Cholecalciferol to Improve the Outcomes of COVID-19 Patients

The recent inception of the coronavirus SARS-CoV-2, responsible for the coronavirus disease (COVID-19), has caused thousands of deaths globally. The most frequently reported complications among COVID-19 patients are from respiratory involvement. Vitamin D has immunomodulatory effects that could protect against COVID-19 infection. Indeed, there is good evidence from randomized clinical trials suggesting that high doses of vitamin D administered during cold seasons prevent viral respiratory infections in at risk individual, and more recently, observational studies suggested that the mortality rate from COVID-19 is inversely correlated with levels of serum 25(OH)vitamin D. The hypothesis of the study is that a high dose of vitamin D given orally to patients admitted to the hospital for COVID-19 will prevent the occurrence of respiratory deragement and other adverse clinical events. To evaluate the aforementioned hypothesis, a randomized, controlled, double-blind, clinical trial comparing a 500.000 UI dose of vitamin D versus placebo among COVID-19 patients at moderate risk, requiring hospitalization but without requirements of critical care at admission was designed. The intervention will be one dose of 500.000 UI given orally or matching placebo. The trial has a sequential design with two steps: * The first step, projected to include 200 patients, will assess the effects of the intervention on the respiratory SOFA; and * If there is a detectable effects, the second step, projected to include 1264 patients, will assess the effects on a combined event that includes need of high dose of oxygen or mechanical ventilation. All study outcomes will be measured during the index hospitalization.