The efficacy and safety of corticosteroids in patients with viral pneumonia remains largely uncertain because of a scarcity of randomized trials and inconclusive observational studies. At the onset of the pandemic, there was equipoise regarding use of corticosteroids for severe COVID-19. Corticosteroids may impair immune defenses and hamper viral clearance, potentially leading to subsequent excess mortality such as has been suggested in patients with severe influenza. Yet one observational study reported that methylprednisolone was associated with a 25% relative reduction in short term mortality among patients with COVID-19–related acute respiratory distress syndrome. Recently, an open-label randomized trial found that dexamethasone improved day-28 survival in patients hospitalizedwithCOVID-19. The purpose of this study was to evaluate the effect of hydrocortisone for the treatment of ICU patients with COVID-19–related acute respiratory failure.