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bioRxiv · 10.1101/2021.07.19.452771

Comparison of Neutralizing Antibody Titers Elicited by mRNA and Adenoviral Vector Vaccine against SARS-CoV-2 Variants

Tada, T.·Zhou, H.·Samanovic, M. I.·Dcosta, B. M.·Cornelius, A.·Mulligan, M. J.·Landau, N. R.
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Abstract

The increasing prevalence of SARS-CoV-2 variants has raised concerns regarding possible decreases in vaccine efficacy. Here, neutralizing antibody titers elicited by mRNA-based and an adenoviral vector-based vaccine against variant pseudotyped viruses were compared. BNT162b2 and mRNA-1273-elicited antibodies showed modest neutralization resistance against Beta, Delta, Delta plus and Lambda variants whereas Ad26.COV2.S-elicited antibodies from a significant fraction of vaccinated individuals were of low neutralizing titer (IC50 <50). The data underscore the importance of surveillance for breakthrough infections that result in severe COVID-19 and suggest the benefit of a second immunization following Ad26.COV2.S to increase protection against the variants.

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Tada, T., Zhou, H., Samanovic, M. I., Dcosta, B. M., Cornelius, A., Mulligan, M. J., Landau, N. R.. 2021-07-19. Comparison of Neutralizing Antibody Titers Elicited by mRNA and Adenoviral Vector Vaccine against SARS-CoV-2 Variants. https://doi.org/10.1101/2021.07.19.452771

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