Immunogenicity of Ad26.COV2.S vaccine against SARS-CoV-2 variants in humans
Galit Alter, Jingyou Yu, Jinyan Liu, Abishek Chandrashekar, Erica N. Borducchi, Lisa H. Tostanoski, Katherine McMahan, Catherine Jacob-Dolan, David R. Martinez, Aiquan Chang, Tochi Anioke, Michelle A. Lifton, Joseph P. Nkolola, Kathryn E. Stephenson, Caroline Atyeo, Sally Shin, Paul Fields, Ian M. Kaplan, Harlan Robins, Fatima Amanat, Florian Krammer, Ralph S. Baric, Mathieu Le Gars, Jerald Sadoff, Anne Marit de Groot, Dirk Heerwegh, Frank Struyf, Macaya Douoguih, Johan Van Hoof, Hanneke Schuitemaker, Dan H. Barouch
Abstract
Abstract The Ad26.COV2.S vaccine 1–3 has demonstrated clinical efficacy against symptomatic COVID-19, including against the B.1.351 variant that is partially resistant to neutralizing antibodies 1 . However, the immunogenicity of this vaccine in humans against SARS-CoV-2 variants of concern remains unclear. Here we report humoral and cellular immune responses from 20 Ad26.COV2.S vaccinated individuals from the COV1001 phase I–IIa clinical trial 2 against the original SARS-CoV-2 strain WA1/2020 as well as against the B.1.1.7, CAL.20C, P.1 and B.1.351 variants of concern. Ad26.COV2.S induced median pseudovirus neutralizing antibody titres that were 5.0-fold and 3.3-fold lower against the B.1.351 and P.1 variants, respectively, as compared with WA1/2020 on day 71 after vaccination. Median binding antibody titres were 2.9-fold and 2.7-fold lower against the B.1.351 and P.1 variants, respectively, as compared with WA1/2020. Antibody-dependent cellular phagocytosis, complement deposition and natural killer cell activation responses were largely preserved against the B.1.351 variant. CD8 and CD4 T cell responses, including central and effector memory responses, were comparable among the WA1/2020, B.1.1.7, B.1.351, P.1 and CAL.20C variants. These data show that neutralizing antibody responses induced by Ad26.COV2.S were reduced against the B.1.351 and P.1 variants, but functional non-neutralizing antibody responses and T cell responses were largely preserved against SARS-CoV-2 variants. These findings have implications for vaccine protection against SARS-CoV-2 variants of concern.