← Product Code [DFC](/submissions/IM/subpart-f%E2%80%94immunological-test-systems/DFC) · K082488 # DIAZYME LP(A) ASSAY (K082488) _General Atomics · DFC · Jan 13, 2009 · Immunology · SESE_ **Canonical URL:** https://fda.innolitics.com/submissions/CH/subpart-f%E2%80%94immunological-test-systems/DFC/K082488 ## Device Facts - **Applicant:** General Atomics - **Product Code:** [DFC](/submissions/IM/subpart-f%E2%80%94immunological-test-systems/DFC.md) - **Decision Date:** Jan 13, 2009 - **Decision:** SESE - **Submission Type:** Traditional - **Regulation:** 21 CFR 866.5600 - **Device Class:** Class 2 - **Review Panel:** Immunology ## Indications for Use The Diazyme Lp(a) is intended as a latex enhanced Immunoturbidimetirc assay for the in vitro quantitative determination of lipoprotein(a) [Lp(a)] concentration in human serum or plasma (EDTA) on Clinical Chemistry Systems. The measurement of Lp(a) is useful in evaluation lipid metabolism disorders and assessing atherosclerotic cardiovascular diseases in specific population, when used in conjunction with clinical evaluation. Diazyme Lp(a) Control is intended for use in monitoring the quality control of results obtained with the Diazyme Lp(a) reagents by turbidimetry. Diazyme Lp(a) calibrator is intended for use in establishing the calibration curve for the Diazyme Lp(a) reagents by turbidimetry. ## Device Story The Diazyme Lp(a) Assay is a latex-enhanced immunoturbidimetric in vitro diagnostic test. It utilizes latex particles coated with specific anti-Lp(a) antibodies. When mixed with human serum or plasma samples, Lp(a) in the sample binds to the antibodies, causing agglutination. This agglutination increases the turbidity of the sample, which is measured optically by an automated clinical chemistry analyzer. The degree of turbidity is directly proportional to the Lp(a) concentration in the sample. The assay is intended for use by laboratory professionals in clinical settings. Results are used by clinicians to evaluate lipid metabolism and assess cardiovascular disease risk, particularly in patients with premature atherosclerosis or specific surgical histories. The device provides quantitative data that aids in clinical decision-making regarding patient cardiovascular risk management. ## Clinical Evidence Bench testing only. Precision evaluated per CLSI EP5-A guidelines using three serum levels (17.2, 43.2, 70.0 mg/dL) over 20 days; total precision CV% ranged from 2.4% to 3.6%. Accuracy assessed via correlation studies with 76 serum samples against a commercial predicate, yielding a correlation coefficient of 0.9983. Interference studies showed <10% interference for triglycerides (1000 mg/dL), ascorbic acid (10 mmol/L), bilirubin (40 mg/dL), and hemoglobin (1000 mg/dL). ## Technological Characteristics Latex-enhanced immunoturbidimetric assay. Reagents: Glycine buffer, latex particles coated with anti-Lp(a) antibodies. Form factor: Liquid reagent, lyophilized calibrators/controls. Energy source: Optical measurement (turbidimetry) on automated chemistry analyzers. Connectivity: Standalone assay for clinical chemistry systems. Standards: CLSI EP05-A2, EP06-A, EP17-A. ## Regulatory Identification A low-density lipoprotein immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the low-density lipoprotein in serum and other body fluids. Measurement of low-density lipoprotein in serum may aid in the diagnosis of disorders of lipid (fat) metabolism and help to identify young persons at risk from cardiovascular diseases. ## Predicate Devices - Lp(a)-LATEX SEIKEN ASSAY KIT ([K013359](/device/K013359.md)) ## Submission Summary (Full Text) > This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com. > > Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/). {0} 1 of 8 # 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE A. 510(k) Number: k082488 B. Purpose for Submission: New 510(k) C. Measurand: Lipoprotein (a) [Lp(a)] D. Type of Test: Immunoturbidimetric E. Applicant: General Atomics F. Proprietary and Established Names: Diazyme Lp(a) Assay G. Regulatory Information: 1. Regulation section: 21CFR Sec.-866.5600-Low-Density Lipoprotein Immunological Test System. 21CFR Sec.-862.1150 Calibrator. 21CFR Sec -862.1660 Quality control material (assayed and unassayed). 2. Classification: Class 2, 2 and 1 (reserved) 3. Product code: DFC - Lipoprotein, Low-Density, Antigen, Antiserum, Control JIT- calibrator, secondary JJX - single (specified) analyte controls (assayed and unassayed) 4. Panel: Chemistry (75) H. Intended Use: 1. Intended use(s): See indication(s) for use below 2. Indication(s) for use: The Diazyme Lp(a) is intended as a latex enhanced Immunoturbidimetirc assay for the in vitro quantitative determination of lipoprotein(a) [Lp(a)] concentration {1} in human serum or plasma (EDTA) on Clinical Chemistry Systems. The measurement of Lp(a) is useful in evaluation lipid metabolism disorders and assessing atherosclerotic cardiovascular diseases in specific population, when used in conjunction with clinical evaluation. Diazyme Lp(a) Control is intended for use in monitoring the quality control of results obtained with the Diazyme Lp(a) reagents by turbidimetry Diazyme Lp(a) calibrator is intended for use in establishing the calibration curve for the Diazyme Lp(a) reagents by turbidimetry. 3. Special conditions for use statement(s): Prescription use Lp(a) values should be interpreted in conjunction with clinical evaluation and other lipoprotein tests when assessing atherosclerotic cardiovascular disease in specific populations. The effects of the impact of Apo A size heterogeneity on lipoprotein (a) measurements by this method have not been assessed. 4. Special instrument requirements: Performance data was provided for use with the Hitachi 717 I. Device Description: Lipoprotein (a) Reagent Composition Reagent 1 Glycine Buffer Solution Reagent 2 Latex particles coated with anti-Lp(a) antibodies Reagent Preparation 1. The Lp(a) assay reagent provided is ready to use. 2. Physiological saline is needed to dilute high Lp(a) samples. Lipoprotein (a) Calibrator Set 5 vials containing lyophilized calibrators with different Lp(a) concentrations (≈ 6.5, 14.2, 31.4, 62.4, 83.8 mg/dL). 5 x 1.0 mL (after reconstitution) Each serum donor unit used in the preparation of this product has been tested using FDA approved methods and found to be non-reactive for HBsAg, HIV and HCV. Lipoprotein (a) Control Set 2 vials containing lyophilized calibrators with different Lp(a) concentrations (target range ≈ 17.3 - 23.5, 50.1 - 67.6 mg/dL). 2 x 1.0 mL (after reconstitution) Each serum donor unit used in the preparation of this product has been tested using 2 of 8 {2} FDA approved methods and found to be non-reactive for HBsAg, HIV and HCV. ## J. Substantial Equivalence Information: 1. Predicate device name(s): Denka Lp(a) assay Dade Behring, N LP(a) Standard Kamiya Biomedical, K-Assay LP(a) Controls 2. Predicate 510(k) number(s): k013359 k013126 k023853 3. Comparison with predicate: Intended use | Diazyme Lp(a) Assay | Denka Lp(a) Assay | Equivalency | | --- | --- | --- | | The Diazyme Lp(a) immunoassay is intended for the in vitro quantitative determination of Lipoprotein (a) in human serum and plasma. | The Lp(a) Assay is a latex in vitro diagnostic immunoassay for the quantitative determination of Lipoprotein (a) in human serum and plasma. | Same | Principle | Diazyme Lp(a) Assay | Denka Lp(a) Assay | Equivalency | | --- | --- | --- | | The Diazyme Lipoprotein (a) Assay is based on a latex enhanced immunoturbidimetric assay. Lp(a) in the sample binds to specific anti-Lp(a) antibody, which is coated on latex particles, and causes agglutination. The degree of the turbidity caused by agglutination can be measured optically and is proportional to the amount of Lp(a) in the sample. | The Lp(a)-Latex Seiken Assay kit is a latex-enhanced immunoturbidimetric in vitro diagnostic assay. Lp(a) in the sample binds to the specific anti-Lp(a) antibody, which is adsorbed to latex particles and agglutinates. The agglutination is detected as an absorbance change when read on an automated chemistry analyzer (at 700 nm). The magnitude of the change is proportional to the quantity of Lp(a) in the sample. The actual concentration is then determined by interpolation from a calibration curve prepared from calibrators of know concentrations. | Same | {3} 4 of 8 Product Type | Diazyme Lp(a) Assay | Denka Lp(a) Assay | Equivalency | | --- | --- | --- | | Calibrator, Reagent, Instrument | Calibrator, Reagent, Instrument | Same | Calibrator Comparison | Diazyme Lp(a) Assay | Denka Lp(a) Assay | Equivalency | | --- | --- | --- | | Lyophilized form | Lyophilized form | Same | Control Comparison | Diazyme Lp(a) Assay | Denka Lp(a) Assay | Equivalency | | --- | --- | --- | | Lyophilized form | Lyophilized form | Same | K. Standard/Guidance Document Referenced (if applicable): CLSI - Evaluation of Precision Performance of Clinical Chemistry Devices - EP05-A2 CLSI - Evaluation of the Linearity of Quantitative Analytical Methods - EP06-A CLSI - Protocols for Determination of Limits of Detection and Limits of Quantitation - EP17-A L. Test Principle: The Diazyme Lipoprotein (a) Assay is based on a latex enhanced immunoturbidimetric assay. Lp(a) in the sample binds to specific anti-Lp(a) antibody, which is coated on latex particles, and causes agglutination. The degree of the turbidity caused by agglutination can be measured optically and is proportional to the amount of Lp(a) in the sample. M. Performance Characteristics (if/when applicable): 1. Analytical performance: a. Precision/Reproducibility: The precision of the Diazyme Lp(a) Enzymatic Assay was evaluated according to Clinical and Laboratory Standards Institute EP5-A guideline. In the study, three levels of serum specimens containing about 17.2, 43.2, and 70.0 mg/dL Lp(a) respectively are tested with 2 runs per day with duplicates over 20 working days on Hitachi 717. | Within Run Precision (Sr) | | | | | --- | --- | --- | --- | | | Level 1: mg/dL Lp(a) | Level 2: mg/dL Lp(a) | Level 3: mg/dL Lp(a) | | Number | 80 | 80 | 80 | | Mean (mg/dL) | 18.3 | 42.2 | 71.66 | | SD (mg/dL) | 0.47 | 0.59 | 0.76 | | CV% | 2.6 | 1.4 | 1.1 | | | | | | {4} | Within Run Precision (Sr) | | | | | --- | --- | --- | --- | | | Level 1: mg/dL Lp(a) | Level 2: mg/dL Lp(a) | Level 3: mg/dL Lp(a) | | Number | 80 | 80 | 80 | | Mean (mg/dL) | 18.3 | 42.2 | 71.66 | | SD (mg/dL) | 0.66 | 1.38 | 1.71 | | CV% | 3.6 | 3.3 | 2.4 | b. Linearity/assay reportable range: Eleven levels of linearity set were prepared by diluting a serum control containing $100\mathrm{mg / dL}$ LP(a) with saline according to Clinical and Laboratory Standards Institute EP6-A to test a range from 5 to $100\mathrm{mg / dL}$ LP(a) and was shown to be linear. The following regression equation was obtained. $$ \begin{array}{l} y = 0. 9 9 4 5 x + 0. 5 9 9 7 \\ R ^ {2} = 0. 9 9 8 5 \\ \end{array} $$ The assay has a linear range up to $100\mathrm{mg / dL}$ and a low reportable range to $5.44\mathrm{mg / dL}$ based on LOQ. c. Traceability, Stability, Expected values (controls, calibrators, or methods): Calibrators Using a single lot of predicate device reagents and calibrator, Diazyme Lp(a) master lot of calibrator materials were assigned values as follows. The calibrator materials were assayed as samples three times in triplicate on the Hitachi 717 Analyzer. For each calibrator level, mean values were calculated from the data points and assigned as the calibrator value. For each new lot of calibrator materials produced, the master lot or reference lot calibrator is used in conjunction with the reference lot of Diazyme reagents to test and verify calibrator value. Controls Using in-house reagents and calibrator, control materials were assigned values as follows. The control materials were assayed as samples three times in triplicate on the Hitachi 7171 analyzer with a single lot of released reagents and calibrator. For each control level, mean values were calculated from the data points and assigned as the target value. Stability for both calibrators and controls is based on real time stability studies. d. Detection limit: The LOB, LOD, and LOQ of Diazyme LP(a) Assay was determined according to CLSI EP17-A: Protocols for Determination of Limits of {5} Detection and Limits of Quantitation; Approved Guideline on the Hitachi 717. LOB was determined using a BSA solution in phosphate buffered saline and tested twenty times each day for three days. The LOD was determined using low samples tested in replicates of four each day for three days. LOQ was determined using 6 samples ranging from 0.42 to 17.38 mg/dL and using a fitted curve to determine the value at 20% CV. The results obtained are as follows: - The Limit of Blank (LOB) for Lp(a) assay is 0.64 mg/dL - The Limit of detection (LOD) for Lp(a) assay is 1.14 mg/dL - The Limit of Quantitation (LOQ) for Lp(a) assay is 5.44 mg/dL e. Analytical specificity: Two levels of Lp(a) 16 and 43 mg/dL were tested for interference from hemoglobin to 1000 mg/dL, Bilirubin to 40 mg/dL, conjugated Bilirubin to 40 mg/dL, triglyceride to 1000 mg/dL and Ascorbic Acid to 10 mM with no interference based on ± 10% deviation from expected result. f. Assay cut-off: Not Applicable 2. Comparison studies: a. Method comparison with predicate device: To demonstrate method comparison, the Diazyme LP(a) Assay was tested with individual serum samples and with the Denka Lp(a)-Latex Seiken Assay and calibrator (k013359). A total of 76 serum samples were used for the comparison experiment. To ensure the concentrations of LP(a) distributed across the reportable dynamic range, some serum samples were spiked with stock solution of LP(a) or diluted with saline to targeted concentrations. LP(a) concentrations obtained with Diazyme LP(a) Enzymatic Assay are plotted against that obtained with Denka Seiken Lp(a) Reagent kit (Predicate) on HITACHI 717. 6 of 8 {6} ![img-0.jpeg](img-0.jpeg) Conclusion: For the 76 serum samples with Lp(a) ranging from 5.21 mg/dL to 94.83 mg/dL, the correlation coefficient between the two methods was 0.9983, slope was 0.9895, and y intercept was 0.0279. b. Matrix comparison: Lp(a) levels of 20 sample pairs covering the assay range using EDTA plasma to serum yielded the following data analysis: $\mathrm{y} = 1.044\mathrm{x} + 0.0407\mathrm{R}^2 = 0.9803$ 3. Clinical studies: a. Clinical Sensitivity: Not Applicable b. Clinical specificity: Not Applicable c. Other clinical supportive data (when a. and b. are not applicable): Not Applicable 4. Clinical cut-off: Not Applicable 5. Expected values/Reference range: In the labeling the sponsor has cited published literature as follows: "Studies have shown the expected range for Lp(a) has been reported to be between 10 and 30 mg/dL. Some studies have indicated that Lp(a) concentrations in African Americans may differ from Caucasians with African American ranges higher." {7} 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. 8 of 8 --- **Source:** [https://fda.innolitics.com/submissions/CH/subpart-f%E2%80%94immunological-test-systems/DFC/K082488](https://fda.innolitics.com/submissions/CH/subpart-f%E2%80%94immunological-test-systems/DFC/K082488) **Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact). **Cite:** Innolitics at https://innolitics.com