Table 4.
Specific antibody responses to RBD, neutralising antibodies to live SARS-CV-2 and pseudovirus post vaccination in phase 1 trial
| Adult group | Elderly group | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Low dose (0, 28 days n = 24) | High dose (0, 28 days n = 24) | High dose (0, 14, 28 days n = 24) | Placebo (n = 24) | p value | Low dose (0, 28 days n = 18) | High dose (0, 28 days n = 18) | High dose (0, 14, 28 days n = 18) | Placebo (n = 18) | p value | |
| Day 0 | ||||||||||
| ELISA antibodies to the receptor binding domain | ||||||||||
| GMT | 20.0 (20.0–20.0) | 20.9 (19.1–22.8) | 20.8 (19.2–22.5) | 20.0 (20.0–20.0) | 0.57 | 20.0 (20.0–20.0) | 20.0 (20.0–20.0) | 20.0 (20.0–20.0) | 20.0 (20.0–20.0) | – |
| Neutralising antibodies to live SARS-CoV-2 | ||||||||||
| GMT | 0.7 (0.7–0.7) | 0.7 (0.7–0.7) | 0.7 (0.7–0.7) | 0.7 (0.7–0.7) | – | 0.7 (0.7–0.7) | 0.7 (0.7–0.7) | 0.7 (0.7–0.7) | 0.7 (0.7–0.7) | – |
| Neutralising antibodies to pseudovirus | ||||||||||
| GMT | 17.2 (14.7–20.1) | 16.0 (14.0–18.2) | 16.1 (14.5–17.9) | 15.5 (14.5–16.6) | 0.64 | 15.7 (14.3–17.2) | 15.0 (15.0–15.0) | 15.0 (15.0–15.0) | 15.0 (15.0–15.0) | 0.40 |
| Day 7 | ||||||||||
| ELISA antibodies to the receptor binding domain | ||||||||||
| GMT | 21.0 (19.0–23.1) | 23.2 (19.6–27.5) | 402.6 (221.3–732.7) | 20.0 (20.0–20.0) | <0.001 | 24.0 (16.3–35.3) | 21.3 (18.7–24.2) | 101.2 (40.8–250.7) | 20.0 (20.0–20.0) | <0.001 |
| Seroconversion | 0 (0%) | 0 (0%) | 22 (92%) | 0 (0%) | <0.001 | 1 (6%) | 0 (0%) | 9 (50%) | 0 (0%) | <0.001 |
| Neutralising antibodies to live SARS-CoV-2 | ||||||||||
| GMT | 0.8 (0.7–1.0) | 0.9 (0.8–1.2) | 19.4 (11.7–32.2) | 0.7 (0.7–0.7) | <0.001 | 0.8 (0.7–1.0) | 1.0 (0.8–1.3) | 4.5 (2.2–9.0) | 0.7 (0.7–0.7) | <0.001 |
| Seroconversion | 0 (0%) | 0 (0%) | 23 (96%) | 0 (0%) | <0.001 | 0 (0%) | 0 (0%) | 11 (61%) | 0 (0%) | <0.001 |
| Neutralising antibodies to pseudovirus | ||||||||||
| GMT | 17.6 (14.6–21.2) | 19.7 (15.9–24.5) | 82.1 (56.0–120.5) | 15.0 (15.0–15.0) | <0.001 | 16.9 (14.2–20.1) | 16.1 (13.9–18.5) | 21.9 (16.4–29.4) | 15.0 (15.0–15.0) | 0.018 |
| Seroconversion | 3 (13%) | 6 (25%) | 21 (88%) | 0 (0%) | <0.001 | 2 (11%) | 1 (6%) | 6 (33%) | 0 (0%) | 0.023 |
| Day 14 | ||||||||||
| ELISA antibodies to the receptor binding domain | ||||||||||
| GMT | 31.3 (21.9–44.7) | 62.7 (37.5–104.8) | 1348.8 (654.5–2779.5) | 20.0 (20.0–20.0) | <0.001 | 34.1 (19.2–60.8) | 25.3 (19.3–33.2) | 268.7 (113.9–634.2) | 20.0 (20.0–20.0) | <0.001 |
| Seroconversion | 5 (21%) | 10 (42%) | 22 (92%) | 0 (0%) | <0.001 | 3 (17%) | 2 (11%) | 14 (78%) | 0 (0%) | <0.001 |
| Neutralising antibodies to live SARS-CoV-2 | ||||||||||
| GMT | 1.0 (0.8–1.3) | 1.5 (1.0–2.2) | 28.2 (17.5–45.4) | 0.7 (0.7–0.7) | <0.001 | 0.9 (0.7–1.2) | 1.0 (0.8–1.4) | 7.1 (3.2–15.7) | 0.7 (0.7–0.7) | <0.001 |
| Seroconversion | 1 (4%) | 3 (13%) | 23 (96%) | 0 (0%) | <0.001 | 0 (0%) | 0 (0%) | 12 (67%) | 0 (0%) | <0.001 |
| Neutralising antibodies to pseudovirus | ||||||||||
| GMT | 17.0 (14.7–19.6) | 18.6 (15.0–23.0) | 86.7 (58.7–128.0) | 15.5 (14.5–16.5) | <0.001 | 15.7 (14.2–17.4) | 21.9 (16.6–29.1) | 25.6 (19.6–33.5) | 15.7 (14.2–17.4) | <0.001 |
| Seroconversion | 3 (13%) | 4 (17%) | 23 (96%) | 1 (4%) | <0.001 | 1 (6%) | 6 (33%) | 10 (56%) | 1 (6%) | <0.001 |
| Day 28 | ||||||||||
| ELISA antibodies to the receptor binding domain | ||||||||||
| GMT | 39.3 (25.2–61.2) | 96.9 (55.4–169.4) | 1282.1 (713.6–2303.4) | 20.0 (20.0–20.0) | <0.001 | 42.9 (20.1–91.6) | 45.1 (26.8–76.0) | 548.2 (198.2–1516.6) | 21.7 (18.2–25.9) | <0.001 |
| Seroconversion | 7 (29%) | 14 (58%) | 23 (96%) | 0 (0%) | <0.001 | 5 (28%) | 5 (28%) | 14 (78%) | 1 (6%) | <0.001 |
| Neutralising antibodies to live SARS-CoV-2 | ||||||||||
| GMT | 1.2 (0.9–1.6) | 2.3 (1.5–3.3) | 102.9 (61.9–171.2) | 0.7 (0.7–0.7) | <0.001 | 1.0 (0.8–1.2) | 1.5 (1.1–2.0) | 22.4 (7.7–65.5) | 0.7 (0.7–0.7) | <0.001 |
| Seroconversion | 1 (4%) | 7 (29%) | 24 (100%) | 0 (0%) | <0.001 | 0 (0%) | 1 (6%) | 14 (78%) | 0 (0%) | <0.001 |
| Neutralising antibodies to pseudovirus | ||||||||||
| GMT | 26.5 (19.8–35.5) | 29.0 (21.5–39.1) | 108.0 (78.8–148.2) | 15.5 (14.4–16.7) | <0.001 | 19.4 (15.7–24.0) | 25.7 (19.4–34.2) | 50.5 (36.3–70.1) | 16.5 (13.5–20.1) | <0.001 |
| Seroconversion | 10 (42%) | 12 (50%) | 23 (96%) | 1 (4%) | <0.001 | 5 (28%) | 9 (50%) | 15 (83%) | 1 (6%) | <0.001 |