NCT06564818 · Cybin IRL Limited
"A Study of a Deuterated Psilocin Analog (CYB003) in Humans With Major Depressive Disorder"
(APPROACH)
What this study is about
The purpose of this study is to examine the effectiveness, safety, and tolerability of CYB003 compared to matching placebo as adjunctive treatment in participants with MDD.
View original scientific description
The purpose of this study is to examine the efficacy, safety, and tolerability of CYB003 compared to matching placebo as adjunctive treatment in participants with MDD.
Interventions
DRUG
CYB003
CYB003 is a Deuterated Psilocin Analog.
BEHAVIORAL
Psychological Support
Manualized psychological support performed by facilitators
DRUG
Placebo
Placebo
Primary outcome measures
Montgomery-Åsberg Depression Rating Scale (MADRS)
Time frame: Screening Day-45, Baseline Day-1, Day 2, Day 10, Day 21, Day 23, Day 31, and Day 42 (End of Treatment)
The MADRS is a 10-item scale with ratings based on a clinical interview which moves from broadly phrased questions about symptoms to more detailed ones allowing a precise rating of severity.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Participants must meet all the following criteria to be included in the trial:
- Aged 18 to 85 years inclusive, at Screening
- Participant has a diagnosis of MDD (single or recurrent episode as defined by DSM-5 TR \[if single episode, duration of ≥4 weeks and ≤24 months\] and established as per evaluation by the Investigator. The first MDD episode must have occurred prior to age 60.
- Depression is of moderate to severe degree at Screening, independently confirmed by additional clinical assessments
- Participant has been on a stable dose of a single antidepressant medication at an adequate dose (label specified) for an adequate duration in the last 4 weeks prior to Screening and has had an inadequate response (less than 50% improvement), as judged by the Investigator and clinical interviews.
- Participant has a body mass index (BMI) of 40 kg/m2 or less (BMI ≤ 40 kg/m2), inclusive, at Screening.
- Participant is able to refrain from nicotine use during the dosing s
Where
- Phoenix, Arizona
- Tucson, Arizona
- Bellflower, California
- La Jolla, California
- Los Angeles, California
- Montclair, California
- Oceanside, California
- San Francisco, California
- San Juan Capistrano, California
- Denver, Colorado
- Evergreen, Colorado
- Hollywood, Florida
And 27 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 2, 2026 · Source of record for eligibility and locations