AstraZeneca has submitted a request to the US FDA for an emergency use authorization (EUA) for AZD7442, its long-acting antibody (LAAB) combination, for prophylaxis of symptomatic COVID-19.
If granted, AZD7442 would be the first LAAB to receive an EUA for COVID-19 prevention. It is the first LAAB with Phase III data demonstrating a statistically significant reduction in the risk of developing symptomatic COVID-19 compared to placebo.
AZD7442 is a combination of two LAABs — tixagevimab (AZD8895) and cilgavimab (AZD1061) — derived from B-cells donated by convalescent patients after SARS-CoV-2 virus.
In August 2021, AstraZeneca announced high-level results from the PROVENT pre-exposure prophylaxis trial which showed AZD7442 reduced the risk of developing symptomatic COVID-19 by 77% (95% confidence interval (CI): 46, 90), compared to placebo. Importantly, the trial population included people with co-morbidities and who may be in need of additional protection from SARS-CoV-2 infection. Greater than 75% of participants in PROVENT presented with co-morbidities associated with an increased risk of severe disease or a reduced immune response to vaccination. The trial accrued 25 cases of symptomatic COVID-19 at the primary analysis. AZD7442 was well-tolerated.
The EUA request filing includes safety and efficacy data from the PROVENT and STORM CHASER Phase III trials and the Phase I trial. AZD7442 was optimized using AstraZeneca’s proprietary YTE half-life extension technology which more than triples the durability of its action compared to conventional antibodies.1-4 Preliminary ‘in vitro’ findings demonstrate that AZD7442 demonstrates broad anti-COVID activity, and in particular neutralizes recent emergent SARS-CoV-2 viral variants, including the Delta and Mu variants.5,6
Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said: “Vulnerable populations such as the immunocompromised often aren’t able to mount a protective response following vaccination and continue to be at risk of developing COVID-19. With this first global regulatory filing, we are one step closer to providing an additional option to help protect against COVID-19 alongside vaccines. We look forward to sharing AZD7442 data for the treatment of COVID-19 later this year.”
AZD7442 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 human monoclonal antibodies bind to distinct sites on the SARS-CoV-2 spike protein7 and were optimized by AstraZeneca with half-life extension and reduced Fc receptor and complement C1q binding. The 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;1-4 data from the Phase I trial show high neutralizing antibody titres for at least nine months.8 The reduced Fc receptor binding aims to minimize the risk of antibody-dependent enhancement of disease – a phenomenon in which virus-specific antibodies promote, rather than inhibit, infection and/or disease.9