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NCT03336398 · ClinicalTrials.gov registry record · Phase 2
Investigation of the NMDA Antagonist Ketamine as a Treatment for Tinnitus
A Phase 2 study, sponsored by New York State Psychiatric Institute.
- Completed
- Registry status
- Phase 2
- Development phase
- 42
- Enrollment target
NCT03336398: Completed Phase 2 study, sponsored by New York State Psychiatric Institute.
NCT03336398 is a Phase 2 study that has completed, run by New York State Psychiatric Institute. The registered enrollment target is 42 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (68% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03336398, a Phase 2 study, has completed, sponsored by New York State Psychiatric Institute.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 42 participants
- Enrollment target
Study Summary
Tinnitus, or ringing in the ears, is a very common problem that often accompanies hearing loss. It affects up to 1 in 10 adults, and about 30% of people who experience chronic tinnitus find it very distressing. In these patients, symptoms of depression and anxiety often accompany tinnitus and there are no approved treatments. Clinical trials are ongoing to test a glutamate NMDA receptor antagonist (called esketamine), which is injected into the inner ear. However, the preliminary results with this medication show that it only works for tinnitus that results from acute injury. It does not treat tinnitus resulting from progressive hearing loss. Research in humans and animals suggest that the neurotransmitters glutamate and GABA are important in the development and maintenance of tinnitus. This data shows that over-activation of the NMDA receptor and a decrease in GABA signaling in the brain play a crucial role. Previous studies show that ketamine, which an antagonist at the NMDA receptor, increases GABA levels in the brain in participants with depression. Thus, in this experiment, this study will test the effect of ketamine on tinnitus, since it blocks the NMDA glutamate receptor and increase GABA levels. Two groups of participants will be included in this study: those who experience distress (symptoms of anxiety or depression) with tinnitus and those who have tinnitus but do not experience distress. Each participant will receive both ketamine and placebo on different days. Magnetic Resonance Spectroscopy (MRS) scans will be
Primary Outcome
The GABA and Glutamate/Glutamine (Glx) peaks will be quantified as ratios (relative to water) and are obtained from the auditory cortex using 3T Magnetic Resonance Spectroscopy (MRS). Brain spectra containing GABA and Glutamate/Glutamine (Glx) resonances will be acquired of the auditory cortex using the volume-selective PRESS J-editing difference method. Data will be acquired from a voxel centered on Heschl's sulcus. The GABA and Glx peak areas will be quantified as ratios relative to the area o
Interventions
- DRUG Ketamine Hydrochloride in saline
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 42 participants |
| Start Date | 2019-09-01 |
| Est. Completion | 2024-07-01 |
| Phase | Phase 2 |
What the finished NCT03336398 record still lists
NCT03336398 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 42 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (68% lower).
The record links to 0 conditions, and to 1 intervention - of which Ketamine Hydrochloride in saline is the first listed.
NCT03336398 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03336398 about?
NCT03336398 is a clinical study titled "Investigation of the NMDA Antagonist Ketamine as a Treatment for Tinnitus". Tinnitus, or ringing in the ears, is a very common problem that often accompanies hearing loss. It affects up to 1 in 10 adults, and about 30% of people who experience chronic tinnitus find it very distressing. In these patients, symptoms of depression and anxiety often accompany tinnitus and there ...
What is the current status of trial NCT03336398?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 42 participants. The study started on 2019-09-01. Estimated completion is 2024-07-01.
What interventions are being tested in trial NCT03336398?
The interventions under investigation include: Ketamine Hydrochloride in saline (DRUG).
Who is sponsoring clinical trial NCT03336398?
This trial is sponsored by New York State Psychiatric Institute, which has 364 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03336398's enrollment target sits among peer trials
42 1339th of 2000 higher than 649 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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