Table 4.
Vaccine Efficacy of a First RSVPreF3 OA Dose Followed by Revaccination 1 Year Later Against a First Occurrence of RSV-LRTD and RSV-ARI Over 2 RSV Seasons Post–Dose 1 (Modified Exposed Population)
| RSVPreF3 OA (revaccination) | Placebo | Vaccine Efficacy With Season as a Covariate, % (CIa) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Endpoint | N | n | T, person-years | n/T, n/1000 person-years | N | n | T, person-years | n/T, n/1000 person-years | |
| RSV-LRTD | |||||||||
| Overall | 12 469 | 30 | 14 660.5 | 2.0 | 12 498 | 139 | 17 269.0 | 8.0 | 67.1 (48.1, 80.0) |
| Severeb | 12 469 | 7 | 14 672.9 | 0.5 | 12 498 | 48 | 17 320.6 | 2.8 | 78.8 (52.5, 92.0) |
| By subtypec | |||||||||
| RSV-A | 12 469 | 13 | 14 670.0 | 0.9 | 12 498 | 48 | 17 323.5 | 2.8 | 55.9 (16.8, 78.2) |
| RSV-B | 12 469 | 17 | 14 666.1 | 1.2 | 12 498 | 90 | 17 297.6 | 5.2 | 72.1 (52.5, 84.5) |
| By age | |||||||||
| ≥70 y | 5506 | 16 | 6434.8 | 2.5 | 5517 | 65 | 7614.9 | 8.5 | 61.9 (33.0, 79.6) |
| ≥80 y | 1017 | 4 | 1153.9 | 3.5 | 1028 | 10 | 1384.4 | 7.2 | 38.6 (−117.2, 86.2) |
| 60–69 y | 6963 | 14 | 8225.6 | 1.7 | 6981 | 74 | 9654.1 | 7.7 | 71.6 (48.9, 85.2) |
| 70–79 y | 4489 | 12 | 5280.9 | 2.3 | 4489 | 55 | 6230.4 | 8.8 | 66.2 (35.7, 83.6) |
| By co-existing condition of interestd | |||||||||
| No condition | 7486 | 18 | 8788.0 | 2.0 | 7579 | 67 | 10 478.1 | 6.4 | 58.5 (28.8, 76.9) |
| ≥1 condition | 4983 | 12 | 5872.5 | 2.0 | 4919 | 72 | 6790.9 | 10.6 | 75.1 (53.6, 87.8) |
| ≥1 cardiorespiratory condition | 2546 | 7 | 2987.5 | 2.3 | 2479 | 56 | 3411.6 | 16.4 | 81.3 (58.6, 92.9) |
| ≥1 endocrine or metabolic condition | 3229 | 7 | 3814.7 | 1.8 | 3255 | 32 | 4509.4 | 7.1 | 67.5 (24.2, 88.0) |
| By frailtye | |||||||||
| Frail | 189 | 1 | 209.4 | 4.8 | 177 | 1 | 230.7 | 4.3 | 13.6 (−6751.4, 98.9) |
| Pre-frail | 4794 | 7 | 5561.0 | 1.3 | 4779 | 47 | 6478.5 | 7.3 | 77.3 (49.1, 91.4) |
| Fit | 7465 | 22 | 8867.6 | 2.5 | 7522 | 89 | 10 533.7 | 8.4 | 62.2 (38.8, 77.5) |
| RSV-ARI | |||||||||
| Overall | 12 469 | 80 | 14 630.1 | 5.5 | 12 498 | 292 | 17 167.0 | 17.0 | 60.3 (48.8, 69.5) |
Analysis includes RSV season 1 data from participants who received dose 1 (vaccine or placebo) and season 2 data from participants who received dose 1 and dose 2 (2 vaccine doses or 2 placebo doses). Season 1 data were collected from day 15 post–dose 1 until dose 2 administration or until 30 September 2022 (end of Southern Hemisphere season 1) for participants who did not receive dose 2. Season 2 data were collected from dose 2 until 31 March 2023 (end of Northern Hemisphere season 2). Participants who received vaccine as dose 1 and placebo as dose 2 (RSV_1dose group) contributed to season 1 but were censored before dose 2 administration. Participants who received 2 vaccine doses (RSV_revaccination group) contributed to both seasons. Vaccine efficacy was estimated using a Poisson model adjusted for age, region, and season, except for the analysis by age, which used region and season as covariates.
Abbreviations: CI, confidence interval; n, number of participants with ≥1 RSV-LRTD or RSV-ARI; N, number of participants in the modified exposed population; n/T, incidence rate of participants reporting at least 1 event; RSV, respiratory syncytial virus; RSV-ARI, RSV-related acute respiratory illness; RSV-LRTD, RSV-related lower respiratory tract disease confirmed by the adjudication committee; RSVPreF3 OA, RSV prefusion F protein–based vaccine; T, sum of follow-up time (from day 15 post–dose 1 until first occurrence of the event, data lock point, or drop-out).
a97.5% CI for confirmatory secondary endpoint (RSV-LRTD, overall); 95% CI for other endpoints.
bSevere disease according to either of the 2 case definitions (definition 1 based on clinical signs/investigator assessment or definition 2 based on supportive therapy; see Supplementary Methods). All severe cases met case definition 1; no cases in the vaccine group and 5 in placebo were confirmed by the adjudication committee as also meeting case definition 2.
cRSV subtype was unknown for 1 RSV-LRTD case (placebo group).
dConditions of interest are as explained in Table 1, footnote c.
eFrailty status was assessed using a gait speed test as explained in Table 1, footnote b.