive Errors; Vision Disorders; Sensation Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Amblyopia; Anisometropia; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Alkaloids; Indoles; Indole Alkaloids; Indolizidines; Indolizines; Tryptamines; Psilocybin
• Other Study ID Numbers: IRB00519391

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