The U.S. health regulator said on April 5 GlaxoSmithKline and Vir Biotechnology’s antibody therapy was no longer authorized as a COVID-19 treatment, with data suggesting it was unlikely to be effective against the dominant Omicron sub-variant in the country.

The U.S. health regulator said on March 25 the current authorized dose of GlaxoSmithKline and Vir Biotechnology’s COVID-19 antibody therapy is unlikely to be effective against the Omicron BA.2 variant.

The BA.2 subvariant of Omicron, which appears to be even more transmissible than Omicron, is accounting for more than a third of global COVID-19 cases. In other news, the U.S. Food and Drug Administration placed limits on the use of GlaxoSmithKline and Vir Biotechnology’s COVID-19 antibody therapeutic, sotrovimab.

The U.S. Food and Drug Administration said on February 23 GlaxoSmithKline and Vir Biotech’s COVID-19 antibody treatment should not be used in places with circulation of variants that are not susceptible to the drug.

An antibody-based COVID-19 therapy developed by GSK and Vir Biotechnology retains neutralizing activity against the emerging BA.2 form of the Omicron coronavirus variant, according to data from a laboratory study cited by Vir on February 10.

GlaxoSmithKline and U.S. partner Vir Biotechnology will boost production of their antibody-based COVID-19 treatment by adding a second manufacturing plant to help meet soaring demand in the United States.

GlaxoSmithKline and Vir Biotechnology said final results from a late-stage study of their monoclonal antibody confirmed sotrovimab significantly reduced hospitalization and death among high-risk Covid-19 patients when given early in the disease.