bioRxiv. 2022 Feb 16:2022.02.15.480166. doi: 10.1101/2022.02.15.480166. Preprint.
Monoclonal antibody therapy for the treatment of SARS-CoV-2 infection has been highly successful in decreasing disease severity; however, the recent emergence of the heavily mutated Omicron variant has posed a challenge to this treatment strategy. The Omicron variant BA.1 has been found to evade neutralization by the Regeneron and Eli Lilly therapeutic monoclonal antibodies, while Sotrovimab and the Evusheld monoclonal antibody cocktail retain significant neutralizing activity. A newly emerged variant, Omicron BA.2, containing the BA.1 mutations plus an additional 6 mutations and 3 deletions, 3 of which lie in the receptor binding domain, has been found to be spreading with increased transmissibility. We report here, using a spike protein-pseudotyped lentivirus assay, that Omicron BA.2 is not neutralized with detectable titer by any of the therapeutic monoclonal antibodies, including Sotrovimab and the Evusheld monoclonal antibodies. The results demonstrate the difficulty of identifying broadly neutralizing monoclonal antibodies against SARS-CoV-2 and the importance of the T cell response from which immunoevasion is more difficult.