Monoclonal antibody therapy cuts death risk in Covid-19 patients by 20%

Administering monoclonal antibody therapy in severe Covid-19 patients, who have not mounted a natural antibody response of their own, can reduce the risk of death by 20 per cent, according to results of a clinical trial.

Treatment with the therapy, which is a combination of two monoclonal antibodies — Casirivimab and Imdevimab — was touted as a game changer with its better hold on the deadly Covid pandemic by Indian hospitals.

It has also received an emergency use authorisation (EUA) in India by the Central Drugs Standards Control Organisation (CDSCO) in May.

The therapy, developed by US-based biotechnology company Regeneron, is known as REGEN-COV in the US. The antibodies bind specifically to two different sites on the Covid-19 spike protein, neutralising the ability of the virus to infect cells.

The trial, conducted between September 18, 2020 and May 22, 2021, included 9,785 patients hospitalised with Covid-19.

For patients hospitalised with Covid-19 who do not make their own antibodies to the virus, the antibody therapy can reduce their risk of death and time spent in hospital.

On the other hand, the therapy has no benefit on patients who can make their own antibodies to the virus, said researchers adding it “is also important information given the cost of drugs”.

“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,” said Sir Peter Horby, Professor of Emerging Infectious Diseases in the Nuffield Department of Medicine, University of Oxford, and Joint Chief Investigator for the trial, in a statement.

“There was, however, great uncertainty about the value of antiviral therapies in late-stage Covid-19 disease. It is wonderful to learn that even in advanced Covid-19 disease, targeting the virus can reduce mortality in patients who have failed to mount an antibody response of their own,” he added.

The therapy has already received a EUA in the US and several EU countries. Regeneron now aims to share new data with regulatory authorities immediately to request that the US EUA be expanded to include appropriate hospitalised patients, it said.

The therapy is also available in India, and hospitals including Medanta in Gurugram, BLK-Max Super Speciality and Sir Gangaram in New Delhi, have successfully implemented the treatment.