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Our partners AstraZeneca have today announced the high-level results from the primary analysis of their Phase III trial of the ChAdOx1 nCoV-19 coronavirus vaccine in the US. They confirm that the vaccine efficacy is consistent with the interim analysis results announced on Monday 22 March 2021.

Example vaccine vial in clinic © John Cairns
  • Primary analysis, part of pre-specified trial protocol, follows interim analysis on Monday 22 March
  • Data are consistent with interim analysis, and will form submission by AstraZeneca to US FDA
  • Vaccine 76% effective against symptomatic COVID-19, and 100% effective against severe or critical disease and hospitalisation

This primary efficacy analysis included the accrual of 190 symptomatic cases of COVID-19 from the 32,449 trial participants, an additional 49 cases to the previously announced interim analysis.

In addition, results were comparable across age groups, with vaccine efficacy of 85% in adults 65 years and older. A key secondary endpoint, preventing severe or critical disease and hospitalisation, demonstrated 100% efficacy.

Read the full story on the University of Oxford website.

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