In a large, multinational trial, the antiviral drug remdesivir reduced recovery time in patients hospitalized with severe COVID-19 by about one-third. The trial was conducted by the Adaptive COVID-19 Treatment Trial Study Group, a collaboration that included researchers from the University of Washington Schools of Medicine and Public Health.
“The main take-home messages are that remdesivir is effective in reducing the duration of illness in people who are hospitalized with COVID-19—but it’s obviously not a cure-all," said study co-author Helen Chu, an assistant professor of allergy and infectious diseases at the UW School of Medicine and adjunct associate professor of epidemiology and global health at the UW School of Public Health.
Preliminary results were published May 22 in the New England Journal of Medicine, after a review by independent experts overseeing the trial's safety determined that patients who received the drug were clearly benefiting. Remdesivir inhibits the virus’s ability to replicate by interfering with its ability to make copies of its RNA genome.
"There was still a very high mortality in both groups. It gives us something to work with, but we will need other treatments on top of this antiviral to really improve outcomes," Chu said.
The study enrolled 1,063 high-risk patients who were hospitalized in medical centers in North America, Europe and Asia, and who had laboratory-confirmed COVID-19 infections and evidence that the infection had reached their lungs. Their average age was 58.9 years, and 64.3% were men. Most had at least one or more chronic conditions that have been linked to poorer outcomes with COVID-19, such as high blood pressure, obesity and type 2 diabetes.
In the study, patients were randomly assigned to one of two groups: 541 were assigned to receive remdesivir daily for 10 days and 522 were assigned to receive a placebo. Neither the clinicians nor the patients knew who was receiving the placebo or the active drug.
The interim analysis found that patients who had received remdesivir had a median recovery time of 11 days, compared with 15 days for those on the placebo. A patient was considered to have recovered if they could be discharged from the hospital or remained in the hospital but required no further medical care—such as patients who could not return to nursing homes because of caution toward the disease.
The death rate was also less among those who received the drug (7.1%) than among those in the placebo group (11.9%), but the difference was not statistically significant. Serious events were slightly higher among those on placebo but, again, the difference was not statistically significant. The investigators reported no deaths related to the drug treatment.
Benefit was observed both in patients that had been sick for shorter and longer durations before receiving the drug. The greatest benefit was seen in patients with disease severe enough to require supplemental oxygen, but not so ill that they required a ventilator or extracorporeal membrane oxygenation, a treatment in which the patient’s blood is circulated through an artificial lung to maintain adequate oxygen.
Anna Wald, a professor of medicine and laboratory medicine at the UW School of Medicine and professor of epidemiology at the UW School of Public Health, said it is important be mindful that this is an interim analysis.
“We will soon have a more complete analysis of the data from all the patients, and when that is done we might see other benefits and be better able to define which groups of patients benefit the most,” Wald said.