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NCT04013555 · ClinicalTrials.gov registry record · Phase 1
The Effects of Kynurenine Aminotransferase Inhibition in People With Schizophrenia
A Phase 1 study, sponsored by University of Maryland, Baltimore.
- Completed
- Registry status
- Phase 1
- Development phase
- 88
- Enrollment target
NCT04013555: Completed Phase 1 study, sponsored by University of Maryland, Baltimore.
NCT04013555 is a Phase 1 study that has completed, run by University of Maryland, Baltimore. The registered enrollment target is 88 participants, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (47% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04013555, a Phase 1 study, has completed, sponsored by University of Maryland, Baltimore.
- COMPLETED
- Registry status
- Phase 1
- Development phase
- 88 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). The overall goal of the study is to examine how the medication N-acetylcysteine (NAC), when added to tryptophan, affects various cognitive functions, such as verbal and visual memory. The investigators will also use magnetic resonance imaging (MRI) to examine how NAC affects brain activity and chemicals.
Primary Outcome
The investigators will use the kynurenine serum measures to examine whether NAC compared to placebo blocks the peripheral conversion of kynurenine to KYNA.
Interventions
- DRUG Placebo
- DRUG N-acetylcysteine (NAC)
- DRUG Tryptophan
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 88 participants |
| Start Date | 2020-01-20 |
| Est. Completion | 2024-08-14 |
| Phase | Phase 1 |
What the finished NCT04013555 record still lists
NCT04013555 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 88 participants, a relatively small participant target, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (47% higher).
The record links to 0 conditions, and to 3 interventions - of which Placebo is the first listed.
NCT04013555 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04013555 about?
NCT04013555 is a clinical study titled "The Effects of Kynurenine Aminotransferase Inhibition in People With Schizophrenia". 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 NCT04013555?
This trial is currently completed. It is a Phase 1 study. The enrollment target is 88 participants. The study started on 2020-01-20. Estimated completion is 2024-08-14.
What interventions are being tested in trial NCT04013555?
The interventions under investigation include: Placebo (DRUG), N-acetylcysteine (NAC) (DRUG), Tryptophan (DRUG).
Who is sponsoring clinical trial NCT04013555?
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 NCT04013555's enrollment target sits among peer trials
88 650th of 2000 higher than 1,350 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 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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