Monoclonal antibody mix cuts deaths of hospitalised Covid patients by a fifth: Recovery trial

Aditi Tandon
Tribune News Service
New Delhi, June 16

In a landmark development on Wednesday, the University of Oxford led Recovery Trials working to search Covid-19 treatments said they had for the first time found an antiviral treatment saving lives of hospitalised patients.

The Randomised Evaluation of Covid-19 Therapy (RECOVERY) trial demonstrated that the investigational antibody combination developed by the US biotechnology giant Regeneron reduced the risk of death by a fifth when given to patients hospitalised with severe Covid-19 who have not mounted a natural antibody response of their own.

The treatment uses a combination of two monoclonal antibodies (casirivimab and imdevimab, known as REGEN-COV in the US) that bind specifically to two different sites on the coronavirus spike protein, neutralising the ability of the virus to infect cells.

Previous studies in non-hospitalised Covid-19 patients have shown that the treatment reduces viral load, shortens the time to resolution of symptoms, and significantly reduces the risk of hospitalization or death.

In a small trial in hospitalised patients, preliminary evidence suggested a clinical benefit in patients who had not mounted a natural antibody response of their own when they entered the trial (were seronegative).

Recovery is the first trial large enough to determine definitively whether this treatment reduces mortality in patients hospitalised with severe Covid-19.

Between September 18, 2020, and May 22, 2021, 9785 patients hospitalised with Covid-19 were randomly allocated to receive usual care plus the antibody combination treatment.

Among patients who were seronegative (had no antibodies of their own) the antibody combination significantly reduced the primary outcome of 28-day mortality by one-fifth compared with usual care alone (24 pc of patients in the antibody combination group died versus 30 pc patients in the usual care group).

Thus, for every 100 such patients treated with the antibody combination, there would be six fewer deaths, the Recovery Trial reported on Wednesday.