The US drugs regulator has rescinded its authorisation for the monoclonal antibody treatments made by Eli Lilly and Regeneron, which proved highly effective at fighting earlier strains of Covid-19 but have been shown not to work well against the Omicron variant.
The Food and Drug Administration announced on Monday it was removing its approval for doctors to use the treatments, which work by injecting patients with proteins which mimic the body’s immune response.
Dr Patrizia Cavazzoni, director of the FDA’s Center for Drug Evaluation and Research, said in a statement: “Because data show these treatments are highly unlikely to be active against the Omicron variant, which is circulating at a very high frequency throughout the United States, these treatments are not authorised for use in any US states, territories, and jurisdictions at this time.”
The treatment made by Regeneron was credited with helping Donald Trump recover quickly from the virus when he was infected in 2020. But federal agencies have discouraged their use as Omicron has become the dominant strain in the US, saying it is not worth exposing patients to potential side-effects.
That has triggered a row with Ron DeSantis, the Republican governor of Florida, however, who has accused the Biden administration of “playing games” with the therapies by restricting their supply.