Table 2. Immunogenicity of Intanza 9 μg and the IM reference vaccine (Vaxigrip) in adults 18 to 59 y of age.
| Study | Measure | Strain A/H1N1 |
Strain A/H3N2 |
Strain B |
|||
|---|---|---|---|---|---|---|---|
| ID 9 μg | IM 15 μg | ID 9 μg | IM 15 μg | ID 9 μg | IM 15 μg | ||
|
NCT00703651 (Year 3) |
Seroprotection (%) |
90.7 [83.6;95.5] |
91.3 [84.2;96.0] |
100.0 [96.6;100.0] |
99.0 [94.8;100.0] |
83.3 [74.9;89.8] |
81.4 [72.4;88.4] |
| Seroconversion (%) |
14.8 [8.7;22.9] |
18.3 [11.4;27.1] |
60.2 [50.3;69.5] |
45.2 [35.4;55.3] |
24.1 [16.4;33.3] |
19.6 [12.4;28.6] |
|
| GMT ratio |
2.0 [1.7;2.4] |
2.1 [1.7;2.5] |
4.6 [3.8;5.6] |
3.5 [2.8;4.4] |
2.3 [1.9;2.7] |
2.3 [1.9;2.8] |
|
|
NCT00258934 |
Seroprotection (%) |
92.4% [89.3;94.9] |
88.8% [85.3;91.8] |
99.7% [98.6;100.0] |
98.7% [97.0;99.6] |
90.6% [87.2;93.3] |
85.5% [81.5;88.8] |
| Seroconversion (%) |
74.3% [69.7;78.7] |
70.4% [65.6;74.9] |
85.1% [81.2;88.5] |
79.2% [74.8;83.1] |
76.4% [71.9;80.6] |
73.5% [68.8;77.8] |
|
| GMT ratio |
16.2 [13.7;19.2] |
13.8 [11.6;16.4] |
28.2 [23.7;33.5] |
20.7 [17.5;24.4] |
12.1 [10.5;13.8] |
10.84 [9.56;12.29] |
|
| NCT00383539 | Seroprotection (%) |
87.2 [85.2;89.0] |
86.2 [82.6;89.3] |
93.5 [92.0;94.8] |
95.4 [93.0;97.2] |
72.9 [70.4;75.3] |
74.8 [70.4;78.8] |
| Seroconversion (%) |
57.5 [54.7;60.2] |
56.4 [51.6;61.1] |
66.5 [63.8;69.0] |
69.3 [64.7;73.6] |
56.7 [54.0;59.4] |
60.8 [56.0;65.4] |
|
| GMT ratio | 9.17 [8.33;10.1] | 9.71 [8.19;11.5] | 11.5 [10.4;12.7] | 11.2 [9.58;13.1] | 6.39 [5.96;6.84] | 6.63 [5.90;7.46] | |
Values are means with 95% confidence intervals in brackets. As described in the CPMP Note for Guidance,54 seroprotection was defined as a HI titer ≥ 40, seroconversion as a post-vaccination HI titer ≥ 40 in seronegative subjects or a ≥ 4-fold increase in HI titer, and GMT ratio as the ratio of post-vaccination HI GMT to pre-vaccination HI GMT. GMT, geometric mean titer.