Journal
NATURE MEDICINE
Volume 27, Issue 11, Pages 2032-+Publisher
NATURE PORTFOLIO
DOI: 10.1038/s41591-021-01540-1
Keywords
-
Funding
- UK Research and Innovation [MC_PC_19055]
- Engineering and Physical Sciences Research Council [EP/R013756/1]
- National Institute for Health Research [COV19 OxfordVacc-01]
- Coalition for Epidemic Preparedness Innovations
- National Institute for Health Research Oxford Biomedical Research Centre (BRC4 Vaccines Theme)
- Thames Valley and South Midland's NIHR Clinical Research Network
- AstraZeneca
Ask authors/readers for more resources
Defined levels of SARS-CoV-2-specific binding and neutralizing antibodies elicited by the COVID-19 vaccine were identified as correlates of protection against symptomatic infection. Higher levels of immune markers were correlated with a reduced risk of symptomatic infection. The data can be used to extrapolate efficacy estimates to new populations.
Defined levels of SARS-CoV-2-specific binding and neutralizing antibodies elicited by the COVID-19 vaccine ChAdOx1 nCoV-19 are identified as correlates of protection against symptomatic infection. The global supply of COVID-19 vaccines remains limited. An understanding of the immune response that is predictive of protection could facilitate rapid licensure of new vaccines. Data from a randomized efficacy trial of the ChAdOx1 nCoV-19 (AZD1222) vaccine in the United Kingdom was analyzed to determine the antibody levels associated with protection against SARS-CoV-2. Binding and neutralizing antibodies at 28 days after the second dose were measured in infected and noninfected vaccine recipients. Higher levels of all immune markers were correlated with a reduced risk of symptomatic infection. A vaccine efficacy of 80% against symptomatic infection with majority Alpha (B.1.1.7) variant of SARS-CoV-2 was achieved with 264 (95% CI: 108, 806) binding antibody units (BAU)/ml: and 506 (95% CI: 135, not computed (beyond data range) (NC)) BAU/ml for anti-spike and anti-RBD antibodies, and 26 (95% CI: NC, NC) international unit (IU)/ml and 247 (95% CI: 101, NC) normalized neutralization titers (NF50) for pseudovirus and live-virus neutralization, respectively. Immune markers were not correlated with asymptomatic infections at the 5% significance level. These data can be used to bridge to new populations using validated assays, and allow extrapolation of efficacy estimates to new COVID-19 vaccines.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available