Table 4.
Neutralizing antibody-based immunogenicity with 95% CI in the per-protocol immunogenicity cohort
| Month | 6 | 6 + 21 days | 12 | 12 + 21 | 24 | 36 | 36 + 21 | 48 | |
|---|---|---|---|---|---|---|---|---|---|
|
Titre ≥1:28 n/N; % (95% CI) |
Booster at Month 6 |
||||||||
| Primary strain |
162/163; 99.4 |
163/163; 100 |
75/75; 100 |
– |
74/75; 98.7 |
71/75; 94.7 |
– |
73/75; 97.3 |
|
| (96.6, 100) |
(97.8, 100) |
(95.2, 100) |
|
(92.8, 100) |
(86.9, 98.5) |
|
(90.7, 99.7) |
||
| Booster strain |
160/162; 98.8 |
162/162; 100 |
74/74; 100 |
– |
70/74; 94.6 |
66/75; 88.0 |
– |
67/75; 89.3 |
|
| (95.6, 99.9) |
(97.7, 100) |
(95.1, 100) |
|
(86.7, 98.5) |
(78.4, 94.4) |
|
(80.1, 95.3) |
||
|
Booster Month 12 | |||||||||
| Primary strain |
– |
– |
162/164; 98.8 |
170/170; 100 |
75/75; 100 |
73/74; 98.6 |
– |
74/75; 98.7 |
|
| |
|
(95.7, 99.9) |
(97.9, 100) |
(95.2, 100) |
(92.7, 100) |
|
(92.8, 100) |
||
| Booster strain |
– |
– |
135/164; 82.3 |
170/170; 100 |
72/75; 96.0 |
69/74; 93.2 |
– |
73/75; 97.3 |
|
| |
|
(75.6, 87.8) |
(97.9, 100) |
(88.8, 99.2) |
(84.9, 97.8) |
|
(90.7, 99.7) |
||
|
Booster Month 36 | |||||||||
| Primary strain |
– |
– |
– |
– |
58/75; 77.3 |
55/75; 73.3 |
74/74; 100 |
74/75; 98.7 |
|
| |
|
|
|
(66.2, 86.2) |
(61.9, 82.9) |
(95.1, 100) |
(92.8, 100) |
||
| Booster strain |
– |
– |
– |
– |
17/75; 22.7 |
19/75; 25.3 |
75/75; 100 |
74/75; 98.7 |
|
| |
|
|
|
(13.8, 33.8) |
(16.0, 36.7) |
(95.2, 100) |
(92.8, 100) |
||
| |
Month |
6 |
6 + 21 days |
12 |
12 + 21 |
24 |
36 |
36 + 21 |
48 |
|
GMT value (95% CI) |
Booster at Month 6 |
||||||||
| Primary strain |
169.9; |
1566.3; |
159.4; |
– |
74.0; |
62.0; |
– |
71.4; |
|
| (152.3, 189.4) |
(1342.1, 1827.9) |
(128.1, 198.2) |
|
(62.5, 87.5) |
(52.1, 73.7) |
|
(61.8, 82.5) |
||
| Booster strain |
179.7; |
2702.0; |
134.0; |
– |
66.3; |
55.4; |
– |
54.5; |
|
| (161.8, 199.7) |
(2270.4, 3215.6) |
(107.4, 167.3) |
|
(54.5, 80.8) |
(45.5, 67.6) |
|
(45.8, 64.7) |
||
|
Booster Month 12 | |||||||||
| Primary strain |
– |
– |
204.1; |
2734.9; |
164.9; |
121.1; |
– |
117.4; |
|
| |
|
(179.9, 231.6) |
(2334.4, 3204.2) |
(125.7, 216.2) |
(91.7, 159.9) |
|
(92.7, 148.6) |
||
| Booster strain |
– |
– |
58.5; |
2363.2; |
148.9; |
106.9; |
– |
103.4; |
|
| |
|
(50.8, 67.3) |
(2037.5, 2740.9) |
(111.8, 198.3) |
(81.6, 140.0) |
|
(79.5, 134.4) |
||
|
Booster Month 36 | |||||||||
| Primary strain |
– |
– |
– |
– |
33.3; |
31.8; |
1373.4; |
429.0; |
|
| |
|
|
|
(28.8, 38.4) |
(27.3, 36.9) |
(1023.7, 1842.6) |
(322.2, 571.2) |
||
| Booster strain |
– |
– |
– |
– |
16.7; |
17.3; |
1154.3; |
320.4; |
|
| |
|
|
|
(15.4, 18.1) |
(15.8, 19.0) |
(847.8 1571.4) |
(243.7, 421.4) |
||
| |
Month |
6 |
6 + 21 days |
12 |
12 + 21 |
24 |
36 |
36 + 21 |
48 |
|
Booster SCR n/N;% (95% CI) |
Booster at Month 6 |
||||||||
| Primary strain |
– |
121/163; 74.2 |
7/75; 9.3 |
– |
1/75; 1.3 |
0/75; 0.0 |
– |
0/75; 0.0 |
|
| |
(66.8, 80.8) |
(3.8, 18.3) |
|
(0.0, 7.2) |
(0.0, 4.8) |
|
(0.0, 4.8) |
||
| Booster strain |
– |
144/162; 88.9 |
4/74; 5.4 |
– |
0/74; 0.0 |
0/75; 0.0 |
– |
1/75; 1.3 |
|
| |
(83.0, 93.3) |
(1.5, 13.3) |
|
(0.0, 4.9) |
(0.0, 4.8) |
|
(0.0, 7.2) |
||
|
Booster Month 12 | |||||||||
| Primary strain |
– |
– |
– |
141/164; 86.0 |
7/75; 9.3 |
5/74; 6.8 |
– |
2/75; 2.7 |
|
| |
|
|
(79.7, 90.9) |
(3.8, 18.3) |
(2.2, 15.1) |
|
(0.3, 9.3) |
||
| Booster strain |
– |
– |
– |
159/164; 97.0 |
34/75; 45.3 |
27/74; 36.5 |
– |
27/75; 36.0 |
|
| |
|
|
(93.0, 99.0) |
(33.8, 57.3) |
(25.6, 48.5) |
|
(25.2, 47.9) |
||
|
Booster Month 36 | |||||||||
| Primary strain |
– |
– |
– |
– |
– |
– |
73/74; 98.6 |
64/75; 85.3 |
|
| |
|
|
|
|
|
(92.7, 100) |
(75.3, 92.4) |
||
| Booster strain | – |
– |
– |
– |
– |
– |
75/75; 100 |
72/75; 96.0 |
|
| (95.2, 100) | (88.8, 99.2) | ||||||||
CI, confidence interval; n/N, number of subjects fulfilling definition of outcome/total number of subjects in group; GMT, geometric mean titer; Booster SCR, Booster seroconversion rate defined as percentage of subjects with pre-booster titer <1:28 and post-booster titer of ≥1:56, or pre-booster titer ≥1:28 and ≥4-fold post-booster; Primary vaccine strain, H5N1/A/Vietnam/1194/2004; heterologous booster strain H5N1/A/Indonesia/5/2005.