Neutralization against Omicron BA.1
VIRUS
Thirty-five patients were found be seronegative after the third dose. Due to the emergence of the Omicron BA.1 wave, we further assessed neutralization activity for the seronegative cohort (N=35) against WT SARS-CoV-2 and BA1.1.529 (Omicron BA.1). At 4 weeks (after third dose) neutralization was noted in 46% patients (16/35) for the WT virus while only 17% of patients had detectable neutralization activity (6/35) for the Omicron variant. These results are summarized in 