Table 1.
Baseline clinical and demographic characteristics of Japanese participants who received booster vaccination with VLPCOV-02 by dose and age cohort
| Characteristic | VLPCOV-02 1 μg |
VLPCOV-02 3 μg |
VLPCOV-02 7.5 μg |
VLPCOV-02 15 μg |
Total population |
|||||
|---|---|---|---|---|---|---|---|---|---|---|
| Non-elderly |
Elderly |
Non-elderly |
Elderly |
Non-elderly |
Elderly |
Non-elderly |
Elderly |
Non-elderly |
Elderly |
|
| n = 12 | n = 12 | n = 12 | n = 12 | n = 12 | n = 12 | n = 12 | n = 12 | n = 48 | n = 48 | |
| Age (years) | ||||||||||
| Mean ± SD | 52.3 ± 6.39 | 67.5 ± 2.88 | 52.8 ± 6.93 | 68.1 ± 2.31 | 50.8 ± 7.31 | 68.7 ± 3.28 | 54.0 ± 8.32 | 68.6 ± 2.68 | 52.5 ± 7.1 | 68.2 ± 2.8 |
| Median (range) | 52.0 (40–64) | 67.0 (65–73) | 54.0 (35–61) | 68.0 (65–71) | 52.0 (36–63) | 68.0 (65–75) | 57.0 (36–64) | 68.0 (66–74) | 53.0 (35–64) | 67.5 (65–75) |
| Sex, n (%) | ||||||||||
| Male | 6 (50.0) | 5 (41.7) | 4 (33.3) | 7 (58.3) | 5 (41.7) | 6 (50.0) | 4 (33.3) | 8 (66.7) | 19 (39.6) | 26 (54.2) |
| Female | 6 (50.0) | 7 (58.3) | 8 (66.7) | 5 (41.7) | 7 (58.3) | 6 (50.0) | 8 (66.7) | 4 (33.3) | 29 (60.4) | 22 (45.8) |
| History of confirmed COVID-19 infection, n (%) | ||||||||||
| Yes | 2 (16.7) | 1 (8.3) | 4 (33.3) | 4 (33.3) | 5 (41.7) | 2 (16.7) | 2 (16.7) | 3 (25.0) | 13 (27.1) | 10 (20.8) |
| No | 10 (83.3) | 11 (91.7) | 8 (66.7) | 8 (66.7) | 7 (58.3) | 10 (83.3) | 10 (83.3) | 9 (75.0) | 35 (72.9) | 38 (79.2) |
| Anti–N-protein antibody, n (%) | ||||||||||
| Positive | 1 (8.3) | 2 (16.7) | 3 (25.0) | 2 (16.7) | 0 (0) | 1 (8.3) | 1 (8.3) | 2 (16.7) | 5 (10.4) | 7 (14.6) |
| Negative | 11 (91.7) | 10 (83.3) | 9 (75.0) | 10 (83.3) | 12 (100) | 11 (91.7) | 11 (91.7) | 10 (83.3) | 43 (89.6) | 41 (85.4) |
| Baseline anti-RBD antibody titera | ||||||||||
| Geometric mean | 5260.6 | 10,099.2 | 13,066.9 | 13,188.8 | 13,130.6 | 12,771.3 | 12,660.6 | 21,877.2 | 10,339.2 | 13.889.3 |
| Min, Max | 1730, 51,000 |
732, ≥80,000 |
835, 62,900 |
1330, ≥80,000 |
1260, 42,800 |
1860, 58,800 |
4060, 66,800 |
2780, ≥80,000 |
835, 66,800 |
732, ≥80,000 |
| Number of prior SARS-CoV-2 vaccines, n (%)b | ||||||||||
| 2 | 1 (8.3) | 1 (8.3) | 0 (0) | 0 (0) | 3 (25.0) | 1 (8.3) | 2 (16.7) | 0 (0) | 6 (12.5) | 2 (4.2) |
| 3 | 9 (75.0) | 4 (33.3) | 9 (75.0) | 4 (33.3) | 6 (50.0) | 2 (16.7) | 5 (41.7) | 2 (16.7) | 29 (60.4) | 12 (25.0) |
| 4 | 2 (16.7) | 7 (58.3) | 3 (25.0) | 8 (66.7) | 3 (25.0) | 8 (66.7) | 4 (33.3) | 2 (16.7) | 12 (25.0) | 25 (52.1) |
| 5 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (8.3) | 1 (8.3) | 8 (66.7) | 1 (2.1) | 9 (18.8) |
| Months since last vaccine | ||||||||||
| Median | 12.1 | 8.1 | 12.3 | 8.7 | 11.8 | 8.2 | 13.0 | 6.2 | 12.2 | 7.8 |
| Range | 6.1–19.5 | 6.0–18.6 | 6.1–13.4 | 6.0–16.3 | 6.0–21.0 | 6.1–22.0 | 6.0–20.5 | 6.0–14.9 | 6.0–21.0 | 6.0–22.0 |
COVID-19, coronavirus disease 2019; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; SD, standard deviation.
a
The maximum titer measurable was 80,000; any values ≥ 80,000 were treated as 80,000 for the purposes of calculating the geometric mean value.
b
All participants had received at least a two-dose primary vaccination series with the same COVID-19 uridine-modified RNA vaccine or a booster inoculation with an mRNA vaccine (any kind, any number, and including bivalent mRNA vaccines) ≥6 months previously.