Table 2.
Immune Response Stratified by HIV Treatment for Adjuvanted and Nonadjuvanted Vaccine, Hemagglutination Antibodies Against A/California/7/2009 (H1N1v)
| AS03A adjuvanted H1N1v vaccine (3.75 μg HA) |
Nonadjuvanted H1N1v vaccine (15 μg HA) |
|||||
| Variable | With HAART | Without HAART | All | With HAART | Without HAART | All |
| Prevaccination at day 0 | ||||||
| No. of patients tested | 120 | 35 | 155 | 116 | 34 | 150 |
| Geometric mean titer (95% CI) | 9.2 (7.7–10.9) | 6.4 (5.3–7.7) | 8.5 (7.3–9.8) | 8.6 (7.3–10.0) | 6.7 (5.4–8.4) | 8.1 (7.1–9.2) |
| No. (%) of patients with HI titers ≥ 1:40 (95% CI) | 12 (10.0)(5.3–16.8) | 0 (0.0)(0.0–.1) | 12 (7.7)(4.1–13.1) | 13 (11.2)(6.1–18.4) | 2 (5.9)(0.7–19.7) | 15 (10.0)(5.7–16.0) |
| Post–dose 1 at day 21 | ||||||
| No. of patients tested | 117 | 35 | 152 | 114 | 33 | 147 |
| Geometric mean titer (95% CI) | 189.4 (151.1–236.8) | 175.0 (118.6–258.2) | 186.0 (154.0–224.7) | 102.8 (77.8–137.2) | 201.6 (135.7–323.9) | 119.6 (94.0–152.1) |
| No. (%) of patients with HI titers ≥ 1:40 (95% CI) | 109 (93.2)(87.0–97.0) | 33 (94.3)(80.8–99.3) | 142 (93.4)(88.2–96.8) | 80 (70.2)(60.9–78.4) | 31 (93.9)(79.8–99.3) | 111 (75.5)(67.7–82.2) |
| Seroconversion rate, no. (%) of patients (95% CI) | 103 (88.0)(80.7–93.3) | 32 (91.4)(76.9–98.2) | 135 (88.8)(82.7–93.4) | 74 (65.5)(56.0–74.2) | 30 (90.9)(75.7–98.1) | 104 (71.2)(63.2–78.4) |
| Seroconversion factor (95% CI) | 20.5 (16.3–26.0) | 27.3 (18.7–40.0) | 21.9 (18.0–26.8) | 12.4 (9.4–16.2) | 29.7 (19.9–44.5) | 15.1 (11.9–19.0) |
| Post–dose 2 at day 42 | ||||||
| No. of patients tested | 108 | 35 | 143 | 108 | 31 | 139 |
| Geometric mean titer (95% CI) | 424.4 (358.3–502.7) | 275.7 (203.8–373.0) | 381.9 (329.0–443.3) | 164.1 (131.4–205.0) | 197.8 (141.1–277.3) | 171.1 (141.9–206.3) |
| No. (%) of patients with HI titers ≥ 1:40 (95% CI) | 107 (99.1)(95.0–100.0) | 34 (97.1)(85.1–99.9) | 141 (98.6)(95.0–99.8) | 98 (90.7)(83.6–95.5) | 30 (96.8)(83.3–99.9) | 128 (92.1)(86.3–96.0) |
| Seroconversion rate, no. (%) of patients (95% CI) | 104 (96.3)(90.8–99.0) | 34 (97.1)(85.1–99.9) | 138 (96.5)(92.0–98.9) | 92 (85.2)(77.1–91.3) | 29 (93.6)(78.6–99.2) | 121 (87.1)(80.3–92.1) |
| Seroconversion factor (95% CI) | 46.3 (36.6–58.6) | 43.1 (31.6–58.8) | 45.5 (37.6–55.1) | 19.5 (15.5–24.5) | 28.6 (20.9–39.2) | 21.2 (17.5–25.7) |
NOTE. Seroconversion rate is given as the percentage of patients with a prevaccination HI titer <1:10 and a post-vaccination titer ≥ 1:40, or showing a significant increase in antibody titer defined as a prevaccination titer ≥ 1:10 and at least a 4-fold increase in post-vaccination titer. Seroconversion factor or geometric mean fold increase is defined as the geometric mean of the within-subject ratios of the post-vaccination reciprocal HI titer to the day 0 reciprocal HI titer. According to the European Union Committee for Medicinal Products for Human Use, criteria for HI antibody response in adults 18–60 years of age are a percentage of HI titers ≥ 1:40 > 70%, a percentage of seroconversion >40%, and a geometric mean fold increase > 2.5. According to the United States Center for Biologics Evaluation and Research, criteria for HI antibody response in adults <65 years of age are a lower limit of the 95% CI for HI titers ≥ 1:40 ≥ 70% and a lower limit of the 95% CI for seroconversion ≥ 40%. CI, confidence interval; HA, hemagglutinin; HI, hemagglutination inhibition.