The ChAdOx1 vectored vaccine, AZD2816, induces strong immunogenicity against SARS-CoV-2 B.1.351 and other variants of concern in preclinical studies.

Spencer, A. J.; Morris, S.; Ulaszewska, M.; Powers, C.; Kaliath, R.; Bissett, C. D.; Truby, A.; Thakur, N.; Newman, J.; Allen, E. R.; Lui, C.; Dejnirattisai, W.; Mongkolsapaya, J.; Davies, H.; Donnellan, F. R.; Pulido, D.; Peacock, T. P.; Barclay, W. S.; Bright, H.; Ren, K.; Screaton, G.; McTammy, P.; Bailey, D.; Gilbert, S. C.; Lambe, T.

doi:10.1101/2021.06.08.447308

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bioRxiv · 10.1101/2021.06.08.447308

The ChAdOx1 vectored vaccine, AZD2816, induces strong immunogenicity against SARS-CoV-2 B.1.351 and other variants of concern in preclinical studies.

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Abstract

There is an ongoing global effort to design, manufacture, and clinically assess vaccines against SARS-CoV-2. Over the course of the ongoing pandemic a number of new SARS-CoV-2 virus isolates or variants of concern (VoC) have been identified containing mutations in key proteins. In this study we describe the generation and preclinical assessment of a ChAdOx1-vectored vaccine (AZD2816) which expresses the spike protein of the Beta VoC (B.1.351). We demonstrate that AZD2816 is immunogenic after a single dose. When AZD2816 is used as a booster dose in animals primed with a vaccine encoding the original spike protein (ChAdOx1 nCoV-19/ [AZD1222]), high titre binding and neutralising antibodies against Beta (B.1.351), Gamma (P.1) and Delta (B.1.617.2) are induced. In addition, a strong and polyfunctional T cell response was measured in these booster regimens. These data support the ongoing clinical development and testing of this new variant vaccine.

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Spencer, A. J., Morris, S., Ulaszewska, M., Powers, C., Kaliath, R., Bissett, C. D., Truby, A., Thakur, N., Newman, J., Allen, E. R., Lui, C., Dejnirattisai, W., Mongkolsapaya, J., Davies, H., Donnellan, F. R., Pulido, D., Peacock, T. P., Barclay, W. S., Bright, H., Ren, K., Screaton, G., McTammy, P., Bailey, D., Gilbert, S. C., Lambe, T.. 2021-06-09. The ChAdOx1 vectored vaccine, AZD2816, induces strong immunogenicity against SARS-CoV-2 B.1.351 and other variants of concern in preclinical studies.. https://doi.org/10.1101/2021.06.08.447308

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