LONDON: British pharmaceutical giant AstraZeneca said on Thursday that a third, or “booster”, dose of its Covid-19 vaccine Vaxzevria “significantly” lifted antibody levels against the Omicron strain in a laboratory study.
AstraZeneca also revealed in other findings that its preventative moniclonal antibody treatment, Evusheld, “retains neutralisation activity” against Omicron.
The threat of the highly transmissible Omicron variant looms large over the festive holidays, forcing many governments to roll out new curbs and urge citizens to get vaccinated. However, separate UK research on Thursday suggested that Omicron infections are less likely to result in hospitalisation compared to the Delta variant.
“Vaxzevria significantly boosted levels of antibodies against the Omicron SARS-CoV-2 variant (B.1.1.529) following a third dose booster,” AstraZeneca said in a statement.
“The third dose booster vaccination neutralised the Omicron variant to levels that were broadly similar to those observed… after the second dose against the Delta variant.” Levels of neutralising antibodies were also higher with the booster jab than with individuals who had previously been infected and recovered naturally.
The study was conducted by investigators from the University of Oxford, which is the academic institution which helped AstraZeneca develop the vaccine last year.
Researchers analysed blood samples taken from individuals infected with Covid-19; those vaccinated with two doses plus a booster; and those who had reported previous infection. “It is very encouraging to see that current vaccines have the potential to protect against Omicron following a third dose booster,” said University of Oxford professor John Bell, one of the study investigators.