Table 2.
Vaccine Efficacy of a Single Dose of RSVPreF3 OA Against a First Occurrence of RSV-LRTD and RSV-ARI Over 2 RSV Seasons (Modified Exposed Population)
| RSVPreF3 OA (1 Dose) | Placebo | Vaccine Efficacy, % (CIa) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Endpoint | N | n | T, person-years | n/T, n/1000 person-years | N | n | T, person-years | n/T, n/1000 person-years | With Season as a Covariate | Without Season as a Covariate |
| RSV-LRTD | ||||||||||
| Overall | 12 469 | 30 | 14 662.6 | 2.0 | 12 498 | 139 | 17 269.0 | 8.0 | 67.2 (48.2, 80.0) | 74.5 (60.0, 84.5) |
| Severeb | 12 469 | 7 | 14 672.6 | 0.5 | 12 498 | 48 | 17 320.6 | 2.8 | 78.8 (52.6, 92.0) | 82.7 (61.6, 93.4) |
| By subtypec | ||||||||||
| RSV-A | 12 469 | 6 | 14 673.7 | 0.4 | 12 498 | 48 | 17 323.5 | 2.8 | 80.5 (54.0, 93.2) | 85.2 (65.4, 94.8) |
| RSV-B | 12 469 | 24 | 14 665.5 | 1.6 | 12 498 | 90 | 17 297.6 | 5.2 | 59.7 (35.8, 75.5) | 68.5 (50.2, 80.8) |
| By age | ||||||||||
| ≥70 y | 5506 | 13 | 6419.5 | 2.0 | 5517 | 65 | 7614.9 | 8.5 | 69.3 (43.4, 84.6) | 76.4 (56.7, 88.1) |
| ≥80 y | 1017 | 4 | 1151.2 | 3.5 | 1028 | 10 | 1384.4 | 7.2 | 38.4 (−118.2, 86.1) | 52.6 (−64.2, 89.2) |
| 60–69 y | 6963 | 17 | 8243.0 | 2.1 | 6981 | 74 | 9654.1 | 7.7 | 65.4 (40.4, 80.9) | 72.9 (53.7, 85.0) |
| 70–79 y | 4489 | 9 | 5268.3 | 1.7 | 4489 | 55 | 6230.4 | 8.8 | 74.9 (48.4, 89.2) | 80.7 (60.6, 91.6) |
| By co-existing condition of interestd | ||||||||||
| No condition | 7486 | 14 | 8779.7 | 1.6 | 7579 | 67 | 10 478.1 | 6.4 | 68.3 (42.7, 83.6) | 75.0 (55.1, 87.0) |
| ≥1 condition | 4983 | 16 | 5882.9 | 2.7 | 4919 | 72 | 6790.9 | 10.6 | 66.7 (41.8, 82.0) | 74.5 (55.7, 86.1) |
| ≥1 cardiorespiratory condition | 2546 | 10 | 2997.5 | 3.3 | 2479 | 56 | 3411.6 | 16.4 | 73.8 (47.9, 88.2) | 80.1 (60.6, 91.0) |
| ≥1 endocrine or metabolic condition | 3229 | 8 | 3822.6 | 2.1 | 3255 | 32 | 4509.4 | 7.1 | 63.1 (17.4, 85.4) | 70.6 (34.8, 88.3) |
| By frailtye | ||||||||||
| Frail | 189 | 2 | 213.5 | 9.4 | 177 | 1 | 230.7 | 4.3 | −147.9 (−15 796.3, 88.2) | −116.3 (−12 773.1, 88.9) |
| Pre-frail | 4794 | 8 | 5537.3 | 1.4 | 4779 | 47 | 6478.5 | 7.3 | 73.3 (42.4, 89.2) | 80.0 (57.3, 91.8) |
| Fit | 7465 | 20 | 8891.0 | 2.2 | 7522 | 89 | 10 533.7 | 8.4 | 66.2 (44.3, 80.4) | 73.4 (56.5, 84.5) |
| RSV-ARI | ||||||||||
| Overall | 12 469 | 94 | 14 626.4 | 6.4 | 12 498 | 292 | 17 167.0 | 17.0 | 52.7 (40.0, 63.0) | 62.1 (52.1, 70.3) |
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 (vaccine or placebo) and dose 2 (placebo). 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 both seasons. Participants who received 2 vaccine doses (RSV_revaccination group) contributed to season 1 but were censored before dose 2 administration. Vaccine efficacy was estimated using a Poisson model adjusted for age, region, and season (“with season as covariate”) or for age and region (“without season as covariate”; post hoc analyses), except for the analysis by age, which used region and season or region only 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; 1 case 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.