Serum Neutralizing Activity of mRNA-1273 against SARS-CoV-2 Variants

Choi, A.; Koch, M.; Wu, K.; Dixon, G.; Oestreicher, J.; Legault, H.; Stewart-Jones, G. B. E.; Colpitts, T.; Pajon, R.; Bennett, H.; Carfi, A.; Edwards, D. K.

doi:10.1101/2021.06.28.449914

bioRxiv · 10.1101/2021.06.28.449914

Serum Neutralizing Activity of mRNA-1273 against SARS-CoV-2 Variants

Choi, A.·Koch, M.·Wu, K.·Dixon, G.·Oestreicher, J.·Legault, H.·Stewart-Jones, G. B. E.·Colpitts, T.·Pajon, R.·Bennett, H.·Carfi, A.·Edwards, D. K.

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Abstract

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has led to growing concerns over increased transmissibility and the ability of some variants to partially escape immunity. Sera from participants immunized on a prime-boost schedule with the mRNA-1273 COVID-19 vaccine were tested for neutralizing activity against several SARS-CoV-2 variants, including variants of concern (VOCs) and variants of interest (VOIs), compared to neutralization of the wild-type SARS-CoV-2 virus (designated as D614G). Results showed minimal effects on neutralization titers against the B.1.1.7 (Alpha) variant (1.2-fold reduction compared with D614G); other VOCs such as B.1.351 (Beta, including B.1.351-v1, B.1.351-v2, and B.1.351-v3), B.1.617.2 (Delta), and P.1 (Gamma) showed decreased neutralization titers ranging from 2.1-fold to 8.4-fold reductions compared with D614G, although all remained susceptible to mRNA-1273-elicited serum neutralization.

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Choi, A., Koch, M., Wu, K., Dixon, G., Oestreicher, J., Legault, H., Stewart-Jones, G. B. E., Colpitts, T., Pajon, R., Bennett, H., Carfi, A., Edwards, D. K.. 2021-06-28. Serum Neutralizing Activity of mRNA-1273 against SARS-CoV-2 Variants. https://doi.org/10.1101/2021.06.28.449914

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