K982271 · Wako Chemicals USA, Inc. · MRR · Sep 22, 1998 · Clinical Chemistry
Device Facts
Record ID
K982271
Device Name
WAKO DIRECT LDL-C
Applicant
Wako Chemicals USA, Inc.
Product Code
MRR · Clinical Chemistry
Decision Date
Sep 22, 1998
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 862.1475
Device Class
Class 1
Indications for Use
The Wako Direct LDL-C test is an in vitro diagnostic assay for the quantitative determination of low density lipoprotein cholesterol in serum.
Device Story
Wako Direct LDL-C is an in vitro diagnostic assay for quantitative serum LDL-cholesterol measurement; intended for use in clinical laboratories on automated analyzers. Principle: homogeneous enzymatic assay. Sample mixed with Reagent 1 (R1) containing protecting reagent to shield LDL from enzymes; cholesterol esterase (CHE) and cholesterol oxidase (CO) react with non-LDL lipoproteins (CM, VLDL, HDL); hydrogen peroxide produced is decomposed by catalase in R1. Reagent 2 (R2) added to remove protecting reagent and inactivate catalase with sodium azide; CHE and CO then react specifically with LDL-C. Resulting hydrogen peroxide reacts with HDAOS and 4AA in presence of peroxidase to form blue color complex. Absorbance measured at ~600nm to calculate LDL concentration. Eliminates labor-intensive ultracentrifugation or calculation-based estimates (Friedwald formula). Provides clinicians with direct LDL-C values to assess coronary heart disease (CHD) risk and manage lipid metabolism disorders.
Clinical Evidence
Bench testing only. Comparison studies against predicate assay yielded correlation coefficients of 0.986 (serum) and 0.988 (plasma). Comparison against reference beta-quantification method yielded correlation coefficient of 0.983. Minimum detectable level is 1 mg/dL. Precision studies indicate acceptable day-to-day performance.
Technological Characteristics
Homogeneous enzymatic assay. Reagents: R1 (protecting reagent, catalase), R2 (sodium azide). Chromogenic system: HDAOS, 4-aminoantipyrine, peroxidase. Detection: Spectrophotometric absorbance at ~600nm. Automated analyzer compatible. No specific materials of construction or connectivity standards listed.
Indications for Use
Indicated for the measurement of LDL-cholesterol in serum. Used in the diagnosis and treatment of disorders involving excess cholesterol in the blood and lipoprotein metabolism disorders.
Regulatory Classification
Identification
A lipoprotein test system is a device intended to measure lipoprotein in serum and plasma. Lipoprotein measurements are used in the diagnosis and treatment of lipid disorders (such as diabetes mellitus), atherosclerosis, and various liver and renal diseases.
Predicate Devices
Equal LDL Direct Liquid Select Cholesterol reagent
Submission Summary (Full Text)
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SEP 2 2 1998
Wak
Wako Chemicals USA, Inc. 1600 Bellwood Road, Richmond, VA 23237 U.S.A.
## 510(k) Summary of Safety and Effectiveness
The Wako Direct LDL-C test is an in vitro diagnostic assay for the quantitative determination of low density lipoprotein cholesterol in serum.
## Summary:
Blood total cholesterol levels have long been known to be related to coronary heart disease (CHD). In recent years, in addition to total cholesterol, LDL-C has become an important tool used to assess an individual risk of developing CHD since a strong positive relationship between LDL-C concentration and the incidence of CHD was reported. Thus, there has been substantial interest in LDL-C measurements, and most clinical laboratories routinely perform LDL-C analysis.
The currently accepted reference method is generally referred to as "beta quantification"24. which involves ultracentrifugation. Because this method is labor intensive and technique dependent, it is generally not used for routine testing. The Friedwald formula is most commonly used for routine purposes. However, since formula estimates LDL-C from measurements of total cholesterol, triglyceride and high density lipoprotein cholesterol (HDL-C), the LDL-C calculation depends on the accuracy and precision of the three measurements. The Wako L-type LDL-C test is a homogeneous assay, which eliminates the preparatory steps or calculation, and thus, can be applied to automated analyzers.
## Principle:
When the sample is mixed with R1, the protecting reagent binds to LDL and protects LDL from enzyme reactions. Cholesterol esterase (CHE) and cholesterol oxidase (CO) react with non-LDL lipoproteins (chylomicron (CM), very low density lipoprotein (VLDL) and HDL). Hydrogen peroxide produced by the enzyme reactions with non-LDL cholesterol is decomposed by a catalase in Reagent 1. When Reagent 2 is added, the protecting reagent is removed from LDL and catalase in inactivated by sodium azide (NaN3). In this second process, CHE and CO react only with LDL-C. Hydrogen peroxide produced by the enzyme reactions with LDL-C yields a color complex upon oxidase condensation with N-(2-hydroxy-3-sufopropyl)-3,5-dimethoxyaniline {HDAOS} and 4aminoantipyrine (4AA) in the presence of peroxidase (POD). By measuring the absorbance of the blue color complex produced, at approximately 600nm, the LDL concentration in the sample can be calculated.
The safety and effectiveness of the Wako Direct LDL assay is demonstrated by its substantial equivalency to the Equal LDL Direct Liquid Select Cholesterol reagent. Both test systems are used to measure low density lipoprotein cholesterol in serum. In comparison studies against the predicate assay, a correlation coefficient of 0.986 and a regression equation of y =1.018x + 0.135 and a correlation coefficient of 0.988 and a regression equation of 0.98x + 4.18 were obtained for serum and plasma samples, respectively. In comparison studies against the reference method, a correlation coefficient of 0.983 and a regression equation of y = 0.97x + 5.12 was obtained for serum
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K982271
samples. Precision studies indicate acceptable values can be obtained on a day to day basis. The minimum detectable level of this method is 1 mg/dL.
## References
- Burtis, C.A. and Ashwood, E.R., Tietz Textbook of Clinical Chemistry. 2nd Ed., 1. Saunders, Philadelphia, 1994.
- Rifai, N., Warnick, G.R. and Dominiczak, M.H., Ed. Handbook of Lipoprotein 2. Testing. AACC Press, Washington, DC, USA, 1997.
- Friedwald, W.T., Levy, R.I. and Fredrickson, D.S. Estimation of the concentration 3. of low density lipoprotein cholesterol in plasma without use of the centrifuge. Clin. Chem. 18, 449-502 (1972).
Tung Mallory
September 14, 1998 Wako Diagnostics Wako Chemicals USA, Inc. 1600 Bellwood Road Richmond, VA 23237
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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" around the perimeter. Inside the circle is an abstract symbol resembling an eagle or bird in flight, composed of three curved lines.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
SEP 2 2 1998
Tonya Mallory · Senior Manager Wako Chemicals USA, Inc. 1600 Bellwood Road Richmond, Virginia 23237
Re : K982271 Wako Direct LDL-C Regulatory Class: I Product Code: MRR Dated: June 8, 1998 Received: June 29, 1998
Dear Ms. Mallory:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions The general controls provisions of the Act of the Act. include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Requlations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531… through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Page 2
Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770) 488-7655.
This letter will allow you to begin marketing your device as described in your 510 (k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".
Sincerely yours,
Steven Litman
Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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Page_ of
1982291 510(k) Number (if known):_ Wako Divilet LDL-C Device Name:
Indications For Use:
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(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use (Per 21 CFR 801.
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OR
Over-The-Counter Use
(Optional Format 1-2-9
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