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NCT03613116 · ClinicalTrials.gov registry record · Phase 2
High-dose Vitamin D Supplements in Older Adults
A Phase 2 study of Cognitive Decline and Vitamin D Deficiency, sponsored by University of California, Davis.
- Active
- Registry status
- Phase 2
- Development phase
- 180
- Enrollment target
- 1
- Study location
NCT03613116: Active Phase 2 study of Cognitive Decline and Vitamin D Deficiency, sponsored by University of California, Davis.
NCT03613116 is a Phase 2 study of Cognitive Decline and Vitamin D Deficiency that is active but no longer recruiting, run by University of California, Davis. The registered enrollment target is 180 participants, below the 1,146-participant average among 61 other Cognitive Decline trials with a reported enrollment target (84% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03613116, a Phase 2 study of Cognitive Decline and Vitamin D Deficiency, is active but no longer recruiting, sponsored by University of California, Davis.
- ACTIVE NOT RECRUITING
- Registry status
- Phase 2
- Development phase
- 180 participants
- Enrollment target
- 1
- Study location
Study Summary
This Phase II randomized clinical trial aims to test if supplementation with high dose oral vitamin D will successfully correct vitamin D insufficiency, compared to treatment with standard (RDA) dose vitamin D in a diverse community-based elderly cohort. The effect of high-dose vs. standard-dose vitamin D on altering cognitive trajectories will also be assessed and data will be expected to be used in designing a potential definitive Phase III trial in elderly groups at risk for dementia. A total of 180 elderly persons with longitudinal biomarkers, neuropsychological testing and brain MRI scans will be enrolled, with 152 (\~50 with MCI, 50 with mild AD and 50 with no cognitive impairment) expected to complete the 3½-year study. One-half of each diagnostic group will be randomized to treatment with high-dose vitamin D3 (4,000 IU daily) or to standard dose Vitamin D (600 IU capsule daily + \~200 IU dietary = \~800 IU total/day). Longitudinal MRI analyses will provide an estimate of the treatment effect size on brain atrophy rate. Vitamin D receptor genotype polymorphisms and their impact on response to oral supplementation will also be examined. If vitamin D supplementation improves cognitive outcome, this could have a large impact on the public health, since low vitamin D status is a common, readably treatable condition which may provide a novel window to prevent dementia and AD. Furthermore, the higher prevalence of AD and dementia in African Americans and Latinos could be partially attributable to vitamin D insufficiency.
Primary Outcome
Correction of VitD insufficiency in all subjects treated with high dose VitD (defined as serum 25-hydroxyvitamin D ≥ 20.0 ng/ml)
Conditions Studied
Interventions
- DIETARY_SUPPLEMENT Vitamin D3
Study Locations (1)
California
- University of California, Davis Alzheimer's Disease Center - Walnut Creek
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 180 participants |
| Start Date | 2019-03-18 |
| Est. Completion | 2026-12-31 |
| Phase | Phase 2 |
What the registry record for NCT03613116 still lists
NCT03613116 is an interventional study that assigns participants to a tested intervention. The registered 180 participants enrollment target is mid-sized for trials with a published cap, below the 1,146-participant average among 61 other Cognitive Decline trials with a reported enrollment target (84% lower).
The record links to 2 conditions, with Cognitive Decline appearing as the primary indexed condition, and to 1 intervention - of which Vitamin D3 is the first listed.
NCT03613116 reports a single indexed study location in California.
Frequently Asked Questions
What is clinical trial NCT03613116 about?
NCT03613116 is a clinical study titled "High-dose Vitamin D Supplements in Older Adults". This Phase II randomized clinical trial aims to test if supplementation with high dose oral vitamin D will successfully correct vitamin D insufficiency, compared to treatment with standard (RDA) dose vitamin D in a diverse community-based elderly cohort. The effect of high-dose vs. standard-dose vit...
What is the current status of trial NCT03613116?
This trial is currently active not recruiting. It is a Phase 2 study. The enrollment target is 180 participants. The study started on 2019-03-18. Estimated completion is 2026-12-31.
What conditions does trial NCT03613116 study?
This clinical trial studies the following conditions: Cognitive Decline, Vitamin D Deficiency.
What interventions are being tested in trial NCT03613116?
The interventions under investigation include: Vitamin D3 (DIETARY_SUPPLEMENT).
Who is sponsoring clinical trial NCT03613116?
This trial is sponsored by University of California, Davis, which has 657 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT03613116 being conducted?
This trial has 1 study location across California. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
Similar trials for Cognitive Decline
Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.
Where NCT03613116's enrollment target sits among peer trials
180 27th of 61 higher than 35 of 61 other Cognitive Decline trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Cognitive Decline 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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