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NCT03866174 · ClinicalTrials.gov registry record · Phase 2
A Study of Psilocybin for Major Depressive Disorder (MDD)
A Phase 2 study, sponsored by Usona Institute.
- Completed
- Registry status
- Phase 2
- Development phase
- 347
- Enrollment target
NCT03866174: Completed Phase 2 study, sponsored by Usona Institute.
NCT03866174 is a Phase 2 study that has completed, run by Usona Institute. The registered enrollment target is 347 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (161% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03866174, a Phase 2 study, has completed, sponsored by Usona Institute.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 347 participants
- Enrollment target
Study Summary
One hundred participants, ages 21 to 65, who meet Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for major depressive disorder (MDD) will be stratified by study site and randomized with a 1-to-1 allocation under double-blind conditions to receive a single 25 mg oral dose of psilocybin or a single 100 mg oral dose of niacin. Niacin will serve as an active placebo. The purpose of this study is to evaluate the potential efficacy of a single 25 mg oral dose of psilocybin for MDD compared to the active placebo in otherwise medically-healthy participants, assessed as the difference between groups in changes in depressive symptoms from Baseline to Day 43 post-dose.
Primary Outcome
The MADRS is a clinician-rated scale designed to measure depression severity and to detect changes due to antidepressant treatment. The scale consists of 10 items, each of which is scored from 0 (item not present or normal) to 6 (severe or continuous presence of the symptoms), for a total score range of 0-60. Higher scores represent a more severe condition. The total (composite) MADRS score is used as the endpoint.
Interventions
- DRUG Niacin
- DRUG Psilocybin
- OTHER Set and Setting (SaS) Protocol
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 347 participants |
| Start Date | 2020-01-23 |
| Est. Completion | 2022-06-28 |
| Phase | Phase 2 |
What the finished NCT03866174 record still lists
NCT03866174 is an interventional study that assigns participants to a tested intervention. The registered 347 participants enrollment target is mid-sized for trials with a published cap, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (161% higher).
The record links to 0 conditions, and to 3 interventions - of which Niacin is the first listed.
NCT03866174 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03866174 about?
NCT03866174 is a clinical study titled "A Study of Psilocybin for Major Depressive Disorder (MDD)". One hundred participants, ages 21 to 65, who meet Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for major depressive disorder (MDD) will be stratified by study site and randomized with a 1-to-1 allocation under double-blind conditions to receive a single 25 mg oral dose of p...
What is the current status of trial NCT03866174?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 347 participants. The study started on 2020-01-23. Estimated completion is 2022-06-28.
What interventions are being tested in trial NCT03866174?
The interventions under investigation include: Niacin (DRUG), Psilocybin (DRUG), Set and Setting (SaS) Protocol (OTHER).
Who is sponsoring clinical trial NCT03866174?
This trial is sponsored by Usona Institute, which has 5 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03866174's enrollment target sits among peer trials
347 136th of 2000 higher than 1,865 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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