Table 5. Vibriocidal antibody titers and proportion of ≥ 4 fold rise from baseline GMT in children.
| Children | O1 Inaba | O1 Ogawa | O139 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 14 day interval (n = 84) | 28 day interval (n = 82) | p value | 14 day interval (n = 83) | 28 day interval (n = 81) | p value | 14 day interval (n = 82) | 28 day interval (n = 80) | p value | ||
| Baseline 14 days after first vaccine dose | GMT a (95% CI) | 47.2 (29.1, 76.5) | 88.5 (56.1, 140) | 0.06 | 124.5 (75.7, 205) | 131 (77.5, 223) | 0.88 | 3.7 (3.0, 4.5) | 3.7 (2.9, 4.6) | 0.95 |
| GMT a (95% CI) | 1402 (894.1, 2197) | 1841 (1267, 2676) | 0.36 | 2335 (1656, 3294) | 2049 (1423, 2952) | 0.60 | 10.9 (7.8,15.4) | 12.3 (9,16.9) | 0.62 | |
| GMF rise b (95% CI) | 29.7 (18.2, 48.6) | 20.8 (13.5, 32) | 0.28 | 18.7 (11.9, 29.5) | 15.6 (10.3, 23.5) | 0.55 | 3 (2.2, 4.1) | 3.3 (2.5, 4.4) | 0.62 | |
| N (%) who seroconverted c | 72 (86%) | 73 (89%) | 0.52 | 63 (75%) | 65 (79%) | 0.51 | 34 (40%) | 36 (44%) | 0.65 | |
| 95% CI d | 76.7%- 91.6% | 80.4%- 94.1% | 65%-83% | 69%-87% | 31%-51% | 34%-55% | ||||
| 14 days after second vaccine dose | GMT a (95% CI) | 827 (553, 1235) | 952 (676, 1341) | 0.60 | 1380 (992, 1920) | 1025 (702, 1496) | 0.24 | 7.8 (5.7,10.7) | 7.2 (5.3, 9.8) | 0.70 |
| GMF rise b (95% CI) | 17.5 (11.4, 26.9) | 10.7 (7.5, 15.5) | 0.09 | 11.1 (7.5, 16.4) | 7.80 (5.2, 11.6) | 0.21 | 2.1 (1.7, 2.7) | 1.9 (1.5, 2.43) | 0.57 | |
| N (%) who seroconverted c | 67 (80%) | 63 (77%) | 0.65 | 61 (73%) | 59 (72%) | 0.92 | 23 (27%) | 21 (26%) | 0.80 | |
| 95% CI d | 70%- 87% | 66.6%- 84.6% | 62%-81% | 61%-81% | 19%-38% | 17%-36% | ||||
| N (%) who seroconverted following either first or second dose | 74 (88%) | 75 (91%) | 0.47 | 67 (81%) | 69 (85%) | 0.45 | 37 (45%) | 40 (50%) | 0.53 | |
| Proportion difference (Lower boundary of one-tailed 95% CI) e | -- | -3% (-13.6%) | -- | -- | -1% (-12.1%) | -- | -- | -1.8% (-13%) | -- | |
aGeometric mean reciprocal titers
bGeometric mean-fold rise from baseline to 14 days after first dose or from baseline to 14 days after second dose
c # with ≥4 fold rise in titers from baseline to 14 days after first dose or from baseline to 14 days after second dose
d 95% confidence intervals using Wilson Score method
e Primary endpoint. Difference in seroconversion rates after second dose were calculated by subtracting 14 day interval from 28 day interval. The 28 days interval group is non-inferior to the 14 day interval group as the lower limit of the proportion difference is greater than pre-defined cut-off (-20%)