Sustained Mood Improvement With Laughing Gas Exposure (NCT07262008) | Clinical Trial Compass
Not Yet RecruitingPhase 3
Sustained Mood Improvement With Laughing Gas Exposure
Canada120 participantsStarted 2026-02-01
Plain-language summary
Multi-centre, parallel group, blinded, 1:1 randomized controlled trial to determine the effect of nitrous oxide on reducing symptoms of depression in patients with treatment resistant depression.
Who can participate
Age range
18 Years – 65 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. 18 to 65 years of age
. Meeting Diagnostic and Statistical Manual for Mental Disorders (DSM-5) criteria for Major Depressive Disorder (MDD)
. Current major depressive episode as confirmed by the Mini International Neuropsychiatric Interview (MINI) for DSM-5
. Experiencing moderate to severe depressive episodes, as defined by the Montgomery-Åsberg Depression Rating Scale (MADRS) \> 21
. Failure of two trials of antidepressant therapy of adequate dose and duration, during the current depressive episode
. For women of childbearing potential, use of highly effective or double-barrier methods of contraception. Abstinence is acceptable if it is the preferred and usual lifestyle of the female participant
. Capacity to provide informed consent.
Exclusion criteria
. Acute suicidality defined as score \> 4 on MADRS item 10
. Diagnosis of Bipolar Disorder
. Current substance abuse or dependence and/or history of alcohol abuse or dependence within the past year
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Change in Montgomery-Åsberg Depression Rating Scale (MADRS) score
Timeframe: Baseline to the 2-week follow-up (Visit 6 - Day 35).
. Current or lifetime history of schizophrenia or schizoaffective disorder
. Known history of hypersensitivity or allergy to nitrous oxide, midazolam or any ingredients in the study formulations
. Contraindication to receiving nitrous oxide (e.g. any condition where air is entrapped within a body and its expansion might be dangerous such as, pneumothorax, elevated intracranial pressure, air embolism, recent middle ear, vitreoretinal or bowel obstruction surgeries, etc.)
. Known chronic cobalamin or folate deficiency (e.g. signs of anemia or neurological symptoms, with plasma levels of homocysteine over 15 µmol/L and abnormal red blood cells and leukocytes on a complete blood count CBC) or current methotrexate use