TY - JOUR T1 - Comparison of Neutralizing Antibody Titers Elicited by mRNA and Adenoviral Vector Vaccine against SARS-CoV-2 Variants JF - bioRxiv DO - 10.1101/2021.07.19.452771 SP - 2021.07.19.452771 AU - Takuya Tada AU - Hao Zhou AU - Marie I. Samanovic AU - Belinda M. Dcosta AU - Amber Cornelius AU - Mark J. Mulligan AU - Nathaniel R. Landau Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/07/21/2021.07.19.452771.abstract N2 - 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.Competing Interest StatementThe authors have declared no competing interest. ER -