New analyses of two AZD 7442 COVID-19 Phase III trials, PROVENT and TACKLE, in high-risk populations confirm robust efficacy and long-term prevention of COVID-19. AstraZeneca

In an analysis of the ongoing PROVENT trial evaluating a median six months of participant follow-up, one 300mg IM dose of AZD 7442 reduced the risk of developing symptomatic COVID-19 compared to placebo by 83%. About 2% of the global population is considered at increased risk of an inadequate response to a COVID-19 vaccine. This includes people with blood cancers or other cancers being treated with chemotherapy, patients on dialysis, those taking medications after an organ transplant or who are taking immunosuppressive drugs for conditions including multiple sclerosis and rheumatoid arthritis.

The AZD 7442 PROVENT trial is the first Phase III trial prospectively designed to evaluate a monoclonal antibody for pre-exposure prophylaxis of symptomatic COVID-19, with targeted inclusion of high-risk and immunocompromised participants. More than 75% of PROVENT participants at baseline had co-morbidities that put them at high risk for severe COVID-19 if they were to become infected, including people who are immunocompromised and may have a reduced immune response to vaccination.

There were no cases of severe COVID-19 or COVID-19-related deaths in those treated with AZD 7442 at either the primary or six-month analyses. In the placebo arm, there were two additional cases of severe COVID-19 at the six-month assessment, for a total of five cases of severe COVID-19 and two COVID-related deaths. An exploratory analysis of the TACKLE outpatient treatment trial, in patients with mild-to-moderate COVID-19, showed that one 600mg IM dose of AZD 7442 reduced the risk of developing severe COVID-19 or death (from any cause) by 88% compared to placebo in patients who had been symptomatic for three days or less at the time of treatment.

A total of 90% of participants enrolled in TACKLE were from populations at high risk of progression to severe COVID-19 if they became infected, including those with co-morbidities. In both PROVENT and TACKLE, AZD 7442 was generally well tolerated. No new safety issues were identified in the six-month analysis of PROVENT.

Full results from PROVENT and TACKLE will be submitted for publication in a peer-reviewed medical journal and presented at a forthcoming medical meeting. On 5 October 2021, the Company announced that it had submitted a request to the FDA for Emergency Use Authorisation for AZD 7442 for prophylaxis of COVID-19.