The Comparability of Anti-Spike SARS-CoV-2 Antibody Tests is Time-Dependent: a Prospective Observational Study
Thomas Perkmann, Patrick Mucher, Nicole Perkmann‐Nagele, Astrid Radakovics, Manuela Repl, Thomas Köller, Klaus G. Schmetterer, Johannes W. Bigenzahn, Florentina Leitner, Galateja Jordakieva, Oswald Wagner, Christoph J. Binder, Helmuth Haslacher
Abstract
This work showed that the comparability of apparently standardized SARS-CoV-2 antibody assays (Roche, Abbott; both given in BAU/mL) after vaccination depends on the time of blood withdrawal. Initially (3 weeks after the first dose AZD1222), there were 3 times higher values in the Abbott assay, but this relationship inversed before boosting (11 weeks after the first dose) with Roche 2 times greater than Abbott. After the booster, Roche quantified ca. 5 times higher levels than Abbott. This must be considered by clinicians when interpreting SARS-CoV-2 antibody levels.