The antibody drugs GSK and Regeneron Pharmaceuticals developed against Covid-19 do not appear to work for Omicron and its subvariants, according to a panel of experts advising the World Health Organisation (WHO).
The panel recommended against the use of these medicines.
Its decision comes amid “evidence from laboratory studies that these drugs are not likely to work against currently circulating variants”.
The new guideline is a blow to Regeneron, GSK and its partner Vir Biotechnology, replacing a conditional endorsement of the treatments with a “strong recommendation” against their use.
But it is not entirely surprising: GSK and Vir’s sotrovimab already lost its authorisation in the United States in April because the therapy was unlikely to work against the dominant Omicron BA.2 subvariant.
GSK said in a statement that it is disappointed with the WHO recommendation against its Covid-19 antibody therapy, and that it continues to look for real world evidence on the drug’s effectiveness.
Regeneron said the US Food and Drug Administration in January excluded the use of its Covid-19 antibody cocktail in regions where infections were caused by newer variants, and that the treatment has not been used anywhere in the US for some time.
The company, meanwhile, is working on “next generation” antibodies that can work against current and future variants.
The WHO panel of more than 60 international experts also backed Gilead Sciences’ remdesivir, one of the medicines used at the start of the pandemic, for patients with severe Covid-19, in addition to the prior recommendation for non-severe cases.
The drug still should not be used for critical cases, they said.