Impact of SARS-CoV-2 omicron and delta sub-lineage AY.4.2 variant on neutralization by sera of patients treated with different licensed monoclonal antibodies

Among the different SARS-CoV-2 variants of concern (VOCs) [1], delta and omicron currently account for the vast majority of cases worldwide, with the latter rapidly replacing the former in many countries [2]. Notably, omicron is the most divergent from the wild type B.1 strain, with 15 amino acid changes in the receptor-binding domain of the spike protein, the major target of neutralizing antibodies. Indeed, omicron partly escapes natural or vaccine-elicited immunity [3] and can decrease the efficacy of currently licensed therapeutic monoclonal antibodies (mAbs) [4, 5].