Neutralization of Omicron SARS-CoV-2 by 2 or 3 doses of BNT162b2 vaccine

Xia, H.; Zou, J.; Kurhade, C.; Cai, H.; Yang, Q.; Cutler, M.; Cooper, D.; Muik, A.; Jansen, K. U.; Xie, X.; Swanson, K. A.; Shi, P.-Y.

doi:10.1101/2022.01.21.476344

bioRxiv · 10.1101/2022.01.21.476344

Neutralization of Omicron SARS-CoV-2 by 2 or 3 doses of BNT162b2 vaccine

Xia, H.·Zou, J.·Kurhade, C.·Cai, H.·Yang, Q.·Cutler, M.·Cooper, D.·Muik, A.·Jansen, K. U.·Xie, X.·Swanson, K. A.·Shi, P.-Y.

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Abstract

We report the antibody neutralization against Omicron SARS-CoV-2 after 2 and 3 doses of BNT162b2 mRNA vaccine. Vaccinated individuals were serially tested for their neutralization against wild-type SARS-CoV-2 (strain USA-WA1/2020) and an engineered USA-WA1/2020 bearing the Omicron spike glycoprotein. Plaque reduction neutralization results showed that at 2 or 4 weeks post-dose-2, the neutralization geometric mean titers (GMTs) were 511 and 20 against the wild-type and Omicron-spike viruses, respectively, suggesting that two doses of BNT162b2 were not sufficient to elicit robust neutralization against Omicron; at 1 month post-dose-3, the neutralization GMTs increased to 1342 and 336, respectively, indicating that three doses of vaccine increased the magnitude and breadth of neutralization against Omicron; at 4 months post-dose-3, the neutralization GMTs decreased to 820 and 171, respectively, suggesting similar neutralization decay kinetics for both variants. The data support a three-dose vaccine strategy and provide the first glimpse of the neutralization durability against Omicron.

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Xia, H., Zou, J., Kurhade, C., Cai, H., Yang, Q., Cutler, M., Cooper, D., Muik, A., Jansen, K. U., Xie, X., Swanson, K. A., Shi, P.-Y.. 2022-01-22. Neutralization of Omicron SARS-CoV-2 by 2 or 3 doses of BNT162b2 vaccine. https://doi.org/10.1101/2022.01.21.476344

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