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NCT03283670 · ClinicalTrials.gov registry record · Phase 2
Inhaled Nitrous Oxide for Treatment-Resistant Depression: Optimizing Dosing Strategies
A Phase 2 study, sponsored by Washington University School of Medicine.
- Completed
- Registry status
- Phase 2
- Development phase
- 24
- Enrollment target
NCT03283670: Completed Phase 2 study, sponsored by Washington University School of Medicine.
NCT03283670 is a Phase 2 study that has completed, run by Washington University School of Medicine. The registered enrollment target is 24 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (82% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03283670, a Phase 2 study, has completed, sponsored by Washington University School of Medicine.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 24 participants
- Enrollment target
Study Summary
The purpose of the study aims to determine whether different concentrations of nitrous oxide (N2O) have different antidepressant effects for adults with treatment-resistant major depression.
Primary Outcome
Change in depression symptoms measured by the Hamilton Depression Rating Scale- 21 items. The HAMD-21 is designed to rate the severity of depression in patients. Although it contains 21 areas, calculate the patient's score as the total score on the first 17 answers. Scale: 0=absent, 4=worst level possible) the scores on the individual items are summed. Changes will be based on measurements obtained at baseline, approximately 2 hours after inhalation, and approximately 24 hours after inhalation.
Interventions
- DRUG Nitrous Oxide 25%
- DRUG Nitrous Oxide 50%
- DRUG Placebo Gas
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 24 participants |
| Start Date | 2016-11-22 |
| Est. Completion | 2020-02-18 |
| Phase | Phase 2 |
What the finished NCT03283670 record still lists
NCT03283670 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 24 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (82% lower).
The record links to 0 conditions, and to 3 interventions - of which Nitrous Oxide 25% is the first listed.
NCT03283670 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03283670 about?
NCT03283670 is a clinical study titled "Inhaled Nitrous Oxide for Treatment-Resistant Depression: Optimizing Dosing Strategies". The purpose of the study aims to determine whether different concentrations of nitrous oxide (N2O) have different antidepressant effects for adults with treatment-resistant major depression.
What is the current status of trial NCT03283670?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 24 participants. The study started on 2016-11-22. Estimated completion is 2020-02-18.
What interventions are being tested in trial NCT03283670?
The interventions under investigation include: Nitrous Oxide 25% (DRUG), Nitrous Oxide 50% (DRUG), Placebo Gas (DRUG).
Who is sponsoring clinical trial NCT03283670?
This trial is sponsored by Washington University School of Medicine, which has 1,502 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03283670's enrollment target sits among peer trials
24 1756th of 2000 higher than 217 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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