Table 2.
Noninferiority of the RSVPreF3 OA Immune Response at 1 Month Post-vaccination in Adults 50–59 Years Old Without or With an Increased Risk for RSV Disease Versus Adults ≥60 Years Old (Per-Protocol Set for Humoral Immunogenicity)
| Comparison Endpoint |
Adjusted GMT Ratio (CIa) (≥60 Group Over 50–59 Group) | Sero-response Rate Difference (CIa) (≥60 Group Minus 50–59 Group) |
Success Criterion Metb |
|---|---|---|---|
| ≥60-RSV vs 50–59-non-AIR-RSV | |||
| RSV-A neutralization titer | .95 (.83, 1.09) | −2.41 (−8.30, 3.50) | Yes |
| RSV-B neutralization titer | .89 (.77, 1.03) | −3.73 (−11.09, 3.68) | Yes |
| ≥60-RSV vs 50–59-AIR-RSV | |||
| RSV-A neutralization titer | .83 (.73, .95) | −6.47 (−12.05, −0.94) | Yes |
| RSV-B neutralization titer | .80 (.71, .91) | −7.15 (−13.34, −0.94) | Yes |
Sero-response rate was defined as the percentage of participants with a ≥4-fold increase in neutralization titers from pre- to 1 month post-vaccination.
Abbreviations: CI, confidence interval; GMT, geometric mean titer; 50–59-AIR-RSV, group of 50–59-year-old participants at increased risk for respiratory syncytial virus (RSV) disease who received RSV prefusion F protein–based vaccine (RSVPreF3 OA); 50–59-non-AIR-RSV, group of 50–59-year-old participants without increased risk for RSV disease who received RSVPreF3 OA; ≥60-RSV, group of ≥60-year-old participants who received RSVPreF3 OA.
a95% CI (alpha of .025) for all comparisons except for ≥60-RSV vs 50–59-non-AIR-RSV for RSV-B neutralization titers, which used a 97.5% CI (alpha of .0125); alpha determined following the graphical testing procedure explained in the Supplementary Methods.
bCriterion was met if the upper limit of the CI around the adjusted GMT ratio was ≤1.5 and the upper limit of the CI around the sero-response rate difference was ≤10%.