Positive high-level results from the TACKLE Phase III COVID-19 treatment trial have shown that AstraZeneca’s AZD7442, a long-acting antibody (LAAB) combination, achieved a statistically significant reduction in severe COVID-19 or death compared to placebo in non-hospitalised patients with mild-to-moderate symptomatic COVID-19.

On 5 October 2021, the company announced that it had submitted a request to the US Food and Drug Administration for Emergency Use Authorisation for AZD7442 for prophylaxis of COVID-19. A total of 90% of participants enrolled were from populations at high risk of progression to severe COVID-19, including those with co-morbidities.

The trial met the primary endpoint, with a dose of 600mg of AZD7442 given by intramuscular (IM) injection reducing the risk of developing severe COVID-19 or death (from any cause) by 50% compared to placebo in outpatients who had been symptomatic for seven days or less. The trial recorded 18 events in the AZD7442 arm (18/407) and 37 in the placebo arm (37/415). The LAAB was generally well-tolerated in the trial.

In a prespecified analysis of participants who received treatment within five days of symptom onset, AZD7442 reduced the risk of developing severe COVID-19 or death (from any cause) by 67% compared to placebo, with nine events in the AZD7442 arm (9/253) and 27 in the placebo arm (27/251).

AZD7442 is the first LAAB with Phase III data to demonstrate benefit in both prophylaxis and treatment of COVID-19 and is easily administered by IM injection.

Hugh Montgomery, Professor of Intensive Care Medicine at University College London, and TACKLE principal investigator said: “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. These positive results show that a convenient intramuscular dose of AZD7442 could play an important role in helping combat this devastating pandemic.”

Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, 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. Early intervention with our antibody can give a significant reduction in progression to severe disease, with continued protection for more than six months.”