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PET Imaging of mGLuR5 With Drug Challenge

PET Imaging of mGluR5 With Drug Challenge

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01691092
Enrollment
79
Registered
2012-09-24
Start date
2012-06-30
Completion date
2016-02-29
Last updated
2017-04-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Major Depressive Disorder, Post-Traumatic Stress Disorder (PTSD)

Keywords

Depression, Ketamine, PET, PTSD

Brief summary

This study is designed to look at that involvement of a process in the brain called the glutamate system in depression. Participants will undergo a screening session, up to two functional Magnetic Resonance Imaging (fMRI) scans, and up to three Positron Emission Tomography (PET) scans, as well as cognitive testing at each scan session. For one of the PET scans, a drug (either ketamine or n-acetyl cysteine) will be administered. Hypothesis 1: The investigators hypothesize administration of ketamine or n-acetylcysteine (NAC) will lead to a decrease in mGluR5. Hypothesis 2: The investigators hypothesize an improvement in memory and attentional skills after drug challenge. Hypothesis 3: The investigators hypothesize an increase in mGluR5 availability and change in MRI measures post drug challenge as compared to baseline, signifying synaptogenesis. Hypothesis 4: We expect there should not be a significant difference in reduction in mGluR5 availability due to differences in ABP688 radiotracer infusion.

Detailed description

Aim 1: To determine the acute effect of medication-induced glutamate release on mGluR5 availability in human subjects. Hypothesis 1: We hypothesize administration of ketamine or n-acetylcysteine (NAC) will lead to a decrease in mGluR5 availability. Aim 2: To determine if glutamate release via administration of ketamine or NAC has pro cognitive benefits. Hypothesis 2: We hypothesize an improvement in memory and attentional skills after drug challenge. Aim 3: To determine if there is synaptogenesis detectable by PET and MRI post ketamine or NAC within a week of drug challenge (at the time of greatest antidepressant response). Hypothesis 3: We hypothesize an increase in mGluR5 availability and change in MRI measures, post drug challenge as compared to baseline, signifying synaptogenesis. Aim 4: To determine if there is a difference in reduction of mGluR5 availability after ketamine administration when radiotracer is administered bolus as compared to bolus to constant infusion in the same subjects (ABP688 radiotracer only). Hypothesis 4: We expect there should not be a significant difference in reduction in mGluR5 availability due to differences in ABP688 radiotracer infusion.

Interventions

DRUGKetamine

All subjects will receive ketamine to induce glutamate release in the brain

Sponsors

Yale University
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

* 18-65 years old * English speaking * No other Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) diagnosis present, besides required as below. Inclusion criteria for depressed subjects * clinical diagnosis of a current or past depressive episode * medication free for at least 2 weeks * Score \>16 on Hamilton Depression Rating Scale (HDRS) if currently depressed or \<11 if not currently depressed * treatment or non-treatment seeking who understand that this study is for research purposes only Inclusion criteria for healthy controls * no current, or history of, any DSM-IV diagnosis * no first-degree relative with history of psychotic, mood, or anxiety disorder Inclusion criteria for PTSD subjects * current Post-Traumatic Stress Disorder, as determined by the Structured Clinical Interview for DSM-IV-Text Revision (TR) (SCID) patient research edition * Clinician Administered PTSD Scale for DSM-IV-TR (CAPS) score of 50 or higher Inclusion criteria for trauma control subjects -history of trauma (meeting the criterion A of PTSD but not a full diagnosis of PTSD)

Exclusion criteria

* Current or past significant medical, neurological, or metabolic disorder or loss of consciousness for 5 minutes or more * active, significant suicidal ideation * implanted metallic devices or any Magnetic Resonance (MR) contraindications * women who are pregnant or breastfeeding * met DSM-IV criteria for alcohol/illicit substance dependence in their life-time or met alcohol/illicit substance abuse within past year * history of prior radiation exposure for research purposes within the past year such that participation in this study would place them over FDA limits for annual radiation exposure. This guideline is an effective dose of 5 rem received per year * blood donation within eight weeks of the start of the study * radiation exposure at work that precludes study participation * blood pressure \>140/80

Design outcomes

Primary

MeasureTime frameDescription
Change in Glutamate Levels at Baseline and After Ketamine Administration as Confirmed by Positron Emission Tomography (PET) Imaging1st scan: 90 minute baseline scan; 2nd scan: 90 minutes, ketamine administration at start of scan; scan 3: 90 minute scan 24 hours post ketaminePET imaging obtained in healthy and Major Depressive Disorder (MDD) subjects. Glutamate levels determined by radiotracer uptake in PET images.

Countries

United States

Participant flow

Participants by arm

ArmCount
Ketamine
All subjects will receive ketamine Ketamine: All subjects will receive ketamine to induce glutamate release in the brain
42
Total42

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyLost to Follow-up10
Overall Studynon-compliance3
Overall StudyPhysician Decision4
Overall Studyscreen fail19
Overall Studyused for different study2
Overall StudyWithdrawal by Subject3

Baseline characteristics

CharacteristicKetamine
Age, Continuous34.07143 years
STANDARD_DEVIATION 12.12615
diagnosis
Comorbid MDD & PTSD
4 Participants
diagnosis
Healthy Control (HC)
20 Participants
diagnosis
Major Depressive Disorder (MDD)
14 Participants
diagnosis
Post-Traumatic Stress Disorder (PTSD)
4 Participants
Sex: Female, Male
Female
28 Participants
Sex: Female, Male
Male
14 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
0 / 38
serious
Total, serious adverse events
1 / 38

Outcome results

Primary

Change in Glutamate Levels at Baseline and After Ketamine Administration as Confirmed by Positron Emission Tomography (PET) Imaging

PET imaging obtained in healthy and Major Depressive Disorder (MDD) subjects. Glutamate levels determined by radiotracer uptake in PET images.

Time frame: 1st scan: 90 minute baseline scan; 2nd scan: 90 minutes, ketamine administration at start of scan; scan 3: 90 minute scan 24 hours post ketamine

Population: 13 healthy (6 males, 7 females) and 14 MDD non-smokers (4 males, 10 females) Mean age: 33.5 ± 13.2 yrs reasons for discrepancy (participant flow module): some data was not able to be analyzed due to elevated metabolites; some subject did not tolerate ketamine and had to be pulled out of scanner so we could not obtain data.

ArmMeasureGroupValue (MEAN)Dispersion
KetamineChange in Glutamate Levels at Baseline and After Ketamine Administration as Confirmed by Positron Emission Tomography (PET) ImagingHC % reduction from baseline immediately post ket19 percentage reductionStandard Deviation 22
KetamineChange in Glutamate Levels at Baseline and After Ketamine Administration as Confirmed by Positron Emission Tomography (PET) ImagingMDD % reduction from baseline immediately post ket14 percentage reductionStandard Deviation 9
KetamineChange in Glutamate Levels at Baseline and After Ketamine Administration as Confirmed by Positron Emission Tomography (PET) ImagingHC % reduction from baseline 24 hrs post ket31 percentage reductionStandard Deviation 30
KetamineChange in Glutamate Levels at Baseline and After Ketamine Administration as Confirmed by Positron Emission Tomography (PET) ImagingMDD % reduction from baseline 24 hrs post ket14 percentage reductionStandard Deviation 13

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026