Bamlanivimab is the recombinant version of an antibody (monoclonal antibody) that received emergency approval by the Food and Drug Administration (FDA) in the US in November 2020 for the treatment of mild to moderate COVID-19 disease. Bamlanivimab is an antibody that was discovered in the blood of one of the first US COVID-19 patients at the beginning of the pandemic. The antibody was chosen from among 500 different antibodies from the patient because it recognizes the section of the spike protein that SARS-CoV-2 uses to dock with human cells. This blocks the virus from entering human cells. After isolating the B cells, the coding gene was incorporated into recombinant cells. This allows the antibody to be produced in cell cultures in unlimited quantities. It is administered by intravenous infusion.
After the antibody significantly reduced viral load in animal studies in primates and was shown to be safe in a phase 1 study in clinic patients with COVID-19, a phase 2 study in humans was conducted on June 17. In this study (BLAZE-1 trial), bamlanivimab significantly reduced the proportion of patients who were subsequently hospitalised from 6.3% to 1.6% in outpatients with a mean symptom onset of 4 days ago and who were only mildly ill. Bamlanivimab has not yet been shown to be effective in people who are already severely ill.