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NCT03356483 · ClinicalTrials.gov registry record · Phase 1
Efficacy of Psilocybin in OCD: a Double-Blind, Placebo-Controlled Study.
A Phase 1 study, sponsored by Yale University.
- Completed
- Registry status
- Phase 1
- Development phase
- 31
- Enrollment target
NCT03356483: Completed Phase 1 study, sponsored by Yale University.
NCT03356483 is a Phase 1 study that has completed, run by Yale University. The registered enrollment target is 31 participants, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (48% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03356483, a Phase 1 study, has completed, sponsored by Yale University.
- COMPLETED
- Registry status
- Phase 1
- Development phase
- 31 participants
- Enrollment target
Study Summary
This study aims to investigate the effects of oral psilocybin on OCD symptomatology and provide the first evidence of the neural mechanism that may mediate psilocybin's purported therapeutic effects on OCD.
Primary Outcome
Assesses severity and types of OCD symptoms over the past seven days. Consists of two parts: 1- symptom checklist, 2- symptom severity scale. The most prominent obsessions and compulsions are identified by the checklist and then rated by the symptom severity scale. The symptom severity scale consists of 11 items (3 items are not included in the total score) and uses a 0 to 4 severity scale. Total Y-BOCS scores range from 0 to 40, with higher scores indicating greater severity of OCD symptoms.
Interventions
- DRUG Psilocybin (0.25mg/kg)
- DRUG Niacin (250mg)
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 31 participants |
| Start Date | 2018-11-13 |
| Est. Completion | 2024-07-25 |
| Phase | Phase 1 |
What the finished NCT03356483 record still lists
NCT03356483 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 31 participants, a relatively small participant target, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (48% lower).
The record links to 0 conditions, and to 2 interventions - of which Psilocybin (0.25mg/kg) is the first listed.
NCT03356483 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03356483 about?
NCT03356483 is a clinical study titled "Efficacy of Psilocybin in OCD: a Double-Blind, Placebo-Controlled Study.". This study aims to investigate the effects of oral psilocybin on OCD symptomatology and provide the first evidence of the neural mechanism that may mediate psilocybin's purported therapeutic effects on OCD.
What is the current status of trial NCT03356483?
This trial is currently completed. It is a Phase 1 study. The enrollment target is 31 participants. The study started on 2018-11-13. Estimated completion is 2024-07-25.
What interventions are being tested in trial NCT03356483?
The interventions under investigation include: Psilocybin (0.25mg/kg) (DRUG), Niacin (250mg) (DRUG).
Who is sponsoring clinical trial NCT03356483?
This trial is sponsored by Yale University, which has 1,492 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03356483's enrollment target sits among peer trials
31 1322nd of 2000 higher than 669 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 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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