•Higher-dose corticosteroids increased the risk of death in patients with COVID-19 and hypoxia, compared with usual care that included low-dose corticosteroids.
• Among over 1,200 patients, 18% of those randomly assigned to higher-dose dexamethasone died within 28 days compared with 12% of those assigned to usual care.
• More patients in the higher-dose group required invasive mechanical ventilation or died -- a key secondary outcome -- compared with the usual care group.