Table 3.
Geometric mean concentrations (GMCs) at day 0 and 28 and geometric mean-fold rises (GMFRs) and seroresponse rates (SRRs)a for anti-spike IgG antibodies against the prototype and five variant SARS-CoV-2 viruses.
| ChAdOx1-S full dose |
ChAdOx1-S half dose |
BNT162b2 half dose |
|||
|---|---|---|---|---|---|
| Prototype virus | Day 0 | N = 231 | N = 236 | N = 234 | |
|
GMC AU/mL (95% CI) |
32966 (28927, 37569) |
34111 (29948, 38853) |
31685 (27475, 36542) |
||
| Day 28 | N = 204 | N = 214 | N = 219 | ||
|
GMC AU/mL (95% CI) |
118348 (109045, 128444) |
104465 (95962, 113721) |
235395 (215466, 257168) |
||
|
GMFR (95% CI) |
3.39 (2.92, 3.94) |
2.99 (2.57, 3.48) |
7.42 (6.39, 8.60) |
||
|
SRR (95% CI) |
34.3 (27.8, 41.3) |
27.1 (21.3, 33.6) |
71.2 (64.7, 77.1) |
||
| Alpha (B.1.1.7) | Day 0 |
GMC AU/mL (95% CI) |
31525 (27657, 35935) |
32252 (28260, 36809) |
29794 (25884, 34294) |
| Day 28 |
GMC AU/mL (95% CI) |
103369 (95322, 112095) |
91550 (84074, 99692) |
193286 (176656, 211480) |
|
|
GMFR (95% CI) |
3.09 (2.67, 3.59) |
2.77 (2.39, 3.23) |
6.49 (5.61, 7.51) |
||
|
SRR (95% CI) |
29.9 (23.7, 36.7) |
25.2 (19.6, 31.6) |
60.7 (53.9, 67.2) |
||
| Beta (B.1.351) | Day 0 |
GMC AU/mL (95% CI) |
26751 (23440, 30529) |
27009 (23660, 30831) |
24737 (21341, 28672) |
| Day 28 |
GMC AU/mL (95% CI) |
88241 (81175, 95922) |
78182 (71454, 85545) |
177004 (161041, 194549) |
|
|
GMFR (95% CI) |
3.12 (2.69, 3.63) |
2.83 (2.43, 3.29) |
7.17 (6.15, 8.36) |
||
|
SRR (95% CI) |
29.4 (23.3, 36.2) |
27.1 (21.3, 33.6) |
65.3 (58.6, 71.6) |
||
| Delta (B.1.617.2) | Day 0 |
GMC AU/mL (95% CI) |
23338 (20440, 26647) |
23572 (20751, 26776) |
21781 (18892, 25112) |
| Day 28 |
GMC AU/mL (95% CI) |
82478 (75904, 89622) |
72092 (66130, 78592) |
184988 (169370, 202046) |
|
|
GMFR (95% CI) |
3.32 (2.85, 3.87) |
3.01 (2.59, 3.50) |
8.56 (7.35, 9.97) |
||
|
SRR (95% CI) |
31.9 (25.5, 38.7) |
27.6 (21.7, 34.1) |
78.5 (72.5, 83.8) |
||
| Gamma (P.1) | Day 0 |
GMC AU/mL (95% CI) |
28963 (25380, 33051) |
29708 (26026, 33911) |
26894 (23129, 31272) |
| Day 28 |
GMC AU/mL (95% CI) |
105106 (96237, 114793) |
92524 (84587, 101206) |
209653 (190385, 230871) |
|
|
GMFR (95% CI) |
3.44 (2.96, 4.00) |
3.03 (2.61, 3.52) |
7.80 (6.70, 9.08) |
||
|
SRR (95% CI) |
33.8 (27.4, 40.8) |
28.0 (22.1, 34.6) |
75.3 (69.1, 80.9) |
||
| D614G | Day 0 |
GMC AU/mL (95% CI) |
38792 (34054, 44188) |
40009 (35203, 45470) |
37183 (32279, 42831) |
| Day 28 |
GMC AU/mL (95% CI) |
134873 (124357, 146278) |
119319 (109754, 129717) |
272820 (250067, 297643) |
|
|
GMFR (95% CI) |
3.29 (2.83, 3.82) |
2.92 2.51, 3.38) |
7.33 (6.33, 8.50) |
||
|
SRR (95% CI) |
32.8 (26.4, 39.7) |
26.6 (20.8, 33.1) |
70.3 (63.8, 76.3) |
a: Seroresponse defined as ≥ 4-fold increase in titer at day 28 compared with day 0 in those seropositive at baseline; or the presence of antibodies at day 28 in those who were seronegative at baseline.
b: Numbers of participants with available anti-spike IgG antibody data for the five variants are the same as those shown for the prototype virus.