Table 2.
Summary of immunogenicity for the per-protocol cohort
| Treatment groupa | |||||
|---|---|---|---|---|---|
|
Vaccine Strain |
|
QIV |
LD QIV-AS |
LD TIV-AS |
TIV |
| Nb |
|
104 |
104 |
104 |
105 |
| A/Solomon Islands |
|
|
|
|
|
| GMT (95% CI) |
Pre |
21.4 (16.1–28.4) |
22.2 (16.6–29.5) |
23.3 (17.5–31.0) |
18.4 (14.3–23.7) |
| |
Post |
130.0 (106.1–159.4) |
150.6 (118.4–191.5) |
160.4 (129.1–199.3) |
133.8 (105.6–169.7) |
| SCR %(95% CI) |
Post |
56.7 (46.7–66.4)*$ |
57.7 (47.6–67.3)* $ |
54.8 (44.7–64.6)* $ |
60.0 (50.0–69.4)* $ |
| SPR %(95% CI) |
Pre |
37.5 (28.2–47.5) |
42.3 (32.7–52.4) |
40.4 (30.9–50.5) |
35.2 (26.2–45.2) |
| |
Post |
92.3 (85.4–96.6)* $ |
88.5 (80.7–93.9)* $ |
93.3 (86.6–97.3)* $ |
90.5 (83.2–95.3)* $ |
| SCF (95% CI) |
Post |
6.1 (4.6–8.0)* |
6.8 (5.0–9.2)* |
6.9 (5.0–9.4)* |
7.3 (5.3–9.9)* |
| A/Wisconsin |
|
|
|
|
|
| GMT (95% CI) |
Pre |
29.3 (23.0–37.3) |
25.7 (19.8–33.3) |
30.7 (23.7–39.8) |
29.0 (22.5–37.4) |
| |
Post |
162.1 (138.0–190.4) |
189.5 (158.9–226.0) |
197.9 (169.1–231.7) |
156.3 (127.5–191.6) |
| SCR %(95% CI) |
Post |
60.6 (50.5–70.0)* $ |
66.3 (56.4–75.3)* $ |
64.4 (54.4–73.6)* $ |
59.0 (49.0–68.5)* $ |
| SPR %(95% CI) |
Pre |
51.0 (41.0–60.9) |
46.2 (36.3–56.2) |
53.8 (43.8–63.7) |
55.2 (45.2–65.0) |
| |
Post |
97.1 (91.8–99.4)* $ |
98.1 (93.2–99.8)* $ |
100 (96.5–100)* $ |
96.2 (90.5–99.0)* $ |
| SCF (95% CI) |
Post |
5.5 (4.4–6.9)* |
7.4 (5.8–9.4)* |
6.4 (5.0–8.3)* |
5.4 (4.1–7.0)* |
| B/Malaysia |
|
|
|
|
|
| GMT (95% CI) |
Pre |
32.2 (24.8–41.8) |
26.6 (20.2–35.0) |
23.2 (17.7–30.4) |
27.2 (20.6–35.8) |
| |
Post |
192.8 (159.6–232.9) |
213.0 (174.0–260.9) |
187.0 (151.9–230.3) |
188.5 (150.0–237.0) |
| SCR %(95% CI) |
Post |
57.7 (47.6–67.3)* $ |
65.4 (55.4–74.4)* $ |
56.7 (46.7–66.4)* $ |
59.0 (49.0–68.5)* $ |
| SPR %(95% CI) |
Pre |
51.0 (41.0–60.9) |
47.1 (37.2–57.2) |
42.3 (32.7–52.4) |
44.8 (35.0–54.8) |
| |
Post |
97.1 (91.8–99.4)* $ |
97.1 (91.8–99.4)* $ |
96.2 (90.4–98.9)* $ |
93.3 (86.7–97.3)* $ |
| SCF (95% CI) |
Post |
6.0 (4.7–7.7)* |
8.0 (6.1–10.5)* |
8.1 (5.9–11.0)* |
6.9 (5.2–9.3)* |
| B/Jiangsu |
|
|
|
|
|
| GMT (95% CI) |
Pre |
19.6 (15.6–24.8) |
19.5 (15.4–24.5) |
23.4 (18.3–29.7) |
19.2 (15.2–24.3) |
| |
Post |
179.1 (151.4–211.9) |
158.3 (130.7–191.9) |
59.2 (47.3–74.0) |
43.4 (34.5–54.6) |
| SCR %(95% CI) |
Post |
76.0 (66.6–83.8)* $ |
78.8 (69.7–86.2)* $ |
26.9 (18.7–36.5) |
19.0 (12.0–27.9) |
| SPR %(95% CI) |
Pre |
31.7 (22.9–41.6) |
38.5 (29.1–48.5) |
43.3 (33.6–53.3) |
39.0 (29.7–49.1) |
| |
Post |
98.1 (93.2–99.8)* $ |
95.2 (89.1–98.4)* $ |
75.0 (65.6–83.0)* |
63.8 (53.9–73.0) |
| SCF (95% CI) | Post | 9.1 (7.2–11.5)* | 8.1 (6.6–10.0)* | 2.5 (2.1–3.0)* | 2.3 (1.9–2.6) |
a Groups were administered the quadrivalent influenza vaccine (QIV), the low-dose adjuvanted quadrivalent influenza vaccine (LD QIV-AS), the low-dose adjuvanted trivalent influenza vaccine (LD TIV-AS) or the trivalent influenza vaccine (TIV).
b Abbreviations: 95% CI = 95% confidence interval (lower limit–upper limit); GMT = geometric mean titer; N = total number of participants; Pre = Pre-vaccination (Day 0); Post = Post-vaccination (Day 21); SCR = Seroconversion ratio defined as percentage of participants with antibody titer ≥1:40 1/DIL post-vaccination for initially seronegative participants, or ≥4 fold the pre-vaccination antibody titer for initially seropositive participants; SPR = Seroprotection rate defined as percentage of participants with antibody titer ≥1:40; SCF = Seroconversion factor defined as the fold increase in GMTs post-vaccination compared with pre-vaccination.
* CHMP criteria were met or exceeded (SCR > 40%, SPR > 70%, SCF > 2.5).
$ CBER criteria were met or exceeded (95% CI lower limit for SCR ≥ 40%, SPR ≥ 70%).