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NCT04536298 · ClinicalTrials.gov registry record · Phase 3
Vitamin D for COVID-19 Trial
A Phase 3 study, sponsored by Brigham and Women's Hospital.
- Completed
- Registry status
- Phase 3
- Development phase
- 2,024
- Enrollment target
NCT04536298: Completed Phase 3 study, sponsored by Brigham and Women's Hospital.
NCT04536298 is a Phase 3 study that has completed, run by Brigham and Women's Hospital. The registered enrollment target is 2,024 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (162% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04536298, a Phase 3 study, has completed, sponsored by Brigham and Women's Hospital.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 2,024 participants
- Enrollment target
Study Summary
The Vitamin D for COVID-19 Trial (VIVID) is a randomized, placebo-controlled clinical trial in 2024 men and women from across the U.S. and Mongolia to investigate whether taking a daily dietary supplement of vitamin D vs. placebo for 4 weeks reduces the rate of seeking healthcare for symptoms or concerns related to COVID-19 in participants recently diagnosed with COVID-19, and reduces the risk of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in household contacts of individuals with newly diagnosed COVID-19.
Interventions
- DIETARY_SUPPLEMENT Placebo
- DIETARY_SUPPLEMENT vitamin D
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 2,024 participants |
| Start Date | 2020-12-28 |
| Est. Completion | 2024-07-01 |
| Phase | Phase 3 |
What the finished NCT04536298 record still lists
NCT04536298 is an interventional study that assigns participants to a tested intervention. Its 2,024 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (162% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT04536298 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04536298 about?
NCT04536298 is a clinical study titled "Vitamin D for COVID-19 Trial". The Vitamin D for COVID-19 Trial (VIVID) is a randomized, placebo-controlled clinical trial in 2024 men and women from across the U.S. and Mongolia to investigate whether taking a daily dietary supplement of vitamin D vs. placebo for 4 weeks reduces the rate of seeking healthcare for symptoms or con...
What is the current status of trial NCT04536298?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 2,024 participants. The study started on 2020-12-28. Estimated completion is 2024-07-01.
What interventions are being tested in trial NCT04536298?
The interventions under investigation include: Placebo (DIETARY_SUPPLEMENT), vitamin D (DIETARY_SUPPLEMENT).
Who is sponsoring clinical trial NCT04536298?
This trial is sponsored by Brigham and Women's Hospital, which has 937 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04536298's enrollment target sits among peer trials
2,024 100th of 2000 higher than 1,901 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 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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