Immune-evasive Omicron subvariant XBB rapidly gaining ground in U.S.
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The emerging Omicron subvariant XBB contributes to an increasingly high number of COVID-19 cases in the U.S., rivaling the sister strains BQ.1.1 and BQ.1, according to the latest estimates from the Centers for Disease Control and Prevention (CDC).
Recent studies have indicated that the updated bivalent COVID-19 booster performed poorly against BQ.1.1, with even a weaker antibody response against XBB.
In late November, citing its poor neutralization effect on BQ.1 and BQ.1.1., the FDA pulled the emergency use authorization granted for bebtelovimab, a COVID-19 antibody therapy developed by Eli Lilly (LLY) and AbCellera Biologics (ABCL).
The CDC estimates for the week ending Dec. 24 show that BQ.1.1 has led to ~36% of COVID cases in the U.S., unchanged from a week ago, and BQ.1 caused ~27% of cases, a decline from ~29% last week. However, for the latest period, XBB.1 has made up ~18% of cases compared to ~11% a week ago.
COVID vaccine makers: Pfizer (NYSE:PFE)/ BioNTech (BNTX), Moderna (MRNA), Johnson & Johnson (JNJ) and Novavax (NVAX)
Makers of COVID-19 pills: Pfizer (PFE), Merck (MRK)
Against a backdrop of a rapidly mutating virus, a group of FDA experts is scheduled to meet next month to discuss how to update currently available COVID-19 vaccines and boosters.