AstraZeneca's antibody cocktail Evusheld works against Omicron in USFDA study

Drug firm AstraZeneca noted on Friday that new preclinical data has shown that its COVID-19 antibody cocktail 'Evusheld' retained neutralising activity against the Omicron variant of the coronavirus.

In this preclinical study, Evusheld's Inhibitory Concentration 50 (IC50), a measure of neutralising potency of an antibody, was 171 ng/ml and 277 ng/ml in two confirmatory tests, which is within the range of neutralising titres found in someone who has been previously infected with COVID-19.

The study was done independently by investigators at the US Food and Drug Administration (USFDA), Center for Biologics Evaluation and Research. The work was supported by US government research funds.

The early data, generated by pseudovirus testing of the full Omicron variant spike against the combination of tixagevimab with cilgavimab, the antibodies that comprise Evusheld, add to the growing body of preclinical evidence demonstrating that Evusheld retains activity against all tested variants of concern to date.

Commenting in the discovery, Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said: "This study shows Evusheld retains neutralisation activity against the Omicron variant. By combining two potent antibodies with different and complementary activities against the virus, Evusheld was designed to evade potential resistance with the emergence of new SARS-CoV-2 variants."

"Evusheld is the first long-acting antibody to receive emergency use authorisation in the US for pre-exposure prophylaxis of COVID-19, in addition to authorisations in other countries, and we are working with regulators on applications for the use of Evusheld in treating COVID-19," Pangalos added.

The Omicron variant was not in circulation during the Evusheld clinical trials.

Evusheld had received Emergency Use Authorization (EUA) in the US in December 2021 for prevention of COVID-19 in people with moderate to severe immune compromise due to a medical condition or immunosuppressive medications. The first doses are expected to become available soon.

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