Evasion of neutralizing antibodies by Omicron sublineage BA.2.75

Sheward, D. J.; Kim, C.; Fischbach, J.; Muschiol, S.; Ehling, R. A.; Björkström, N. K.; Karlsson Hedestam, G. B.; Reddy, S. T.; Albert, J.; Peacock, T. P.; Murrell, B.

doi:10.1101/2022.07.19.500716

bioRxiv · 10.1101/2022.07.19.500716

Evasion of neutralizing antibodies by Omicron sublineage BA.2.75

Sheward, D. J.·Kim, C.·Fischbach, J.·Muschiol, S.·Ehling, R. A.·Björkström, N. K.·Karlsson Hedestam, G. B.·Reddy, S. T.·Albert, J.·Peacock, T. P.·Murrell, B.

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Abstract

An emerging SARS-CoV-2 Omicron sublineage, BA.2.75, is increasing in frequency in India and has been detected in at least 15 countries as of 19 July 2022. Relative to BA.2, BA.2.75 carries nine additional mutations in spike. Here we report the sensitivity of the BA.2.75 spike to neutralization by a panel of clinically-relevant and pre-clinical monoclonal antibodies, as well as by serum from blood donated in Stockholm, Sweden, before and after the BA.1/BA.2 infection wave. BA.2.75 largely maintains sensitivity to bebtelovimab, despite a slight reduction in potency, and exhibits moderate susceptibility to tixagevimab and cilgavimab. For sera sampled both before and after the BA.1/BA.2 infection wave, BA.2.75 does not show significantly greater antibody evasion than the currently-dominating BA.5.

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Sheward, D. J., Kim, C., Fischbach, J., Muschiol, S., Ehling, R. A., Björkström, N. K., Karlsson Hedestam, G. B., Reddy, S. T., Albert, J., Peacock, T. P., Murrell, B.. 2022-07-20. Evasion of neutralizing antibodies by Omicron sublineage BA.2.75. https://doi.org/10.1101/2022.07.19.500716

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