Detailed results from the Provent Phase III pre-exposure prevention trial showed that AstraZeneca’s Evusheld (tixagevimab and cilgavimab), reduced the risk of developing symptomatic Covid-19 by 77% in the primary analysis and by 83% in the six-month follow-up analysis, compared to placebo. There were no cases of severe disease or Covid-19 related deaths in the Evusheld group through the six-month follow-up.

More than 75% of Provent participants at baseline had comorbidities that put them at high risk for severe Covid-19 if they were to become infected, including people who are immunocompromised and may have an inadequate immune response to vaccination.

Additional pharmacokinetic data showed that Evusheld concentrations remained elevated in serum for six months after administration, supporting that a single dose could provide long-term protection against COVID-19 lasting at least six months.

The data were published online today in the New England Journal of Medicine. 

Myron J. Levin, MD, Professor of Pediatrics and Medicine, University of Colorado School of Medicine, US, and PROVENT principal investigator on the trial, said: “While Covid-19 vaccines have been highly effective at reducing hospitalisation and death, cases continue to surge and many individuals remain at high risk, including immunocompromised individuals and those who cannot be vaccinated. These important data now published in the New England Journal of Medicine provide confidence that one easily administered intramuscular dose of Evusheld could provide vulnerable populations long-lasting protection. In addition, Evusheld has been shown to neutralise BA.2, currently the dominant circulating COVID-19 variant.”

Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said: "These data add to the growing body of evidence supporting the use of Evusheld to help prevent symptomatic and severe Covid-19, especially for those individuals who can’t respond adequately to vaccination and need additional protection. Evusheld is now available in many countries around the world, and we are progressing filings in pre-exposure prophylaxis as well as mild-to-moderate treatment.”

Compared to the primary analysis, the extended follow-up analysis demonstrated a greater reduction in COVID-19 incidence in the Evusheld group, with an 83% relative risk reduction (95% CI 66, 91) with Evusheld compared to placebo at a median follow up of 196 days. Symptomatic Covid-19 occurred in 11/3441 (0.3%) and 31/1731 (1.8%) participants in the Evusheld and placebo groups, respectively generally consistent across participant subgroups, where evaluable.

The six-month follow-up analysis showed no cases of severe/critical Covid-19, Covid-19-related deaths or hospitalisations in the Evusheld group; there were five cases of severe/critical disease, seven hospitalisations and two COVID-19-related deaths in the placebo group.

Approximately 2% of the global population is at increased risk of an inadequate response to Covid-19 vaccination and may benefit from pre-exposure prophylaxis with Evusheld. This population includes people who are immunocompromised, such as those with cancer or transplant patients or anyone taking immunosuppressive medicines. People at increased risk of exposure to the SARS-CoV-2 virus could also benefit from protection with Evusheld.