Impact of prior SARS-CoV-2 acquisition on binding and neutralizing antibody responses following COVID-19 vaccination: A cross-protocol analysis of individual-level data from six phase 3 clinical trials

In SARS-CoV-2-naïve individuals, a two-dose vaccine regimen is needed to provide antibody levels correlated with protection against disease caused by the cognate virus strain. In contrast, in individuals with prior SARS-CoV-2 acquisition, a single dose of any of the tested vaccines/platforms (mRNA/protein/vector) provides comparably high antibody levels.