Who is eligible for clinical trial NCT03748446?

Participants must meet protocol criteria for Major Depressive Disorder. Confirm exact inclusion and exclusion requirements with the study coordinator.

Does clinical trial NCT03748446 provide travel or cost reimbursement?

Check with the site coordinator at the participating facility for travel and lodging stipend availability, and for which routine-care costs are covered.

🏛️ Verified NIH Record • Updated 2026-06-18

Xenon Inhalation Therapy for Major Depressive Disorder and Bipolar Disorder (NCT03748446)

🔵 Active, Not Recruiting Early Phase1 💊 Investigational Drug / Biologic Sponsor: Massachusetts General Hospital

🩺 Plain-English Summary (8th-Grade Level)

The investigators will test the hypothesis that inhaled xenon will produce a rapid improvement in depressive symptoms in patients suffering from treatment-resistant depression. Specifically, the investigators will conduct a parallel randomized, double-blind crossover study that will compare the effects of xenon-oxygen (35:65 ratio by volume) added to treatment as usual (X-TAU group) to the effects of nitrogen-oxygen (35:65 ratio by volume) added to treatment as usual (N-TAU group). A total of 20 severely depressed patients, 10 with major depressive disorder (MDD) and 10 with Bipolar Depression (BP), will be exposed in random order to N-TAU and X-TAU in a double-blind protocol.

Who can join: To join this study, participants generally need to meet the listed inclusion criteria (9 items) and avoid the listed exclusions (12 items).

Location: Dauten Family Center for Bipolar Treatment Innovation — Boston, Massachusetts

📋 "Do I Qualify?" — 1-Minute Self Screener

Instant Checklist

Check every box below. If you can check all of them, you may meet the study's basic screening requirements (final eligibility is confirmed by the site team).

Patient who meets DSM-V Criteria for MDD or Bipolar Depression (according to DSM-V), as the primary focus of treatment.
Able to understand the risks and benefits of participating in this clinical trial and give informed consent, per judgment of the investigator.
Age greater than or equal to 18 years but less than or equal to 65 years.
Montgomery Asberg Depression Rating Scale ≥20.
On an adequate antidepressant regimen (MDD) or on a mood stabilizing regimen (BP) that is stable for at least four weeks prior to enrollment.
Has reliable adult transportation from and to home.
Has a treating psychiatrist who is in agreement with the patient's participation in the study, and aware of the safety plan in the protocol.
No medical contraindications to receiving a xenon- or a nitrogen-oxygen mixture.
No serious or active pulmonary disease.

Usually NOT eligible if any of the following apply:

Exclusion Criteria:
MDD or BP disorder with psychosis, schizophrenia, OCD, or a primary anxiety disorder.
Currently taking a benzodiazepine (including PRN).
Unwilling or unable to comply with study procedures.
Active substance abuse in the past 60 days, diagnosis of substance dependence in the past 12 months, currently active smokers of any substance, including prescription marijuana.
Pregnant women or women of child bearing potential who are not using a medically accepted means of contraception.
Any unstable medical illness (cardiovascular, hepatic, renal, respiratory, endocrine, neurological, or hematological disease or uncontrolled seizure disorder).
Any history of brain injury and any active state involving entrapped air/gas within a body cavity with the potential to expand causing organ distension/compression (e.g., bowel obstruction, pneumothorax, or pneumocephalus).
History of hypersensitivity to xenon; history of multiple adverse drug reactions.
Have taken any investigational psychotropic drug within the last 6 months.
Inability to agree to comply with the visit schedule or study procedures.
Not appropriate for participation in a research trial per judgment of the investigator.

🔍 Extracted verbatim from the official NIH eligibility criteria. Always confirm with the study coordinator.

📍 All Participating Trial Locations (1 Sites)

Dauten Family Center for Bipolar Treatment Innovation — Boston, Massachusetts

💰 Cost, Insurance & Patient Rights

100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
Routine Patient Care: Under federal law (ACA § 2709) and many state statutes, routine care costs are covered during participation.
Voluntary Participation: You may withdraw at any time without affecting your standard medical care.

🏛️ View Official NIH Record ↗