Table 5.
Immune responses by third dose vaccine allocation and priming vaccine schedule at 28 days post boost dose among the COVID-19-naive modified intention-to-treat population, group A
|
Prime with ChAd/ChAd |
Prime with BNT/BNT |
|||||||
|---|---|---|---|---|---|---|---|---|
| Control (n=93) | ChAd (n=100) | NVX (n=96) | NVX half (n=97) | Control (n=111) | ChAd (n=98) | NVX (n=103) | NVX half (n=99) | |
| SARS-CoV-2 anti-spike IgG, ELU/mL | ||||||||
| GMC* | 801 (664–967; n=91) | 2457 (2058–2933; n=99) | 6975 (5829–8347; n=95) | 4634 (3794–5660; n=97) | 2541 (2110–3060; n=111) | 13 424 (11 702–15 399; n=97) | 10 862 (9009–13 097; n=101) | 8550 (7210–10 138; n=98) |
| GMR† | Ref | 3·25 (2·52–4·20) | 8·75 (6·77–11·31) | 5·82 (4·50–7·51) | Ref | 5·33 (4·23–6·73) | 4·78 (3·80–6·02) | 3·07 (2·43–3·88) |
| Pseudotype virus neutralising antibody (wild-type), NT50 | ||||||||
| GMT* | 84·9 (68·7–105·0; n=90) | 193 (161–231; n=98) | 727 (598–883; n=87) | 470 (378–583; n=86) | 157 (129–192; n=111) | 950 (802–1126; n=98) | 766 (624–939; n=94) | 606 (495–743; n=89) |
| GMR† | Ref | 2·47 (1·96–3·11) | 8·86 (7·00–11·22) | 5·89 (4·64–7·46) | Ref | 6·01 (4·87–7·41) | 5·39 (4·35–6·67) | 3·50 (2·81–4·36) |
| Pseudotype virus neutralising antibody (delta), NT50 | ||||||||
| GMT* | 20·0 (15·6–25·7; n=91) | 48·9 (39·7–60·2; n=99) | 124 (99–156; n=84) | 87·2 (68·5–111; n=83) | 37·9 (30·5–47·1; n=111) | 260 (217–313; n=98) | 165 (131–209; n=89) | 131 (106–163; n=88) |
| GMR† | Ref | 2·58 (1·92–3·47) | 6·25 (4·60–8·50) | 4·40 (3·23–6·00) | Ref | 6·84 (5·39–8·68) | 4·94 (3·86–6·31) | 3·27 (2·55–4·20) |
| Live virus neutralising antibody, normalised NT80 | ||||||||
| GMT* | 146 (111–191; n=32) | 346 (263–454; n=31) | 837 (536–1307; n=18) | 713 (490–1038; n=20) | 531 (377–748; n=38) | 2614 (2075–3294; n=40) | 1454 (1060–1995; n=24) | 1792 (1261–2547; n=21) |
| GMR† | Ref | 2·57 (1·86–3·56) | 6·29 (4·22–9·37) | 5·30 (3·59–7·80) | Ref | 5·01 (3·59–7·01) | 2·65 (1·77–3·98) | 2·81 (1·85–4·26) |
| Cellular response (wild-type), spot forming cells per 106peripheral blood mononuclear cells | ||||||||
| GM* | 48·1 (35·0–66·3; n=45) | 53·0 (37·9–74·2; n=47) | 113·7 (78·7–164·2; n=46) | 98·4 (73·9–131·1; n=48) | 34·5 (23·8–50·0; n=53) | 95·8 (66·6–137·7; n=48) | 56·6 (37·2–86·2; n=49) | 35·3 (23·7–52·7; n=48) |
| GMR‡ | Ref | 1·08 (0·74–1·57) | 3·23 (2·20–4·76) | 2·43 (1·66–3·56) | Ref | 2·55 (1·64–3·96) | 1·79 (1·15–2·77) | 1·40 (0·89–2·18) |
| Cellular response (delta), spot forming cells per 106peripheral blood mononuclear cells | ||||||||
| GM* | 38·1 (27·0–54·0; n=45) | 44·9 (30·6–65·7; n=47) | 117·9 (85·5–162·7; n=46) | 86·3 (64·8–114·9; n=48) | 35·7 (25·1–50·9; n=53) | 108·0 (78·7–148·2; n=48) | 56·9 (37·9–85·4; n=49) | 41·6 (28·7–60·4; n=48) |
| GMR‡ | Ref | 1·13 (0·76–1·68) | 4·26 (2·84–6·39) | 2·71 (1·81–4·05) | Ref | 2·74 (1·85–4·05) | 1·71 (1·16–2·53) | 1·56 (1·05–2·33) |
| Cellular response (beta), spot forming cells per 106peripheral blood mononuclear cells | ||||||||
| GM* | 50·0 (36·1–69·0; n=45) | 53·0 (38·0–73·8; n=47) | 117·0 (82·8–165·4; n=46) | 91·1 (68·7–120·9; n=48) | 32·4 (22·4–46·9; n=53) | 101·2 (69·9–146·4; n=48) | 51·2 (34·7–75·4; n=49) | 37·2 (25·7–53·9; n=48) |
| GMR‡ | Ref | 1·03 (0·71–1·51) | 3·26 (2·21–4·81) | 2·20 (1·50–3·23) | Ref | 2·97 (1·95–4·51) | 1·78 (1·18–2·71) | 1·65 (1·08–2·52) |
ChAd=ChAdOx1 nCoV-19 vaccine, Oxford–AstraZeneca. BNT=BNT162b2 vaccine, Pfizer–BioNTech. Control=quadrivalent meningococcal conjugate vaccine. NVX=NVX-CoV2373 vaccine, Novavax. NVX half=half dose of NVX-CoV2373 vaccine. ELU=ELISA laboratory units. GMC=geometric mean concentration. GMR=geometric mean ratio. GM=geometric mean. GMT=geometric mean titre. NT50=50% neutralising antibody titre. NT80=80% neutralising antibody titre.
Data are GM (95% CI; number of samples available).
GMRs of the study vaccines were calculated by comparing to their corresponding controls in group A, B, or C, after adjusting for age group, site, baseline anti-spike IgG, interval between first and second dose, and interval between second and third dose; for primary endpoint of anti-spike IgG, 99% CIs were presented to account for multiple comparisons; for the secondary endpoints, 95% CIs were presented.
GMRs of the study vaccines were calculated by comparing to their corresponding controls in group A, B, or C, after adjusting for age group, site, baseline cellular response against wild-type, interval between first and second dose, and interval between second and third dose; 95% CIs were presented.