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NCT03533556 · ClinicalTrials.gov registry record · Early Phase 1
Effects of L-theanine and Caffeine on Attention and Attention-related Brain Activity of Children With Attention Deficit Hyperactivity Disorder
A Early Phase 1 study of Attention Deficit Hyperactivity Disorder, sponsored by Texas Tech University.
- Completed
- Registry status
- Early Phase 1
- Development phase
- 6
- Enrollment target
- 1
- Study location
NCT03533556: Completed Early Phase 1 study of Attention Deficit Hyperactivity Disorder, sponsored by Texas Tech University.
NCT03533556 is a Early Phase 1 study of Attention Deficit Hyperactivity Disorder that has completed, run by Texas Tech University. The registered enrollment target is 6 participants, below the 217-participant average among 102 other Attention Deficit Hyperactivity Disorder trials with a reported enrollment target (97% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03533556, a Early Phase 1 study of Attention Deficit Hyperactivity Disorder, has completed, sponsored by Texas Tech University.
- COMPLETED
- Registry status
- Early Phase 1
- Development phase
- 6 participants
- Enrollment target
- 1
- Study location
Study Summary
L-theanine and caffeine are two natural constituents of tea. Both of these compounds are among the U.S. Food and Drug Administration's list of Generally Recognized as Safe (GRAS) substances. Results of several clinical trials the PI and his team has conducted are consistent with results of many others to indicate that oral intake of each of 2.5 mg/kg body weight of L-theanine and 2.0 mg/kg body weight of caffeine is associated with improved attention in adults. Furthermore, there is evidence to suggest that, when taken in combination, L-theanine and caffeine seem to have additive effects in improving attention in adults. However, the specific actions of these substances have not been examined in children and adolescents with attention deficit hyperactivity disorder (ADHD), who are characterized by impaired attention, hyperkinesia and impulsivity. Therefore, the investigators plan to study the functional activity of brains (both at rest and when performing standard tasks designed to measure attention) in children diagnosed with ADHD using functional magnetic resonance imaging, after they consume either 2.5 mg/kg of L-theanine, 2.0 mg/kg of caffeine and their combination as compared to a placebo (water). Based on our previous findings, the investigators expect to observe improvements (speed of responding and accuracy) in standard tests of attention with intake of L-theanine, caffeine and their combination as compared to the placebo. The investigators also expect to observe decreased functional activity in brain regions that typically show increased activity during mind wandering with intake of L-theanine, caffeine and their combination.
Primary Outcome
L-theanine, caffeine, L-theanine-caffeine combination and placebo will be administered on 4 separate days (at least 5 days apart) in a random counter-balanced order. Differences of functional magnetic resonance imaging reactivity of the whole brain, anterior and posterior nodes of the default mode network, bilateral dorsolateral prefrontal cortex and anterior cingulate cortex in response to stop signals of a stop signal reaction time task following administration of each treatment will be compar
Conditions Studied
Interventions
- OTHER Placebo
- DIETARY_SUPPLEMENT L-theanine
- DIETARY_SUPPLEMENT Caffeine
- DIETARY_SUPPLEMENT L-theanine-Caffeine Combination
Study Locations (1)
Texas
- Texas Tech University - Department of Human Development and Family Studies - Lubbock
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 6 participants |
| Start Date | 2018-05-14 |
| Est. Completion | 2018-08-31 |
| Phase | Early Phase 1 |
What the finished NCT03533556 record still lists
NCT03533556 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 6 participants, a relatively small participant target, below the 217-participant average among 102 other Attention Deficit Hyperactivity Disorder trials with a reported enrollment target (97% lower).
The record links to 1 condition, with Attention Deficit Hyperactivity Disorder appearing as the primary indexed condition, and to 4 interventions - of which Placebo is the first listed.
NCT03533556 reports a single indexed study location in Texas.
Frequently Asked Questions
What is clinical trial NCT03533556 about?
NCT03533556 is a clinical study titled "Effects of L-theanine and Caffeine on Attention and Attention-related Brain Activity of Children With Attention Deficit Hyperactivity Disorder". L-theanine and caffeine are two natural constituents of tea. Both of these compounds are among the U.S. Food and Drug Administration's list of Generally Recognized as Safe (GRAS) substances. Results of several clinical trials the PI and his team has conducted are consistent with results of many othe...
What is the current status of trial NCT03533556?
This trial is currently completed. It is a Early Phase 1 study. The enrollment target is 6 participants. The study started on 2018-05-14. Estimated completion is 2018-08-31.
What conditions does trial NCT03533556 study?
This clinical trial studies the following conditions: Attention Deficit Hyperactivity Disorder.
What interventions are being tested in trial NCT03533556?
The interventions under investigation include: Placebo (OTHER), L-theanine (DIETARY_SUPPLEMENT), Caffeine (DIETARY_SUPPLEMENT), L-theanine-Caffeine Combination (DIETARY_SUPPLEMENT).
Who is sponsoring clinical trial NCT03533556?
This trial is sponsored by Texas Tech University, which has 69 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT03533556 being conducted?
This trial has 1 study location across Texas. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
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Where NCT03533556's enrollment target sits among peer trials
6 103rd of 102 the lowest of 102 other Attention Deficit Hyperactivity Disorder trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Attention Deficit Hyperactivity Disorder 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.
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