biostudies-literatureUnknownBishop C<h4>Objective</h4> This double-blind RCT investigated raising serum 25-hydroxyvitamin D (25D) with extended-release calcifediol (ERC) on time to symptom resolution in mild to moderate COVID-19. <h4>Research Methods & Procedures</h4> COVID-19 outpatients received oral ERC (300 mcg on Days 1-3 and 60 mcg on Days 4-27) or placebo (NCT04551911). Symptoms were self-reported daily. Primary endpoints were raising 25D to ≥50 ng/mL and decreasing resolution time for five aggregated symptoms (three respiratory). <h4>Results</h4> 171 subjects were randomized, 160 treated and 134 (65 ERC, 69 placebo) retained. Average age was 43 (range: 18-71), 59% female, mean baseline 25D was 37±1 (SE) ng/mL. In the full analysis set (FAS), 81% of ERC subjects achieved 25D levels of ≥50 ng/mL versus 15% with placeboNutrition (Burbank, Los Angeles County, Calif.)https://www.ebi.ac.uk/biostudies/studies/S-EPMC9639413biostudies-literatureREsCue Trial: Randomized Controlled Clinical Trial with Extended-Release Calcifediol in Symptomatic COVID-19 OutpatientsPMC9639413Federman NStrugnell SKalantar-Zadeh KBishop CVazquez-Escarpanter EChoe JMelnick JNg DAshfaq AAdams JFialkow JfalseREsCue Trial: Randomized Controlled Clinical Trial with Extended-Release Calcifediol in Symptomatic COVID-19 Outpatients<h4>Objective</h4> This double-blind RCT investigated raising serum 25-hydroxyvitamin D (25D) with extended-release calcifediol (ERC) on time to symptom resolution in mild to moderate COVID-19. <h4>Research Methods & Procedures</h4> COVID-19 outpatients received oral ERC (300 mcg on Days 1-3 and 60 mcg on Days 4-27) or placebo (NCT04551911). Symptoms were self-reported daily. Primary endpoints were raising 25D to ≥50 ng/mL and decreasing resolution time for five aggregated symptoms (three respiratory). <h4>Results</h4> 171 subjects were randomized, 160 treated and 134 (65 ERC, 69 placebo) retained. Average age was 43 (range: 18-71), 59% female, mean baseline 25D was 37±1 (SE) ng/mL. In the full analysis set (FAS), 81% of ERC subjects achieved 25D levels of ≥50 ng/mL versus 15% with placebo2022-01-01T00:00:00Z2022 Nov2025-04-05T11:27:24.719Z2025-04-05T11:27:24.719ZS-EPMC9639413