The U.S. Food and Drug Administration (FDA) has issued an emergency use authorization for bebtelovimab, a new monoclonal antibody designed to reduce risk of hospitalization and death from COVID-19. The approval comes weeks after the FDA halted use of previously authorized antibody treatments following research that revealed them to be ineffective against the Omicron variant of SARS-CoV-2.
Bebtelovimab is a novel monoclonal antibody developed by biotech company AbCellera in collaboration with pharma giant Eli Lilly and Company (Lilly). The research team behind the innovation was previously responsible for one of the first monoclonal antibody treatments for COVID-19, called bamlanivimab, which was authorized for use in late 2020.
Carl Hansen, CEO of AbCellera, said development of the newer monoclonal treatment began back in early 2021 before any serious SARS-CoV-2 variant had emerged. In an attempt to get ahead of future variants, the researchers focused on developing an antibody that binds to particular regions of the SARS-CoV-2 spike protein thought to only very rarely mutate.
“We shifted our efforts to discovering a next-generation antibody therapeutic, this time prioritizing maximum potency and breadth of neutralization,” explained Hansen. “This resulted in the discovery of bebtelovimab, which neutralizes all known variants of concern, and is the most potent antibody in development against the Omicron variant, including BA.2.”
The FDA’s emergency use authorization (EUA) of bebtelovimab comes with a number of significant limitations. It can only be given to those over the age of 12 experiencing mild to moderate symptoms in the early stages of COVID-19.
Bebtelovimab is not authorized for use in patients already hospitalized with COVID-19, and it is only recommended in patients, “for whom alternative COVID-19 treatment options approved or authorized by the FDA are not accessible or clinically appropriate.”
The EUA comes just weeks after the US government halted its use of two other monoclonal antibody treatments. Lilly’s prior treatment (bamlanivimab and etesevimab) and Regeneron’s infamous antibody cocktail were both found to be ineffective at treating COVID-19 cases with the Omicron variant.
This recently left healthcare providers with few options to treat high-risk COVID-19 patients. Antivirals such as Pfizer’s Paxlovid and Merck’s molnupiravir are still expected to work against the Omicron variant but only one monoclonal antibody treatment is thought to remain effective – sotrovimab.
While sotrovimab may still work against BA.1, the primary iteration of Omicron currently spreading around the world, recent research indicates it may not be effective against BA.2, another form of Omicron that is growing in prevalence. It is still unclear how well sotrovimab holds up against BA.2 but if it does prove to be ineffective then doctors will be increasingly limited in their tools to fight COVID-19.
AbCellera and Lilly both claim preliminary lab studies show bebtelovimab is effective against all current SARS-CoV-2 variants, including Omicron iterations BA.1 and BA.2. The US government has entered into a purchase agreement with Lilly for 600,000 doses of bebtelovimab, to be delivered over the next two months.
“Should the BA.2 subvariant grow in proportion in the U.S., this potential treatment may help ensure that we can continue to offer monoclonal antibody treatment that works against that strain of the virus,” the U.S. Department of Health and Human Services said in a recent statement.
