Figure 4

Neutralizing antibodies against the virus variants in the serum samples collected from vaccinated individuals at Day 57. Neutralizing antibody titers against (a) spike protein-bearing pseudoviruses and (b) live virus variants are shown. Selected samples from the immunogenicity subset (n = 24/group) were assessed for neutralizing antibody titer testing, and the sampling ensured no significant differences in age and neutralizing antibody titer against live wildtype virus on Day 57 compared with the entire cohort. The solid and open circles represent individual values for the S-268019-b and ChAdOx1 nCoV-19 groups, respectively. Titer values reported as below the LLoQ were replaced with 0.5 × LLoQ. Each bar represents the GMT with error bars indicating 95% CI. Samples were selected from the immunogenicity subset (n = 24/group) assessed on Day 57, and sampling ensured no significant differences in age and neutralizing antibody titer against live wildtype virus on Day 57 compared with the entire cohort. The 95% CIs were constructed using Student’s t distribution for log-transformed titers. CI, confidence interval; GMT, geometric mean titer; LLoQ, lower limit of quantification; NT50, serum titers at which 50% neutralization was achieved.