LONDON – Another potentially life-saving treatment for hospitalized Covid-19 patients has been discovered by researchers at Oxford University.
The UK study – part of the larger RECOVERY study that looked at various possible treatments for people hospitalized with coronavirus – found that an antibody combination made by Regeneron reduced the risk of death when given to patients with severe Covid-19 who have not developed a natural antibody response on their own.
The treatment uses a “cocktail” of two monoclonal antibodies (casirivimab and imdevimab, known in the US as “REGEN-COV”) that specifically bind to two different sites on the coronavirus spike protein and increase the ability of the virus to infect cells , neutralize.
Previous studies in non-hospitalized Covid patients have shown that the treatment lowers viral loads, reduces the time it takes for symptoms to subside, and significantly reduces the risk of hospitalization or death.
But in a small study of hospitalized patients, preliminary evidence suggested a clinical benefit for patients who did not develop their own natural antibody response (i.e., were seronegative) at the start of the study.
This latest study is the first large enough to definitively determine whether this treatment will reduce mortality in patients hospitalized with severe Covid-19.
The study, which took place between September 2020 and May 2021, involved 9,785 patients who were hospitalized with Covid-19.
In patients who were seronegative at baseline, the antibody combination significantly reduced their risk of death by a fifth compared to those who received only the usual treatment (i.e. 24% of patients in the antibody combination group died compared to 30% of patients in the Standard care group).
For every 100 such patients treated with the antibody combination, there would be six fewer deaths.
In addition to reducing the risk of death, the seronegative patients who received the antibody combination treatment were four days shorter in hospital than those who received the usual care and were also less likely to need a ventilator.
In patients who were seropositive at the start of the study, i.e. who had already developed natural antibodies against Covid-19, the treatment had no noticeable positive effect.
The study’s preliminary results, due to be submitted shortly to a leading medical journal, could determine how Covid patients will be treated in the hospital in the future, an expert said.
“This means that patients who are hospitalized with Covid-19 can be divided into two groups depending on whether they have made antibodies to the virus or not,” said Fiona Watt, executive chairman of the UK Medical Research Council , in a statement.
“If you don’t have antibodies, treatment with antibody-based drugs against the spike protein can reduce your risk of death and your time in hospital. Patients who have made their own antibodies to the virus will not benefit from the new treatment, which “is important information given the cost of drugs.”
Peter Horby, Professor of Emerging Infectious Diseases at the University of Oxford’s Nuffield Department of Medicine and Principal Investigator of the RECOVERY study, said the results were “very exciting”.
“The hope was that by giving a combination of antibodies to the SARS-CoV-2 virus, we could reduce the worst manifestations of Covid-19. However, there was great uncertainty about the value of late-stage antiviral therapies.” Covid-19 disease. It is wonderful to learn that even with advanced Covid-19 disease, fighting the virus can reduce mortality in patients who have not built their own antibody response, “he said in a statement.
The RECOVERY study has already made several life-saving discoveries, including that dexamethasone, a cheap and widely used steroid, was able to save lives in seriously ill Covid-19 patients. Last week it released the results of another study that showed that aspirin did not improve survival rates for patients hospitalized with Covid-19 who are at increased risk of blood clots forming in their blood vessels.