Table 4. Vibriocidal antibody titers and proportion of ≥ 4 fold rise from baseline GMT in adults.
| Adults | O1 Inaba | O1 Ogawa | O139 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 14 day interval (n = 86) | 28 day interval (n = 84) | p value | 14 day interval (n = 86) | 28 day interval (n = 84) | p value | 14 day interval (n = 86) | 28 day interval (n = 84) | p value | ||
| Baseline | GMTa (95% CI) | 191.0 (133, 275) | 143.7 (94.2, 219) | 0.31 | 364 (252, 526) | 359 (244, 528) | 0.96 | 5.4 (4.2, 6.9) | 4.9 (3.9, 6.3) | 0.62 |
| 14 days after first vaccine dose | GMTa (95% CI) | 1301 (1032, 1639) | 1280 (954, 1717) | 0.93 | 2076 (1660, 2596) | 2083 (1636, 2651) | 0.98 | 9.9 (7.5,13.2) | 9.6 (7.2,12.9) | 0.85 |
| GMF rise b (95% CI) | 6.8 (5.0, 9.3) | 8.9 (6.0, 13.3) | 0.30 | 5.7 (4.1, 8.0) | 5.8 (4.2, 7.9) | 0.94 | 1.8 (1.5, 2.3) | 1.9 (1.5, 2.5) | 0.77 | |
| N (%) who seroconverted c | 59 (69%) | 55 (66%) | 0.66 | 48 (56%) | 52 (62%) | 0.42 | 22 (26%) | 23 (27%) | 0.79 | |
| 95% CI d | 58.2%– 77.4% | 54.8%- 74.8% | 45%-66% | 51%-72% | 18%-36% | 19%-38% | ||||
| 14 days after second vaccine dose | GMTa (95% CI) | 876 (687, 1117) | 678 (529, 868) | 0.14 | 1492 (1219, 1825) | 1356 (1089, 1689) | 0.53 | 8.4 (6.4,11.1) | 8.9 (6.5,12.1) | 0.80 |
| GMF rise b (95% CI) | 4.6 (3.4, 6.2) | 4.7 (3.4, 6.4) | 0.90 | 4.1 (3.0, 5.6) | 3.8 (2.9, 4.9) | 0.70 | 1.6 (1.3, 1.8) | 1.8 (1.4, 2.3) | 0.33 | |
| No (%) who seroconverted c | 47 (55%) | 49 (58%) | 0.63 | 39 (45%) | 41 (49%) | 0.65 | 17 (20%) | 17 (20%) | 0.94 | |
| 95% CI d | 44.2%- 64.7% | 47.7%- 68.3% | 35%-56% | 38%-59% | 13%-29% | 13%-30% | ||||
| N (%) who seroconverted following either first or second dose | 59 (69%) | 56 (67%) | 0.79 | 50 (58%) | 53 (63%) | 0.51 | 23 (27%) | 25 (30%) | 0.66 | |
| Proportion difference (Lower boundary of one-tailed 95% CI) e | -- | 3% (-8.6%) | -- | -- | 4% (-8.9%) | -- | -- | 0.5% (-9.9%) | -- | |
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%)