Astra Vaccine Shown to Maintain Effect Against U.K. Variant
(Bloomberg) -- AstraZeneca Plc’s Covid vaccine is about as effective against the new strain of the virus that emerged in the U.K. as against the initial version, according to a study by the shot’s co-developer, the University of Oxford.
Protection against symptomatic infection was comparable for the new variant as well as the earlier strain, according to the study, which analyzed swabs taken from volunteers from October through mid-January. The findings are disclosed in a preprint version of the study that wasn’t peer-reviewed.
The results should ease concerns about the effectiveness of existing vaccines against that particular mutant form of the virus, which health officials have said may be more infectious than the initial one. Other vaccine makers have said their shots appear to be effective against the strain identified in the U.K. -- though they’ve cautioned that booster shots or next-generation vaccines may eventually be needed as the virus evolves.
There are indications that other coronavirus variants linked to Brazil and South Africa may be more problematic for vaccines. A team of researchers should soon have data from South Africa to show how well the vaccine works there, Andrew Pollard, chief investigator of the Oxford Covid vaccine trials, said Friday in a briefing.
“We’re not going to be surprised to see reduced efficacy” against the South African variant, said Mene Pangalos, Astra’s executive vice president for biopharmaceutical research. “It’s to be expected that there will be reduced activity.”
AstraZeneca fell 1.5% in London.
BioNTech SE, developer of another coronavirus vaccine with Pfizer Inc., has also said its shot appears to maintain effectiveness against the new U.K. strain.
The AstraZeneca vaccine showed 75% effectiveness against the U.K. variant, compared with 84% for other lineages of the virus, according to the study. Virus neutralization activity by vaccine-induced antibodies was much lower for those with the new strain, however.
“This suggests either that only very low levels of neutralizing activity is needed for efficacy -- as seen with Pfizer-BioNTech’s vaccine after one dose -- or that other immune mechanisms are important, or both,” said Sam Fazeli, Bloomberg Intelligence analyst, in a note.
A large U.S. study of the AstraZeneca shot will also include data on virus variants, as well as showing more definitively how well the vaccine works in people age 65 and over, Pangalos said. Results from that study are due in the next four to six weeks, he said.
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