Elecsys Anti‑SARS‑CoV‑2 S for use on the cobas e analyzers is an electrochemiluminescence immunoassay intended for qualitative and semi-quantitative detection of antibodies to SARS‑CoV‑2 in human serum and plasma (lithium heparin, dipotassium-EDTA, tripotassium-EDTA, and sodium citrate). The Elecsys Anti‑SARS‑CoV‑2 S assay is intended for use as an aid in identifying individuals with an adaptive immune response to SARS‑CoV‑2, indicating recent or prior infection. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity. The Elecsys Anti‑SARS‑CoV‑2 S assay should not be used to diagnose or exclude acute SARS‑CoV‑2 infection.
Testing is limited to laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. 263a, that meet requirements to perform moderate or high complexity tests.

Results are for the detection of SARS‑CoV‑2 antibodies. Antibodies to SARS‑CoV‑2 are generally detectable in blood several days after initial infection, although the duration of time antibodies are present post-infection is not well characterized. Individuals may have detectable virus present for several weeks following seroconversion.

Laboratories within the United States and its territories are required to report all results to the appropriate public health authorities. The sensitivity of the Elecsys Anti‑SARS‑CoV‑2 S assay early after infection is unknown. Negative results do not preclude acute SARS‑CoV‑2 infection. If acute infection is suspected, direct testing for SARS‑CoV‑2 is necessary.

False positive results for Elecsys Anti‑SARS‑CoV‑2 S assay may occur due to cross-reactivity from pre‑existing antibodies or other possible causes.

The Elecsys Anti‑SARS‑CoV‑2 S assay is only for use under the Food and Drug Administration’s Emergency Use Authorization.

The electrochemiluminescence immunoassay “ECLIA” is intended for use on cobas e immunoassay analyzers.

Double-antigen sandwich principle. The antigens within the reagent capture predominantly anti‑SARS‑CoV‑2 IgG, but also anti‑SARS‑CoV‑2 IgA and IgM. Total duration of assay: 18 minutes.

2nd incubation: After addition of streptavidin-coated microparticles, the complex becomes bound to the solid phase via interaction of biotin and streptavidin.

Results are determined via a calibration curve which is instrument-specifically generated by 2‑point calibration and a master curve provided via the reagent barcode or e‑barcode.

Analytical measuring interval

The analytical measuring interval is 0.40‑250 U/mL. Numeric values are interpreted as \"negative\" (< 0.8 U/mL) and as \"positive\" (≥ 0.80 U/mL). Please see Interpretation of the results section. When sample results exceed the upper limit of the analytical measuring interval, refer to the Dilution section below. Values above the measuring range are reported as > 250 U/mL (or up to 2500 U/mL for 10‑fold diluted samples).

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank = 0.30 U/mL

Limit of Detection = 0.35 U/mL

Limit of Quantitation = 0.40 U/mL

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank corresponds to the highest measurement result that is likely to be observed for analyte-free samples with a probability of 95 %. The Limit of Blank was estimated as the 95th percentile value from n ≥ 60 measurements of analyte-free samples over several independent series. The Limit of Blank is 0.30 U/mL.

The Limit of Detection is the lowest concentration of antibodies to SARS‑CoV‑2 in a sample that can be detected with a probability of 95 %. The Limit of Detection was calculated based on the Limit of Blank and the standard deviation of low concentration samples. The Limit of Detection is 0.35 U/mL.

The Limit of Quantitation is defined as the lowest amount of analyte in a sample that can be accurately quantified with a CV ≤ 20 %. It has been determined using low concentration of anti‑SARS‑CoV‑2‑S samples. The Limit of Quantitation is 0.40 U/mL.

For cobas e 411 analyzer: test number 2550
For cobas e 601 and cobas e 602 analyzers: Application Code Number 71
For cobas e 801 analyzer: Application Code Number 10230

The reagents in the kit have been assembled into a ready‑for‑use unit that cannot be separated.

cobas e 411, cobas e 601, and cobas e 602 analyzers:

All information required for correct operation is read in from the respective reagent barcodes.

cobas e 801 analyzer:

All information required for correct operation is available via the cobas link.

Store at 2‑8 °C.

Do not freeze.

Store the Elecsys reagent kit / cobas e pack upright in order to ensure complete availability of the microparticles during automatic mixing prior to use.

Traceability: This method has been standardized against the internal Roche standard for anti‑SARS‑CoV‑2‑S. This standard consists of an equimolar mixture of 2 monoclonal antibodies that bind Spike‑1 RBD at 2 different epitopes. 1 nM of these antibodies correspond to 20 U/mL of the Elecsys Anti‑SARS‑CoV‑2 S assay. No international standard is currently available for anti‑SARS‑CoV‑2‑S.

Note: The defined unit is specific for the Elecsys Anti‑SARS‑CoV‑2 S assay and must not be used interchangeably with units of other assays.

Every Elecsys reagent set has a barcoded label containing specific information for calibration of the particular reagent lot. The predefined master curve is adapted to the analyzer using the relevant CalSet.

Calibration frequency: Calibration must be performed once per reagent lot using fresh reagent (i.e. not more than 24 hours since the same reagent kit was registered on the analyzer).

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Renewed calibration is recommended as follows:

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

Precision was determined using Elecsys reagents, samples and controls in a protocol (EP05‑A3) of the CLSI: 1 run per day with 5 replicates of each sample for 5 days. The following results were obtained:

Repeatability and Intermediate precision

Precision study for evaluation of Lot-to-lot and Between-platform variability

An additional precision study for the estimation of lot-to-lot precision component was conducted with the design similar to the single-site precision study and with 2 additional lots.

Lot-to-lot precision

Lot-to-lot variability was evaluated for the cobas e 801 analyzer with 3 lots.

Between‑platform precision

Between-platform precision was evaluated as between different platform variability (1 cobas e 411, 1 cobas e 601, and 1 cobas e 801 analyzer).

Reproducibility including Lot-to-lot and Between-platform variability

SARS‑CoV‑2, the causative agent of Coronavirus Disease 2019 (COVID‑19), is an enveloped, single-stranded RNA Betacoronavirus. 7 coronaviruses have been identified as agents of human infection, causing disease ranging from mild common cold to severe respiratory failure.

SARS‑CoV‑2 is transmitted primarily from person-to-person through respiratory droplets and aerosols.

Coronavirus genomes encode 4 main structural proteins: spike (S), envelope (E), membrane (M), and nucleocapsid (N). The S protein is a very large transmembrane protein that assembles into trimers to form the distinctive surface spikes of coronaviruses. Each S monomer consists of an N‑terminal S1 domain and a membrane-proximal S2 domain. The virus gains entry to the host cell through binding of the S protein to the angiotensin-converting enzyme 2 (ACE2), which is enzymatically active on the surface of numerous cell types including the alveolar type II cells of the lung and epithelial cells of the oral mucosa.

Upon infection with SARS‑CoV‑2, the host mounts an immune response against the virus, typically including production of specific antibodies against viral antigens. IgM and IgG antibodies to SARS‑CoV‑2 appear to arise nearly simultaneously in blood.

Serologic assays can play an important role in understanding viral epidemiology in the general population. The Elecsys Anti‑SARS‑CoV‑2 S assay uses a recombinant protein representing the RBD of the spike antigen in a double‑antigen sandwich assay format. The Elecsys Anti‑SARS‑CoV‑2 S assay detects antibodies to SARS‑CoV‑2 spike protein RBD.

cobas e 411, cobas e 601, and cobas e 602 analyzers:

The reagent rackpack is labeled as ACOV2S.

cobas e 801 analyzer:

The cobas e pack is labeled as ACOV2S.

Calibrators are available separately. See Materials required (but not provided) section of this Method Sheet.

For use under Emergency Use Authorization only.
This test has not been FDA-cleared or ‑approved; this test has been authorized by FDA under an Emergency Use Authorization (EUA) for use by authorized laboratories; by laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. 263a, that meet requirements to perform high complexity tests.
This test has been authorized only for detecting antibodies against SARS‑CoV‑2, not for any other viruses or pathogens.
This test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostic tests for detection and/or diagnosis of COVID‑19 under Section 564(b)(1) of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C § 360bbb‑3(b)(1), unless the authorization is terminated or revoked sooner.

For in vitro diagnostic use.
Do not use reagents beyond the labeled expiration date.
Exercise the normal precautions required for handling all laboratory reagents.
Disposal of all waste material should be in accordance with local guidelines.
Safety data sheet available for professional user on request.

For USA: Caution: Federal law restricts this device to sale by or on the order of a physician.

This kit contains components classified as follows in accordance with the Regulation (EC) No. 1272/2008:

Warning

Prevention:

Response:

Disposal:

Product safety labeling follows EU GHS guidance.

Contact phone: 1-800-428-2336

Avoid foam formation in all reagents and sample types (specimens, calibrators and controls).

For quality control, use PreciControl Anti‑SARS‑CoV‑2 S. Please refer to the PreciControl Method Sheet for instructions for use, including description of the controls and the expected results.

In addition, other commercially available quality control material can be used that covers at least two levels of analyte.

Controls for the various concentration ranges should be run individually at least once every 24 hours when the test is in use, once per reagent kit / cobas e pack, and following each calibration.

The control intervals and limits should be adapted to each laboratory’s individual requirements. Values obtained should fall within the defined limits. Follow your laboratory’s quality control procedures if the results obtained do not fall within the acceptable limits. Please refer to PreciControl instructions for use. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

If necessary, repeat the measurement of the samples concerned.

Follow the applicable government regulations and local and accrediting group guidelines for quality control.

Only the specimens listed below were tested and found acceptable.

Serum collected using standard sampling tubes or tubes containing separating gel.

Li‑heparin, dipotassium EDTA (K₂‑EDTA), tripotassium EDTA (K₃‑EDTA), and sodium citrate plasma.

Plasma tubes containing separating gel can be used.

Criterion: Slope 1.00 ± 0.10 + bias at 0.8 U/mL ± 20 %.

For native samples collected in sodium citrated plasma: Slope 0.84 ± 0.10.

Results with sample materials other than serum were compared to serum results. Linear regression was performed for results obtained with the different sample materials, comparison of slope and bias verified comparability to serum results.

Sampling devices containing liquid anticoagulants have a dilution effect resulting in lower values (U/mL) for individual patient specimens. In order to minimize dilution effects it is essential that respective sampling devices are filled completely according to manufacturer’s instructions. For citrated plasma (1 part citrate solution + 9 parts blood), the dilution effect must be taken into account.

Stable for 14 days at 15‑25 °C, 14 days at 2‑8 °C, 3 months at ‑20 °C (± 5 °C). The samples may be frozen 3 times.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

Specimens should not be subsequently altered with additives (e.g. biocides, anti-oxidants or substances that could possibly change the pH or ionic strength of the sample) in order to avoid erroneous findings.

Centrifuge samples containing precipitates and thawed samples before performing the assay.

Do not use heat‑inactivated samples.

Ensure the samples and calibrators are at 20‑25 °C prior to measurement.

Due to possible evaporation effects, samples and calibrators on the analyzers should be analyzed/measured within 2 hours.

Sample stability claims were established by experimental data by the manufacturer or based on reference literature and only for the temperatures/time frames as stated in the method sheet. It is the responsibility of the individual laboratory to use all available references and/or its own studies to determine specific stability criteria for its laboratory.

Elecsys Anti‑SARS‑CoV‑2 S for use on the cobas e analyzers is an electrochemiluminescence immunoassay intended for qualitative and semi-quantitative detection of antibodies to SARS‑CoV‑2 spike (S) protein receptor binding domain (RBD) in human serum and plasma (lithium heparin, dipotassium-EDTA, tripotassium-EDTA, and sodium citrate). The Elecsys Anti‑SARS‑CoV‑2 S assay is intended as an aid in identifying individuals with an adaptive immune response to SARS‑CoV‑2, indicating recent or prior infection. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity. The Elecsys Anti‑SARS‑CoV‑2 S assay should not be used to diagnose acute SARS‑CoV‑2 infection.
Testing is limited to laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. 263a, that meet requirements to perform moderate or high complexity tests.

Results are for the detection of SARS‑CoV‑2 antibodies. Antibodies to SARS‑CoV‑2 are generally detectable in blood several days after initial infection, although the duration of time antibodies are present post-infection is not well characterized. Individuals may have detectable virus present for several weeks following seroconversion.

Laboratories within the United States and its territories are required to report all results to the appropriate public health authorities. The sensitivity of the Elecsys Anti‑SARS‑CoV‑2 S assay early after infection is unknown. Negative results do not preclude acute SARS‑CoV‑2 infection. If acute infection is suspected, direct testing for SARS‑CoV‑2 is necessary.

False positive results for Elecsys Anti‑SARS‑CoV‑2 S assay may occur due to cross-reactivity from pre‑existing antibodies or other possible causes.

The Elecsys Anti‑SARS‑CoV‑2 S assay is only for use under the Food and Drug Administration’s Emergency Use Authorization.

The electrochemiluminescence immunoassay “ECLIA” is intended for use on cobas e immunoassay analyzers.

Double-antigen sandwich principle. The antigens within the reagent captures predominantly anti‑SARS‑CoV‑2 IgG, but also anti‑SARS‑CoV‑2 IgA and IgM. Total duration of assay: 18 minutes.

2nd incubation: After addition of streptavidin-coated microparticles, the complex becomes bound to the solid phase via interaction of biotin and streptavidin.

Results are determined via a calibration curve which is instrument-specifically generated by 2‑point calibration and a master curve provided via the reagent barcode or e‑barcode.

Analytical measuring interval

The analytical measuring interval is 0.40‑250 U/mL. Numeric values are interpreted as \"negative\" (< 0.8 U/mL) and as \"positive\" (≥ 0.80 U/mL). Please see Interpretation of the results section. When sample results exceed the upper limit of the analytical measuring interval, refer to the Dilution section below. Values above the measuring range are reported as > 250 U/mL (or up to 2500 U/mL for 10‑fold diluted samples).

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank = 0.30 U/mL

Limit of Detection = 0.35 U/mL

Limit of Quantitation = 0.40 U/mL

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank corresponds to the highest measurement result that is likely to be observed for analyte-free samples with a probability of 95 %. The Limit of Blank was estimated as the 95th percentile value from n ≥ 60 measurements of analyte-free samples over several independent series. The Limit of Blank is 0.30 U/mL.

The Limit of Detection is the lowest concentration of antibodies to SARS‑CoV‑2 in a sample that can be detected with a probability of 95 %. The Limit of Detection was calculated based on the Limit of Blank and the standard deviation of low concentration samples. The Limit of Detection is 0.35 U/mL.

The Limit of Quantitation is defined as the lowest amount of analyte in a sample that can be accurately quantified with a CV ≤ 20 %. It has been determined using low concentration of anti‑SARS‑CoV‑2‑S samples. The Limit of Quantitation is 0.40 U/mL.

For cobas e 411 analyzer: test number 2550
For cobas e 601 and cobas e 602 analyzers: Application Code Number 71
For cobas e 801 analyzer: Application Code Number 10230

The reagents in the kit have been assembled into a ready‑for‑use unit that cannot be separated.

cobas e 411, cobas e 601, and cobas e 602 analyzers:

All information required for correct operation is read in from the respective reagent barcodes.

cobas e 801 analyzer:

All information required for correct operation is available via the cobas link.

Store at 2‑8 °C.

Do not freeze.

Store the Elecsys reagent kit / cobas e pack upright in order to ensure complete availability of the microparticles during automatic mixing prior to use.

Traceability: This method has been standardized against the internal Roche standard for anti‑SARS‑CoV‑2‑S. This standard consists of an equimolar mixture of 2 monoclonal antibodies that bind Spike‑1 RBD at 2 different epitopes. 1 nM of these antibodies correspond to 20 U/mL of the Elecsys Anti‑SARS‑CoV‑2 S assay. No international standard is currently available for anti‑SARS‑CoV‑2‑S.

Note: The defined unit is specific for the Elecsys Anti‑SARS‑CoV‑2 S assay and must not be used interchangeably with units of other assays.

Every Elecsys reagent set has a barcoded label containing specific information for calibration of the particular reagent lot. The predefined master curve is adapted to the analyzer using the relevant CalSet.

Calibration frequency: Calibration must be performed once per reagent lot using fresh reagent (i.e. not more than 24 hours since the same reagent kit was registered on the analyzer).

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Renewed calibration is recommended as follows:

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

Precision was determined using Elecsys reagents, samples and controls in a protocol (EP05‑A3) of the CLSI: 1 run per day with 5 replicates of each sample for 5 days. The following results were obtained:

Repeatability and Intermediate precision

Precision study for evaluation of Lot-to-lot and Between-platform variability

An additional precision study for the estimation of lot-to-lot precision component was conducted with the design similar to the single-site precision study and with 2 additional lots.

Lot-to-lot precision

Lot-to-lot variability was evaluated for the cobas e 801 analyzer with 3 lots.

Between‑platform precision

Between-platform precision was evaluated as between different platform variability (1 cobas e 411, 1 cobas e 601, and 1 cobas e 801 analyzer).

Reproducibility including Lot-to-lot and Between-platform variability

SARS‑CoV‑2, the causative agent of Coronavirus Disease 2019 (COVID‑19), is an enveloped, single-stranded RNA Betacoronavirus. 7 coronaviruses have been identified as agents of human infection, causing disease ranging from mild common cold to severe respiratory failure.

SARS‑CoV‑2 is transmitted primarily from person-to-person through respiratory droplets and aerosols.

Coronavirus genomes encode 4 main structural proteins: spike (S), envelope (E), membrane (M), and nucleocapsid (N). The S protein is a very large transmembrane protein that assembles into trimers to form the distinctive surface spikes of coronaviruses. Each S monomer consists of an N‑terminal S1 domain and a membrane-proximal S2 domain. The virus gains entry to the host cell through binding of the S protein to the angiotensin-converting enzyme 2 (ACE2), which is enzymatically active on the surface of numerous cell types including the alveolar type II cells of the lung and epithelial cells of the oral mucosa.

Upon infection with SARS‑CoV‑2, the host mounts an immune response against the virus, typically including production of specific antibodies against viral antigens. IgM and IgG antibodies to SARS‑CoV‑2 appear to arise nearly simultaneously in blood.

Serologic assays can play an important role in understanding viral epidemiology in the general population. The Elecsys Anti‑SARS‑CoV‑2 S assay uses a recombinant protein representing the RBD of the S antigen in a double‑antigen sandwich assay format.

cobas e 411, cobas e 601, and cobas e 602 analyzers:

The reagent rackpack is labeled as ACOV2S.

cobas e 801 analyzer:

The cobas e pack is labeled as ACOV2S.

Calibrators are available separately. See Materials required (but not provided) section of this Method Sheet.

For use under Emergency Use Authorization only.
This test has not been FDA-cleared or ‑approved; this test has been authorized by FDA under an Emergency Use Authorization (EUA) for use by laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. 263a, that meet requirements to perform high complexity tests.
This test has been authorized only for detecting antibodies against SARS‑CoV‑2, not for any other viruses or pathogens.
This test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostic tests for detection and/or diagnosis of COVID‑19 under Section 564(b)(1) of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C § 360bbb‑3(b)(1), unless the authorization is terminated or revoked sooner.

For in vitro diagnostic use.
Do not use reagents beyond the labeled expiration date.
Exercise the normal precautions required for handling all laboratory reagents.
Disposal of all waste material should be in accordance with local guidelines.
Safety data sheet available for professional user on request.

For USA: Caution: Federal law restricts this device to sale by or on the order of a physician.

This kit contains components classified as follows in accordance with the Regulation (EC) No. 1272/2008:

Warning

Prevention:

Response:

Disposal:

Product safety labeling follows EU GHS guidance.

Contact phone: 1-800-428-2336

Avoid foam formation in all reagents and sample types (specimens, calibrators and controls).

For quality control, use PreciControl Anti‑SARS‑CoV‑2 S. Please refer to the PreciControl Method Sheet for instructions for use, including description of the controls and the expected results.

In addition, other commercially available quality control material can be used that covers at least two levels of analyte.

Controls for the various concentration ranges should be run individually at least once every 24 hours when the test is in use, once per reagent kit / cobas e pack, and following each calibration.

The control intervals and limits should be adapted to each laboratory’s individual requirements. Values obtained should fall within the defined limits. Follow your laboratory’s quality control procedures if the results obtained do not fall within the acceptable limits. Please refer to PreciControl instructions for use. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

If necessary, repeat the measurement of the samples concerned.

Follow the applicable government regulations and local and accrediting group guidelines for quality control.

Only the specimens listed below were tested and found acceptable.

Serum collected using standard sampling tubes or tubes containing separating gel.

Li‑heparin, dipotassium EDTA (K₂‑EDTA), tripotassium EDTA (K₃‑EDTA), and sodium citrate plasma.

Plasma tubes containing separating gel can be used.

Criterion: Slope 1.00 ± 0.10 + bias at 0.8 U/mL ± 20 %.

For native samples collected in sodium citrated plasma: Slope 0.84 ± 0.10.

Results with sample materials other than serum were compared to serum results. Linear regression was performed for results obtained with the different sample materials, comparison of slope and bias verified comparability to serum results.

Sampling devices containing liquid anticoagulants have a dilution effect resulting in lower values (U/mL) for individual patient specimens. In order to minimize dilution effects it is essential that respective sampling devices are filled completely according to manufacturer’s instructions. For citrated plasma (1 part citrate solution + 9 parts blood), the dilution effect must be taken into account.

Stable for 3 days at 15‑25 °C, 7 days at 2‑8 °C, 28 days at ‑20 °C (± 5 °C). The samples may be frozen once.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

Specimens should not be subsequently altered with additives (e.g. biocides, anti-oxidants or substances that could possibly change the pH or ionic strength of the sample) in order to avoid erroneous findings.

Centrifuge samples containing precipitates and thawed samples before performing the assay.

Do not use heat‑inactivated samples.

Ensure the samples and calibrators are at 20‑25 °C prior to measurement.

Due to possible evaporation effects, samples and calibrators on the analyzers should be analyzed/measured within 2 hours.

Sample stability claims were established by experimental data by the manufacturer or based on reference literature and only for the temperatures/time frames as stated in the method sheet. It is the responsibility of the individual laboratory to use all available references and/or its own studies to determine specific stability criteria for its laboratory.

Elecsys Anti‑SARS‑CoV‑2 S for use on the cobas e analyzers is an electrochemiluminescence immunoassay intended for qualitative and semi-quantitative detection of antibodies to SARS‑CoV‑2 in human serum and plasma (lithium heparin, dipotassium-EDTA, tripotassium-EDTA, and sodium citrate). The Elecsys Anti‑SARS‑CoV‑2 S assay is intended for use as an aid in identifying individuals with an adaptive immune response to SARS‑CoV‑2, indicating recent or prior infection. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity. The Elecsys Anti‑SARS‑CoV‑2 S assay should not be used to diagnose or exclude acute SARS‑CoV‑2 infection.
Testing is limited to laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. 263a, that meet requirements to perform moderate or high complexity tests.

Results are for the detection of SARS‑CoV‑2 antibodies. Antibodies to SARS‑CoV‑2 are generally detectable in blood several days after initial infection, although the duration of time antibodies are present post-infection is not well characterized. Individuals may have detectable virus present for several weeks following seroconversion.

Laboratories within the United States and its territories are required to report all results to the appropriate public health authorities. The sensitivity of the Elecsys Anti‑SARS‑CoV‑2 S assay early after infection is unknown. Negative results do not preclude acute SARS‑CoV‑2 infection. If acute infection is suspected, direct testing for SARS‑CoV‑2 is necessary.

False positive results for Elecsys Anti‑SARS‑CoV‑2 S assay may occur due to cross-reactivity from pre‑existing antibodies or other possible causes.

The Elecsys Anti‑SARS‑CoV‑2 S assay is only for use under the Food and Drug Administration’s Emergency Use Authorization.

The electrochemiluminescence immunoassay “ECLIA” is intended for use on cobas e immunoassay analyzers.

Double-antigen sandwich principle. The antigens within the reagent capture predominantly anti‑SARS‑CoV‑2 IgG, but also anti‑SARS‑CoV‑2 IgA and IgM. Total duration of assay: 18 minutes.

2nd incubation: After addition of streptavidin-coated microparticles, the complex becomes bound to the solid phase via interaction of biotin and streptavidin.

Results are determined via a calibration curve which is instrument-specifically generated by 2‑point calibration and a master curve provided via the reagent barcode or e‑barcode.

Analytical measuring interval

The analytical measuring interval is 0.40‑250 U/mL. Numeric values are interpreted as \"negative\" (< 0.8 U/mL) and as \"positive\" (≥ 0.80 U/mL). Please see Interpretation of the results section. When sample results exceed the upper limit of the analytical measuring interval, refer to the Dilution section below. Values above the measuring range are reported as > 250 U/mL (or up to 2500 U/mL for 10‑fold diluted samples).

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank = 0.30 U/mL

Limit of Detection = 0.35 U/mL

Limit of Quantitation = 0.40 U/mL

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank corresponds to the highest measurement result that is likely to be observed for analyte-free samples with a probability of 95 %. The Limit of Blank was estimated as the 95th percentile value from n ≥ 60 measurements of analyte-free samples over several independent series. The Limit of Blank is 0.30 U/mL.

The Limit of Detection is the lowest concentration of antibodies to SARS‑CoV‑2 in a sample that can be detected with a probability of 95 %. The Limit of Detection was calculated based on the Limit of Blank and the standard deviation of low concentration samples. The Limit of Detection is 0.35 U/mL.

The Limit of Quantitation is defined as the lowest amount of analyte in a sample that can be accurately quantified with a CV ≤ 20 %. It has been determined using low concentration of anti‑SARS‑CoV‑2‑S samples. The Limit of Quantitation is 0.40 U/mL.

For cobas e 411 analyzer: test number 2550
For cobas e 601 and cobas e 602 analyzers: Application Code Number 71
For cobas e 801 analyzer: Application Code Number 10230

The reagents in the kit have been assembled into a ready‑for‑use unit that cannot be separated.

cobas e 411, cobas e 601, and cobas e 602 analyzers:

All information required for correct operation is read in from the respective reagent barcodes.

cobas e 801 analyzer:

All information required for correct operation is available via the cobas link.

Store at 2‑8 °C.

Do not freeze.

Store the Elecsys reagent kit / cobas e pack upright in order to ensure complete availability of the microparticles during automatic mixing prior to use.

Traceability: This method has been standardized against the internal Roche standard for anti‑SARS‑CoV‑2‑S. This standard consists of an equimolar mixture of 2 monoclonal antibodies that bind Spike‑1 RBD at 2 different epitopes. 1 nM of these antibodies correspond to 20 U/mL of the Elecsys Anti‑SARS‑CoV‑2 S assay. No international standard is currently available for anti‑SARS‑CoV‑2‑S.

Note: The defined unit is specific for the Elecsys Anti‑SARS‑CoV‑2 S assay and must not be used interchangeably with units of other assays.

Every Elecsys reagent set has a barcoded label containing specific information for calibration of the particular reagent lot. The predefined master curve is adapted to the analyzer using the relevant CalSet.

Calibration frequency: Calibration must be performed once per reagent lot using fresh reagent (i.e. not more than 24 hours since the same reagent kit was registered on the analyzer).

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Renewed calibration is recommended as follows:

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

Precision was determined using Elecsys reagents, samples and controls in a protocol (EP05‑A3) of the CLSI: 1 run per day with 5 replicates of each sample for 5 days. The following results were obtained:

Repeatability and Intermediate precision

Precision study for evaluation of Lot-to-lot and Between-platform variability

An additional precision study for the estimation of lot-to-lot precision component was conducted with the design similar to the single-site precision study and with 2 additional lots.

Lot-to-lot precision

Lot-to-lot variability was evaluated for the cobas e 801 analyzer with 3 lots.

Between‑platform precision

Between-platform precision was evaluated as between different platform variability (1 cobas e 411, 1 cobas e 601, and 1 cobas e 801 analyzer).

Reproducibility including Lot-to-lot and Between-platform variability

SARS‑CoV‑2, the causative agent of Coronavirus Disease 2019 (COVID‑19), is an enveloped, single-stranded RNA Betacoronavirus. 7 coronaviruses have been identified as agents of human infection, causing disease ranging from mild common cold to severe respiratory failure.

SARS‑CoV‑2 is transmitted primarily from person-to-person through respiratory droplets and aerosols.

Coronavirus genomes encode 4 main structural proteins: spike (S), envelope (E), membrane (M), and nucleocapsid (N). The S protein is a very large transmembrane protein that assembles into trimers to form the distinctive surface spikes of coronaviruses. Each S monomer consists of an N‑terminal S1 domain and a membrane-proximal S2 domain. The virus gains entry to the host cell through binding of the S protein to the angiotensin-converting enzyme 2 (ACE2), which is enzymatically active on the surface of numerous cell types including the alveolar type II cells of the lung and epithelial cells of the oral mucosa.

Upon infection with SARS‑CoV‑2, the host mounts an immune response against the virus, typically including production of specific antibodies against viral antigens. IgM and IgG antibodies to SARS‑CoV‑2 appear to arise nearly simultaneously in blood.

Serologic assays can play an important role in understanding viral epidemiology in the general population. The Elecsys Anti‑SARS‑CoV‑2 S assay uses a recombinant protein representing the RBD of the spike antigen in a double‑antigen sandwich assay format. The Elecsys Anti‑SARS‑CoV‑2 S assay detects antibodies to SARS‑CoV‑2 spike protein RBD.

cobas e 411, cobas e 601, and cobas e 602 analyzers:

The reagent rackpack is labeled as ACOV2S.

cobas e 801 analyzer:

The cobas e pack is labeled as ACOV2S.

Calibrators are available separately. See Materials required (but not provided) section of this Method Sheet.

For use under Emergency Use Authorization only.
This test has not been FDA-cleared or ‑approved; this test has been authorized by FDA under an Emergency Use Authorization (EUA) for use by authorized laboratories; by laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. 263a, that meet requirements to perform high complexity tests.
This test has been authorized only for detecting antibodies against SARS‑CoV‑2, not for any other viruses or pathogens.
This test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostic tests for detection and/or diagnosis of COVID‑19 under Section 564(b)(1) of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C § 360bbb‑3(b)(1), unless the authorization is terminated or revoked sooner.

For in vitro diagnostic use.
Do not use reagents beyond the labeled expiration date.
Exercise the normal precautions required for handling all laboratory reagents.
Disposal of all waste material should be in accordance with local guidelines.
Safety data sheet available for professional user on request.

For USA: Caution: Federal law restricts this device to sale by or on the order of a physician.

This kit contains components classified as follows in accordance with the Regulation (EC) No. 1272/2008:

Warning

Prevention:

Response:

Disposal:

Product safety labeling follows EU GHS guidance.

Contact phone: 1-800-428-2336

Avoid foam formation in all reagents and sample types (specimens, calibrators and controls).

For quality control, use PreciControl Anti‑SARS‑CoV‑2 S. Please refer to the PreciControl Method Sheet for instructions for use, including description of the controls and the expected results.

In addition, other commercially available quality control material can be used that covers at least two levels of analyte.

Controls for the various concentration ranges should be run individually at least once every 24 hours when the test is in use, once per reagent kit / cobas e pack, and following each calibration.

The control intervals and limits should be adapted to each laboratory’s individual requirements. Values obtained should fall within the defined limits. Follow your laboratory’s quality control procedures if the results obtained do not fall within the acceptable limits. Please refer to PreciControl instructions for use. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

If necessary, repeat the measurement of the samples concerned.

Follow the applicable government regulations and local and accrediting group guidelines for quality control.

Only the specimens listed below were tested and found acceptable.

Serum collected using standard sampling tubes or tubes containing separating gel.

Li‑heparin, dipotassium EDTA (K₂‑EDTA), tripotassium EDTA (K₃‑EDTA), and sodium citrate plasma.

Plasma tubes containing separating gel can be used.

Criterion: Slope 1.00 ± 0.10 + bias at 0.8 U/mL ± 20 %.

For native samples collected in sodium citrated plasma: Slope 0.84 ± 0.10.

Results with sample materials other than serum were compared to serum results. Linear regression was performed for results obtained with the different sample materials, comparison of slope and bias verified comparability to serum results.

Sampling devices containing liquid anticoagulants have a dilution effect resulting in lower values (U/mL) for individual patient specimens. In order to minimize dilution effects it is essential that respective sampling devices are filled completely according to manufacturer’s instructions. For citrated plasma (1 part citrate solution + 9 parts blood), the dilution effect must be taken into account.

Stable for 14 days at 15‑25 °C, 14 days at 2‑8 °C, 3 months at ‑20 °C (± 5 °C). The samples may be frozen 3 times.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

Specimens should not be subsequently altered with additives (e.g. biocides, anti-oxidants or substances that could possibly change the pH or ionic strength of the sample) in order to avoid erroneous findings.

Centrifuge samples containing precipitates and thawed samples before performing the assay.

Do not use heat‑inactivated samples.

Ensure the samples and calibrators are at 20‑25 °C prior to measurement.

Due to possible evaporation effects, samples and calibrators on the analyzers should be analyzed/measured within 2 hours.

Sample stability claims were established by experimental data by the manufacturer or based on reference literature and only for the temperatures/time frames as stated in the method sheet. It is the responsibility of the individual laboratory to use all available references and/or its own studies to determine specific stability criteria for its laboratory.