Regeneron’s Combination Antibody Therapy Reduces Risk of COVID-19 Mortality

The results of the randomized evaluation trial of COVID-19 therapy (RECOVERY) showed that Regeneron’s experimental antibody combination therapy reduces the risk of mortality for hospitalized patients with severe COVID-19 whose immune response did not start naturally. The results of the trial were published in a press release dated June 16, 2021.

Regeneron’s combination therapy includes two monoclonal antibodies, casirivimab and imdevimab, which specifically bind to two different sites on the coronavirus spike protein. In previous studies in outpatients, treatment has been shown to reduce viral load, shorten the time to symptom resolution, and significantly reduce the risk of hospitalization or death.

Preliminary results from a small inpatient trial suggested that the combination therapy would provide clinical benefit in inpatients who had not developed a natural immune response (HIV negative). The RECOVERY trial included 9,785 patients hospitalized for COVID-19, representing a patient population large enough to determine whether treatment reduces mortality.

Of the patients included in the trial, about a third were HIV negative at baseline. For these patients, the combination therapy was found to significantly reduce the primary endpoint of 28-day mortality. This result was not comparable with patients who were initially seropositive.

“These results are very exciting. The hope was that by giving a combination of antibodies targeting the SARS-CoV-2 virus, we would be able to reduce the worst manifestations of COVID-19. There was, however, great uncertainty about the value of antiviral therapies in late stage COVID-19 disease, ”said Sir Peter Horby, professor of emerging infectious diseases in the Nuffield Department of Medicine, University of Oxford , and joint lead investigator for the RECOVERY trial, in the press release. “It’s wonderful to learn that even in advanced cases of COVID-19 disease, targeting the virus can reduce mortality in patients who have failed to develop their own antibody response.”

“We now know that this combination of antibodies is not only bad for the virus, but it is also good for sicker patients who have failed to develop their own natural immune response,” added Sir Martin Landray, professor of medicine and epidemiology at the Nuffield Department of Population Health, University of Oxford, and joint chief investigator, in the press release. “This is great news, this is the first time that antiviral treatment has saved lives in hospitalized patients with COVID-19. We are extremely grateful to the many NHS staff and patients who contributed to today’s discovery. “

Source: Oxford University