A research team at the University of North Carolina – Chapel Hill (UNC) and Duke University, in Durham, NC identified an antibody that attacks SARS-CoV-2 and its variants and other types of coronaviruses.
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A research team at the University of North Carolina – Chapel Hill (UNC) and Duke University, in Durham, NC, identified an antibody that attacks SARS-CoV-2, the virus that causes COVID-19, but also its variants and other types of coronaviruses. In their studies, the antibody, DH1047, works at preventing infection and fighting it after a person is diagnosed with COVID-19.
The investigators isolated two other antibodies that worked against some types of coronaviruses that infect animals and humans, but not all. These were DH1235 and DH1073. DH1073 was only effective against SARS-CoV-2.
“This antibody (DH1047) has the potential to be a therapeutic for the current epidemic,” said Barton Haynes, M.D., director of Duke Human Vaccine Institute and co-author of the study. “It could also be available for future outbreaks, if or when other coronaviruses jump from their natural animal hosts to humans.”
The new antibody was isolated from the blood of a patient infected with SARS in early 2000. That illness is caused by SARS-CoV-1, a close relative of the coronavirus, SARS-CoV-2, that causes COVID-19. They also isolated it from a current COVID-19 patient.
In their research, they identified more than 1,700 antibodies from the two individuals. Of them, 50 could bind to SARS-CoV-1 and SARS-CoV-2. Then they discovered that one of those cross-binding antibodies was particularly potent, able to attach to a range of coronaviruses as well as to SARS-C0V-1 and 2.
“This antibody binds to the coronavirus at a location that is conserved across numerous mutations and variations,” Haynes said. “As a result, it can neutralize a wide range of coronaviruses.”
The UNC team was led by co-senior author Ralph S. Baric, Ph.D., William R. Kenan, Jr. Distinguished Professor of epidemiology at the UNC Gillings School of Global Public Health. That group tested DH1047 in mice to see if it could block infections or minimize ongoing infections. It did both. Not only did it prevent the mice from developing SARS and COVID-19, but it also prevented variants such as Delta and other animal coronaviruses.
“The findings provide a template for the rational design of universal vaccine strategies that are variant-proof and provide broad protection from known and emerging coronaviruses,” Baric said.
In animals with severe lung symptoms, treatment with the antibody decreased the symptoms compared to the control group.
“The therapeutic activity even after mice were infected suggests that this could be a treatment deployed in the current pandemic, but also stockpiled to prevent the spread of a future outbreak or epidemic with a SARS-related virus,” said David Martinez, Ph.D., co-lead author and a postdoctoral researcher in the Department of Epidemiology at UNC’s Gilling School. “This antibody could be harnessed to prevent maybe SARS-COV-3 or SARS-CoV-4.”
Alexandra Schaefer, Ph.D., assistant professor of epidemiology at Gillings, is also a co-lead author.
The research was published in the journal Science Translational Medicine.
The U.S. Food and Drug Administration (FDA) has granted Emergency Use Authorization (EUA) to three monoclonal antibody therapies against COVID-19. They are Eli Lilly’s bamlanivimab plus etesevimab, Regeneron Pharmaceuticals’ Regen-Cov (casirivimab plus imdevimab) and Vir Biotechnology and GlaxoSmithKline’s sotrovimab.
On October 11, AstraZeneca reported high-level results from its Phase III TACKLE trial of its AZD7442, a long-acting antibody (LAAB) combination in COVID-19. The cocktail hit a statistically significant decrease in severe COVID-19 or death compared to placebo in non-hospitalized patients with mild to moderate symptomatic COVID-19.
In a prespecified analysis of patients receiving the treatment within five days of symptoms appearing, the cocktail decreased the risk of severe COVID-19 or death by 67% compared to placebo. It is administered by an intramuscular injection, which is significantly more convenient than other antibody therapeutics against COVID-19, which require infusions. AstraZeneca submitted a request to the FDA for EUA for the antibody cocktail for prophylaxis of COVID-19 on October 5.
