AstraZeneca COVID-19 antibodies unlikely to protect against new Omicron subvariant
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The FDA warned healthcare providers Monday that monoclonal antibodies tixagevimab and cilgavimab marketed as Evusheld by AstraZeneca (NASDAQ:AZN) for COVID-19 prophylaxis could be less active against fast-spreading Omicron subvariant BA.4.6.
Citing lab studies, the agency said that BA.4.6 indicated over a 1,000 decline in susceptibility antibody to Evusheld, which is authorized in the U.S. for the pre-exposure prevention of COVID-19 in those who are immunocompromised or for whom COVID vaccines are not recommended.
According to data from the Centers for Disease Control and Prevention (CDC), BA.4.6 made up an estimated ~13% of COVID variants in the U.S. for the week ending Oct. 01, up from only ~8% in the final week of August.
An AstraZeneca (AZN) spokesperson told Endpoints News that the FDA lab data indicated âEvusheld is unlikely to be active against BA.4.6, which currently represents 6.2% of infections globally and growing slowly; it is not exÂ­pectÂ­ed to beÂ­come a domÂ­iÂ­nant strain.â
Noting that Evusheld remains protective against the dominant BA.5 variant, the spokesperson said that the FDA-approved prophylactic âshould continue to provide protection to the vast majority of intended recipients.â
The rising prevalence of BA.4.6 can darken the prospects for Evusheld, which added $914M for the company in 1H 2022.
Reduced effectiveness against the then-dominant Omicron BA.2 sub-variant prompted the FDA to restrict the use of Sotrovimab â the COVID-19 antibody therapy developed by GlaxoSmithKline (GSK) and Vir Biotechnology (VIR).
The rival antibody therapies from Regeneron (REGN) and Eli Lilly (LLY) met the same fate after data indicated they were less effective against the original Omicron variant.