Background
Research is ongoing to establish the extent to which IgG antibodies to SARS-CoV-2, and in particular neutralizing antibodies, confer immunity to infection. The ability to longitudinally detect and quantitate antibodies which are associated with neutralization of the virus will become increasingly important as vaccines and therapeutics gain widespread use.1
A wide range of COVID-19 vaccines utilize strategies that generate antibody response to the spike protein and the RBD domain of the S1 subunit.2
Plasma from convalescent donors with neutralizing levels of specific IgG has shown some efficacy in limiting the consequences of COVID-19.3 Several studies have alluded to the potential of antibody testing, correlated to neutralizing antibody titers, as part of the evaluation of convalescent COVID plasma (CCP) to assess potency and efficacy of the product.4,5
Intended use6,7
The SARS-CoV-2 IgG II Quant assay is a chemiluminescent microparticle immunoassay (CMIA) used for the qualitative and quantitative determination of IgG antibodies to SARS-CoV-2 in human serum and plasma on the Alinity and ARCHITECT i Systems. The SARS-CoV-2 IgG II Quant assay is to be used as an aid in the diagnosis of SARS-CoV-2 infection in conjunction with clinical presentation and other laboratory tests.
The assay is also to be used as an aid in evaluating immune status of infected individuals andto monitor antibody response in individuals that have received the COVID-19 vaccine, by quantitatively measuring IgG antibodies against the spike receptor-binding domain (RBD) of SARS-CoV-2. Results from the SARS-CoV-2 IgG II Quant assay should not be used as thesole basis for diagnosis of SARS-CoV-2 infection.
Specific performance characteristics
Our highly sensitive and specific SARS-CoV-2 IgG II Quant assay (positive and negative percent agreement tables below) has demonstrated the ability to detect the spike RBD-based vaccine response (Pfizer-BioNTech COVID-19 cohort represented in the chart below) in longitudinal samples from individuals both with and without prior COVID-19 infection.
Positive agreement (post symptom onset)6
Negative agreement6,7
Sars-cov-2 igg ii quant assay response across time points6,7
Background
The presence of IgM antibodies allows for the identification of recent infection and evaluation of disease course. Accompanying an antibody test with an RNA test improves overall sensitivity of the viral diagnosis in the early stage of the infection.8
Intended use9,10
TheSARS-CoV-2 IgM assay is a chemiluminescent microparticle immunoassay (CMIA) used for the qualitative detection of IgM antibodies to SARS-CoV-2 in human serum and plasma on the Alinity i and ARCHITECT i Systems.
The SARS-CoV-2 IgM assay is to be used as an aid in the diagnosis of SARS-CoV-2 infection in conjunction with clinical presentation and other laboratory tests. Results from the SARS-CoV-2 IgM assay should not be used as the sole basis for diagnosis.
Clinical performance9,10
The positive agreement between the ARCHITECT i2000sr and the Alinity i was 100.00% and the negative agreement was 99.97%
aTwenty-eight (28) specimens from 8 immunocompromised patient were excluded from the study. Refer to the LIMITATIONS OF THE PROCEDURE section of this package insert for further information. When the results from these specimens were included, the PPA at ≤ 7 days post-symptom onset was 45.26% (95% CI: 35.63, 55.26), the PPA at 8 - 14 days post-symptom onset was 79.56% (95% CI: 72.05, 85.46), the PPA at 15 - 30 days post-symptom onset was 91.26% (95% CI: 84.22, 95.33), and the PPA at ≥ 31 days post-symptom onset was 94.74% (95% CI: 75.36, 99.73). bDuration of the IgM antibody response has not been fully characterized
Background
The persistence of immunoglobulin class G (IgG) antibodies allows identification of people who have been infected in the past, recovered from the illness, and possibly developed immunity.3 Therefore, SARS-CoV-2 IgG immunoassays play an important role in research and surveillance.11
Intended use12,13
The SARS-CoV-2 IgG assay is a chemiluminescent microparticle immunoassay (CMIA) used for the qualitative detection of IgG antibodies to SARS-CoV-2 in human serum and plasma on the Alinity i and ARCHITECT i Systems.
The SARS-CoV-2 IgG assay is to be used as an aid in the diagnosis of SARS-CoV-2 infection in conjunction with clinical presentation and other laboratory tests. Results from the SARS-CoV-2 IgG assay should not be used as the sole basis for diagnosis.
Clinical performance12,13
The positive agreement between the ARCHITECTi2000SR and the Alinity i was 100% and the negative agreement was 99.00%.
aFive specimens from 1 immunocompromised patient were excluded from the study. Refer to the LIMITATIONS OF THE PROCEDURE section of the package insert for further information. When the results from these specimens were included, the PPA at ≥ 14 days post-symptom onset was 96.77% (95% CI: 90.86, 99.33).
