Nitrous Oxide in the Treatment of Acute Suicidal Ideation

Phase 2

Recruiting

• Conditions: Suicidality; EEG; Suicidal Ideation; Nitrous Oxide; Biomarkers / Blood; Biomarkers / Hair
• Interventions: Drug: 50% N2O plus 50% O2; Drug: Oxygen (O2)

• Registration Number: NCT06636357
• Lead Sponsor: University of Zurich

Brief Summary

The primary aim of the NITOS study is to investigate the potential rapid antisuicidal effects of N2O in the transdiagnostic treatment of suicidal ideation. On day 1, patients will receive either nitrous oxide (50% N2O balanced with oxygen) or placebo (50% oxygen balanced with air). Seven days after the first inhalation, a second inhalation will be performed. All patients will receive N2O at least once during this trial. While the first inhalation will be double-blind, only the patients but not the raters will be blinded to the second inhalation (day 8). For mechanism of action and prediction, a nested biomarker substudy will employ multimodal techniques including analysis of hair and blood samples, and EEG.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2024-09-06
• Status Verified: 2024-10
• Study First Submitted QC: 2024-10-09
• Study First Posted: 2024-10-10
• Study Start: 2025-01-13
• Last Update Submitted: 2025-01-13
• Last Update Posted: 2025-01-16
• Primary Completion: 2026-09-30
• Study Completion: 2026-09-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 85

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
50% nitrous oxide (N2O) plus 50% oxygen	50% N2O plus 50% O2	Patients will be treated with N20 (50% N2O combined with 50% oxygen) for 45 minutes. Both the study subject and the rater will be blinded to the treatment assignment.
50% oxygen plus 50% air	Oxygen (O2)	Here, patients will be treated with 50% oxygen plus air for 45 minutes. Both the study subject and the rater will be blinded to the treatment assignment.

Primary Outcome Measures

Name	Time	Method
Beck Scale for Suicidal Ideation (BSS)	Day 0 to Day 2	Change of BSS score between Day 0 and Day 2. Double-blind treatment with either N2O or placebo inhalation on Day 1.

Secondary Outcome Measures

Name	Time	Method
Montgomery-Åsberg Depression Rating Scale (MADRS )	Day 0 to Day 2
EEG changes associated with N2O / placebo inhalation	Day 1	EEG will be performed before, during, and after inhalation
Suicide Visual Analog Scale (S-VAS)	Day 1	Briefly, the S-VAS uses the phrase "urge to kill myself". Next to the phrase, the patient sees a line that is anchored on the left with the word "none" and on the right with the word "extreme" . Score ranges from 0 to 100.
Perceived Burdensomeness Visual Analog Scale (PB-VAS)	Day 1	The PB-VAS uses the phrase "like a burden". Next to the phrase, the patient sees a line that is anchored on the left with the word "none" and on the right with the word "extreme" . Score ranges from 0 to 100.

Trial Locations

Locations (1)

Psychiatric University Hospital Zurich; 🇨🇭 Zürich, Switzerland