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NCT02067975 · ClinicalTrials.gov registry record · Phase 2
Tryptophan MRI in People With Schizophrenia and Healthy Controls
A Phase 2 study, sponsored by University of Maryland, Baltimore.
- Completed
- Registry status
- Phase 2
- Development phase
- 93
- Enrollment target
NCT02067975: Completed Phase 2 study, sponsored by University of Maryland, Baltimore.
NCT02067975 is a Phase 2 study that has completed, run by University of Maryland, Baltimore. The registered enrollment target is 93 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (30% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT02067975, a Phase 2 study, has completed, sponsored by University of Maryland, Baltimore.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 93 participants
- Enrollment target
Study Summary
Kynurenic acid (KYNA) is a naturally occurring chemical in the brain. Studies with rodents indicate that levels of KYNA can impact levels of the neurotransmitters glutamate and dopamine. One way to reliably increase KYNA levels is by ingesting the amino acid tryptophan. Tryptophan is a normal part of the human diet. Tryptophan gets metabolized/changed to other chemicals in the body- including KYNA. By giving people 6 grams of tryptophan, the investigators will be able to increase the KYNA level in a controlled way. The investigators will then be able to study the effects of KYNA on neurotransmitters by using cognitive tests and magnetic resonance imaging techniques (measuring brain activity and brain chemistry using the MRI magnet). They will test people using tryptophan and also using a placebo to look for differences. The investigators will test healthy controls and people with schizophrenia to look for differences.
Primary Outcome
The following assessment was used to assess the outcome measure: the Hopkins Verbal Learning Test-Revised (HVLT-R). HVLT total scores range from 0 to 36. In order to conduct group comparisons, the HVLT raw total scores are converted to a t-score (range: -10 to 80). The mean t-scores for each condition are below (see outcome measure data table). Higher scores represent better performance. Participants performed the same task before pre- and post-treatment with Tryptophan and again with placebo (2
Interventions
- DRUG Placebo
- DRUG Tryptophan
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 93 participants |
| Start Date | 2014-08-14 |
| Est. Completion | 2019-12-31 |
| Phase | Phase 2 |
What the finished NCT02067975 record still lists
NCT02067975 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 93 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (30% lower).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT02067975 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT02067975 about?
NCT02067975 is a clinical study titled "Tryptophan MRI in People With Schizophrenia and Healthy Controls". Kynurenic acid (KYNA) is a naturally occurring chemical in the brain. Studies with rodents indicate that levels of KYNA can impact levels of the neurotransmitters glutamate and dopamine. One way to reliably increase KYNA levels is by ingesting the amino acid tryptophan. Tryptophan is a normal part o...
What is the current status of trial NCT02067975?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 93 participants. The study started on 2014-08-14. Estimated completion is 2019-12-31.
What interventions are being tested in trial NCT02067975?
The interventions under investigation include: Placebo (DRUG), Tryptophan (DRUG).
Who is sponsoring clinical trial NCT02067975?
This trial is sponsored by University of Maryland, Baltimore, which has 560 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT02067975's enrollment target sits among peer trials
93 766th of 2000 higher than 1,234 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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