QUANTA FLASH ACL LGA, QUANTA FLASH B2GP1 IGA
Device Facts
| Record ID | K120817 |
|---|---|
| Device Name | QUANTA FLASH ACL LGA, QUANTA FLASH B2GP1 IGA |
| Applicant | Inova Diagnostics, Inc. |
| Product Code | MID · Immunology |
| Decision Date | Feb 26, 2013 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 866.5660 |
| Device Class | Class 2 |
Indications for Use
QUANTA Flash β2GP1 IgA: Fully automated chemiluminescent immunoassay for the semi-quantitative measurement of anti-β2 glycoprotein-1 (β2GP1) IgA antibodies in human citrated plasma and serum on the BIO-FLASH® instrument, as an aid in the diagnosis of thrombotic disorders related to primary and secondary antiphospholipid syndrome, when used in conjunction with other laboratory and clinical findings. QUANTA Flash β2GP1 IgA Controls: The QUANTA Flash β2GP1 IgA Controls are intended for the quality control purposes of the QUANTA Flash β2GP1 IgA assay performed on the BIO-FLASH® instrument. QUANTA Flash aCL IgA: Fully automated chemiluminescent immunoassay for the semi-quantitative measurement of anti-cardiolipin (aCL) IgA antibodies in human citrated plasma and serum on the BIO-FLASH® instrument, as an aid in the diagnosis of thrombotic disorders related to primary and secondary antiphospholipid syndrome (APS), when used in conjunction with other laboratory and clinical findings. QUANTA Flash aCL IgA Controls: The QUANTA Flash aCL IgA Controls are intended for quality control purposes of the QUANTA Flash aCL IgA assay performed on the BIO-FLASH® instrument.
Device Story
Device is a fully automated chemiluminescent immunoassay (CIA) for semi-quantitative measurement of IgA antibodies to β2-glycoprotein-1 or cardiolipin in human serum/citrated plasma. Operates on BIO-FLASH instrument; uses magnetic particles coated with purified human β2GP1 or bovine cardiolipin/human β2GP1. Patient sample mixed with beads and assay buffer; incubated; washed; isoluminol-conjugated anti-human IgA tracer added. After further incubation and washing, triggers (catalyst/oxidant) added to induce chemiluminescence. Light output (RLU) measured by optical system; proportional to antibody concentration. Results calculated via 4-parameter logistic curve (4PLC) against lot-specific master curve. Used in clinical laboratories to aid diagnosis of thrombotic disorders associated with APS. Output provides semi-quantitative values (CU) to assist clinicians in diagnostic decision-making.
Clinical Evidence
Clinical validation performed on 632 patient samples (APS and non-APS controls). Sensitivity for total APS: 33.6% (β2GP1 IgA) and 31.5% (aCL IgA). Specificity (excluding SLE): 99.1% for both assays. Method comparison against predicate ELISAs showed overall percent agreement of 87.8% (β2GP1 IgA) and 89% (aCL IgA) in clinical validation sets. Analytical performance included precision (total CVs generally <15%), linearity, and interference testing.
Technological Characteristics
Solid phase: paramagnetic beads coated with β2GP1 or cardiolipin. Detection: isoluminol-conjugated monoclonal anti-human IgA. Energy source: BIO-FLASH instrument (chemiluminescence). Dimensions/form factor: reagent cartridge system. Connectivity: BIO-FLASH instrument system. Sterilization: N/A (reagents). Software: BIO-FLASH system software. Algorithm: 4-parameter logistic curve (4PLC) data reduction.
Indications for Use
Indicated for use as an aid in the diagnosis of thrombotic disorders related to primary and secondary antiphospholipid syndrome (APS) in patients, when used in conjunction with other laboratory and clinical findings. For prescription use only.
Regulatory Classification
Identification
A multiple autoantibodies immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoantibodies (antibodies produced against the body's own tissues) in serum and other body fluids. Measurement of multiple autoantibodies aids in the diagnosis of autoimmune disorders (disease produced when the body's own tissues are injured by autoantibodies).
Predicate Devices
- QUANTA Lite β2GP1 IgA ELISA (k973006)
- QUANTA Lite ACA III IgA ELISA (k953366)
Submission Summary (Full Text)
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# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY
A. 510(k) Number:
k120817
B. Purpose for Submission:
New Device
C. Measurand:
IgA antibody to Cardiolipin (CL)
IgA antibody to Beta-2-Glycopropein I (β2GPI)
D. Type of Test:
Semi-quantitative chemiluminescent immunoassay (CIA)
E. Applicant:
INOVA Diagnostics, Inc.
F. Proprietary and Established Names:
QUANTA Flash β2GP1 IgA
QUANTA Flash aCL IgA
QUANTA Flash β2GP1 IgA Controls
QUANTA Flash aCL IgA Controls
G. Regulatory Information:
1. Regulation section:
21 CFR §866.5660 – Multiple autoantibodies immunological test system
21 CFR §862.1150 – Calibrator
21 CFR § 862.1660 – Quality Control Material (assayed and unassayed)
2. Classification:
Class II (Assays, Calibrator)
Class I (Controls)
3. Product code:
MID, System Test, Anti-Cardiolipin Immunological
MSV, Antibodies, β2-Glycoprotein I (β2-GPI)
JJX, Single (specified) Analyte Controls (Assayed and Unassayed)
4. Panel:
Immunology (82) (Assays)
Chemistry (75) (Controls and Calibrators)
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H. Intended Use:
1. Intended use(s):
QUANTA Flash β2GP1 IgA: Fully automated chemiluminescent immunoassay for the semi-quantitative measurement of anti-β2 glycoprotein-1 (β2GP1) IgA antibodies in human citrated plasma and serum on the BIO-FLASH® instrument, as an aid in the diagnosis of thrombotic disorders related to primary and secondary antiphospholipid syndrome, when used in conjunction with other laboratory and clinical findings.
QUANTA Flash β2GP1 IgA Controls: The QUANTA Flash β2GP1 IgA Controls are intended for the quality control purposes of the QUANTA Flash β2GP1 IgA assay performed on the BIO-FLASH® instrument.
QUANTA Flash aCL IgA: Fully automated chemiluminescent immunoassay for the semi-quantitative measurement of anti-cardiolipin (aCL) IgA antibodies in human citrated plasma and serum on the BIO-FLASH® instrument, as an aid in the diagnosis of thrombotic disorders related to primary and secondary antiphospholipid syndrome (APS), when used in conjunction with other laboratory and clinical findings.
QUANTA Flash aCL IgA Controls: The QUANTA Flash aCL IgA Controls are intended for quality control purposes of the QUANTA Flash aCL IgA assay performed on the BIO-FLASH® instrument.
2. Indication(s) for use:
Same as Intended Use
3. Special conditions for use statement(s):
For Prescription Use only
4. Special instrument requirements:
BIO-FLASH® Instrument System (k083518)
I. Device Description:
QUANTA Flash β2GP1 IgA Kit:
1. QUANTA Flash β2GP1 IgA Kit Reagent Pack (cartridge): One cartridge contains sufficient material for 50 tests. Each reagent pack contains the following sealed reagent tubes:
a. Microparticle Reagent: 1 vial of β2GP1 (purified human) coated magnetic particles preserved in buffer solution.
b. Assay Buffer: 1 vial of Tris-buffered saline with protein stabilizers and surfactant. Preservatives: sodium azide and chloramphenicol.
c. Tracer IgA: 1 vial of isoluminol conjugated monoclonal anti-human IgA antibodies in phosphate buffered saline with protein (bovine) stabilizer. Preservative: sodium azide.
d. 1 vial of sample diluent used for the regular predilution of the sample and automatic dilution in the rerun.
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2. β2GP1 IgA Calibrator 1: 1 x 1 mL barcoded tube of a solution with human anti-β2GP1 IgA in a phosphate buffer, containing bovine serum albumin, stabilizers and preservative. Each vial contains sufficient material for 10 uses.
3. β2GP1 IgA Calibrator 2: 1 x 1 mL barcoded tube of a solution with human anti-β2GP1 IgA in a phosphate buffer, containing bovine serum albumin, stabilizers and preservative. Each vial contains sufficient material for 10 uses.
**QUANTA Flash β2GP1 IgA Control Kit:** Each control kit contains three vials each of Low Control and High Control. Control material contains human antibodies to β2GP1 in a Tris-buffered saline solution with chloramphenicol and sodium azide. Each vial contains sufficient material for at least 25 uses.
**QUANTA Flash aCL IgA Kit:**
1. QUANTA Flash aCL IgA Kit contains one reagent pack (cartridge) with sufficient material for 50 tests. Each reagent pack contains the following sealed reagent tubes:
a. Microparticle Reagent: 1 vial of cardiolipin coated magnetic particles preserved in buffer solution.
b. Assay Buffer: 1 vial of Tris-buffered saline with protein stabilizers and surfactant. Preservatives: sodium azide and chloramphenicol.
c. Tracer IgA: 1 vial of isoluminol conjugated monoclonal anti-human IgA antibodies in phosphate buffered saline with protein (bovine) stabilizer. Preservative: sodium azide.
d. 1 vial of sample diluent used for the regular predilution of the samples and automatic dilution in the rerun.
2. aCL IgA Calibrator 1: 1 x 1 mL barcoded tube of a solution with human anti-aCL IgA in a phosphate buffer, containing bovine serum albumin, stabilizers and preservative. Each vial contains sufficient material for 10 uses.
3. aCL IgA Calibrator 2: 1 x 1 mL barcoded tube of a solution with human anti-aCL IgA in a phosphate buffer, containing bovine serum albumin, stabilizers and preservative. Each vial contains sufficient material for 10 uses.
**QUANTA Flash aCL IgA Control Kit:** Each control kit contains three vials each of Low Control and High Control. Control material contains human antibodies to cardiolipin in a Tris-buffered saline solution with chloramphenicol and sodium azide. Each vial contains sufficient material for at least 25 uses.
For both QUANTA Flash β2GP1 and aCL IgA Kits, the following additional materials are required (available from INOVA Diagnostics, Inc.) but not provided:
a. BIO-FLASH Instrument and Software System
b. BIO-FLASH System Rinse contains four 5 liter bottles of phosphate buffered saline with Tween-20 and sodium azide.
c. BIO-FLASH Triggers contains one bottle each of Trigger 1 (the catalyst) and 2 (the oxidant).
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J. Substantial Equivalence Information:
1. Predicate device name(s) and 510(k) number(s)
QUANTA Lite β2GP1 IgA ELISA, k973006
QUANTA Lite ACA III IgA ELISA, k953366
2. Comparison with predicate:
QUANTA Flash™ β2GP1 IgA
| Similarities | | |
| --- | --- | --- |
| Item | Device
QUANTA Flash β2GP1 IgA | Predicate
QUANTA Lite β2GP1 IgA ELISA |
| Intended Use | Semi-quantitative measurement of anti-β2 glycoprotein-1 (β2GP1) IgA antibodies | Same |
| Coating Antigen | Purified human β2 GP1 | Same |
| Cutoff | 20 CU | Same (20 SAU) |
| Antigen Detected | Human β2GP1 | Same |
| Results | < 20 EU/mL – negative | Same |
| Interpretation | ≥ 20 EU/mL – positive | |
| Differences | | |
| --- | --- | --- |
| Item | Device
QUANTA Flash β2GP1 IgA | Predicate
QUANTA Lite β2GP1 IgA ELISA |
| Indications for Use | Aid in the diagnosis of thrombotic disorders related to primary and secondary antiphospholipid syndrome, when used in conjunction with other laboratory and clinical findings | Used in conjunction with clinical findings and other laboratory tests to aid in the diagnosis of certain autoimmune disease thrombotic disorders, such as those secondary to systemic lupus erythematosus (SLE) or other lupus-like thrombotic diseases |
| Assay Technology | Chemiluminescent Immunoassay (CIA) | Enzyme-linked Immunosorbent Assay (ELISA) |
| Solid phase | Antigen coated magnetic particles | Antigen coated wells |
| Instrumentation | Automated on BIO-FLASH® instrument | Manual |
| Measuring range | 4 – 512 CU | 9.375-150 APL |
| Sample Matrix | Serum and citrated plasma | Serum |
| Conjugate | Isoluminol conjugated monoclonal anti-human IgA | Horseradish peroxidase conjugated goat anti-human IgA |
| Signal Detected | Luminescence (visible light) | Absorbance at 450nm |
| Calibration and unit calculation | Instrument specific working curve based off a 6 point lot specific master curve used for unit calculations; stored on the instrument for the life of the reagent lot | Five point lot specific curve used for unit calculations, run each time the assay is run. |
| Calibrators | Set of 2: ~ 10 and 100 CU | Set of 5: 150, 75, 37.5, 18.75, 9.375 SAU |
QUANTA Flash aCL IgA
| Similarities | | |
| --- | --- | --- |
| Item | Device
QUANTA Flash aCL IgA | Predicate
QUANTA Lite ACA III IgA ELISA |
| Intended Use | Semi-quantitative measurement of anti-cardiolipin (aCL) IgA antibodies | Same |
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| Similarities | | |
| --- | --- | --- |
| Item | Device QUANTA Flash aCL IgA | Predicate QUANTA Lite ACA III IgA ELISA |
| Analyte Detected | Human IgA anti-cardiolipin antibodies | Same |
| Controls | One Cardiolipin IgA Positive Control, one Negative Control | Same |
| Shelf-life | One year | Same |
| Differences | | |
| --- | --- | --- |
| Item | Device QUANTA Flash aCL IgA | Predicate QUANTA Lite ACA III IgA ELISA |
| Indications for Use | Aid in the diagnosis of thrombotic disorders related to primary and secondary anti-phospholipid syndrome (APS), when used in conjunction with other laboratory and clinical findings | Used in conjunction with clinical findings and other laboratory tests to aid in assessing the risk of thrombosis in individuals with systemic lupus erythematosus (SLE) or lupus-like disorders |
| Assay Methodology | Chemiluminescent Immunoassay (CIA) | Enzyme-linked Immunosorbent Assay (ELISA) |
| Solid phase | Antigen coated magnetic particles | Antigen coated wells |
| Instrumentation | Automated on the BIO-FLASH® instrument | Manual |
| Measuring range | 1.4 to 351.6 CU | 9.375-150 APL |
| Sample matrix | Serum and citrated plasma | Serum |
| Coating antigens | Bovine cardiolipin and purified human β2 GP1 | Purified cardiolipin antigen (1,1',2,2' Tetraoleoyl Cardiolipin (sodium salt)) and β2GP1 from human/bovine serum) |
| Conjugate | Isoluminol conjugated monoclonal anti-human IgA | Horseradish peroxidase conjugated goat anti-human IgA |
| Signal detected | Luminescence (visible light) | Absorbance at 450 nm |
| Calibration and unit calculation | Instrument specific working curve based off a 6 point lot specific master curve used for unit calculations; stored on the instrument for the life of the reagent lot. | Five point lot specific curve used for unit calculations, run each time the assay is run. |
| Calibrators | 2 ~ 10 and 80 CU | Set of 5: 150, 75, 37.5, 18.75, 9.375 APL |
| Cutoff | 20 CU | 12 APL |
| Results Interpretation | < 20 EU/mL – negative ≥ 20 EU/mL – positive | < 12 APL – negative 12 – 20 APL – indeterm > 20 APL – positive |
# K. Standard/Guidance Document Referenced (if applicable):
CLSI EP05-A2, Evaluation of Precision Performance of Quantitative Measurement Methods; Approved Guideline, Second Edition.
CLSI EP06-A, Evaluation of the Linearity of Quantitative Measurement Procedures: A Statistical Approach
CLSI EP07-A2, Interference Testing in Clinical Chemistry, Second Edition.
CLSI EP09-A2, Method Comparison and Bias Estimation Using Patient Samples
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EP17-A, Protocols for Determination of Limits of Detection and Limits of Quantification, Approved Guideline.
CLSI EP25-A, Evaluation of Stability of In Vitro Diagnostic Reagents; Approved Guideline
L. Test Principle:
The principles of the QUANTA Flash β2GP1 and aCL IgA assays are similar to other solid phase indirect immunosorbent assays. The assays are a chemiluminescent two-step immunoassay consisting of magnetic particles coated with either human β2GP1 or bovine cardiolipin and human purified β2GP1, which capture, if present either the β2GP1 or the aCL antiphospholipid antibodies from the sample.
The solid phase is paramagnetic beads and the detecting reagent is a mixture of isoluminol-conjugated monoclonal antibodies to human IgA. A patient's serum is diluted with sample dilution buffer in a disposable cuvette. A small amount of this patient dilution is combined with assay buffer and β2GP1 or aCL beads in a second cuvette, and mixed. This reaction cuvette is incubated for 9½ minutes at 37°C. The cuvette is then exposed to a small magnet that holds the beads in place, the liquid is aspirated, and the beads are resuspended as system rinse is added to the cuvette and the magnet is removed. This wash cycle is repeated one more time. During the third wash, no system rinse is added after the aspiration step, rather the isoluminol conjugate (known as Tracer IgA) is added to the beads in the cuvette, and mixed. Again, the cuvette is incubated for 9½ minutes at 37°C. Three wash steps, as described in the first wash step above, are performed on the beads. In the fourth wash step, no liquid is added to the beads after the aspiration.
The cuvette is then placed in a light-tight luminometer and the beads are exposed to a catalyst and an oxidizing agent. These two reagents, or "Triggers", cause the isoluminol to produce a flash of visible light. The light produced from this reaction is measured as Relative Light Units (RLU) by the BIO-FLASH optical system. The RLUs are proportional to the amount of bound isoluminol conjugate, which in turn is proportional to the amount of IgA anti-β2GP1 or anti-aCL antibodies bound to the β2GP1 or cardiolipin on the beads.
The QUANTA Flash β2GP1 and aCL IgA assay utilizes a 4 Parameter Logistic Curve (4PLC) fit data reduction method to generate a Master Curve. The Master Curve is predefined, lot dependent and it is uploaded to the instrument through the reagent cartridge barcode. With the measurement of calibrators, the predefined Master Curve is transformed to a new, instrument specific Working Curve. The concentration values of the calibrators are included in the calibrator tube barcodes.
M. Performance Characteristics (if/when applicable):
1. Analytical performance:
a. Precision/Reproducibility:
Precision of the QUANTA Flash™ β2GP1 and aCL IgA assays was assessed in accordance with CLSI EP5-A2 document, by running 11-12 serum samples from different parts of the claimed assay ranges in duplicate with two runs per day for at least 20 days (some samples were run for 21 days) for a minimum of 80
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measurements (N) per sample. Within-run (repeatability), between-run, between-day and total precision were calculated by the Analyse-it for Excel software. The results are summarized in the tables below:
QUANTA Flash™ β2GP1 IgA:
| Sample | N | Mean (CU) | Within-Run (Repeatability) | | Between-Run | | Between-Day | | Total | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 1 | 84 | 412.3 | 27.4 | 6.7% | 26.4 | 6.4% | 21.2 | 5.1% | 43.6 | 10.6% |
| 2 | 80 | 113.8 | 4.9 | 4.3% | 8.6 | 7.6% | 6.1 | 5.3% | 11.6 | 10.2% |
| 3 | 80 | 109.6 | 4.3 | 3.9% | 6.9 | 6.3% | 12.1 | 11.0% | 14.6 | 13.3% |
| 4 | 84 | 27.7 | 1.2 | 4.5% | 2.3 | 8.3% | 1.5 | 5.4% | 3.0 | 10.9% |
| 5 | 80 | 8.3 | 0.9 | 11.4% | 0.7 | 8.7% | 0.1 | 1.1% | 1.2 | 14.4% |
| 6 | 80 | 7.3 | 1.1 | 15.3% | 0.0 | 0.0% | 0.8 | 11.4% | 1.4 | 19.1% |
| 7 | 80 | 18.6 | 0.6 | 3.0% | 1.2 | 6.7% | 0.4 | 2.2% | 1.4 | 7.6% |
| 8 | 80 | 23.1 | 0.6 | 2.7% | 1.2 | 5.1% | 0.0 | 0.9% | 1.3 | 5.8% |
| 9 | 80 | 20.7 | 0.6 | 2.7% | 0.5 | 2.2% | 0.8 | 4.0% | 1.1 | 5.3% |
| 10 | 80 | 21.2 | 0.4 | 2.0% | 0.8 | 3.5% | 0.8 | 3.7% | 1.2 | 5.5% |
| 11 | 80 | 433.4 | 23.3 | 5.4% | 18.7 | 3.4% | 28.9 | 6.7% | 41.6 | 9.6% |
QUANTA Flash™ aCL IgA:
| Sample | N | Mean (CU) | Within-Run (Repeatability) | | Between-Run | | Between-Day | | Total | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 1 | 84 | 247.42 | 12.6 | 4.9% | 6.4 | 2.6% | 21.9 | 8.9% | 25.9 | 10.5% |
| 2 | 84 | 98.7 | 2.34 | 2.4% | 3.54 | 3.6% | 6.8 | 6.9% | 8.1 | 8.2% |
| 3 | 80 | 52.7 | 1.6 | 3.0% | 2.7 | 5.1% | 3.0 | 5.8% | 4.3 | 8.2% |
| 4 | 80 | 24.0 | 1.1 | 4.7% | 1.3 | 5.5% | 1.5 | 6.4% | 2.3 | 9.7% |
| 5 | 80 | 3.9 | 0.3 | 8.5% | 0.0 | 9.4% | 0.3 | 7.0% | 0.6 | 14.9% |
| 6 | 80 | 6.9 | 0.9 | 13.4% | 0.9 | 13.4% | 0.9 | 12.4% | 1.6 | 22.7% |
| 7 | 80 | 2.0 | 0.3 | 13.7% | 0.3 | 14.8% | 0.0 | 5.8% | 0.4 | 21.0% |
| 8 | 80 | 18.9 | 0.6 | 3.2% | 0.5 | 2.6% | 0.7 | 3.5% | 1.0 | 5.4% |
| 9 | 80 | 16.5 | 0.4 | 2.3% | 0.7 | 4.2% | 0.2 | 1.2% | 0.8 | 5.0% |
| 10 | 80 | 23.4 | 2.2 | 9.4% | 1.5 | 6.4% | 0.0 | 0.0% | 2.7 | 11.4% |
| 11 | 80 | 23.1 | 0.7 | 3.2% | 0.9 | 3.8% | 0.3 | 1.3% | 1.2 | 5.1% |
| 12 | 80 | 287.7 | 16.1 | 5.6% | 0.0 | 0.0% | 24.3 | 8.4% | 29.1 | 10.1% |
Lot-to-lot Reproducibility: Patient samples were tested using three different lots of QUANTA Flash β2GP1 or aCL IgA reagent cartridges. Nine patient samples were each tested once across three different production lots and three instruments for a total of nine measurements. An additional two samples close to the cutoff were tested in a separate experiment in duplicate on three different instruments across two lots. Results are summarized below:
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QUANTA Flash™ β2GP1 IgA
| Sample | Mean (CU) | Lot 1 | | Lot 2 | | Lot 3 | | Lot-to-Lot Variation | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Pt 1 | 50.9 | 5.5 | 10.6% | 3.7 | 7.4% | 2.4 | 4.8% | 0.5 | 1.1% |
| Pt 2 | 92.4 | 5.0 | 5.6% | 6.4 | 6.7% | 6.0 | 6.5% | 3.3 | 3.6% |
| Pt 3 | 48.5 | 6.2 | 12.9% | 2.8 | 5.8% | 1.5 | 3.1% | 0.1 | 0.3% |
| Pt 4 | 13.5 | 2.5 | 20.4% | 0.5 | 3.9% | 0.4 | 3.0% | 0.9 | 6.6% |
| Pt 5 | 4.0 | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% |
| Pt 6 | 125.1 | 5.6 | 4.5% | 14.9 | 11.8% | 6.7 | 5.3% | 1.3 | 1.0% |
| Pt 7 | 68.7 | 5.1 | 7.6% | 7.8 | 11.2% | 1.3 | 1.9% | 1.8 | 2.6% |
| Pt 8 | 82.3 | 6.5 | 7.8% | 6.2 | 7.4% | 2.0 | 2.6% | 2.0 | 2.5% |
| Pt 9 | 60.3 | 4.8 | 7.9% | 3.9 | 6.4% | 1.7 | 2.8% | 1.1 | 1.8% |
| Pt 10 | 19.3 | 0.68 | 3.5% | 1.4 | 7.1% | ND | ND | 0.32 | 1.6% |
| Pt 11 | 20.9 | 1.54 | 7.1% | 1.5 | 7.4% | ND | ND | 1.02 | 4.9% |
ND not tested
QUANTA Flash™ aCL IgA
| Sample | Mean (CU) | Lot 1 | | Lot 2 | | Lot 3 | | Lot-to-Lot Variation | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Pt 1 | 118.5 | 11.9 | 10.1% | 6.7 | 5.7% | 7.8 | 6.4% | 2.3 | 1.9% |
| Pt 2 | 86.2 | 4.5 | 5.5% | 3.8 | 4.6% | 2.4 | 2.6% | 6.7 | 7.7% |
| Pt 3 | 39.2 | 2.0 | 5.3% | 0.7 | 1.7% | 0.3 | 0.6% | 1.9 | 4.8% |
| Pt 4 | 12 | 0.8 | 6.4% | 0.4 | 3.3% | 0.4 | 3.0% | 0.4 | 3.1% |
| Pt 5 | 5 | 0.4 | 8.5% | 0.2 | 2.9% | 0.2 | 3.5% | 0.3 | 5.3% |
| Pt 6 | 101.4 | 6.0 | 6.3% | 3.2 | 3.2% | 1.0 | 0.9% | 7.8 | 7.7% |
| Pt 7 | 54.3 | 2.5 | 4.9% | 2.1 | 3.9% | 0.3 | 0.5% | 3.3 | 6.0% |
| Pt 8 | 58.5 | 3.2 | 5.4% | 1.7 | 2.8% | 3.8 | 6.6% | 0.6 | 1.0% |
| Pt 9 | 43.6 | 2.0 | 4.7% | 1.1 | 2.5% | 1.1 | 2.6% | 0.2 | 0.4% |
| Pt 10 | 17.3 | 0.56 | 3.2% | 1.2 | 7.2% | ND | ND | 0.58 | 3.4% |
| Pt 11 | 21.3 | 0.83 | 3.8% | 1.8 | 7.5% | ND | ND | 0.66 | 3.1% |
ND not tested
b. Linearity/assay reportable range:
The QUANTA Flash™ β2GP1 and aCL IgA assay linearity studies were evaluated in accordance with CLSI EP6-A Guideline. For each assay, 9 serum samples with various β2GP1 IgA or aCL IgA concentrations were diluted by combining the positive serum sample with the negative serum sample. The observed values were graphed against the calculated values and linear regression was performed. The study results are summarized in the tables below:
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QUANTA Flash™ β2GP1 IgA:
| Sample | Test Range (CU) | Slope (95% CI) | Y-Intercept (95% CI) | R² |
| --- | --- | --- | --- | --- |
| 1 | 51.2 to 512.0 | 0.98
(0.93 to 1.03) | -4.44
(-20.31 to 11.43) | 1.00 |
| 2 | 21.2 to 212.4 | 0.95
(0.86 to 1.04) | -3.78
(-16.87 to 9.32) | 0.99 |
| 3 | 20.4 to 204.6 | 0.97
(0.92 to 1.01) | 8.65
(3.65 to 13.66) | 1.00 |
| 4 | 12.8 to 128.1 | 0.96
(0.89 to 1.02) | 5.68
(0.36 to 11.01) | 0.99 |
| 5 | 7.5 to 74.7 | 1.00
(0.78 to 1.22) | -11.21
(-23.36 to 0.94) | 0.93 |
| 6 | 1.9 to 19.3 | 1.32
(1.09 to 1.56) | -7.91
(-11.31 to -4.51) | 0.96 |
| 7 | 2.2 to 21.9 | 0.95
(0.88 to 1.01) | 0.72
(-0.2 to 1.64) | 0.98 |
| 8 | 2.1 to 20.7 | 0.96
(0.88 to 1.04) | 0.018
(-0.97 to 1.01) | 0.97 |
| 9 | 3.17 to 31.7 | 0.99
(0.95 to 1.03) | -0.56
(-1.30 to 0.19) | 0.99 |
The reportable range of the assay is defined by the lowest and highest points on the master calibration curve. The claimed reportable range for the QUANTA Flash™ β2GP1 IgA assay is from 4 CU to 512 CU.
QUANTA Flash™ aCL IgA:
| Sample | Test Range (CU) | Slope (95% CI) | Y-Intercept (95% CI) | R² |
| --- | --- | --- | --- | --- |
| 1 | 35.2 to 351.6 | 1.00
(0.95 to 1.05) | -1.10
(-12.70 to 10.50) | 1.00 |
| 2 | 17.1 to 171.0 | 0.93
(0.83 to 1.04) | -4.92
(-17.38 to 7.54) | 0.98 |
| 3 | 15.9 to 158.7 | 0.94
(0.91 to 0.98) | 5.32
(1.97 to 8.67) | 1.0 |
| 4 | 10.3 to 103.5 | 0.95
(0.93 to 0.98) | 3.00
(1.07 to 4.92) | 1.0 |
| 5 | 4.7 to 46.7 | 0.97
(0.76 to 1.17) | -6.78
(-14.13 to 0.57) | 0.94 |
| 6 | 1.6 to 16.4 | 1.03
(0.93 to 1.13) | -1.41
(-2.56 to -0.267) | 0.98 |
| 7 | 2.3 to 22.7 | 1.01
(0.93 to 1.07) | -0.25
(-1.24 to 0.732) | 0.98 |
| 8 | 1.4 to 14.3 | 1.09
(1.01 to 1.16) | -1.11
(-1.17 to -0.46) | 0.98 |
| 9 | 3.3 to 33.5 | 1.05
(1.03 to 1.07 | -1.71
(-2.12 to -1.31) | 1.00 |
The reportable range of the assay is defined by the lowest and highest points on the master calibration curve. The claimed reportable range for the QUANTA Flash™ aCL IgA assay is from 1.4 CU to 351.6 CU.
{9}
c. Traceability, Stability, Expected values (controls, calibrators, or methods):
Traceability:
There is no international or certified reference material available for anti-β2 GP1 or anti-αCL antibodies. The assay is calibrated in relative arbitrary units (CU or U/mL).
Value Assignment:
Control and calibrator materials are manufactured from human serum containing high-titer IgA anti-β2 GP1 antibodies or IgA anti-αCL antibodies obtained from commercially available sources.
The calibrators included in the QUANTA Flash β2 GP1 and QUANTA Flash αCL IgA assays utilize a predefined lot-specific Master Curve that is stored in the reagent pack barcode. The two calibrator values are assigned using in-house standards and a four-parameter master curve. The assignment values of the two calibrators are used to create a lot-specific four-parameter logistic curve, using two stored parameters from the Master Curve and two lot-specific parameters based on the calibrator values.
The QUANTA Flash β2 GP1 IgA Controls and QUANTA Flash αCL IgA Controls are also manufactured by diluting human serum containing high-titer IgA anti-β2 GP1 antibodies or IgA anti-αCL antibodies into buffer. A target CU value is achieved through trial dilutions on a small scale. Once a dilution is selected, the control is bulked, tested, and adjusted. Controls are tested on at least two instruments, on at least two lots of reagent cartridge, in replicates of 10 to determine final value assignment.
Stability:
Stability studies have been performed to support the following claims:
Reagent Pack Stability:
Shelf-life: The reagent pack can be stored, unopened, at 2–8°C for 1 year based on accelerated stability testing (2 weeks at 37°C). Real time stability is ongoing.
Open/On-board/In-use Stability: Opened reagent packs must be stored on-board the instrument. The working curve has been demonstrated to remain stable for 64 days.
Calibrators Stability:
Shelf-Life: Calibrators showed acceptable accelerated stability for 2 weeks at 37°C, translating to at least 1 year of storage at 2–8°C. Real time stability is ongoing.
On-board Stability: On-board stability testing supported that the calibrators may be stored open for up to 8 hours onboard the instrument.
Control Stability:
Shelf-Life: Controls showed acceptable accelerated stability for 2 weeks at 37°C, translating to at least 1 year of storage at 2–8°C. Real time stability is ongoing.
10
{10}
On-board Stability: Open controls may be used up to 15 times, with a maximum of 10 minutes on-board the instrument per use. The total time the control tubes can be used is 2.5 hours or 10 minutes per use.
d. Detection limit:
Limit of Blank (LoB):
For the QUANTA Flash β2GP1 IgA and QUANTA Flash aCL IgA assays, the LoB was determined according to EP17-A by running immunoglobulin stripped serum diluted at the working dilution of 1:5 run twice in replicates of 30 to obtain 60 measurements.
For the QUANTA Flash β2GP1 IgA assay the LoB was determined to be 412 RLU and for the QUANTA Flash aCL IgA assay the LoB was determined to be 561 RLU. The LoB values for both assays are below the bottom limit of the 4 parameter logistic curve that the instrument uses to calculate chemiluminescent units (CU), and therefore cannot be converted into CU.
Limits of Detection (LoD):
For both devices, the LoD was determined using five serum samples that were serially diluted until the RLU values no longer show a decreasing trend. The dilution factor that gave a RLU value that is noticeably above that background noise was chosen for each serum. A direct dilution using that dilution factor was made for each serum so they were used as the low-level samples that are in between the LoB to approximately 4 x LoB. These 5 samples were run in replicates of 4 for 4 days; 2 days on 1 instrument and 2 more days on another instrument to obtain 16 measurements per sample for a total 80 measurements. It was determined consistent with CLSI EP17-A with proportions of false positives (alpha) less than 5% and false negatives (beta) less than 5%. The LoD for each assay is below the lower limit of the reportable range.
For the QUANTA Flash β2GP1 IgA assay the LoD was determined to be 522 RLU and for the QUANTA Flash aCL IgA assay the LoB was determined to be 812 RLU. The LoD values for both assays are below the bottom limit of the 4 parameter logistic curve (CU)(4850 RLU and 4400 RLU for β2GP1 and aCL respectively) that the instrument uses to calculate chemiluminescent units, and therefore cannot be converted into CU. The LoD for each assay is below the lower limit of the reportable range.
e. Analytical specificity:
Interfering Substances:
Four β2GP1 IgA and aCL IgA serum samples with different analyte concentrations (negative, positive and two around cutoff) were mixed with known quantities of hemoglobin (2, 1, 0.5 mg/mL), bilirubin (1, 0.5, 0.25 mg/mL), cholesterol (224, 112, 56 mg/dL) triglycerides (1000, 500, 250 mg/dL) or rheumatoid factor (about 500, 300, or 100 IU/mL) or buffer. The sera were run in triplicate. The average percent recovery at each dilution is calculated.
11
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No interference was observed up to the concentrations listed in the table below:
| Potential Interferent | Final Concentration Tested |
| --- | --- |
| Hemoglobin | 200 mg/dL |
| Bilirubin | 100 mg/dL |
| Cholesterol | 224 mg/dL |
| Triglycerides | 1000 mg/dL |
| Rheumatoid Factor | 500 IU/mL |
A statement indicating that lipemic and/or grossly hemolyzed sera should not be used is included in the direction insert.
## Cross-Reactivity:
A study separate from the clinical sample population was used to determine cross reactivity. Seventy-nine (79) patient samples with various antibodies to autoimmune or infectious diseases were tested in the QUANTA Flash™ β2 GP1 and aCL IgA assays. For infectious disease, samples tested included CMV (5), HCV (5), rubella (5), toxoplasmosis (2), and HSV (5). For the other autoimmune disease states, samples from patients with the following antibodies were tested: 10 rheumatoid factor (RF), 9 anti-cyclic citrullinated peptide (CCP), 8 anti-myeloperoxidase (MPO), and 30 extractable nuclear antibodies (ENA). No cross-reactivity was observed
## High dose hook effect:
To assess high dose hook effect, two high positive samples above the reportable ranges were used neat or manually diluted 1:2, 1:4, 1:3 and 1:5 and assayed on both the QUANTA Flash β2GP1 IgA assay and the QUANTA Flash aCL IgA assay
Since these samples ran above the top of the standard curve, standard protocol of the machine is to report results as >351.6 for aCL IgA and >512 CU for β2GP1 IgA. A formula was used to calculate higher values. Results for β2GP1 IgA, no hook effect was demonstrated up to 823.4 and 1436.0 CU, respectively. Results for aCL IgA, no hook effect was demonstrated up to 917.7 and 1033.0 CU, respectively.
## f. Assay cut-off:
224 patient samples were tested on the QUANTA Flash β2GP1 IgA and QUANTA Flash aCL IgA devices. The sample cohort consisted of 196 apparently normal healthy blood donors and 28 HCV antibody positive samples. To establish the cutoff, CLSI C28-A3C was followed along with recommendations of the International Committee in Sydney that the cutoff between negative and positive for anti-phospholipid antibodies should be >99% of a normal population. As a result, the cut-off for both assays was set to 20.0 U/mL. A result below 20.0 U/mL is considered negative, while 20.0 or greater is considered positive.
## 2. Comparison studies:
a. Method comparison with predicate device:
{12}
Samples for method comparison analysis included those samples from the clinical validation study that were within the reportable range of the assays. For the first set of tables for each analyte, only samples within the measuring ranges defined by the lowest and highest calibrators of both the QUANTA Flash and predicate assays are included in this method comparison. This comparison included 148 total patient samples for the QUANTA Flash $\beta 2\mathrm{GP}1$ IgA and 99 samples for QUANTA Flash aCL IgA. The predicate for the QUANTA Flash aCL IgA has an indeterminate zone so data are also analyzed using the intermediate results as positive or negative. Agreement for the entire validation set $(n = 632)$ including samples above or below the assay measuring ranges for each assay are also presented below.
QUANTA Flash β2GP1 IgA:
| Samples within both assay measuring ranges (n=148) | Predicate β2GP1 IgA ELISA (9.4 -150 SAU) | | | |
| --- | --- | --- | --- | --- |
| | | Positive > 20 SAU | Negative < 20 SAU | Total |
| QUANTA Flash β2GP1 IgA (4 - 512 CU) | Positive > 20 CU | 63 | 28* | 91 |
| | Negative <20 CU | 18** | 39 | 57 |
| | Total | 81 | 67 | 148 |
*9APS, 4 PAPS, 11 SAPS, 4 SLE.
**7APS, 1PAPS, 7 SAPS, 1 RA, 2 SLE.
Positive Percent Agreement (63/81): $77.8\%$ (95% CI: 67.2-86.3%)
Negative Percent Agreement (39/67): $58.2\%$ (95% CI: 45.5-70.2%)
Overall Percent Agreement (102/148): $68.9\%$
| All samples in Clinical/Validation set (n=632) | Predicate β2GP1 IgA ELISA (9.4 -150 SAU) | | | |
| --- | --- | --- | --- | --- |
| | | Positive > 20 SAU | Negative < 20 SAU | Total |
| QUANTA Flash β2GP1 IgA (4 - 512 CU) | Positive > 20 CU | 71 | 39* | 110 |
| | Negative <20 CU | 38** | 484 | 522 |
| | Total | 109 | 523 | 632 |
*35 APS, 4 SLE.
**23 APS, 1 snAPS, 1 RA, 9 infectious, 4 SLE.
Positive Percent Agreement (71/109): $65.1\%$ (95% CI: 55.4-74.0%)
Negative Percent Agreement (484/523): $92.5\%$ (95% CI: 89.9-94.6%)
Overall Percent Agreement (555/632): $87.8\%$
{13}
QUANTA Flash aCL IgA:
| Samples within both assay measuring ranges (n=99) | Predicate aCL IgA ELISA (9.4 – 150 APL) | | | | |
| --- | --- | --- | --- | --- | --- |
| | | Positive (>20 APL) | Borderline (12–20 APL) | Negative (< 12 APL) | Total |
| QUANTA Flash aCL IgA (1.4 – 351.6 CU) | Positive (>20 CU) | 23 | 21 | 8* | 52 |
| | Negative (<20 CU) | 8** | 18 | 21 | 47 |
| | Total | 31 | 39 | 29 | 99 |
*6 APS and 2 SLE
**6 APS, 1 SLE and 1 SLE-like
| Samples within both assay measuring ranges
Intermediate samples excluded (n=60) | Predicate aCL IgA ELISA | | | |
| --- | --- | --- | --- | --- |
| | | Positive (>20 APL) | Negative (< 12 APL) | Total |
| QUANTA Flash aCL IgA | Positive (>20 CU) | 23 | 8* | 31 |
| | Negative (<20 CU) | 8** | 21 | 29 |
| | Total | 31 | 29 | 60 |
*6 APS and 2 SLE
** 6 APS, 1 SLE, 1 SLE-like
Positive Percent Agreement (23/31): 74.2% (95% CI: 55.4–88.1%)
Negative Percent Agreement (21/29): 72.4% (95% CI: 52.8–87.3%)
Overall Percent Agreement (44/60): 73.3%
| Samples within both assay measuring ranges
Borderline Samples for Predicate Considered Positive (>12) (n=99) | Predicate aCL IgA ELISA | | | |
| --- | --- | --- | --- | --- |
| | | Positive (>12 APL) | Negative (< 12 APL) | Total |
| QUANTA Flash aCL IgA | Positive (>20 CU) | 44 | 8* | 52 |
| | Negative (<20 CU) | 26** | 21 | 47 |
| | Total | 70 | 29 | 99 |
*6 APS and 2 SLE
** 17 APS, 7 SLE, 1 SLE-like, 1 RA
Positive Percent Agreement (44/70): 62.9% (95% CI: 50.5%–74.1%)
Negative Percent Agreement (21/29): 72.4% (95% CI: 52.8–87.3%)
Overall Percent Agreement (65/99): 65.6%
14
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15
| Samples within both assay measuring ranges Borderline Samples for Predicate Considered Negative (< 20) (n=99) | Predicate aCL IgA ELISA | | | |
| --- | --- | --- | --- | --- |
| | | Positive (>20 APL) | Negative (< 20 APL) | Total |
| QUANTA Flash aCL IgA | Positive (>20 CU) | 23 | 29* | 52 |
| | Negative (<20 CU) | 8** | 39 | 47 |
| | Total | 31 | 68 | 99 |
* 24 APS, 5 SLE
**6 APS, 1 SLE and 1 SLE-like
Positive Percent Agreement (23/31): 74% (95% CI: 55.4% - 88.1%)
Negative Percent Agreement (39/68): 57.4% (95% CI: 44.8% - 69.3%)
Overall Percent Agreement (62/99): 62.6%
| All samples
In Clinical/Validation set (n=632) | Predicate aCL IgA ELISA
(9.4 – 150 APL) | | | | |
| --- | --- | --- | --- | --- | --- |
| | | Positive (>20 APL) | Borderline (12–20 APL) | Negative (< 12 APL) | Total |
| QUANTA Flash
aCL IgA
(1.4 – 351.6 CU) | Positive | 29 | 21 | 52* | 102 |
| | Negative | 12** | 26 | 492 | 530 |
| | Total | 41 | 47 | 544 | 632 |
* 46 APS, 4 SLE, 1 RA, 1 other Rheumatic Disease
** 8 APS, 2 RA, 1 SLE, 1 SLE-like
| All samples
In Clinical/Validation set
Indeterminate samples excluded (n=585) | Predicate aCL IgA ELISA
(9.4 – 150 APL) | | | |
| --- | --- | --- | --- | --- |
| | | Positive (>20 APL) | Negative (< 12 APL) | Total |
| QUANTA Flash
aCL IgA
(1.4 – 351.6 CU) | Positive (>20 CU) | 29 | 52* | 81 |
| | Negative (<20 CU) | 12** | 492 | 504 |
| | Total | 41 | 544 | 585 |
*46 APS, 4 SLE, 1 RA, 1 other Rheumatic Disease
** 8 APS, 2 RA, 1 SLE, 1 SLE-like
Positive Percent Agreement (29/41): 71% (95% CI: 54.5–83.9%)
Negative Percent Agreement (492/544): 90% (95% CI: 87.7–92.8%)
Overall Percent Agreement (521/585): 89%
| All samples In Clinical/Validation set (n=632)
Borderline Samples for Predicate Considered Negative (< 20) | Predicate aCL IgA ELISA
(9.4 – 150 APL) | | | |
| --- | --- | --- | --- | --- |
| | | Positive (>20 APL) | Negative (< 20 APL) | Total |
| QUANTA Flash
aCL IgA
(1.4 – 351.6 CU) | Positive (>20 CU) | 29 | 73* | 102 |
| | Negative (<20 CU) | 12** | 518 | 530 |
| | Total | 41 | 591 | 632 |
{15}
*64 APS, 7 SLE, 1 RA, 1 Other Rheumatic Disease
** 8 APS, 2 RA, 1 SLE, 1 SLE-like
Positive Percent Agreement (29/41): 70.7% (95% CI: 54.5–83.9%)
Negative Percent Agreement (518/591): 87.6% (95% CI: 84.7–90.2%)
Overall Percent Agreement (547/632): 86.5%
| All samples In Clinical/Validation set (n=632) Borderline Samples for Predicate Considered Positive (>12) | Predicate aCL IgA ELISA (9.4 – 150 APL) | | | |
| --- | --- | --- | --- | --- |
| | | Positive (>12 APL) | Negative (< 12 APL) | Total |
| QUANTA Flash aCL IgA (1.4 – 351.6 CU) | Positive (>20 CU) | 50 | 52* | 102 |
| | Negative (<20 CU) | 38** | 492 | 530 |
| | Total | 88 | 544 | 632 |
*46 APS, 4 SLE, 1 RA, 1 Other Rheumatic Diseases
** 22 APS, 3 RA, 8 SLE, 1 SLE-like, 1 syphilis, 1 seronegative SAPS, 1 HCV, 1 HBV
Positive Percent Agreement (50/88): 56.8% (95% CI: 45.8–67.3%)
Negative Percent Agreement (492/544): 90.4% (95% CI: 87.7–92.8%)
Overall Percent Agreement (542/632): 85.8%
## b. Matrix comparison:
A matrix comparison study was performed for the QUANTA Flash β2GP1 IgA and QUANTA Flash aCL IgA assays using 42 paired serum and sodium-citrate plasma blood draws for β2GP1 IgA and 49 serum-plasma pairs for aCL IgA. Both sets of samples were within the analytical measuring range of the assays with samples ranging from 4 to 456 CU for β2GP1 IgA and for 1.7 to 329 CU for aCL IgA.
The resulting data support the package insert claim that serum and Na-citrated plasma primary tube specimens are acceptable sample types for use with the QUANTA Flash IgA assays. Results are summarized in table below:
QUANTA Flash β2GP1 IgA:
| Sodium Citrate vs. Serum | | Passing/Bablok |
| --- | --- | --- |
| | N | 49 |
| | Range (CU) | 4.1 – 456.1 CU |
| | Slope | 1.01 |
| | Y intercept | 0.89 |
| | Correlation coefficient (τ) | 0.979 |
QUANTA Flash aCL IgA:
| Sodium Citrate vs. Serum | | Passing/Bablok |
| --- | --- | --- |
| | N | 42 |
| | Range (CU) | 1.7 – 329 CU |
| | Slope | 1.10 |
| | Y intercept | -2.74 |
| | Correlation coefficient (τ) | 0.993 |
{16}
# 3. Clinical studies:
# a. Clinical Sensitivity and Specificity:
The validation set consisted of sent of clinically characterized sera from Primary APS, Secondary APS and non-APS diseased controls for a total of 632 patient samples, none of which were used in the training set. The same validation set was used on both IgA aCL and IgA $\beta 2\mathrm{GP1}$ . The results of the QUANTA Flash $\beta 2\mathrm{GP1}$ IgA and QUANTA Flash aCL IgA devices in each disease category are shown below:
| APS Patient Sub-Group | N | QUANTA Flash β2GP1 IgA % Positive (N) | QUANTA Flash aCL IgA % Positive (N) |
| --- | --- | --- | --- |
| Primary APS (PAPS) | 85 | 22.4% (19) | 21.2% (18) |
| Secondary APS (SAPS) | 139 | 36.7% (51) | 36.0% (50) |
| APS not classified as SAPS or PAPS | 65 | 41.5% (27) | 35.4% (23) |
| Total APS | 289 | 33.2% (97) | 31.5% (91) |
| Non-APS Patient Group | N | QUANTA Flash β2GP1 IgA % Positive (N) | QUANTA Flash aCL IgA % Positive (N) |
| --- | --- | --- | --- |
| SLE | 119 | 9.2% (11) | 7.6% (9) |
| APS-like | 79* | 1.3% (1) | 1.3% (1) |
| Rheumatoid Arthritis | 49 | 2.0% (1) | 2.0% (1) |
| Sjögren's Syndrome | 16 | 0% (0) | 0% (0) |
| Autoimmune Thyroiditis | 3 | 0% (0) | 0% (0) |
| Infectious Diseases | 77** | 0% (0) | 0% (0) |
| Total | 343 | 3.8% (13) | 3.2% (11) |
*68 have APS symptoms and 11 have non-APS thrombotic disorders
**2 HSV,1 Lyme disease,2 Rubella,1 CMV,1 Toxoplasmosis, 9 Syphilis, 10 HIV, 21 HCV, 30
HBV
The clinical sensitivity and specificity of the QUANTA Flash $\beta 2\mathrm{GP1}$ IgA and the QUANTA Flash aCL IgA assays are summarized with and without the SLE group in the following table:
| Disease | QUANTA Flash β2GP1 IgA | | QUANTA Flash aCL IgA | |
| --- | --- | --- | --- | --- |
| | Clinical Sensitivity (95% CI) | Clinical Specificity (95%CI) | Clinical Sensitivity (95% CI) | Clinical Specificity (95%CI) |
| Primary APS (PAPS) | 22.4% (14.0–32.7%) | 96.2% (93.6–98.0%) 99.1%* (96.8–99.9%) | 21.2% (13.1–31.4%) | 96.8% (94.3–98.4%) 99.1%* (96.8–99.9%) |
| Secondary APS (SAPS) | 36.7% (28.7–45.3%) | 96.2% (93.6–98.0%) 99.1%* (96.8–99.9%) | 36.0% (28.0–44.5%) | 96.8% (94.3–98.4%) 99.1%* (96.8–99.9%) |
| APS not classified as SAPS or PAPS | 41.5% (29.4–54.4%) | 96.2% (93.6–98.0%) 99.1%* (96.8–99.9%) | 35.4% (23.9–48.2%) | 96.8% (94.3–98.4%) 99.1%* (96.8–99.9%) |
{17}
| Disease | QUANTA Flash β2GP1 IgA | | QUANTA Flash aCL IgA | |
| --- | --- | --- | --- | --- |
| | Clinical Sensitivity (95% CI) | Clinical Specificity (95%CI) | Clinical Sensitivity (95% CI) | Clinical Specificity (95%CI) |
| Total APS | 33.6% (28.1–39.3%) | 96.2% (93.6–98.0%)
99.1%* (96.8–99.9%) | 31.5% (26.2–37.2%) | 96.8% (94.3–98.4%)
99.1%* (96.8–99.9%) |
*Specificity without SLE population
b. Other clinical supportive data (when a. is not applicable): Not applicable.
4. Clinical cut-off:
See Assay Cutoff
5. Expected values/Reference range:
The expected value in the general population is negative. The normal range was established by testing a population of normal blood donor serum specimens and tested on the QUANTA Flash β2GP1 IgA and QUANTA Flash aCL IgA assays. Results demonstrating incidence in the apparently-disease free samples for this study are provided below:
| | | QUANTA Flash β2GP1 IgA | | QUANTA Flash aCL IgA | |
| --- | --- | --- | --- | --- | --- |
| Normal Blood Donors | n | % pos | n | % pos | n |
| | 359 | 0.56% | 2 | 0.56% | 2 |
N. Proposed Labeling:
The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.
O. Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.
