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Recruiting Phase 1 NCT02994433

NCT02994433 NMDA Receptor Antagonist Nitrous Oxide Targets Affective Brain Circuits

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Clinical Trial Summary
NCT ID NCT02994433
Status Recruiting
Phase Phase 1
Sponsor Washington University School of Medicine
Condition Depressive Disorder, Major
Study Type INTERVENTIONAL
Enrollment 60 participants
Start Date 2017-01-27
Primary Completion 2027-04-30

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age 65 Years
Study Type INTERVENTIONAL
Interventions
Nitrous OxidePlacebo gasMRI

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 1 is the earliest stage of human testing — safety and dosage are the primary focus. Visits are frequent and medical supervision is intensive. You will be among the first people to receive this treatment.

This trial targets 60 participants in total. It began in 2017-01-27 with a primary completion date of 2027-04-30.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Most clinical major depression responds to standard treatments (medication and psychotherapy); however, a significant subset of depressed patients (15-20%) do not respond to these treatments and are referred to as treatment-resistant major depression (TRMD). New treatments for TRMD are needed, and one promising line of research are drugs known as N-methyl-D-aspartate (NMDA) glutamate receptor antagonists. In a recent pilot study, our group demonstrated that the NMDA antagonist nitrous oxide is effective in TRMD. This application proposes to take the next important step in understanding how nitrous oxide exerts its effects in the human brain by using state-of-the-art brain neuroimaging (functional connectivity magnetic resonance imaging) in a group of non-depressed, healthy volunteers and comparing the results to a group of TRMD patients. This study involves exposing approximately 25 non-depressed healthy participants and 25 TRMD participants to nitrous oxide and a placebo gas, to compare their brain images before and after each of the inhalation sessions. Sessions will be separated by at least one month to prevent treatment effects from carrying over into the following session. All willing and eligible subjects will undergo up to six functional connectivity MRI scans, and two inhalation sessions. Functional imaging in the brain will allow us to trace the interconnections between various parts of the brain, including those involved with emotion and depression. Other procedures will involve screening materials to ensure safety of the participants before beginning the study (i.e. no MRI scan contraindications) and that subjects meet eligibility criteria to being in the targeted age range, depression/non-depressed state, neurological disorder history, and no medication exclusions.

Eligibility Criteria

Inclusion Criteria: * Adults 18-65 years of age * Right-handed * Controls: Not meet The Fourth Edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for major depressive disorder (MDD) by scoring ≤7 on the Hamilton Depression Rating Scale (HDRS), 17-item; Treatment-Resistant Major Depression (TRMD) patients: Must meet a ≥17 score on the HDRS. * Controls: Must not have any history of depression as determined by reported history and medical record review; TRMD: Documented (chart review) failure to respond to ≥3-4 adequate dose/duration antidepressant treatments; ≥1 in the current depressive episode. * Good command of the English language Exclusion Criteria: * Meets criteria for any DSM-IV Axis I diagnosis as documented in medical records and as determined by structured clinical interview (except MDD for the TRMD group) * Known primary neurological disorders or medical disorders including dementia, stroke, encephalopathy Parkinson's Disease, brain tumors, multiple sclerosis, seizure disorder, severe cardiac or pulmonary disease * Any central nervous system active medication as determined by study investigator * Any known disease affecting drug metabolism and excretion (e.g. renal or liver disease) as determined by study investigator * Left-handedness * Not eligible for MRI scans (e.g. history of claustrophobia/implanted metal as per MRI Screening Tool) * Current use of psychotropic medications, antidepressants, or prescription or non-prescription drugs/herbals intended to treat depression or anxiety (control group only) * Any recent (within past 12 months) history of substance dependence or abuse, determined by reported history or urine drug screen * Ability to become pregnant and not using effective contraception * Contraindication against the use of nitrous oxide: 1. Pneumothorax 2. Bowel obstruction 3. Middle ear occlusion 4. Elevated intracranial pressure 5. Chronic cobalamin and/or folate deficiency treated with folic acid or vitamin B12 6. Pregnant patients 7. Breastfeeding women * Inability to provide informed consent * Any other factor that in the investigators' judgment may affect patient safety or compliance (e.g. distance greater than 100 miles from clinic).

Contact & Investigator

Central Contact

Britt Gott, MS

✉ gottb@wustl.edu

📞 314-362-2463

Principal Investigator

Charles R Conway, MD

PRINCIPAL INVESTIGATOR

Washington University School of Medicine

Frequently Asked Questions

Who can join the NCT02994433 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, up to 65 Years, studying Depressive Disorder, Major. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT02994433 trial and what does that mean for participants?

Phase 1 trials are the first stage of human testing. The primary goal is to assess safety and determine appropriate dosage levels. Participants are closely monitored. These trials typically involve a small number of volunteers.

Is NCT02994433 currently recruiting?

Yes, NCT02994433 is actively recruiting participants. Contact the research team at gottb@wustl.edu for enrollment information.

Where is the NCT02994433 trial being conducted?

This trial is being conducted at St Louis, United States.

Who is sponsoring the NCT02994433 clinical trial?

NCT02994433 is sponsored by Washington University School of Medicine. The principal investigator is Charles R Conway, MD at Washington University School of Medicine. The trial plans to enroll 60 participants.

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