LONDON – The vaccine developed by the University of Oxford and AstraZeneca PLC is effective against a highly transmissible new variant of the virus that causes Covid-19, according to an analysis that provides further assurance that a global vaccination drive will help stem the pandemic to end. .
Still, the small study showed that the vaccine works better against older, more established versions of the virus, which to date has been linked to nearly 2.3 million deaths worldwide and more than 100 million cases.
In a study published online Friday, researchers examined blood samples from about 256 participants in an ongoing clinical trial of the vaccine who tested positive for Covid-19. The findings are preliminary and have not been formally reviewed by other scientists.
Genetic sequencing allowed them to identify which participants were infected with the new variant and who had an older version. Slightly less than a third had the new variant.
The British Coronavirus variant
By testing antibody levels and other markers of immune system activity against the virus, the researchers found that the vaccine elicited an effective immune response against the new variant in 75% of the cases that showed symptoms of infection, and in about two-thirds of the cases as those who did not. symptoms were also included.
For those with the older strain, the vaccine was effective in 84% of symptomatic cases and 81% of all cases.
The researchers reported widely different antibody responses between the two groups, saying that antibodies induced by the vaccine were up to nine times less effective in neutralizing the new variant than the old one. Overall protection was similar, suggesting other parts of the immune system play key roles, the study said.
“The vaccine’s effectiveness was maintained against the new variant,” the researchers said.
The emergence of more contagious variants of the virus has sparked new waves of infection in various parts of the world, and there is serious concern that the virus could potentially bypass vaccines that are now rolling out across much of the world.
The latest findings from Oxford and AstraZeneca add to signs that this does not seem to be the case for now. Pfizer Inc.
and Moderna Inc.
have reported that their vaccines are also effective against new variants, citing similar lab tests.
As new variants of coronavirus fly around the world, scientists are rushing to understand how dangerous they can be. WSJ explains. Illustration: Alex Kuzoian / WSJ
Write to Jason Douglas at [email protected]
Copyright © 2020 Dow Jones & Company, Inc. All rights reserved. 87990cbe856818d5eddac44c7b1cdeb8