AstraZeneca sells another half-million doses of its COVID-19 antibody combo to the US

Order up. Shortly after topping off supplies of COVID-19 drugs from Pfizer and GlaxoSmithKline, the U.S. has asked for a second helping of AstraZeneca’s antibody combo.

The government has purchased an additional 500,000 doses of AZ’s long-acting antibody cocktail Evusheld, or tixagevimab plus cilgavimab. That comes on top of 700,000 doses the U.S. already ordered, for a total supply of 1.2 million, the British drugmaker said Wednesday. AstraZeneca plans to complete the entire delivery within the first quarter of 2022.

Unlike the COVID-19 antibody drugs from Eli Lilly, Regeneron and GlaxoSmithKline-Vir Biotechnology, AstraZeneca’s therapeutic is authorized for prevention before exposure to the virus. Specifically, the FDA in December authorized Evusheld in people with moderately to severely compromised immune systems, either from a medical condition or the use of immunosuppressive medications. People with a history of severe reactions to COVID-19 vaccines are also eligible to receive the therapeutic.

“Today’s agreement will bring protection to some of the most vulnerable people in the US, including the immunocompromised, who may receive limited or no protection from vaccines and currently have few options in the face of the rapid rise in COVID-19 cases seen in recent weeks,” Iskra Reic, executive vice president of vaccines and immune therapies at AZ, said in a statement.

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AstraZeneca didn’t say how much the U.S. would pay for the extra half-million doses. The company noted “additional details” on the agreement will emerge in the "coming weeks.”

Aside from its preexposure prophylactic distinction, Evusheld is one of just two authorized antibody therapies to show neutralizing activity against omicron and “all other variants,” according to AZ. AstraZeneca credits that efficacy, demonstrated in recent live and pseudovirus studies, to the fact that Evusheld combines two “particularly potent antibodies with different and complementary activities against the virus.” This helps the antibody cocktail evade potential resistance as new SARS-CoV-2 variants crop up, AZ said.

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So far in 2022, the U.S. had made a habit out of re-upping its stores of COVID-19 therapeutics. During the first week of January, the government doubled its order for Pfizer’s antiviral pill Paxlovid from 10 million courses to 20 million. Half of the order is up for delivery by the end of June, with the remaining 10 million courses expected to arrive by the end of September, Pfizer has said.

And Tuesday, a day before AstraZeneca announced its second Evusheld order, GlaxoSmithKline and Vir said the U.S. had locked up another 600,000 doses of their monoclonal antibody sotrovimab, which the partners aim to deliver through the first quarter. The U.S. splashed out roughly $1 billion for its initial sotrovimab order back in November.