|Articles|October 11, 2021

AstraZeneca’s Long-Acting Antibody AZD7442 Reduced Risk of Severe or Fatal COVID-19

Author(s)Nina Cosdon

In the recent TACKLE phase 3 trial, AZD7442 significantly reduced the risk of developing severe COVID-19 or death, even among high-risk populations.

AstraZeneca's AZD7442 long-acting antibody (LAAB) combination achieved a significant reduction in severe COVID-19 or death, according to a statement released today.

Upon receipt of positive high-level results from the TACKLE phase 3 COVID-19 treatment trial, AstraZeneca declared AZD7442 to be the only LAAB combination for COVID-19 prophylaxis and treatment.

Mene Pangalos, Executive Vice President of BioPharmaceuticals R&D at AstraZeneca, said, “These important results for AZD7442, our long-acting antibody combination, add to the growing body of evidence for use of this therapy in both prevention and treatment of COVID-19. An early intervention with our antibody can give a significant reduction in progression to severe disease, with continued protection for more than six months.”

At the trial’s primary endpoint, AZD7442 reduced the risk of severe COVID-19 or death (from any cause) by 50% as compared to the placebo. During this randomized, double-blind, placebo-controlled, multicenter trial, participants were given one 600 mg dose of AZD7442 via intramuscular injection.

Trial participants were 903 outpatients who had been symptomatic for seven days or fewer. Notably, 90% of participants enrolled in the TACKLE phase 3 trial were at high-risk of developing severe COVID-19, including those with comorbidities. The study recorded 18 events in the AZD7442 arm (18/407) and 37 in the placebo arm (37/415).

In an analysis of outpatients who received treatment within five days of symptoms, AZD7442 reduced the risk of severe or fatal COVID-19 by 67% as compared to the placebo, with nine events in the AZD7442 arm (9/253) and 27 in the placebo arm (27/251).

AZD7442 is a combination of tixagevimab (AZD8895) and cilgavimab (AZD1061), derived from B-cells donated by patients who recovered from COVID-19. AstraZeneca reported that AZD7442 was generally well-tolerated.

AstraZeneca had previously filed an Emergency Use Authorization (EUA) for AZD7442, citing the devastation caused by the COVID-19 pandemic. According to Hugh Montgomery, Professor of Intensive Care Medicine at University College London and the TACKLE principal investigator, “With continued cases of serious COVID-19 infections across the globe, there is a significant need for new therapies like AZD7442 that can be used to protect vulnerable populations from getting COVID-19 and can also help prevent progression to severe disease.”


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