AstraZeneca, Regeneron Confident Their COVID-19 Antibody Cocktails Are Effective Against Omicron

Regeneron and AstraZeneca said their therapeutic antibody cocktails remain active against Omicron, but questions remain in light of a Chinese study concluding that the variant escapes 85 percent of tested antibodies.

AstraZeneca posted laboratory results showing that its Evusheld (tixagevimab and cilgavimab) retained neutralization power similar to that found in a person previously infected with COVID-19. The study was performed independently by the FDA’s Center for Biologics Evaluation and Research, the company noted.

Regeneron did not provide detailed data, saying “Currently authorized REGEN-COV (casirivimab and imdevimab) antibodies have diminished potency vs. Omicron but are active against the predominant Delta variant.” However, the company said the combo “maintained an adequate potency when tested on Omicron samples,” according to new preclinical data.

Both companies cited the “Open Data Portal SARS-CoV-2 Variants and Therapeutics Activity Explorer,” hosted by the National Center for Advancing Translational Science. The website contains detailed data on COVID-19 vaccines, antibodies and therapeutics and their potency against all 15 variants of the SARS-CoV-2 virus.