Table 1 D57 antibody markera SARS-CoV-2 seroresponse rates and geometric means by COVID-19 outcome status.

From: Immune correlates analysis of a phase 3 trial of the AZD1222 (ChAdOx1 nCoV-19) vaccine

 

Post Day 57 COVID-19 Casesb

Non-Cases in Immunogenicity Subcohortc

Comparison

D57 Marker

N

Proportion with Antibody Responsed (95% CI)

Geometric Mean (GM) (95% CI)

N

Proportion with Antibody Responsed (95% CI)

Geometric Mean (GM) (95% CI)

Response Rate Difference (Non-Cases – Cases)

Ratio of GM (Non-Cases/ Cases)

Anti Spike IgG (BAU/ml)

33

97.0%

(80.0%, 99.6%)

100.3

(62.1, 162.1)

463

98.8%

(96.7%, 99.6%)

156.4

(139.2, 175.9)

1.9% (−1.5, 18.8%)

1.6 (0.95, 2.6)

Pseudovirus-nAb ID50 (IU50/ml)

22

72.7%

(49.3%, 88.0%)

8.4

(4.6, 15.5)

421

92.0%

(87.8%, 94.9%)

18.4

(15.5, 21.8)

19.3% (3.5, 42.9%)

2.2 (1.2, 4.2)

  1. aMedian (interquartile range) days from vaccination to D57 was 57 (2).
  2. bPost Day 57 cases are baseline SARS-CoV-2 negative vaccine recipients who received both planned vaccinations without any specified protocol deviations and were at risk at D57 and experienced symptomatic RT-PCR-confirmed COVID-19 starting 7 days post D57 visit through to the data cut (March 5, 2021) and were hence included in the D57 correlates analyses. “N” refers to the number of these cases (see Supplementary Fig. 3).
  3. cNon-cases are baseline negative vaccine recipients sampled into the immunogenicity subcohort with no evidence of SARS-CoV-2 infection (i.e., never tested RT-PCR positive) up to the end of the correlates study period (the data cut-off date March 5, 2021) and with D57 antibody data and hence were included in the D57 correlates analyses.
  4. dAntibody response defined by IgG concentration above the assay positivity cut-off (10.8424 BAU/ml) or by detectable ID50 > limit of detection (LOD) = 2.612 IU50/ml.
  5. Analysis based on baseline SARS-CoV-2 negative vaccine recipients in the Day 57 case-cohort set.
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