Regeneron Pharmaceuticals’ COVID-19 antibody cocktail reduces deaths in hospitalised patients who have not mounted their own antibody response, a large British study published on Wednesday found.
The therapy, REGEN-COV, has been granted emergency use authorisation for people with mild-to-moderate COVID-19 in the United States, but results from the RECOVERY trial provide the clearest evidence of its effectiveness among hospitalised patients.
It found that the antibody therapy reduced by a fifth the 28-day mortality of people admitted to hospital with COVID-19 whose immune system had not mounted an antibody response, known as seronegative.
The result translates into six fewer deaths for every 100 seronegative patients treated with the therapy, researchers said.
There was no discernible effect of the treatment on those who had generated natural antibody responses and were seropositive.
“People have been very, very sceptical, that any treatment against this particular virus would work by the time people get in hospital,” Martin Landray, the joint chief investigator on the trial, told reporters.
“If you haven’t raised antibodies of your own, you really would benefit from getting some,” he said.
The treatment also shortened the hospital stay of those who were seronegative and reduced their chances of needing a mechanical ventilator, Landray said.
