June 24, 2021

RECOVERY Trial: The REGN-COV Antibody Cocktail in COVID19

Background: Antibodies targeted at the SARS-CoV2 spike protein are an essential part of the body’s immune response to COVID19 infection. Infection with SARS-CoV2 stimulates the immune system to produce a polyclonal spike protein antibody response in the host. Vaccines have similar results and recent studies show that the antibody response is even more robust than with natural infection. These antibodies bind to numerous locations on the SARS-CoV2 spike protein limiting the virus’s ability to enter and infect host cells. 

One of the many massive challenges of the COVID19 pandemic has been the lack of targeted therapeutics. Extensive efforts have been invested into research with only glimmers of benefit for most drugs. The exception to this has been dexamethasone which was shown in the RECOVERY trial to have remarkable impacts on death in patients requiring O2 (NNT = 29) and in those requiring invasive ventilation (NNT = 8.5).  The RECOVERY Group has continued to perform excellent research but most of the investigated therapeutics including azithromycin, convalescent plasma, aspirin and colchicine have all fallen flat.

Monoclonal antibody infusions have gained national attention as a potential therapeutic in COVID patients and have been touted by medical experts. The goal of these drugs is to give patients antibodies prior to their body mounting a response in an effort to prevent progression of disease. We have previously reviewed the EUA drug bamlanivimab (LY-CoV555) - a monoclonal antibody. In that review, we note the absence of any difference in patient centered outcome as well as serious methodological flaws. We have also reviewed REGN-COV2 (casirivimab/imdevimab) noting the lack of any evidence of benefit as well as the suspect methodology. In January, in a post for Brief 19, I concluded that “there is no convincing data that monotherapy or a cocktail of antibodies improves meaningful outcomes in patients with COVID19.” However, the RECOVERY group has submitted a new study that was released as a preprint on June 16th, 2021.