Recruiting
Phase 2
Phase 3

Ketamine

Sponsor:

The Royal's Institute of Mental Health Research

Code:

NCT06891300

Conditions

Suicidal Ideation

Major Depressive Disorder (MDD)

Eligibility Criteria

Sex: All

Age: 18 - 65

Healthy Volunteers: Not accepted

Interventions

ketamine hydrochloride

Study Details

Brief summary:

The goal of this clinical trial is to treat active suicidal ideation in individuals with Major Depressive Disorder (MDD) using ketamine and to understand suicidal ideation by examining biological mechanisms using magnetic resonance imaging (MRI), and psychological mechanisms through validated clinical scales and qualitative interviews. The main questions it aims to answer are:

1. Will ketamine will reduce suicidal ideation in a significant proportion of study participants?
2. Will reduction in suicidal ideation will be accompanied by rapid changes in neuroimaging biomarkers?

Participants will receive four intravenous (IV) ketamine infusions administered twice weekly for two weeks. Participants will undergo two identical MRI scans: 1) within 48 hours prior to starting ketamine treatment, and 2) 24 hours after the fourth ketamine infusion. Suicidal ideation and depressive symptoms will be assessed prior to each imaging session alongside additional self-report measures. Qualitative interviews will occur within 72 hours after the fourth ketamine treatment.

Conditions

Suicidal Ideation

Major Depressive Disorder (MDD)

Study ID

NCT06891300

Start date

Apr 8, 2025

Status verified date

Apr, 2026

Completion date

Oct, 2026

Anticipated

Primary completion date

Oct, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 65

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. English speaking
2. Ages 18-65 years old
3. Suicidal ideation severity score ≥3 on the Columbia Suicide Severity Rating Scale (C-SSRS) (Baseline/Screening version) at Screening Visit ("active suicidal ideation with any methods")
4. Diagnosis of Major Depressive Disorder (MDD) according to the Diagnostic and Statistical Manual for Mental Disorders 5th Edition (DSM-5)
5. Willing to maintain stable doses of concomitant medications throughout the study
6. Be under the care of a designated health care provider (i.e., family physician or psychiatrist) to follow their care after the completion of the study.

Exclusion Criteria:

1. Participants not medically cleared to receive ketamine treatment due to presence of clinically relevant disease (e.g., uncontrolled hypertension, renal or hepatic impairment, significant coronary artery disease, diabetes mellitus, seizure disorder).
2. Known or suspected hypersensitivity or intolerance to ketamine
3. Body mass index (BMI) ≥35
4. History of a primary psychotic disorder (e.g., schizophrenia), or current or recent (<2 years) acute episode of psychosis
5. Current and/or recent history (<12 months) of substance use/dependence (except for caffeine or nicotine) or problematic current alcohol use or dependence as defined by DSM-5 criteria
6. Pregnant, breastfeeding or of childbearing potential and unwilling to use an approved method of contraception during the study
7. History of significant head injury including loss of consciousness >5 minutes
8. Any MRI contraindications
9. Concurrent use of ketamine in any form
10. Concurrent active ECT or repetitive transcranial magnetic stimulation (rTMS) therapy

Study Design

Enrollment

36 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Ketamine

Participants will undergo a total of four IV ketamine infusions (0.5 mg/kg infused over 40 minutes), administered twice weekly for two weeks.

Interventions

ketamine hydrochloride

Participants will undergo intravenous (IV) ketamine infusions (0.5 mg/kg infused over 40 minutes) under medical supervision. Treatments will be administered twice weekly for two weeks, for a total of four infusions.

Primary outcome measure

  • Change in white matter microstructure from pre-treatment to post-treatment, assessed via MRI. [ Time Frame: Pre-treatment (up to -48 hours) to post-treatment (24+/-6 hours) ]

Central Contacts and Locations

Central contacts

Locations

Royal Ottawa Mental Health Centre

Recruiting

Ottawa, Ontario, Canada, K1Z7K4

Contacts

Principal Investigator:

Jennifer Phillips, PhD

More Information

Sponsor

The Royal's Institute of Mental Health Research

Last update posted

May 19, 2026

Last verified

Apr, 2026

Keywords

  • Major Depressive Disorder
  • Suicidal Ideation
  • Ketamine
  • Neuroimaging

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by The Royal's Institute of Mental Health Research on 2026-05-19.