Post-exposure protection of SARS-CoV-2 lethal infected K18-hACE2 transgenic mice by neutralizing human monoclonal antibody

A monoclonal antibody MD65 was previously generated from lymphocytes collected from SARS-CoV-2 infected individual, which has been shown to exhibit a high neutralization potency in vitro. In this report, authors showed the efficacy of this antibody in vivo by using K18-hACE2 transgenic mice which are highly suceptible to SARS-CoV-2 infection whose phenotype is characterized by significant viral load in the lungs, heart, brain and spleen, as well as mortality. The prophylactic treatment of MD65 against virus-infected mice was effective to protect the animals from lethal infection. Moreover, authors demonstrated that protection was effective in the post-treatment of antibody at least 4 days postinfection.