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Completed Early Phase 1 Interventional Accepts healthy volunteers

Optimization of Blood Levels of 25(OH)-Vitamin D in African Americans

ClinicalTrials.gov ID: NCT04939792

Public ClinicalTrials.gov record NCT04939792. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 6, 2026, 11:00 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

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.

Study identification

NCT ID
NCT04939792
Recruitment status
Completed
Study type
Interventional
Phase
Early Phase 1
Enrollment
165 participants

Conditions and interventions

Eligibility (public fields only)

Age range
18 Years to 65 Years
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Nov 5, 2020
Primary completion
Oct 30, 2022
Completion
Oct 30, 2022
Last update posted
Jun 7, 2023

2020 – 2022

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Louisiana State University Health Shreveport Shreveport Louisiana 71103

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT04939792, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Jun 7, 2023 · Synced Sep 6, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT04939792 live on ClinicalTrials.gov.

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