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Recruiting Phase 2 NCT06668571

NCT06668571 Intravenous Ketamine for Treatment-Resistant Depression

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Clinical Trial Summary
NCT ID NCT06668571
Status Recruiting
Phase Phase 2
Sponsor Mayo Clinic
Condition Depressive Disorder, Treatment-Resistant
Study Type INTERVENTIONAL
Enrollment 30 participants
Start Date 2025-02-10
Primary Completion 2027-12-31

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age 65 Years
Study Type INTERVENTIONAL
Interventions
KetamineNormal Saline

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.

In Phase 2, researchers evaluate early signs of effectiveness. You may be randomized to receive the active treatment or a comparator. Monitoring continues closely.

This trial targets 30 participants in total. It began in 2025-02-10 with a primary completion date of 2027-12-31.

⚠ 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

The purpose of this study is to to evaluate the relationships between peak (% change from baseline) central GABA and Glu levels during a 40-min IV ketamine or normal saline infusion utilizing fMRS, and change in peripheral GABA and Glu levels from baseline to 24-hr postinfusion utilizing LCMS, with baseline to 24-hr post-infusion change in depression (MADRS) in 30 TRD adults.

Eligibility Criteria

Inclusion Criteria: * Ability to provide informed consent * Meets diagnostic criteria for major depressive disorder without psychotic features per the SCID DSM-IV-TR * PHQ-9 total score ≥ 15 at screening * Treatment-resistant depression, as defined by failure of at least two previous antidepressant treatments within the current depressive episode. Failed antidepressant treatments can include pharmacotherapy for depression at an adequate dose for at least 8 weeks, trial of transcranial magnetic stimulation (TMS) or an acute series of at least 6 administrations of electroconvulsive therapy (ECT) * Ability to pass a comprehension assessment test related to effects of ketamine and trial objectives and criteria Exclusion Criteria: * Inability to speak English * Inability to provide consent or have a legal guardian * Patients with a BMI \> 40 kg/m2. * Personality disorder being the primary diagnosis * Diagnosis of schizophrenia, schizoaffective disorder, bipolar disorder, or active psychotic symptoms * Active post-traumatic stress disorder symptoms based on clinical assessment * Ongoing prescription of \> 2 mg lorazepam equivalents (total) daily, or morning dosing of any benzodiazepine at the time of assessment * Medications known to affect glutamate (i.e., Riluzole, Carbamazepine) or GABA (zaleplon, zolpidem, zopiclone, Valproate, Gabapentin, Pregabalin, tiagabine, and vigabatrin) are prohibited within two weeks prior to administration of study drug and at least 24 hours after last dose of study drug * Monoamine Oxidase Inhibitors (MAOIs) are prohibited two weeks prior to administration of study drug * Opioid antagonists (naltrexone, naloxone, nalmefene, methylnaltrexone, buprenorphine and naloxone combination) are prohibited within two weeks prior to administration of study drug and at least 24 hours after last dose of study drug * CYP3A4 inducers carbamazepine and modafinil are prohibited within two weeks prior to administration of study drug and at least 24 hours after last dose of study drug. * Currently undergoing TMS, vagal nerve stimulation, or deep brain stimulation as either an acute or maintenance treatment of depression * ECT in the past 6 months * Any active or unstable medical condition judged by the study psychiatrist as conferring too great a level of medical risk to allow inclusion in the study * A history of bleeding in the brain * Arteriovenous malformation or a history of aneurysm * Use of methamphetamine, cocaine, or cannabis. Abuse of stimulant (s) within the prior 12 months * Any current substance use disorder (excluding nicotine and caffeine). Note: Persons will be allowed to enroll in this study if their substance use is in complete (not partial) and sustained (\> 1 year) remission * History of traumatic brain injury that resulted in loss of consciousness with brain bleeding * History of tonic-clonic (grand mal) seizures * Developmental delay, intellectual disability, or intellectual disorder * Clinical or self-reported diagnosis of delirium, encephalopathy, or related clinical diagnosis within the prior 12 months * Minor or Major Neurocognitive disorder * Received ketamine treatment for depression within the prior 2 months * History of either poor antidepressive response to or poor tolerability of ketamine (any route of administration) when previously administered * History of hypothyroidism unless taking a stable dose of thyroid medication and asymptomatic for 3 months * Hepatic insufficiency (2.5 X ULN for AST or ALT) within 3 months of consent, past liver transplant recipient, and/or clinical diagnosis of cirrhosis of the liver * Gastroesophageal reflux disease that is poorly managed * A diagnosis of Complex Regional Pain Syndrome (CRPS) * Pregnancy, or nursing * History of claustrophobia with active symptoms that would interfere with the MRI * Any contraindication to MRI safety questionnaire * Poorly controlled hypertension.

Contact & Investigator

Central Contact

Nicole Reinicke

✉ reinicke.nicole@mayo.edu

📞 507-422-1835

Principal Investigator

Balwinder Singh, M.D., M.S.

PRINCIPAL INVESTIGATOR

Mayo Clinic

Frequently Asked Questions

Who can join the NCT06668571 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, up to 65 Years, studying Depressive Disorder, Treatment-Resistant. 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 NCT06668571 trial and what does that mean for participants?

Phase 2 trials evaluate whether the treatment shows signs of effectiveness while continuing to monitor safety. More participants are enrolled than in Phase 1 to help refine the treatment protocol.

Is NCT06668571 currently recruiting?

Yes, NCT06668571 is actively recruiting participants. Contact the research team at reinicke.nicole@mayo.edu for enrollment information.

Where is the NCT06668571 trial being conducted?

This trial is being conducted at Rochester, United States.

Who is sponsoring the NCT06668571 clinical trial?

NCT06668571 is sponsored by Mayo Clinic. The principal investigator is Balwinder Singh, M.D., M.S. at Mayo Clinic. The trial plans to enroll 30 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: April 2026  ·  Data Methodology