Since the emergence of COVID-19 in late 2019, researchers have evaluated several therapeutic agents, but no antiviral agent has been shown to be efficacious in the treatment of the virus. Researchers conducted a randomized, double-blind, placebo-controlled trial of the antiviral remdesivir for the treatment of patients hospitalized with COVID-19.

A total of 1,062 patients (mean age, 58.9 years; 64.4% were male) were randomly assigned to either intravenous remdesivir or placebo. The researchers assessed patients' clinical status daily using an eight-category ordinal scale and the National Early Warning Score, on which higher scores indicate greater clinical risk.

The median time to recovery was 10 days for patients assigned to remdesivir, compared with 15 days for those who received placebo. The benefit was greater when remdesivir was given earlier in the illness. The odds of clinical improvement on the ordinal scale were higher in the remdesivir group than in the placebo group, after adjustment for disease severity. Compared with the placebo group, the remdesivir group also had lower mortality estimates at day 15 (6.7% versus 11.9%) and day 29 (11.4% versus 15.2%). Patients who had a baseline ordinal score of 5 (receiving low-flow oxygen) showed the greatest benefit from remdesivir use. Serious adverse events occurred in 24.6% of patients receiving remdesivir compared with 31.6% of those receiving placebo.

The researchers note that high mortality rates in COVID-19 patients persist despite the use of remdesivir, pointing to the need for ongoing investigations into the use of combination therapies to improve outcomes in these patients.

As we went to press: On November 20, after considering the results of several studies, the World Health Organization announced a conditional recommendation against remdesivir's use in hospitalized patients, saying that the medication has "no important effect on mortality, need for mechanical ventilation, time to clinical improvement, and other patient-important outcomes."