Pfizer Inc. and its German vaccine partner said their booster tailored to the latest omicron variants raised more antibodies against the dominant strains of COVID-19 when compared with the original shot designed to fight the form of the virus.
Blood from 80 volunteers collected seven days after the booster shot showed an increase in neutralizing antibodies against the BA.4 and BA.5 subvariants in a study, Pfizer and BioNTech SE said in a statement Thursday.
The vaccines were authorized without data showing their performance in humans. Pfizer and BioNTech plan to release additional data in coming weeks measuring immune responses one month following administration of the new bivalent booster. They have not shared data on the shot’s efficacy, which would offer a better measure of protection against widely circulating variants.
