BioPlex 2200 Lyme Total

{0} 1 # 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY A. 510(k) Number: K183446 B. Purpose for Submission: To obtain a substantial equivalence determination and FDA clearance for a new device C. Measurand: Anti-Borrelia burgdorferi (IgM and/or IgG) antibodies D. Type of Test: Enzyme Immunoassay E. Applicant: Bio-Rad Laboratories F. Proprietary and Established Names: BioPlex 2200 Lyme Total ## G. Regulatory Information: 1. Regulation section: 21 CFR 866.3830; Treponema pallidum treponemal test reagents 2. Classification: Class II 3. Product code: LSR; Reagent, Borrelia Serological Reagent 4. Panel: Microbiology ## H. Intended Use: 1. Intended use(s): The BioPlex 2200 Lyme Total kit is a multiplex flow immunoassay intended for the qualitative detection of total (IgM/IgG) antibodies to Borrelia burgdorferi in human serum and plasma (EDTA, heparin). This assay should be used to test patients with history and/or symptoms of infection with B. burgdorferi. The BioPlex 2200 Lyme Total kit is intended for use with the Bio-Rad BioPlex 2200 System. All reactive and equivocal specimens should be tested with a second tier test such as Lyme IgG and IgM Western blot assays. Positive second tier results are supportive evidence of infection with B. burgdorferi. Diagnosis of Lyme borreliosis should be made based on the presence of B. burgdorferi antibodies, history, symptoms, and other laboratory data. Non-reactive first tier or negative second tier results should not be used to exclude borreliosis. 2. Indication(s) for use: Same as Intended Use 3. Special conditions for use statement(s): N/A 4. Special instrument requirements: BioPlex 2200 System {1} # I. Device Description: The BioPlex 2200 Lyme Total kit employs fluoromagnetic, dyed beads which are coated with recombinant p58, OspCB or synthetic peptide FVlsE (consisting of FlaB and VlsE sequences). Unique fluorescent signatures identify the presence of total (IgG/IgM) antibodies to $B$ . burgdorferi in a two-step assay format. The BioPlex 2200 System combines an aliquot of patient sample, sample diluent, and bead reagent in a reaction vessel. The mixture is incubated at $37^{\circ}\mathrm{C}$ . After a wash cycle, a mixture of murine monoclonal anti-human IgG and murine monoclonal anti-human IgM antibody conjugated to phycoerythrin (PE) is added to the dyed beads, and this mixture is incubated at $37^{\circ}\mathrm{C}$ . The excess conjugate is removed in another wash cycle and the beads are re-suspended in sheath fluid. The bead mixture then passes through the detector. The identity of the dyed beads is determined by the fluorescence of the dyes, and the amount of antibody captured by the antigen is determined by the fluorescence of the attached PE. Raw data is calculated in relative fluorescence intensity (RFI). # J. Substantial Equivalence Information: 1. Predicate device name(s): Immunetics C6 B. burgdorferi (Lyme) ELISA Kit 2. Predicate 510(k) number(s): K003754 3. Comparison with predicate: Table 1: Similarities and Differences with the Predicate | Similarities | | | | --- | --- | --- | | Item | Device BioPlex 2200 Lyme Total | Predicate C6 B. burgdorferi (Lyme) ELISA Kit (K003754) | | Intended Use | The BioPlex 2200 Lyme Total kit is a multiplex flow immunoassay intended for the qualitative detection of total (IgM/IgG) antibodies to Borrelia burgdorferi in human serum and plasma (EDTA, heparin). This assay should be used to test patients with history and/or symptoms of infection with B. burgdorferi. The BioPlex 2200 Lyme Total kit is intended for use with the Bio-Rad BioPlex 2200 System. All reactive and equivocal specimens should be tested with a second tier test such as Western blot. Positive second tier results are supportive evidence of infection | The Immunetics C6 B. burgdorferi (Lyme) ELISA Kit is intended for use in the presumptive detection of IgG and IgM antibodies to B. burgdorferi in human serum. The assay should be used only on samples from patients with clinical history, signs or symptoms consistent with B. burgdorferi infection, including individuals who have received the licensed recombinant OspA Lyme disease vaccine (Lymerix). Positive or equivocal results should be supplemented by testing with a standardized Western Blot (second step) method. Positive Western Blot results provide evidence for exposure | {2} | Similarities | | | | --- | --- | --- | | Item | Device BioPlex 2200 Lyme Total | Predicate C6 B. burgdorferi (Lyme) ELISA Kit (K003754) | | | with B. burgdorferi. Diagnosis of Lyme borreliosis should be made based on the presence of B. burgdorferi antibodies, history, symptoms, and other laboratory data. Non-reactive first tier or negative second tier results should not be used to exclude borreliosis. | to or infection with B. burgdorferi. The diagnosis of Lyme disease must be made based on history, signs (such as erythema migrans), symptoms, and other laboratory data, in addition to the presence of antibodies to B. burgdorferi. Negative results (either first or second step) should not be used to exclude Lyme disease. | | Measured Analyte | Anti-Borrelia burgdorferi (IgM and IgG) antibodies | Same | | Assay Type | Qualitative | Same | | Differences | | | | --- | --- | --- | | Item | Device | Predicate | | Assay Technology | Automated multiplexed flow immunoassay | ELISA (enzyme- linked immunosorbent assay) | | Antigen | Recombinant p58, OspC type B (OspCB) and synthetic peptide FVlsE | Synthetic peptide (C6 peptide) | | Signal Detection | Fluorescence | Colorimetric | | Solid Phase | Antigen-coated paramagnetic microbeads | Antigen-coated microwell | | Conjugate | Murine monoclonal anti- human IgG, murine monoclonal anti-human IgM and phycoerythrin conjugated murine monoclonal anti-human FXIII antibody | Horseradish peroxidase- conjugated (HRP) goat anti-human IgG/IgM conjugate | | Sample Size | 5μL | 10μL | | Sample Handling/Process | Automated | Manual | | Unit of Measure | Antibody Index (AI) | Lyme Index (LI) | | Sample Matrix | Serum and plasma | Serum | | Instrumentation | BioPlex 2200 System | None (Manual) | K. Standard/Guidance Document Referenced (if applicable): N/A {3} L. Test Principle: Immunofluorescence M. Performance Characteristics (if/when applicable): 1. Analytical performance: a. Precision/Reproducibility: Precision: Precision testing of the BioPlex 2200 Lyme Total kit was performed in accordance with the Clinical and Laboratory Standards Institute (CLSI) EP5-A3 guideline. The serum samples were tested in duplicate, two runs per day, over 20 days (2 replicates x 2 runs x 20 days = 80 replicates per panel member) using one lot of the BioPlex 2200 Lyme Total Reagent Pack, Calibrator Set and Control Set. The results are summarized in the table below. Table 2: Precision Study | | | | Within Run (Repeatability) | | Between Run | | Between Day | | Total | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Sample Description | N | Mean (AI) | SD | %CV | SD | %CV | SD | %CV | SD | %CV | | High Negative 1 | 80 | 0.7 | 0.032 | 4.5% | 0.000 | 0.0% | 0.015 | 2.1% | 0.035 | 4.9% | | High Negative 2 | 80 | 0.9 | 0.050 | 5.4% | 0.000 | 0.0% | 0.010 | 1.1% | 0.051 | 5.5% | | Cut-Off | 80 | 1.0 | 0.040 | 3.9% | 0.000 | 0.0% | 0.030 | 2.8% | 0.050 | 4.8% | | Low Positive | 80 | 1.5 | 0.040 | 2.7% | 0.032 | 2.1% | 0.031 | 2.1% | 0.060 | 4.0% | | Mid Positive | 80 | 2.8 | 0.081 | 2.9% | 0.071 | 2.5% | 0.039 | 1.4% | 0.114 | 4.1% | | High Positive | 80 | 4.7 | 0.288 | 6.1% | 0.000 | 0.0% | 0.139 | 3.0% | 0.320 | 6.8% | Reproducibility: To assess reproducibility of the BioPlex 2200 Lyme Total kit, a reproducibility panel was prepared at Bio-Rad Laboratories. The panel contained members with varying levels of antibodies to the analytes in the BioPlex 2200 Lyme Total kit, and a positive control (antibody reactive for all analytes). Reproducibility testing was performed at 3 clinical trial sites. One lot of BioPlex 2200 Lyme Total Reagent Packs, BioPlex 2200 Lyme Total Calibrator Sets and BioPlex 2200 Lyme Total Control Sets was used to evaluate reproducibility. Each of the panel members and a positive and negative control were tested in quadruplicate on 2 runs per day over 5 days at each of 3 sites (4 replicates x 2 runs x 5 days = 40 replicates per panel member per site = 120 total replicates for 3 sites). The data was analyzed for intra-assay and inter-assay reproducibility according to the CLSI guidance EP15-A3. Results are shown in the table below. {4} Table 3: Reproducibility Study | Lyme Total Panel Member | N | Mean (AI) | Repeatability | | Between Run | | Between Day | | Between Site | | Total | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | | Low Negative | 120 | 0.4 | 0.020 | 5.1% | 0.000 | 0.0% | 0.004 | 1.0% | 0.006 | 1.5% | 0.022 | 5.4% | | High Negative | 120 | 0.7 | 0.035 | 5.1% | 0.013 | 1.8% | 0.023 | 3.3% | 0.032 | 4.5% | 0.055 | 7.8% | | Low Positive | 120 | 1.1 | 0.040 | 3.6% | 0.016 | 1.5% | 0.027 | 2.4% | 0.075 | 6.7% | 0.091 | 8.1% | | Mid Positive | 120 | 1.8 | 0.049 | 2.7% | 0.000 | 0.0% | 0.024 | 1.3% | 0.111 | 6.2% | 0.124 | 7.0% | | High Positive | 120 | 4.7 | 0.108 | 2.3% | 0.116 | 2.5% | 0.121 | 2.6% | 0.131 | 2.8% | 0.239 | 5.1% | b. Linearity/assay reportable range: N/A c. Traceability, Stability, Expected values (controls, calibrators, or methods): N/A d. Detection limit: N/A e. Analytical specificity: Analytical specificity: BioPlex 2200 Lyme Total kit analytical specificity was evaluated against 836 apparently healthy individuals from endemic and non-endemic regions and excluded prescreened blood donors. Results are summarized in the following table. Table 4: Analytical Specificity Study | | N | BioPlex 2200 Lyme Total (Negative percent agreement with expected result) | Legally marketed Lyme IgM/IgG Immunoassay (Negative percent agreement with expected result) | | --- | --- | --- | --- | | Normal Non-Endemic | 416 | 96.4% | 95.4% | | Normal Endemic | 420 | 96.4% | 94.8% | Cross-Reactivity: A cross-reactivity study was performed to determine if samples from various disease states and other potentially cross-reacting agents interfere with test results when tested with the BioPlex 2200 Lyme Total kit. Samples known to be positive for each cross-reactant listed in the table below were evaluated with the BioPlex 2200 Lyme Total kit. All samples were pre-tested by a commercially available Lyme assay and only those that tested negative by the commercially available assay were further tested by the BioPlex 2200 Lyme Total kit. Percent negative agreement for each potential cross reactant is shown below. {5} Table 5: Cross-Reactivity Study | Potential Cross-Reactant | Non-Reactive BioPlex 2200 Lyme Total kit Results/ Negative Commercial Lyme IgM/IgG Immunoassay Results | | | --- | --- | --- | | | N | Negative Agreement | | Anti-nuclear antibody (ANA) | 13 | 100.0% | | Babesiosis | 10 | 100.0% | | Chronic Fatigue Syndrome | 14 | 100.0% | | Cytomegalovirus | 13 | 100.0% | | Epstein-Barr Virus | 49 | 91.8% | | Ehrlichiosis | 11 | 90.9% | | HAMA | 13 | 100.0% | | Helicobacter Pylori | 12 | 100.0% | | HIV | 13 | 100.0% | | Influenza virus | 15 | 93.3% | | Leptospirosis | 34 | 97.1% | | Multiple sclerosis | 14 | 100.0% | | Parvovirus B19 | 14 | 100.0% | | Periodontal | 35 | 97.1% | | Rheumatoid arthritis | 14 | 100.0% | | Rheumatoid Factor positive | 13 | 100.0% | | Rickettsial diseases | 16 | 100.0% | | Rubella | 14 | 100.0% | | Syphilis | 48 | 97.9% | | Systemic Lupus Erythematosus | 15 | 100.0% | | Toxoplasmosis | 29 | 100.0% | | Varicella Zoster Virus | 14 | 100.0% | Interfering Substances: An interfering substances study was conducted to evaluate the potential interference of specific endogenous and exogenous substances with the BioPlex 2200 Lyme Total kit according to CLSI EP07-A2 guideline. No interference was observed with any of the substances tested. The substances and the maximum levels tested are shown in the table below: {6} Table 6: Interfering Substances | Substance | Concentration | | --- | --- | | Hemoglobin | 1000 mg/dL | | Bilirubin (unconjugated) | 20 mg/dL | | Bilirubin (conjugated) | 30 mg/dL | | Triglycerides | 3300 mg/dL | | Total Protein | 12 g/dL | | Cholesterol | 500 mg/dL | | Ascorbic Acid | 6 mg/dL | | EDTA | 800 mg/dL | | Sodium Heparin | 8000 units/dL | | Lithium Heparin | 8000 units/dL | # f. Assay cut-off: A total of 1,372 normal sera were used to determine the percentile cut-off in increments of 1/1000th for each analyte. Based on a retrospective selection of around the 98th percentile, the relative fluorescence intensity (RFI) corresponding to the chosen cutoff was assigned a value of 1.0 antibody index (AI), and subsequently evaluated for performance against clinically diagnosed samples. The statistics show that the 98th percentile cut-off meets the minimum agreement specifications while maximizing the clinical specificity. The assay employs an equivocal zone that brackets the cut-off (0.9-1.0 AI), with samples $\geq 1.1$ AI reported as reactive and $\leq 0.8$ AI reported as non-reactive. # 2. Comparison studies: # a. Method comparison with predicate device: Prospective Study: Performance of the BioPlex 2200 Lyme Total kit was evaluated using prospectively collected serum samples from patients submitted for Lyme disease testing originating from various geographically distinct locations in the U. S. A total of 792 serum samples were evaluated at three (3) U. S. clinical testing sites. Equivoal (Eqv.) samples are added to positives for calculating agreement results since they will be tested by the second tier Western blot. Results are shown in the table below. {7} Table 7: Percent Agreement with Predicate Device - ${1}^{\text{st }}$ Tier | | Commercial Lyme IgM/IgG Immunoassay | | | | | | | --- | --- | --- | --- | --- | --- | --- | | | | Pos | Eqv. | Neg | % Agreement | 95% CI | | BioPlex 2200 Lyme Total | Reactive | 65 | 0 | 30 | PPA = 70.1% (68/97)* | 60.0 - 79.0% | | | Eqv. | 2 | 1 | 4 | | | | | Non-Reactive | 21 | 8 | 661 | NPA = 95.1% (661/695)* | 93.2 - 96.6% | | Total | | 88 | 9 | 695 | | | * PPA=positive percent agreement NPA= negative percent agreement Second Tier Testing: All reactive/positive and equivocal samples by the BioPlex 2200 Lyme Total kit and the commercially available predicate device were tested by FDA-cleared IgG and IgM Western blot assays. Shown below are the second tier Western blot results (combined IgG and IgM) for samples that were reactive/ positive and equivocal in the prospective sample study. Table 8: Percent Agreement with Predicate Device - ${2}^{\text{nd }}$ Tier PPA | | Tier 1 + or Eqv. | WB + | WB - | | --- | --- | --- | --- | | Commercial Lyme IgM/IgG Immunoassay | 97 | 47 | 50 | | BioPlex 2200 Lyme Total | 102 | 49 | 53 | | Commercial Lyme IgM/IgG Immunoassay + BioPlex 2200 Lyme Total | 68 | 46 | 22 | | 1stTier PPA (95% CI) | 70.1% (60.0-79.0%) | 68/97 | | --- | --- | --- | | 2ndTier PPA (95% CI) | 97.9% (88.7-99.9%) | 46/47 | # b. Matrix comparison: Matched serum and plasma (EDTA and heparin) samples drawn from the same donor were acquired through a vendor. Paired serum and plasma samples were prepared and values within the measurement range of the assay were analyzed. Samples were spiked with high titer Lyme samples to obtain concentrations that span the assay range. Samples were assayed in replicates of two with the second replicate run in reverse order. Mean plasma AI values were compared to matched mean serum AI values. Linear regression analysis was used to determine the presence of a matrix effect when compared to serum. The regression correlation parameters for slope, intercept and correlation coefficient (r) are shown below. {8} Table 9: Matrix Comparison Study | Matrix Comparison | N | Slope (95% CI) | Intercept (95% CI) | Correlation (r) | | --- | --- | --- | --- | --- | | K2-EDTA vs. Serum | 77 | 1.02 (0.95 to 1.08) | 0.17 (-0.09 to 0.44) | 0.960 | | K3-EDTA vs. Serum | 74 | 1.01 (0.93 to 1.08) | 0.14 (-0.14 to 0.42) | 0.951 | | Sodium Heparin vs. Serum | 77 | 0.97 (0.91 to 1.02) | 0.09 (-0.13 to 0.30) | 0.970 | | Lithium Heparin vs. Serum | 78 | 0.97 (0.92 to 1.01) | 0.05 (-0.12 to 0.22) | 0.981 | # 3. Clinical studies: # a. Clinical Sensitivity: Sensitivity Study: Sensitivity of the BioPlex 2200 Lyme Total kit was evaluated using 105 clinically characterized samples from an archived collection containing early, convalescent and late phases of Lyme disease. The table below shows the sensitivity of the BioPlex 2200 Lyme Total kit for each of the disease phases along with a commercial Lyme IgM/IgG immunoassay. Table 10: Sensitivity with Respect to Disease Stage | Clinical Stage | N | BioPlex 2200 Lyme Total | | | | Commercial Lyme IgM/IgG Immunoassay | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | | | Reactive | Eqv. | Non-Reactive | Sensitivity 95% CI | Pos (+) | Eqv. | Neg (-) | Sensitivity 95% CI | | Acute (< 3 months) | 72 | 50 | 0 | 22 | 69.4% (50/72) 57.5 - 79.8% | 42 | 0 | 30 | 58.3% (42/72) 46.1 - 69.9% | | Convalescent (< 12 months) | 26 | 16 | 0 | 10 | 61.5% (16/26) 40.6 - 79.8% | 17 | 1 | 8 | 69.2% (18/26) 48.2 - 85.7% | | Late (> 12 months) | 7 | 6 | 0 | 1 | 85.7% (6/7) 42.1 - 99.6% | 5 | 0 | 2 | 71.4% (5/7) 29.0 - 96.3% | | Total | 105 | 72 | 0 | 33 | 68.6% (72/105) 58.8 - 77.3% | 64 | 1 | 40 | 61.9% (65/105) 51.9 - 71.2% | Correlation with CDC Panel: A panel of 280 positive and negative specimens from the Centers for Disease Control and Prevention (CDC) was tested for the presence of Lyme antibodies using the BioPlex 2200 Lyme Total kit. The results are presented as a means to convey further information on the performance of the BioPlex 2200 Lyme Total kit with a masked, characterized serum panel. This does not imply an endorsement of the BioPlex 2200 Lyme Total {9} kit by the CDC. Results are summarized in Table 11 below. Table 11: Testing of CDC Lyme Reference Sera | Sample Category | N (280) | BioPlex 2200 Lyme Total | | | | | --- | --- | --- | --- | --- | --- | | | | Reactive | Equivocal | Non-Reactive | % Agreement with Clinical Diagnosis | | Acute | 39 | 33 | 0 | 6 | 84.6% | | Convalescent | 31 | 29 | 0 | 2 | 93.5% | | Late | 20 | 20 | 0 | 0 | 100% | | Look-alike Diseases | 90 | 1 | 2 | 87 | 96.7% | | Healthy Controls | 100 | 1 | 2 | 97 | 97.0% | The BioPlex 2200 Lyme Total kit was further evaluated using the CDC panel and a commercially available predicate device. The results are summarized in the Table 12 below: Table 12: Comparative Testing of CDC Reference Sera | Sample Category(N=280) | N | BioPlex 2200 Lyme Total | | | | Commercial Lyme IgM/IgG Immunoassay | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | | | R(+) | Eqv. | NR (-) | % Agreement | Pos (+) | Eqv. | Neg (-) | % Agreement | | | Early EM | Acute | 30 | 24 | 0 | 6 | 80.0% | 19 | 0 | 11 | 63.3% | | | Convalescent | 30 | 28 | 0 | 2 | 93.3% | 27 | 0 | 3 | 90.0% | | Cardiac Lyme | Acute | 3 | 3 | 0 | 0 | 100% | 3 | 0 | 0 | 100% | | Neurological Lyme | Acute | 6 | 6 | 0 | 0 | 100% | 6 | 0 | 0 | 100% | | | Convalescent | 1 | 1 | 0 | 0 | 100% | 1 | 0 | 0 | 100% | | Lyme Arthritis/ Neuro. | Late | 20 | 20 | 0 | 0 | 100% | 20 | 0 | 0 | 100% | | Fibromyalgia | Look-alike Diseases | 15 | 0 | 1 | 14 | 93.3% | 0 | 0 | 15 | 100% | | Rheumatoid arthritis | | 15 | 0 | 0 | 15 | 100% | 0 | 0 | 15 | 100% | | Multiple sclerosis | | 15 | 0 | 0 | 15 | 100% | 0 | 0 | 15 | 100% | | Mononucleosis | | 15 | 0 | 2 | 13 | 86.7% | 2 | 0 | 13 | 86.7% | | Syphilis | | 15 | 0 | 0 | 15 | 100% | 1 | 0 | 14 | 93.3% | {10} | Sample Category(N=280) | N | BioPlex 2200 Lyme Total | | | | Commercial Lyme IgM/IgG Immunoassay | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | | | R(+) | Eqv. | NR (-) | % Agreement | Pos (+) | Eqv. | Neg (-) | % Agreement | | | Periodontitis | | 15 | 0 | 0 | 15 | 100% | 0 | 0 | 15 | 100% | | Endemic Negative Controls | Healthy Normals | 50 | 0 | 2 | 48 | 96.0% | 0 | 0 | 50 | 100% | | Non-Endemic Negative Controls | | 50 | 1 | 0 | 49 | 98.0% | 1 | 0 | 49 | 98.0% | R=Reactive, NR=Nonreactive b. Clinical specificity: N/A c. Other clinical supportive data (when a. and b. are not applicable): N/A 4. Clinical cut-off: N/A 5. Expected values/Reference range: Expected Values: The BioPlex 2200 Lyme Total kit was used to test 836 serum samples from apparently healthy subjects from both endemic and non-endemic regions and 792 test ordered samples from endemic regions in the U. S. The asymptomatic endemic population included 158 males ranging in age from 16 to 89 yrs. and 262 females ranging in age from 11 to 85 yrs. The asymptomatic non-endemic population included 139 males ranging in age from 3 to 91 yrs. and 275 females ranging in age from 13 to 95 yrs. with 2 samples of unknown age and gender. The test ordered endemic population included samples with de-identified patient data. The test results are presented in the following table. {11} Table 13: Expected Values | Population | N | BioPlex 2200 Lyme Total Qualitative Results | | | | --- | --- | --- | --- | --- | | | | Reactive | Equivocal | Non-Reactive | | Asymptomatic Non-Endemic | 416 | 11 (2.6%) | 4 (1.0%) | 401 (96.4%) | | Asymptomatic Endemic | 420 | 11 (2.6%) | 4 (1.0%) | 405 (96.4%) | | Test Ordered Endemic | 792 | 95 (12.0%) | 7 (0.9%) | 690 (87.1%) | # N. Proposed Labeling: The labeling is sufficient and it satisfies the requirements of 21 CFR Parts 801 and 809, as applicable # O. Conclusion: The submitted information in this premarket notification is complete and supports a substantial equivalence decision.