Table 2.
SARS-CoV-2 IgG binding antibody responses IgG serum antibody titers to vaccine (S-2P-WA-1 and Omicron B.1.1.529 strains) and reported as areas under the curve (AUC) via a 10-plex ECLIA assay.
| Group | 15 | 16 | 17 |
|---|---|---|---|
|
Primary EUA immunization Vaccine |
Janssen | Moderna | Pfizer/BioNTech |
| Ad26.COV2-S | mRNA-1273 | BNT162b2 | |
| 5 × 1010 vp | 100-mcg | 30-mcg | |
| Booster | Novavax (NVX-CoV2373) 5-mcg plus 50-mcg Matrix M | ||
| Vaccine (S-2P-WA-1) Strain | |||
| Day 1 GMTa (95% CI)b | 4123.0 | 18,310.7 | 14,083.8 |
| (2352.67–7225.51) | (11,647.69-28,785.21) | (9270.68-21,395.63) | |
| N = 20 | N = 16 | N = 31 | |
| Day 15 GMT (95% CI) | 22,969.7 | 50,130.9 | 44,295.7 |
| (15,905.3–33,171.7) | (44,100.3–56,986.2) | (39,894.3–49,182.7) | |
| N = 19 | N = 15 | N = 29 | |
| Day 29 GMT (95% CI) | 20,950.5 | 46,053.9 | 42,857.8 |
| (13,923.5–31,524.0) | (38,716.7–54,781.5) | (38,031.1–48,297.0) | |
| N = 18 | N = 14 | N = 29 | |
| Day 91 GMT (95% CI) | 15,093.62 | 44,220.6 | 38,321.0 |
| (9651.7–23,603.8) | (35,889.0–54,486.3) | (30,415.6–48,281.0) | |
| N = 19 | N = 13 | N = 25 | |
| Percentage with twofold rise at Day 15 (95% CI) | 84.2% | 60.0% | 62.1% |
| (60.4–96.6%) | (32.3–83.7%) | (42.3–79.3%) | |
| Geometric mean fold rise at Day 15 (95% CI) | 5.2 | 2.8 | 3.2 |
| (3.3–8.3) | (1.8–4.3) | (2.2–4.8) | |
| Omicron B.1.1.529 | |||
| Day 1 GMT (95% CI) | 535.5 | 3511.1 | 3269.6 |
| (277.0–1035.0) | (1750.2–7043.9) | (1828.8–5845.6) | |
| N = 20 | N = 16 | N = 31 | |
|
Day 15 GMT (95% CI) (n) |
5968.6 | 21,524.8 | 16,656.8 |
| (3459.4–10,297.6) | (15,803.9–29,316.7) | (13,114.4–21,156.1) | |
| N = 19 | N = 15 | N = 29 | |
|
Day 29 GMT (95% CI) (n) |
5164.3 | 17,202.8 | 15,484.3 |
| (2788.6-9564.0) | (1129.70–26,210.7) | (11,969.5–20,031.4) | |
| N = 18 | N = 14 | N = 29 | |
|
Day 91 GMT (95% CI) (n) |
3184.4 | 14,911.9 | 13,089.4 |
| (1790.0-5665.1) | (8938.6–24,877.0) | (8831.1–19,401.0) | |
| N = 19 | N = 13 | N = 25 | |
| GM fold decrease relative to WA-1 at Day 15 (95% CI) | 4.7 | 3.0 | 2.9 |
| (3.8–5.9) | (2.2–4.1) | (2.4–3.5) | |
| Day 15 geometric mean fold rise (95% CI) | 11.8 | 6.0 | 5.4 |
| (6.6–21.1) | (3.1–11.4) | (3.3–8.7) | |
Results are reported by primary immunization vaccine and timepoint relative to administration of the booster vaccine.
aGMT Geometric mean titers.
bCI Confidence intervals. The confidence intervals have not been adjusted for multiplicity, so the intervals should not be used to infer definitive treatment effects for secondary outcomes.