The RECOVERY trial, a large, controlled, open-label study, investigated the effect of dexamethasone on 28-day mortality in hospitalized patients with Covid-19. A total of 2104 patients received dexamethasone, while 4321 received usual care. The primary outcome was 28-day mortality, with results showing that dexamethasone reduced mortality by 22.9% compared to 25.7% in the usual care group (rate ratio, 0.83; 95% CI, 0.75 to 0.93; P<0.001). The benefit was most pronounced in patients receiving invasive mechanical ventilation (29.3% vs. 41.4%) and those receiving oxygen without invasive ventilation (23.3% vs. 26.2%), but not in those receiving no respiratory support (17.8% vs. 14.0%). The trial also found that dexamethasone reduced the duration of hospitalization and the risk of requiring invasive mechanical ventilation in patients not receiving respiratory support. However, there was no benefit in patients not requiring oxygen. The study highlights the importance of respiratory support status in determining the effectiveness of dexamethasone. The trial was conducted in the UK and was supported by the National Institute for Health Research. The results have led to the recommendation of dexamethasone for hospitalized patients with Covid-19 requiring respiratory support. The study underscores the need for further research to understand the mechanisms behind the observed effects and to determine the optimal use of dexamethasone in different patient populations. The findings are significant in the context of the ongoing pandemic and provide important insights into the treatment of severe cases of Covid-19.The RECOVERY trial, a large, controlled, open-label study, investigated the effect of dexamethasone on 28-day mortality in hospitalized patients with Covid-19. A total of 2104 patients received dexamethasone, while 4321 received usual care. The primary outcome was 28-day mortality, with results showing that dexamethasone reduced mortality by 22.9% compared to 25.7% in the usual care group (rate ratio, 0.83; 95% CI, 0.75 to 0.93; P<0.001). The benefit was most pronounced in patients receiving invasive mechanical ventilation (29.3% vs. 41.4%) and those receiving oxygen without invasive ventilation (23.3% vs. 26.2%), but not in those receiving no respiratory support (17.8% vs. 14.0%). The trial also found that dexamethasone reduced the duration of hospitalization and the risk of requiring invasive mechanical ventilation in patients not receiving respiratory support. However, there was no benefit in patients not requiring oxygen. The study highlights the importance of respiratory support status in determining the effectiveness of dexamethasone. The trial was conducted in the UK and was supported by the National Institute for Health Research. The results have led to the recommendation of dexamethasone for hospitalized patients with Covid-19 requiring respiratory support. The study underscores the need for further research to understand the mechanisms behind the observed effects and to determine the optimal use of dexamethasone in different patient populations. The findings are significant in the context of the ongoing pandemic and provide important insights into the treatment of severe cases of Covid-19.