Fig. 2: IgG purified from human Ad26.COV2.S vaccine recipients attenuates SARS-CoV-2-associated clinical disease in hamsters.

One day post-IgG transfer, groups of hamsters were challenged with WA1/2020 SARS-CoV-2 via the intranasal route. Post-challenge, hamsters were monitored for fourteen days for signs of clinical disease (i.e., weight loss). a Data shown represent the median body weight change for the following groups: negative control (buffer only), positive control (NHP IgG), or each of the N = 5 clinical trial study participants that received a placebo immunization. b Data shown represent the median of the groups corresponding to the N = 20 participants who received Ad26.COV2.S vaccine at the indicated dosing regimens. For reference, the buffer only and NHP IgG data are reproduced in panel b to allow for comparison of experimental groups with negative and positive controls. c, d The maximum body weight change was calculated for each hamster in the study. Data points displayed in panel c correspond to the group median maximum body weight change for each group of hamsters that corresponds to one study participant. Horizontal lines indicate the group medians and statistics indicated are the results of a two-sided Mann-Whitney test, comparing vaccinees to placebo controls. In panel d, maximum body weight change is displayed for each individual hamster receiving IgG from Ad26.COV2.S vaccinees, placebo control IgG, or the control groups of buffer only or convalescent NHP IgG. Horizontal lines indicate medians. Statistics displayed are the results of a Kruskal-Wallis test with Dunn’s multiple comparisons test; for clarity, the comparison of vaccinees vs. placebo is indicated on the plot, while the p values comparing the buffer only control to the indicated groups are displayed next to the plot.