Immunogenicity of Ad26.COV2.S vaccine against SARS-CoV-2 variants in humans

Abstract The Ad26.COV2.S vaccine 1–3 has demonstrated clinical efficacy against symptomatic COVID-19, including the B.1.351 variant that is partially resistant to neutralizing antibodies 1 . However, immunogenicity of this in humans SARS-CoV-2 variants concern remains unclear. Here we report humoral and cellular immune responses from 20 vaccinated individuals COV1001 phase I–IIa trial 2 original strain WA1/2020 as well B.1.1.7, CAL.20C, P.1 concern. induced median pseudovirus antibody titres were 5.0-fold 3.3-fold lower variants, respectively, compared with on day 71 after vaccination. Median binding 2.9-fold 2.7-fold WA1/2020. Antibody-dependent phagocytosis, complement deposition natural killer cell activation largely preserved variant. CD8 CD4 T responses, central effector memory comparable among WA1/2020, B.1.351, CAL.20C variants. These data show by reduced but functional non-neutralizing findings have implications for protection