AstraZeneca said Friday it plans to apply for regulatory approval of an antibody cocktail that a preliminary study showed was highly effective in preventing symptomatic COVID-19, offering a potential alternative or complement to vaccines.
The Anglo-Swedish drugmaker announced in an Aug. 20 release that the drug, a combination of two long-acting antibodies derived from convalescent plasma, reduced the risk of symptomatic COVID-19 by 77 percent in a clinical trial.
The antibody cocktail, called AZD7442, was evaluated in a randomized, double-blind, placebo-controlled trial involving over 5,000 across multiple countries, including the United States. While the study has not yet been peer-reviewed, AstraZeneca said full results would be submitted for publication in a peer-reviewed medical journal.
None of the trial participants who received AstraZeneca’s drug, administered as a single shot via intramuscular injection, developed severe COVID-19 or died from the disease, according to the release. There were three cases of severe illness and two deaths among those who received a placebo.
AstraZeneca said that over three quarters of the participants had comorbidities that included conditions associated with reduced immune response to COVID-19 vaccines, with encouraging implications for people for whom vaccines provide limited protection.
“With these exciting results, AZD7442 could be an important tool in our arsenal to help people who may need more than a vaccine to return to their normal lives,” Dr. Myron J. Levin, a professor at the University of Colorado School of Medicine and the principal investigator on the trial, said in a statement.
While AstraZeneca’s release cast the product as a complement to vaccines, rather than an alternative, people who refuse to get one of the several COVID-19 vaccines currently available under emergency use authorization are also likely to find the development encouraging.
“We need additional approaches for individuals who are not adequately protected by COVID-19 vaccines,” AstraZeneca executive Mene Pangalos said in a statement. “We are very encouraged by these efficacy and safety data in high-risk people, showing our long-acting antibody combination has the potential to protect from symptomatic and severe disease, alongside vaccines.”
AZD7442 is a combination of two antibodies—tixagevimab and cilgavimab—which were derived from B-cells donated by patients who recovered from COVID-19.
By optimizing the human monoclonal antibodies, AstraZeneca extended their longevity, more than tripling the durability of their effectiveness. This means a single shot could provide up to 12 months protection from COVID-19, the company said.
Further, preliminary “in vitro” findings from investigators at Oxford University and Columbia University showed that AstraZeneca’s antibody cocktail was effective at neutralizing other variants of COVID-19, including the more contagious Delta.