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Optimization of Blood Levels of 25(OH)-Vitamin D in African Americans
NCT04939792 · View on ClinicalTrials.gov ↗
Study Summary
Two-thirds of the US population, particularly African Americans (AA), is at risk for inadequate or deficient 25-hydroxy-vitamin D (25(OH)VD). Epidemiological studies demonstrate an association between better health outcomes and higher blood levels of 25(OH)VD . Randomized controlled clinical trials have shown that, while supraphysiological high doses of VD are needed to achieve adequate blood levels of 25(OH)VD, not all subjects respond to them. Recent studies have also questioned the therapeutic effects of high-dose VD supplementation. Severe VD deficiency has been associated independently with the future risk of mild cognitive impairment (MCI) and dementia. A reduction in GSH and an increase in the oxidative stress levels of serum, erythrocytes, and circulating lymphocytes has been observed in MCI and Alzheimer disease, findings similar to those in VD deficient persons. Scholarly reviews conclude that excess oxidative stress is one of the major risk factors for AD and support a potential therapeutic role for L-cysteine (LC, a GSH precursor) and vitamin D (VD) supplementation in the treatment of Alzheimer disease symptoms. This application presents the investigators' design for a randomized, double-blind, placebo-controlled clinical trial to test the hypothesis that supplementation with VD in combination with L-cysteine (LC) is more successful at optimizing the statuses of 25(OH)VD \[biological signatures\] and simultaneously decreasing TNF-α, IR \[functional or clinical outcomes\], and oxidative stress, suggesting a better therapeutic approach compared with supplementation with VD alone in AA subjects.
Conditions Studied
Interventions
- DRUG Placebo
- DRUG Vitamin D
- DRUG Vitamin D + L-cysteine
- DRUG L-cysteine
Study Locations (1)
Louisiana
- Louisiana State University Health Shreveport — Shreveport
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 165 participants |
| Start Date | 2020-11-06 |
| Est. Completion | 2022-10-31 |
| Phase | Early Phase 1 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT04939792
The ClinicalTrials.gov registry entry for NCT04939792 describes a study currently listed as completed. It is categorized as Early Phase 1, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 165 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Louisiana State University Health Sciences Center Shreveport, which has 9 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Vitamin D Deficiency appearing as the primary indexed condition, and to 4 interventions — of which Placebo is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT04939792 reports 1 study location spanning 1 distinct geographic area — top geographies include Louisiana. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT04939792 about?
NCT04939792 is a clinical study titled "Optimization of Blood Levels of 25(OH)-Vitamin D in African Americans". Two-thirds of the US population, particularly African Americans (AA), is at risk for inadequate or deficient 25-hydroxy-vitamin D (25(OH)VD). Epidemiological studies demonstrate an association between better health outcomes and higher blood levels of 25(OH)VD . Randomized controlled clinical trials ...
What is the current status of trial NCT04939792?
This trial is currently completed. It is a Early Phase 1 study. The enrollment target is 165 participants. The study started on 2020-11-06. Estimated completion is 2022-10-31.
What conditions does trial NCT04939792 study?
This clinical trial studies the following conditions: Vitamin D Deficiency. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT04939792?
The interventions under investigation include: Placebo (DRUG), Vitamin D (DRUG), Vitamin D + L-cysteine (DRUG), L-cysteine (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT04939792?
This trial is sponsored by Louisiana State University Health Sciences Center Shreveport, which has 9 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT04939792 being conducted?
This trial has 1 study location across Louisiana. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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