Cross-Institutional Evaluation of the Abbott ARCHITECT SARS-CoV-2 IgG Immunoassay

Objective To describe a cross-institutional approach to verify the Abbott ARCHITECT SARS-CoV-2 antibody assay and to document the kinetics of the serological response. Methods We conducted analytical performance evaluation studies using the Abbott ARCHITECT SARS-CoV-2 antibody assay on 5 Abbott ARCHITECT i2000 automated analyzers at 2 academic medical centers. Results Within-run and between-run coefficients of variance (CVs) for the antibody assay did not exceed 5.6% and 8.6%, respectively, for each institution. Quantitative and qualitative results agreed for lithium heparin plasma, EDTA-plasma and serum specimen types. Results for all SARS-CoV-2 IgG-positive and -negative specimens were concordant among analyzers except for 1 specimen at 1 institution. Qualitative and quantitative agreement was observed for specimens exchanged between institutions. All patients had detectable antibodies by day 10 from symptom onset and maintained seropositivity throughout specimen procurement. Conclusions The analytical performance characteristics of the Abbott ARCHITECT SARS-CoV-2 antibody assay within and between 2 academic medical center clinical laboratories were acceptable for widespread clinical-laboratory use.