The Food and Drug Administration on Wednesday ended its emergency authorization for the only remaining Covid-19 antibody therapy cleared for use, saying variants that render it ineffective are now dominant in the United States.
The news about bebtelovimab makes official what has been anticipated for several weeks, as the Omicron sublineages BQ.1 and BQ.1.1 have been growing in prevalence. Still, it comes as a blow to both providers and patients who are at risk for more severe outcomes. The rapid evolution of the SARS-CoV-2 virus had already knocked out several other monoclonal antibodies for the treatment of Covid.
Eli Lilly, the maker of bebtelovimab, has stopped the commercial distribution of the treatment, the FDA said. Various companies are working on updated antibody therapies, but none appears close to being authorized.
“Lilly will continue to search [for] and evaluate monoclonal antibodies to identify potential candidates for clinical development against new variants,” the company said in a statement.
Together, the “BQs” — as the two sublineages are known — are causing about 57% of U.S. infections, according to estimates from the Centers for Disease Control and Prevention.
The BQs are also undermining the effectiveness of Evusheld, a type of pre-exposure therapy that provides an extra boost of protection for people who struggle to generate a strong immune response when vaccinated. For now, Evusheld continues to have emergency use authorization from the FDA, though the agency warned last month about the emergence of variants that are not neutralized by Evusheld.
Without bebtelovimab and Evusheld, some 7 million immunocompromised Americans will lose powerful defenses. There are other treatments available, including the oral antiviral Paxlovid, but many people — including transplant recipients — are on medications that can’t be taken at the same time as Paxlovid.
Other treatments are available but have their limitations. Another oral antiviral, Merck’s molnupiravir, is not as effective as Paxlovid. Remdesivir, or Veklury, helps keep people from getting so sick they have to be hospitalized, but it has to be given intravenously over three days — a major inconvenience compared to an oral treatment.
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