Until Friday, just one COVID-19 antibody drug has been effective against the Omicron variant – sotrovimab from Vir Biotechnology and GSK – and that drug is unlikely to do as well against at least one new version of the variant spreading globally, new research suggests.
An antibody drug approved on Friday by the U.S. Food and Drug Administration does show promise when tested against “sublineages,” or subvariants, of Omicron, the research found.
The World Health Organization is monitoring several Omicron subvariants.
Data posted on Wednesday on bioRxiv ahead of peer review showed that the rapidly spreading BA.2 subvariant “exhibited marked resistance” to sotrovimab in lab experiments, researchers said.
Britain-based GSK announced on Thursday, without formally releasing any data, that its drug does retain the ability to neutralize BA.2 in a test tube.
David Ho of Columbia University, senior author of the bioRxiv report, said his research “also showed that sotrovimab still has activity against BA.2, consistent with their statement.
But its activity is down substantially, 27-fold as stated in our preprint.” In repeat experiments, the drop was even more pronounced, he said of testing done after the paper was submitted.
The drug approved on Friday – bebtelovimab, from Eli Lilly, remained potent in neutralizing all Omicron subvariants, Ho’s team said.
Two antibody drugs from AstraZeneca – cilgavimab and tixagevimab – did remain effective against BA.2, but they are only approved for preventing COVID-19 in certain circumstances, not for treating it.
