Table 1.
Immune response for haemagglutination-inhibition (HI) antibodies against A/California/7/2009 H1N1 in adults aged 18 to 60 years and in adults >60 years (per-protocol immunogenicity cohorts)
| |
N |
Seroprotection rate (titre ≥ 1:40) % (95% CI) |
Seroconversion rate* % (95% CI) |
Geometric Mean Fold Rise** (95% CI) |
N |
Seroprotection rate (titre ≥ 1:40) % (95% CI) |
Seroconversion rate* % (95% CI) |
Geometric Mean Fold Rise** (95% CI) |
|---|---|---|---|---|---|---|---|---|
| Vaccinated on Day 0 (subjects from Groups A and B pooled) 18–60 years | Vaccinated on Day 0 (subjects from Groups A and B pooled) 18>60 years | |||||||
|
Day 0 (Prevaccination) |
160 |
14.4 |
- |
- |
136 |
5.1 |
- |
- |
| (9.3-20.8) |
|
|
|
(2.1-10.3) |
|
|
||
|
Day 21 |
160 |
97.5 |
96.3 |
45.0 |
136 |
91.9 |
89.0 |
23.4 |
| (93.7-99.3) |
(92.0-98.6) |
(37.3-54.5) |
|
(86.0-95.9) |
(82.5-93.7) |
(19.1-28.7) |
||
| |
Group A Vaccinated on Day 0 and Day 21 18–60 years |
Group A Vaccinated on Day 0 and Day 21 >60 years |
||||||
|
Day 0 (Prevaccination) |
87 |
12.6 |
- |
- |
83 |
7.2 |
- |
- |
| (6.5-21.5) |
|
- |
|
(2.7-15.1) |
|
|
||
|
Day 21 |
87 |
100 |
100 |
51.6 |
83 |
90.4 |
89.2 |
23.0 |
| (95.8-100) |
(95.8-100) |
(40.7-65.5) |
|
(81.9-95.7) |
(80.4-94.9) |
(17.7-29.9) |
||
|
Day 42 |
87 |
100 |
98.9 |
86.7 |
83 |
100 |
98.8 |
54.9 |
| (95.8-100) |
(93.8-100) |
(68.6-109.5) |
|
(95.7-100) |
(93.5-100) |
(43.4-69.3) |
||
|
Day 182 |
85 |
97.6 |
92.9 |
26.6 |
83 |
90.4 |
86.7 |
13.4 |
| (91.8-99.7) |
(85.3-97.4) |
(20.8-34.0) |
|
(81.9-95.7) |
(77.5-93.2) |
(10.9-16.5) |
||
|
Day 203 |
|
- |
- |
- |
|
- |
- |
- |
|
Day 364 |
79 |
82.3 |
75.9 |
11.0 |
76 |
50.0 |
40.8 |
4.8 |
| (72.1-90.0) |
(65.0-84.9) |
(9.2-15.5) |
|
(38.3-61.7) |
(29.6-52.7) |
(3.8-6.1) |
||
| |
Group B Vaccinated on Day 0 and Day 182 18–60 years |
Group B Vaccinated on Day 0 and Day 182 >60 years |
||||||
|
Day 0 (Prevaccination |
67 |
14.9 (7.4-25.7) |
- |
- |
48 |
2.1 (0.1-11.1) |
- |
- |
|
Day 21 |
67 |
94.0 |
92.5 |
39.2 |
48 |
95.8 |
89.6 |
23.3 |
| (85.4-98.3) |
(83.4-97.5) |
(28.3-54.2) |
|
(85.7-99.5) |
(77.3-96.5) |
(16.6-32.7) |
||
|
Day 42 |
67 |
95.5 |
91.0 |
31.9 |
48 |
89.6 |
81.3 |
16.5 |
| (87.5-99.1) |
(81.5-96.6) |
(23.4-43.4) |
|
(77.3-96.5) |
(67.4-91.1) |
(11.8-23.0) |
||
|
Day 182 |
56 |
85.7 |
83.9 |
14.6 |
30 |
63.3 |
56.7 |
6.1 |
| (73.8-93.6) |
(71.7-92.4) |
(10.8-19.7) |
|
(43.9-80.1) |
(37.4-74.5) |
(3.9-9.4) |
||
|
Day 203 |
48 |
100 |
100 |
79.0 |
28 |
100 |
100 |
65.7 |
| (92.6-100) |
(92.6-100) |
(58.0-107.7) |
|
(87.7-100) |
(87.7-100) |
(41.4-104.1) |
||
| Day 364 | 60 |
93.3 |
90.0 |
17.3 |
46 |
80.4 |
73.9 |
8.3 |
| (83.8-98.2) | (79.5-96.2) | (13.0-23.0) | (66.1-90.6) | (58.9-85.7) | (6.0-11.3) | |||
*Seroconversion rate for haemagglutination-inhibition antibody response is defined as the percentage of vaccinees who have a prevaccination titre <1:10 and a post-vaccination titre ≥1:40, or a significant increase in antibody titre defined as the percentage of vaccinees who have a pre-vaccination titre ≥ 1:10 and at least a fourfold increase in post-vaccination titre. **Geometric mean fold rise is defined as geometric mean of the within-subject ratios of the post-vaccination reciprocal haemagglutination-inhibition titre to the Day 0 reciprocal agglutination-inhibition titre.
European Medicines Agency Committee for Medicinal Products for Human Use (CHMP) criteria for haemagglutination-inhibition antibody response in 18–60 year olds are: seroprotection rate >70%, seroconversion rate >40%, and geometric mean fold rise >2·5 and in adults >60 years are seroprotection rate >60%, seroconversion rate >30%, and geometric mean fold rise >2·0.
United States Center for Biologics Evaluation and Research (CBER) criteria for hemagglutination-inhibition antibody response in adults <65 years are: lower limit (LL) of 95% CI for seroprotection ≥70% and LL of 95% CI for seroconversion ≥40% and in adults ≥65 years are LL of 95% CI for seroprotection ≥60% and LL of 95% CI for seroconversion ≥30%.