Clinical trial Recruiting at 1 site Early Phase 1 Interventional Ages 25 to 65

Measuring glutamate changes after ketamine to explain its fast antidepressant effects

Official title: Establishing Glutamatergic Changes as the Mechanism of Action in the Rapid Antidepressant Effects of Ketamine

Run by University of Pennsylvania · NCT06788249 · Data updated 2026-11-12

This trial will see if ketamine produces measurable changes in brain glutamate in adults with treatment-resistant major depressive disorder using high-field GluCEST imaging.

Quick facts

PhaseEarly Phase 1
Study typeInterventional
Ages25 Years to 65 Years
SexAll
Enrollment10 (estimated)
SponsorUniversity of Pennsylvania
Academic / other
Locations1 site (Philadelphia, Pennsylvania)
StatusRecruiting
StartedApril 1, 2026
Main results expectedDecember 15, 2026
Study endsDecember 15, 2026
Registry record updatedOctober 7, 2026
Trial IDNCT06788249 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults aged 25 to 65 with current, treatment-resistant major depressive disorder (failure of at least two adequate antidepressant or mood‑stabilizing treatments), who speak English and meet medical and psychiatric eligibility criteria, are ideal candidates.

Probably not a fit

People with bipolar disorder, psychotic disorders, recent alcohol or drug abuse, current smokers, certain sleep disorders, or significant medical conditions are excluded and would not be eligible to participate or likely benefit from this protocol.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Participants with treatment-resistant major depressive disorder will be screened virtually and complete diagnostic interviews and a 7-day sleep diary before an in-person study visit. On the study day they will undergo baseline GluCEST imaging on a 7T MRI, receive a ketamine infusion, and have follow-up imaging and mood assessments to track rapid biochemical and clinical changes. The protocol excludes people with bipolar or psychotic disorders, recent substance abuse, current smoking, or significant medical conditions. This pilot early-phase study aims to link glutamatergic signal changes to ketamine's antidepressant effects to inform future treatment development.

Why it matters

Potential benefit: If successful, the findings could point to new targets for faster-acting antidepressants that produce more sustained relief by modulating glutamatergic synaptic strength.

How similar studies have gone: Ketamine's rapid antidepressant effects are well established in prior studies, but applying high-field GluCEST imaging to directly link those effects to glutamatergic synaptic changes in humans is novel and largely untested.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Age between 25 and 65 years;
2. Current depression as assessed on the SCID;
3. Treatment-resistant depression, as defined by failure of at least two previous antidepressant or mood stabilizing treatments within the current depressive episode. Failed antidepressant or mood stabilizing treatments can include pharmacotherapy for depression at an adequate dose for at least 8 weeks
4. Able to comprehend English, as all questionnaires are in this language
5. Ability to provide informed consent Ability to pass a comprehension assessment test related to effects of ketamine and trial objectives and criteria.

Exclusion Criteria:

1. A sleep disorder other than insomnia, as determined by history;
2. History of bipolar disorder, delirium, dementia, amnestic disorder, schizophrenia and other psychotic disorders as assessed on the SCID;
3. Alcohol or drug abuse in the past year based upon the SCID or urine toxicology screen;
4. A current smoker;

4\) Any significant medical or neurological illness that impacts brain function or impedes participation; 5) History of head trauma with significant loss of consciousness; 6) Metallic implants, pacemakers or tattoos, or other contraindications to MRI; Claustrophobic, or intolerant of the scanner environment; 7) For women, pregnancy will exclude participation. 8) Untreated hypertension

Based on ketamine's known difficulties with induction of perceptual/psychomimetic symptoms, exclusion criteria for this study are as follows:

1. Patients with a BMI over 40.
2. Ongoing prescription of 4 mg lorazepam equivalents (total) daily, or morning dosing of any benzodiazepine at the time of assessment;
3. Currently undergoing ECT, transcranial magnetic stimulation, vagal nerve stimulation, or deep brain stimulation as either an acute or maintenance treatment of depression;
4. Use of any MAOI is prohibited two weeks prior to administration of study drug; if patients are on an MAOI when enrolled, study drug will not be administered until two weeks off MAOI;
5. CYP3A4 inducers carbamazepine and modafinil are prohibited two weeks prior to administration of study drug and at least 24 hours after last dose of study drug.
6. Current use of Naltrexone;
7. Developmental delay, mental retardation, or intellectual disorder;
8. Clinical or self-reported diagnosis of delirium, encephalopathy, or related clinical diagnosis within the prior 12 months;
9. Prior participation in another study of ketamine for depression
10. Prior treatment and/or recreational use of ketamine

Where it's running

  • University of Pennsylvania
    Philadelphia, Pennsylvania, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.