Actively Recruiting
An Efficacy and Safety Study Comparing Two Doses of CYB003 and Placebo in Adults with Major Depressive Disorder
Led by Cybin IRL Limited · Updated on 2026-06-03
330
Participants Needed
67
Research Sites
7 weeks
Total Duration
On this page
Sponsors
C
Cybin IRL Limited
Lead Sponsor
W
Worldwide Clinical Trials
Collaborating Sponsor
AI-Summary
What this Trial Is About
Researchers are studying Major Depressive Disorder (MDD) to evaluate the effectiveness, safety, and tolerability of a drug called CYB003 compared to a placebo. This Phase III trial involves adults with moderate to severe depression who have not responded well to current antidepressant treatments. The study is sponsored by Cybin IRL Limited and aims to understand how well CYB003 works as an additional treatment alongside existing antidepressants. Participants will be divided into three groups. One group will receive 8 mg of CYB003 in two dosing sessions about three weeks apart, another group will receive 16 mg of CYB003 on the same schedule, and a third group will receive a placebo during the two sessions. All participants will continue their current antidepressant medication and receive psychological support throughout the study. Non-responders to placebo may be eligible for an extension trial to receive CYB003. During the trial, participants will be evaluated using several scales that measure depression severity, anxiety, global impression of illness, and quality of life at various points before, during, and after treatment. These assessments include the Montgomery-Asberg Depression Scale (MADRS), Beck Depression Inventory, and others. The study will monitor participants for safety and treatment effects over about 12 weeks, including follow-up visits at the end of the trial.
CONDITIONS
Brief Title
A Study of a Deuterated Psilocin Analog (CYB003) in Humans With Major Depressive Disorder
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Age 18 to 85 years
- Diagnosis of Major Depressive Disorder (single or recurrent episode) as defined by DSM-5 TR
- Moderate to severe depression confirmed at Screening and Baseline
- Stable dose of antidepressant medication for at least 4 weeks prior to Screening with inadequate response
- Body mass index (BMI) of 40 kg/m2 or less at Screening
- Ability to refrain from nicotine use during dosing sessions
- Use of effective contraception methods as required for participants and partners
- Postmenopausal or permanently sterile if non-childbearing potential
- Provided written informed consent including compliance with study requirements
You will not qualify if you...
- Current or past diagnosis of schizophrenia spectrum or other psychotic disorders
- History of bipolar disorder or borderline personality disorder
- Taking medication for ADHD
- Family history of schizophrenia, schizoaffective disorder, or bipolar disorder type 1 in first-degree relatives
- Significant suicide risk or recent suicidal behavior
- Treatment-resistant MDD defined by failure to respond to 2 or more antidepressants
- Recent electroconvulsive or brain stimulation therapies
- Current use of certain antidepressants, antipsychotics, or mood stabilizers
- Extensive lifetime or recent use of psychedelics
- Recent use of ketamine or S-ketamine
- Clinically relevant abnormal physical health or uncontrolled thyroid disorders
- Uncontrolled hypertension, arrhythmia, or abnormal heart rate
- Presence or history of organic brain disorders
- Recent use of certain supplements or blood/plasma donation
- Pregnancy, breastfeeding, planning to conceive, or unwillingness to abstain from egg/sperm donation as required
- History of serotonin syndrome
- Unwillingness to consent to audio and video recording of sessions
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - Approximately 6 weeks
Participants receive two dosing sessions of CYB003 or placebo approximately three weeks apart, while continuing their current antidepressants and receiving psychological support throughout the study.
2 dosing sessions approximately three weeks apart with additional psychological support visits
Duration - Up to 3 weeks after the last dosing session
Participants are monitored until the end of the trial for safety and efficacy assessments.
Multiple assessment visits up to Day 84/End of Trial
Trial Site Locations
Total: 67 locations
1
UAB Psychiatry and Behavioral Neurology
Birmingham, Alabama, United States, 35209
Actively Recruiting
2
Lighthouse Psychiatry
Gilbert, Arizona, United States, 85234
Actively Recruiting
3
Pillar Clinical Research - Little Rock
Little Rock, Arkansas, United States, 72204
Not Yet Recruiting
4
Behavioral Research Specialists, LLC
Glendale, California, United States, 91206
Actively Recruiting
5
Sun Valley Research Center
Imperial, California, United States, 92251
Not Yet Recruiting
6
CalNeuro Research Group
Los Angeles, California, United States, 90025
Actively Recruiting
7
ATP Clinical Research
Orange, California, United States, 92866
Actively Recruiting
8
NRC Research Institute
Orange, California, United States, 92868
Actively Recruiting
9
Inland Psychiatric Medical Group Inc (IPMG Research)
San Juan Capistrano, California, United States, 92675
Not Yet Recruiting
10
Psychedelic Science Institute
Santa Monica, California, United States, 90404
Actively Recruiting
11
Stanford University
Stanford, California, United States, 94305
Not Yet Recruiting
12
Yale School of Medicine - Yale Program for Psychedelic Science
New Haven, Connecticut, United States, 06511
Actively Recruiting
13
CNS Healthcare
Jacksonville, Florida, United States, 32256
Actively Recruiting
14
Accel Research Sites - Maitland
Maitland, Florida, United States, 32751
Actively Recruiting
15
Aqualane Clinical Research
Naples, Florida, United States, 34105
Actively Recruiting
16
Emory University Dept of Psychiatry and Behavioral Studies
Atlanta, Georgia, United States, 30329
Not Yet Recruiting
17
Psych Atlanta
Marietta, Georgia, United States, 30060
Actively Recruiting
18
Rush University
Chicago, Illinois, United States, 60612
Actively Recruiting
19
Tandem Clinical Research
Marrero, Louisiana, United States, 70006
Not Yet Recruiting
20
Johns Hopkins Medicine
Baltimore, Maryland, United States, 21224
Not Yet Recruiting
21
Institute for Integrative Therapies
Eden Prairie, Minnesota, United States, 55347
Actively Recruiting
22
Bio Behavioral Health
Toms River, New Jersey, United States, 08755
Actively Recruiting
23
New York State Psychiatric Institute
New York, New York, United States, 10032
Not Yet Recruiting
24
SP Research PLLC
Oklahoma City, Oklahoma, United States, 73112
Not Yet Recruiting
25
Adams Clinical Philadelphia
Philadelphia, Pennsylvania, United States, 19104
Actively Recruiting
26
Flourish Research Philadelphia
Philadelphia, Pennsylvania, United States, 19462
Actively Recruiting
27
Austin Clinical Trial Partners
Austin, Texas, United States, 78737
Not Yet Recruiting
28
North Texas Clinical Trials
Fort Worth, Texas, United States, 76104
Not Yet Recruiting
29
Brain Health Consultants and TMS Center
Houston, Texas, United States, 77046
Actively Recruiting
30
Flourish Research San Antonio
San Antonio, Texas, United States, 78229
Actively Recruiting
31
Core Clinical Research
Everett, Washington, United States, 98201
Not Yet Recruiting
32
Seattle Neuropsychiatric Treatment Center
Seattle, Washington, United States, 98104
Actively Recruiting
33
Royal Prince Alfred Hospital
Camperdown, New South Wales, Australia, 2050
Actively Recruiting
34
Thompson Brain & Mind Healthcare (TBMH)
Maroochydore, Queensland, Australia, 4558
Actively Recruiting
35
Ramsay Clinic
Melbourne, Victoria, Australia, 3004
Actively Recruiting
36
Neurocentrix Research
Melbourne, Victoria, Australia, 3053
Actively Recruiting
37
Monash University - Notting Hill
Notting Hill, Victoria, Australia, 3168
Actively Recruiting
38
Institute of neuropsychiatric Care (INEP)
Prague, Czechia
Not Yet Recruiting
39
Psyon s.r.o.
Prague, Czechia
Not Yet Recruiting
40
A-SHINE s.r.o.
Předměstí, Czechia
Not Yet Recruiting
41
Universitätsklinikum des Saarlandes und Medizinische Fakultät der Universität des Saarlandes
Homburg, Saarland, Germany, 66421
Not Yet Recruiting
42
Charité Universitaetsmedizin Berlin
Berlin, Germany, 10117
Not Yet Recruiting
43
University Hospital Frankfurt
Frankfurt am Main, Germany, 60528
Not Yet Recruiting
44
Central Institute of Mental Health
Mannheim, Germany, 68159
Not Yet Recruiting
45
Eginitio Hospital
Athens, Greece, 11528
Actively Recruiting
46
Attikon University Hospital
Athens, Greece, 12462
Actively Recruiting
47
Papageorgiou General Hospital
Thessaloniki, Greece, 56404
Actively Recruiting
48
Sheaf House - Tallaght Adult Mental Health Service
Dublin, Ireland, D24 WK80
Actively Recruiting
49
La Nua Day Hospital Mental Health Centre
Galway, Ireland, H91 VE03
Actively Recruiting
50
Uniwersytecki Szpital Kliniczny W Białymstoku
Bialystok, Poland, 15-272
Not Yet Recruiting
51
Promente - Centrum Neurologii i Psychogeriatrii w Bydgoszczy
Bydgoszcz, Poland, 85-133
Actively Recruiting
52
UCK
Gdansk, Poland, 80-214
Not Yet Recruiting
53
Centrum Badan Klinicznych PI-House Sp. z o.o
Gdansk, Poland, 80-546
Not Yet Recruiting
54
MTZ Clinical Research Powered by Pratia
Warsaw, Poland, 02-172
Not Yet Recruiting
55
Department of Pharmacology and Physiology of CNS
Warsaw, Poland, 02-957
Not Yet Recruiting
56
Cambridge University Hospital NHS
Cambridge, United Kingdom, CB1 2EU
Actively Recruiting
57
Clerkenwell Health - Doncaster
Doncaster, United Kingdom, DN4 8QN
Actively Recruiting
58
NHS Research Scotland
Edinburgh, United Kingdom, EH16 4TJ
Not Yet Recruiting
59
Queen Elizabeth University Hospital
Glasgow, United Kingdom, G51 4TF
Not Yet Recruiting
60
St Pancras Clinical Research
London, United Kingdom, EC2Y 8EA
Not Yet Recruiting
61
King's College London
London, United Kingdom, SE5 9RS
Actively Recruiting
62
Clerkenwell Health - Welbeck Street
London, United Kingdom, W1G 8DR
Actively Recruiting
63
Re:Cognition Health
London, United Kingdom, W1G9 RU
Actively Recruiting
64
Clerkenwell Health - Baker Street
London, United Kingdom, W1U 6RP
Actively Recruiting
65
Wolfson Unit - Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust
Newcastle upon Tyne, United Kingdom, NE4 6BE
Not Yet Recruiting
66
Ascend Clinical Research
Reading, United Kingdom, RG7 8PA
Actively Recruiting
67
Sheffield Health and Social Care NHS Foundation Trust
Sheffield, United Kingdom, S4 7QQ
Not Yet Recruiting
Research Team
C
Clinical Development
How is the study designed?
Study Type
INTERVENTIONAL
Masking
QUADRUPLE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
TREATMENT
Number of Arms
3
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