Table 2.
Vaccine Efficacy in the ZOE-50 and ZOE-70 Studies and the Current Long-Term Follow-up Study After at Least 2 Additional Years of Follow-up
| Adjuvanted Recombinant Zoster Vaccine | Historical Controla/Placebo Group in ZOE-50 and ZOE-70b | Vaccine Efficacy, % (95% Confidence Interval) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| N | n | Sum of Follow-up Years | Incidence (per 1000 Person-Years) | N | n | Sum of Follow-up Years | Incidence (per 1000 Person-Years) | ||
| Vaccine efficacy in the current follow-up study: primary objective (up to the data lock point for the interim analysis in the current follow-up study) | |||||||||
| Overalla | 7277 | 27 | 19 621.7 | 1.4 | 7277 | 169 | 19 621.7 | 8.6 | 84.0 (75.9–89.8) |
| Vaccine efficacy from 1 month post-dose 2: secondary objective (up to the data lock point for the interim analysis in the current follow-up study) | |||||||||
| Overall | 13 881 | 59 | 72 744.6 | 0.8 | 13 881 | 651 | 72 744.6 | 8.9 | 90.9 (88.2–93.2) |
| Year 1b | 13 881 | 3 | 13 744.5 | 0.2 | 14 035 | 130 | 13 823.3 | 9.4 | 97.7 (93.1–99.5) |
| Year 2b | 13 569 | 10 | 13 415.6 | 0.7 | 13 564 | 136 | 13 332.5 | 10.2 | 92.7 (86.2–96.6) |
| Year 3b | 13 185 | 9 | 13 016.1 | 0.7 | 13 074 | 116 | 12 834.0 | 9.0 | 92.4 (85.0–96.6) |
| Year 4b | 12 757 | 10 | 12 946.7 | 0.8 | 12 517 | 95 | 12 637.4 | 7.5 | 89.8 (80.3–95.2) |
| Year 6a | 7277 | 10 | 7208.8 | 1.4 | 7277 | 66 | 7208.8 | 9.2 | 84.9 (70.4–93.1) |
| Year 7a | 7097 | 10 | 6993.1 | 1.4 | 7097 | 68 | 6993.1 | 9.7 | 85.3 (71.3–93.3) |
| Year 8 a,c | 6876 | 7 | 5160.2 | 1.4 | 6876 | 44 | 5160.2 | 8.5 | 84.1 (64.4–94.0) |
No data are available for year 5 because that period corresponds to the gap between ZOE-50 and ZOE-70 and the current follow-up study. The follow-up ceased at the first occurrence of a confirmed herpes zoster (HZ) episode. N is the number of individuals included in each group; n is the number of individuals having at least 1 confirmed herpes zoster episode.
Abbreviations: ZOE-50, pivotal phase 3 clinical trial of RZV in adults aged ≥50 years; ZOE-70, pivotal phase 3 clinical trial of RZV in adults aged ≥70 years.
aAdjuvanted recombinant zoster vaccine (RZV) vs matched historical controls from the placebo group in the ZOE-50/70 studies, adjusted for age and region at randomization during the ZOE-50/70 studies. The same N and follow-up period were considered for the historical control and vaccinated group. n for historical controls represents the projected number of included placebo group participants from ZOE-50/70 with at least 1 confirmed HZ episode based on the estimated incidence rate.
bRZV vs placebo recipients from the ZOE-50/70 trials adjusted for region.
cAt the data lock point for the interim analysis in the current follow-up study, data collection for year 8 was still incomplete.
P < .0001 for all vaccine efficacy estimates.