CI

At a glance

ClinicalIndex Comparison Record
N/ACompleted· 1,475 enrolled
Drug / intervention
Vitamin D3dietary
Likely dose
Not stated in record
Structured eligibility isn't available for this trial yet — see the full criteria in the Eligibility tab below.

Standardized by ClinicalIndex from the ClinicalTrials.gov record · verify against the source.

Search/NCT04868903
NCT04868903N/ACompleted

Low vs. Moderate to High Dose Vitamin D for Prevention of COVID-19

University of Chicago·interventional·Posted May 3, 2021·Updated Feb 20, 2026

In Brief

A clinical study evaluating Vitamin D3 for SARS-CoV-2 Infection. Completed, enrolled 1,475 participants across 2 sites.

Detailed Summary

The purpose of this study is to compare the risks of COVID-19 in individuals from Chicagoland communities randomized to low (400 IU/day) vs. moderate (4,000 IU/day) or high (10,000 IU/day) dose vitamin D.

Study Details

Study Typeinterventional
Allocation--
Masking--
Primary Purpose--
CountriesUnited States

Timeline

N/ACompletedFinished
202120222023202420252026
First PostedMay 3, 2021
Enrollment StartNov 30, 2020
Primary CompletionDec 1, 2024
TodayJul 2, 2026
Enrollment to primary: 4.0 yearsPosted 5.2 years ago

Interventions

Vitamin D3dietary

Half the subjects will be randomized to the low dose vitamin D therapy (400 IU/day), which will serve as the control group, and half to moderate (4,000 IU/day) or high (10,000 IU/day). Study participants will have the option between being randomized to the low versus moderate or the low versus high dose arms.