AZD7442 is the first antibody combination (non-vaccine) modified to potentially provide long-lasting protection that has demonstrated prevention of COVID-19 in a clinical trial. It is a combination of two LAABs – tixagevimab (AZD8895) and cilgavimab (AZD1061) – derived from B-cells donated by convalescent patients after SARS-CoV-2 virus.
The antibody combination could help provide extra protection to high risk people who are unable to be vaccinated or have an inadequate response to vaccination.
In June, AstraZeneca announced that a parallel Phase 3 Storm Chaser trial for AZD7442 did not meet the primary endpoint of post-exposure prevention of COVID-19. But today it revealed that the Phase 3 Provent pre-exposure trial achieved a statistically significant reduction in the incidence of symptomatic COVID-19, thus meeting this trial’s primary endpoint.
AstraZeneca is now preparing regulatory submission of the prophylaxis data to health authorities for potential emergency use authorisation or conditional approval.
‘This could be an important tool in our arsenal to help people who may need more than a vaccine’
AZD7442 was discovered by Vanderbilt University Medical Center and licensed to AstraZeneca in June 2020. The human monoclonal antibodies bind to distinct sites on the SARS-CoV-2 spike protein; and have been optimised by AstraZeneca with half-life extension and reduced Fc receptor and complement C1q binding.
This half-life extension more than triples the durability of its action compared to conventional antibodies and could afford up to 12 months of protection from COVID-19 following a single administration, according to AstraZeneca. Preliminary in vitro findings suggest AZD7442 neutralises virus variants, including Delta.