New Astra-Zeneca B.1.351 vaccine AZD2816 strongly immunogenic against multiple SARS-CoV-2 variants of concern.
A new study, released on the bioRxiv* preprint server, supports the efficacy of the wildtype ChAdOx1 nCoV-19 (AZD1222) vaccine against B.1.351, B.1.617.1 and B.1.617.2, while showing that a booster dose of vaccine based on the B.1.351 spike induces further increase in antibody titers.
B.1.351 is thought to have been responsible for the second wave of infection in South Africa, with proportionally more young patients than in the first wave. This variant contains N501Y and 484K, among other mutations in the spike protein, of which three are thought to enhance spike-receptor binding affinity.
In the current experiment, the researchers found that a single dose of either the new vaccine or the original ChAdOx1 nCoV-19 (AZD1222) vaccine produced a robust antibody response. The same was the case when the booster was a mix of both vaccines.
Dr. Liji Thomas