The companies said Dec. 2 that they tested the drug, called sotrovimab, against individual mutations found in the Omicron variant, according to The Wall Street Journal. The preliminary findings haven’t yet been peer-reviewed, and the drug will need to be tested against the whole spike protein on the virus to confirm results.
GlaxoSmithKline and Vir have previously tested sotrovimab against mutations on other variants, the newspaper reported. When the Omicron variant was identified, the companies looked at earlier research to find the tests they had done against mutations that are also found in Omicron.
Sotrovimab targets a spot on the spike protein that is found in other coronaviruses and is thought to be less likely to mutate, according to the newspaper. Omicron has at least two mutations that overlap with the drug’s target site, but researchers at the companies don’t think the mutations will affect the treatment’s ability to bind to the spike protein.
GlaxoSmithKline expects to see results from testing the drug against the full mutated spike protein in the next 2 to 3 weeks, the Journal reported.
Sotrovimab has been authorized in about a dozen countries, including the United States, which paid about $1 billion for hundreds of thousands of doses.
Other companies have also been testing their antibody treatments against the Omicron variant.
Regeneron announced Nov. 30 that its drug could be less effective, and it said further analyses will determine how much less effective by using the actual Omicron genetic sequence, according to Reuters.
Outside scientists have also said the antibody drug from Eli Lilly & Co. isn’t as effective against Omicron. The company told Reuters that it is still testing the treatment against the variant.
Another experimental antibody therapy developed by Adagio Therapeutics appears to work well against the new variant, the Journal reported, but the treatment is in late-stage clinical trials and isn’t yet authorized.
Antiviral drugs could also help prevent hospitalization and may be less vulnerable to new variants because they target a different part of the virus, the newspaper reported. Merck and Pfizer have developed antiviral pills, which still require FDA approval.
In addition, Gilead believes its approved IV therapy, called remdesivir, will continue to be effective against the variant, Reuters reported.
The FDA said Nov. 30 that it is looking at the effect that authorized COVID-19 vaccines can have on Omicron and expects to have more information in coming weeks, Reuters reported.
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