AstraZeneca says its vaccine was 79% effective at preventing any COVID-19 symptoms and 100% at preventing severe ones in large-scale U.S. trials, and also had no safety issues with blood clots.
The results of the trials involving 32,449 people, reported Monday, pave the way for the company to request emergency-use authorization in the United States. The vaccine is already being administered widely in other countries around the world, such as Britain, on the strength of testing conducted outside the U.S.
Notably, the company said the U.S. results showed the vaccine to be 80% effective in people 65 and older. Its efficacy was also consistent across ethnicities.
“These findings re-confirm previous results observed in ... trials across all adult populations, but it’s exciting to see similar efficacy results in people over 65 for the first time,” said Ann Falsey, a professor at the University of Rochester medical school in upstate New York and one of the principal investigators for the trial. “This analysis validates the AstraZeneca COVID-19 vaccine as a much-needed additional vaccination option.”