Monoclonal antibody treatments have been developed that reduce the severity of COVID-19; however, the emergence of new variants has limited their effectiveness. Some of the more recent variants are either partially or fully resistant to the monoclonal antibody treatments that have been authorized for use in COVID-19 patients. The current treatments may also be ineffective against future COVID-19 strains and zoonotic SARS-type coronaviruses that have yet to emerge.
A cross-reactive monoclonal antibody treatment is required that will continue to be effective as new SARS-CoV-2 strains emerge and potentially against other coronavirus infections, and a potential candidate has now been identified.
Researchers at the Duke University’s Duke Human Vaccine Institute (DHVI) and the University of North Carolina (UNC) at Chapel Hill identified an antibody that they demonstrated is effective against multiple variants of SARS-CoV-2, SARS-CoV, and a variety of bat coronaviruses.
The antibody was isolated from a blood sample taken from a patient infected with the original SARS-CoV virus and also from a patient recently infected with SARS-CoV-2. In total, more than 1,700 monoclonal antibodies were identified, with 50 of those able to bind to both SARS-CoV and SARS-CoV-2.
The receptor-binding domain (RBD)-specific human antibody, DH1047, was shown to have a neutralizing effect against SARS-CoV, SARS-CoV-2 variants D614G, B.1.1.7, B.1.351, P.1, B.1.429, B.1.526, B.1.617.1, and B.1.617.2, and the bat coronaviruses WIV-1, and RsSHC014. Prophylactic and therapeutic treatment with DH1047 was effective against SARS-CoV, WIV-1, RsSHC014, and SARS-CoV-2 B.1.351 infections in mice.
The antibody binds to a location on coronaviruses that is conserved across numerous mutations and variations, and consequently, it neutralizes a wide range of coronaviruses.
“DH1047 is a broadly protective antibody that can prevent infection and mitigate outbreaks caused by SARS-related strains and SARS-CoV-2 variants,” wrote the researchers. “Our results also suggest that the conserved RBD epitope bound by DH1047 is a rational target for a universal sarbecovirus vaccine.”
You can read more about the research in the paper – A broadly cross-reactive antibody neutralizes and protects against sarbecovirus challenge in mice – which was recently published in Science Translational Medicine. DOI: 10.1126/scitranslmed.abj7125