mRNA-1273 and Ad26.COV2.S vaccines protect against the B.1.621 variant of SARS-CoV-2

Darling, T. L.; Ying, B.; Whitener, B.; VanBlargan, L.; Bricker, T. L.; Liang, C.-Y.; Joshi, A.; Bamunuarachchi, G.; Seehra, K.; Schmitz, A.; Halfmann, P.; Kawaoka, Y.; Elbashir, S.; Edwards, D. K.; Thackray, L.; Diamond, M.; Boon, A.

doi:10.1101/2021.12.29.474432

bioRxiv · 10.1101/2021.12.29.474432

mRNA-1273 and Ad26.COV2.S vaccines protect against the B.1.621 variant of SARS-CoV-2

Darling, T. L.·Ying, B.·Whitener, B.·VanBlargan, L.·Bricker, T. L.·Liang, C.-Y.·Joshi, A.·Bamunuarachchi, G.·Seehra, K.·Schmitz, A.·Halfmann, P.·Kawaoka, Y.·Elbashir, S.·Edwards, D. K.·Thackray, L.·Diamond, M.·Boon, A.

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Abstract

Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019, viral variants with greater transmissibility or immune evasion properties have arisen, which could jeopardize recently deployed vaccine and antibody-based countermeasures. Here, we evaluated in mice and hamsters the efficacy of preclinical non-GMP Moderna mRNA vaccine (mRNA-1273) and the Johnson & Johnson recombinant adenoviral-vectored vaccine (Ad26.COV2.S) against the B.1.621 (Mu) South American variant of SARS-CoV-2, which contains spike mutations T95I, Y144S, Y145N, R346K, E484K, N501Y, D614G, P681H, and D950N. Immunization of 129S2 and K18-human ACE2 transgenic mice with mRNA-1273 vaccine protected against weight loss, lung infection, and lung pathology after challenge with B.1.621 or WA1/2020 N501Y/D614G SARS-CoV-2 strain. Similarly, immunization of 129S2 mice and Syrian hamsters with a high dose of Ad26.COV2.S reduced lung infection after B.1.621 virus challenge. Thus, immunity induced by mRNA-1273 or Ad26.COV2.S vaccines can protect against the B.1.621 variant of SARS-CoV-2 in multiple animal models.

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Darling, T. L., Ying, B., Whitener, B., VanBlargan, L., Bricker, T. L., Liang, C.-Y., Joshi, A., Bamunuarachchi, G., Seehra, K., Schmitz, A., Halfmann, P., Kawaoka, Y., Elbashir, S., Edwards, D. K., Thackray, L., Diamond, M., Boon, A.. 2021-12-29. mRNA-1273 and Ad26.COV2.S vaccines protect against the B.1.621 variant of SARS-CoV-2. https://doi.org/10.1101/2021.12.29.474432

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