Four-plex S-2P and N bAb responses over the 6 different visits. A, Four-plex S-2P bAb concentrations in (coral, solid line) placebo arm COVID-19 cases and (turquoise, dashed line) vaccine arm COVID-19 cases by visit day. B, Anti-N bAb concentrations in (coral, solid line) placebo arm cases and (turquoise, dashed line) vaccine arm cases by visit day. C, Mean anti-S-2P and N bAb concentrations for (left panel) placebo arm and (right panel) vaccine arm COVID-19 cases at disease day 1, disease day 29, and the participant decision visit, along with the mean viral load at disease day 1 and over the 28 days of convalescence. Dashed gray lines in (A) and (B) are the positivity cutoff. Abbreviations: bAb, binding antibody; COVID-19, coronavirus disease 2019.