Trial · NCT04977674
Glutamate and Opioid Mechanisms of Antidepressant Response to Ketamine
NCT04977674, Early phase 1, Completed, King's College London
3 sourcestrials-2026-11-12-0.4.0
Cite this record
ConductScience Library. Glutamate and Opioid Mechanisms of Antidepressant Response to Ketamine. Trials, record NCT04977674. Release trials-2026-11-12-0.4.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT04977674
On this page
Trial
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
- Title
- Glutamate and Opioid Mechanisms of Antidepressant Response to Ketamine
- NCT number
- NCT04977674
- Status
- Completed
- Phases
- Early phase 1
- Enrollment
- 27 participants, actual
- Lead sponsor
- King's College London
- Conditions
- Depressive Disorder, Treatment-Resistant
- Interventions
- Naltrexone, Placebo, Ketamine
- First posted
- 2021-07-27
- Last updated
- 2023-03-02
Source ClinicalTrials.gov
Registered outcomes3
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description |
|---|---|---|---|
| Primary | Change in Glutamate | Changes will be in the same session comparing the ketamine infusion period to the pre-ketamine infusion baseline | Compare changes in glutamate and GLX (glutamate +glutamine), referenced to total creatine (tCr), during ketamine infusion as measured by functional magnetic resonance spectroscopy (1H-fMRS) for naltrexone versus placebo pre-treatment conditions. Hypothesis: There will be a significant increase in glutamate measures during ketamine administration compared to a resting baseline condition in a medial prefrontal cortex (mPFC) /anterior cingulate cortex (ACC) region. Pre-treatment with naltrexone will attenuate this increase. |
| Secondary | Change in Resting State Functional Connectivity | Changes will be in the same session comparing post-infusion (immediately after ketamine infusion) to the pre-ketamine infusion baseline | Compare changes in functional connectivity as measured by resting state-fMRI post-ketamine administration for naltrexone versus placebo pre-treatment conditions. Hypotheses: 1. Ketamine administration will lead to significant reductions in functional brain connectivity between the subgenual anterior cingulate cortex (sgACC), default mode network (DMN) regions of interest (mPFC and posterior cingulate cortex (PCC)), thalamus, insula and ventral tegmental area (VTA) compared to a resting baseline condition. Pre-treatment with naltrexone will attenuate these reductions. 2. Ketamine administration will lead to a significant increase in functional brain connectivity between the sgACC and dorsolateral prefrontal cortex (DLPFC) compared to a resting baseline condition. Pre-treatment with naltrexone will attenuate this increase. |
| Secondary | Change in Cerebral Blood Flow | Changes will be in the same session comparing data collected 30 minutes after the ketamine infusion commences to the pre-ketamine infusion baseline | Compare changes in cerebral blood flow during ketamine infusion as measured by arterial spin labelling (ASL) for naltrexone versus placebo pre-treatment conditions. Hypothesis: Ketamine administration will lead to a significant increase in CBF in sgACC, pregenual ACC (pgACC), dorsal ACC (dACC) and thalamus regions of interest compared to a resting baseline condition. Pre-treatment with naltrexone will attenuate these increases. |
Source ClinicalTrials.gov
Outcomes0
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
None in this release.
Results by group0
Each measurement the trial posted, group by group, in the words and numbers it posted.
None in this release.
Participant flow0
How many started, completed or left each group, period by period.
None in this release.
Adverse events0
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
None in this release.
Adverse event totals0
The totals the trial posted for each group.
None in this release.
Papers1
The papers the trial lists on ClinicalTrials.gov.
| PMID | Listed as |
|---|---|
| 40707608 | DERIVED |
Source PubMed
Grants0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
None in this release.
Trial comparisons0
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
None in this release.
Tests0
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
None in this release.
Source
- Release
- trials-2026-11-12-0.4.0
- Release manifest SHA-256
- 0f4a8d8c48aee2a7573ae0fa94ecbeab70c1adbe449bbc95c424bc7d3e97b9d4
- Registry capture
- 2026-11-12
- Results copy, AACT
- 2026-03-23
- NIH clinical studies file
- 2026-11-13
Source ClinicalTrials.gov
Sources 3
- ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
- ClinicalTrials.govNone stated
- NIH RePORTER's clinical studies and project filesPublic domain
Each source's terms
- ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
- ClinicalTrials.govnone stated
- NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)
ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
For software
Read this trial from software.
The record and each of its lists are JSON, twenty rows a page. No key.
GET https://conductscience.org/api/trials/v1/NCT04977674
GET https://conductscience.org/api/trials/v1/NCT04977674/registered