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NCT01633177 · ClinicalTrials.gov registry record · Phase 3
Study of Vitamin D and Omega-3 Supplementation for Preventing Diabetes
A Phase 3 study, sponsored by Brigham and Women's Hospital.
- Completed
- Registry status
- Phase 3
- Development phase
- 22,220
- Enrollment target
NCT01633177: Completed Phase 3 study, sponsored by Brigham and Women's Hospital.
NCT01633177 is a Phase 3 study that has completed, run by Brigham and Women's Hospital. The registered enrollment target is 22,220 participants, above the 771-participant average among 15,282 other Phase 3 trials with a reported enrollment target (2782% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT01633177, a Phase 3 study, has completed, sponsored by Brigham and Women's Hospital.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 22,220 participants
- Enrollment target
Study Summary
The VITamin D and OmegA-3 TriaL (VITAL; NCT 01169259) is an ongoing randomized clinical trial in 25,875 U.S. men and women investigating whether taking daily dietary supplements of vitamin D3 (2000 IU) or omega-3 fatty acids (Omacor® fish oil, 1 gram) reduces the risk of developing cancer, heart disease, and stroke in people who do not have a prior history of these illnesses. This ancillary study is being conducted among nondiabetic participants in VITAL and will examine whether vitamin D or fish oil prevent type 2 diabetes. Findings from this ancillary study (n=22220 without diabetes at baseline) conducted within the VITAL trial will clarify whether vitamin D and omega-3 fatty acid supplementation reduces risk of type 2 diabetes and thus will inform public health and clinical guidelines for diabetes prevention.
Primary Outcome
Incident type 2 diabetes during follow-up
Interventions
- DIETARY_SUPPLEMENT Vitamin D3
- DIETARY_SUPPLEMENT Vitamin D3 placebo
- DRUG Fish oil placebo
- DRUG Omega-3 fatty acid (fish oil)
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 22,220 participants |
| Start Date | 2011-11 |
| Est. Completion | 2024-05-30 |
| Phase | Phase 3 |
What the finished NCT01633177 record still lists
NCT01633177 is an interventional study that assigns participants to a tested intervention. Its 22,220 participants enrollment target places it among the larger protocols in the corpus, above the 771-participant average among 15,282 other Phase 3 trials with a reported enrollment target (2782% higher).
The record links to 0 conditions, and to 4 interventions - of which Vitamin D3 is the first listed.
NCT01633177 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT01633177 about?
NCT01633177 is a clinical study titled "Study of Vitamin D and Omega-3 Supplementation for Preventing Diabetes". The VITamin D and OmegA-3 TriaL (VITAL; NCT 01169259) is an ongoing randomized clinical trial in 25,875 U.S. men and women investigating whether taking daily dietary supplements of vitamin D3 (2000 IU) or omega-3 fatty acids (Omacor® fish oil, 1 gram) reduces the risk of developing cancer, heart dis...
What is the current status of trial NCT01633177?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 22,220 participants. The study started on 2011-11. Estimated completion is 2024-05-30.
What interventions are being tested in trial NCT01633177?
The interventions under investigation include: Vitamin D3 (DIETARY_SUPPLEMENT), Vitamin D3 placebo (DIETARY_SUPPLEMENT), Fish oil placebo (DRUG), Omega-3 fatty acid (fish oil) (DRUG).
Who is sponsoring clinical trial NCT01633177?
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 NCT01633177's enrollment target sits among peer trials
22,220 9th of 2000 higher than 1,992 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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