F, the Omicron subvariant that now accounts for most new cases in the United States, The Associated Press reports.
The Food and Drug Administration announced that the antibody drug sotrovimab is no longer authorized to treat patients in U.S. states or territories. The decision was expected, as the FDA restricted the drug’s use across the country throughout March as BA.2 became dominant in certain regions, the AP reported.
The BA.2 subvariant now accounts for 72% of new COVID-19 cases sequenced by health authorities, according to the latest CDC data updated April 5. The FDA cited the CDC data in its reason for pulling back on the authorization of the drug.
The GlaxoSmithKline drug is the latest antibody medication to be pulled due to coronavirus mutations. In January, the FDA halted the use of antibody drugs from Regeneron and Eli Lilly because they didn’t work against the Omicron variant.
The FDA’s decision means that one antibody drug is still authorized for use against routine COVID-19 cases, the AP reported. A different Eli Lilly drug – bebtelovimab – still appears to work against BA.2.
Doctors can also prescribe antiviral pills, which typically affect the coronavirus spike protein and aren’t affected by mutations, to treat mild to moderate COVID-19, the AP reported. The authorized pills from Pfizer and Merck – Paxlovid and Lagevrio – have been shipped to pharmacy chains and medical clinics in hopes of getting them to patients early enough to work.
The federal government purchased nearly $2 billion worth of the GlaxoSmithKline drug and shipped more than 900,000 doses to states last fall, the AP reported. In March, the company announced that it was studying a higher dose that could be effective against BA.2, which would require FDA approval before resuming use in the United States.
The antibody drugs mimic the virus-blocking proteins found in the human body, the AP reported. They’re designed to attack a specific virus and need to be updated as the coronavirus mutates.
A version of this article first appeared on WebMD.com.