MISSISSAUGA, Ontario – AstraZeneca Canada has signed an agreement with the Government of Canada for the supply of 100,000 doses of Evusheld (tixagevimab co-packaged with cilgavimab), its long-acting antibody (LAAB) combination for the prevention (pre-exposure prophylaxis) of COVID-19 in those patient populations who require additional protection.
Doses will be delivered in 2022, should Evusheld (the proposed trade name for AZD7442), receive regulatory approval from Health Canada.
In November 2021, AstraZeneca Canada announced it had initiated a rolling review New Drug Submission with Health Canada for the authorization of Evusheld. If granted, Evusheld would be the first LAAB combination to receive Health Canada authorization for COVID-19 prevention.
"Thousands of Canadians remain at serious risk for COVID-19 because they are unable to mount an adequate response to a vaccine due to an underlying health condition or medication they take that compromises their immune system," said Kiersten Combs, President of AstraZeneca Canada. "We are proud to play a leading role in fighting the COVID-19 pandemic and, with Evusheld, we now have an easily-administered, long-lasting option, which we hope will soon be available to offer protection to immune-compromised populations against COVID-19 in Canada."
Approximately 2% of the global population is considered at increased risk of an inadequate response to a COVID-19 vaccine.1,2 Additionally, more than 40% of those hospitalized with breakthrough COVID-19 infections after vaccination are immune-compromised.3,4 This includes people with blood cancers or other cancers being treated with chemotherapy, and those taking medications after an organ transplant or who are taking immunosuppressive drugs for conditions, including multiple sclerosis and rheumatoid arthritis.5-9 Emerging evidence indicates that protecting vulnerable populations from getting COVID-19 could help prevent viral evolution that is an important factor in the emergence of variants.10
In August 2021, AstraZeneca announced high-level results of the primary analysis from the PROVENT pre-exposure prophylaxis trial, which showed Evusheld 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 need 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. Further data of the ongoing PROVENT trial announced in November 2021 demonstrated the long-term benefits with an 83% reduction in the risk of developing symptomatic COVID-19 compared to placebo at a median of 6 months follow-up.
Multiple independent pseudovirus and authentic 'live' virus studies show that Evusheld retains neutralizing activity against the Omicron variant and all other tested variants of concern to date.
About Evusheld
Evusheld is a combination of two LAABs — tixagevimab (AZD8895) and cilgavimab (AZD1061) — derived from B-cells donated by convalescent patients after SARS-CoV-2 infection. 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 protein11 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;12-15 data from the Phase III PROVENT trial show protection lasting at least six months, with the Phase I trial showing high monoclonal antibody titers for at least nine months.16 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.17
In December 2021, the U.S. Food and Drug Administration issued an Emergency Use Authorization (EUA) for the use of Evusheld (tixagevimab co-packaged with cilgavimab) for the pre-exposure prophylaxis (prevention) of COVID-19. It is the only antibody authorized in the US to prevent COVID-19 symptoms before virus exposure. Evusheld is also authorized for emergency use for prevention of COVID-19 and being supplied in several other countries around the world.
In preclinical experiments, data show the LAABs were able to block the binding of the SARS-CoV-2 virus to host cells and protect against infection in cell and animal models of disease.18
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SOURCE: AstraZeneca Canada Inc.
CONTACT: Carlo Mastrangelo, AstraZeneca Canada, E-mail: carlo.mastrangelo@astrazeneca.
