Table 2.
Anti-HBs seroprotection rates and antibody GMCs following HepB booster vaccination at 4 years post-primary in participants who previously received primary vaccination with RTS,S/AS01E or HepB (ATP cohort for immunogenicity).
| Group | Timing | N | % (95% CI) ≥ 6.2 mIU/mL |
% (95% CI) ≥ 10 mIU/mL |
% (95% CI) ≥ 100 mIU/mL |
GMC, mIU/mL (95% CI) |
|---|---|---|---|---|---|---|
| RTS,S | Pre-vaccination | 398 | 20.9 (17.0; 25.2) | 15.8 (12.4; 19.8) | 4.3 (2.5; 6.8) | 5.0 (4.5; 5.7) |
| 1 month post-dose 3 | 397 | 100 (99.1; 100) | 100 (99.1; 100) | 100 (99.1; 100) | 6412.7 (5732.9; 7173.0) | |
| 12 months post-dose 3 | 380 | 100 (99.0; 100) | 100 (99.0; 100) | 98.9 (97.3; 99.7) | 1995.0 (1784.5; 2230.5) | |
| 24 months post-dose 3 | 365 | 100 (99.0; 100) | 100 (99.0; 100) | 96.4 (94.0; 98.1) | 1540.4 (1345.1; 1764.1) | |
| 36 months post-dose 3 | 355 | 99.7 (98.4; 100) | 99.4 (98.0; 99.9) | 94.9 (92.1; 97.0) | 896.6 (780.2;1030.3) | |
| 48 months post-dose 3 | 361 | 99.4 (98.0; 99.9) | 99.4 (98.0; 99.9) | 92.0 (88.7; 94.6) | 669.8 (579.7; 773.9) | |
| 1 month post-booster HepB | 362 | 100 (99.0; 100) | 100 (99.0; 100) | 99.4 (98.0; 99.9) | 46634.7 (40561.3; 53617.6) | |
| Control | Pre-vaccination | 251 | 22.7 (17.7; 28.4) | 17.9 (13.4; 23.2) | 5.6 (3.1; 9.2) | 5.4 (4.7; 6.4) |
| 1 month post-dose 3 | 253 | 97.2 (94.4; 98.9) | 96.0 (92.9; 98.1) | 83.4 (78.2; 87.8) | 377.4 (310.6; 458.7) | |
| 12 months post-dose 3 | 241 | 94.6 (91.0; 97.1) | 92.9 (88.9; 95.8) | 63.5 (57.1; 69.6) | 127.7 (105.0; 155.4) | |
| 24 months post-dose 3 | 235 | 88.5 (83.7; 92.3) | 83.8 (78.5; 88.3) | 46.4 (39.9; 53.0) | 69.8 (56.1; 86.9) | |
| 36 months post-dose 3 | 230 | 83.0 (77.6; 87.7) | 77.4 (71.4; 82.6) | 31.3 (25.4; 37.7) | 40.0 (32.2; 49.7) | |
| 48 months post-dose 3 | 233 | 79.4 (73.6; 84.4) | 73.8 (67.7; 79.3) | 24.0 (18.7; 30.0) | 30.8 (24.9; 38.1) | |
| 1 month post-booster HepB | 229 | 98.3 (95.6; 99.5) | 98.3 (95.6; 99.5) | 95.6 (92.1; 97.9) | 9258.2 (6925.3; 12377.0) |
ATP, according-to-protocol; CI, confidence interval; FU, follow-up; GMC, geometric mean antibody concentration; HepB, hepatitis B vaccine; IU, international unit; M, month; N, total number of participants; %, percentage of participants with antibody concentrations above the specified cutoff; RTS,S/AS01E, malaria vaccine. RTS,S groups, all study groups who received primary vaccination with RTS,S/AS01E; control, all study groups who received primary vaccination with HepB; post-dose 3, blood sampling after the third dose, x months after primary vaccination course; post-booster HepB, blood sampling 1 month after HepB booster dose.