The intended use for the N-ASSAY L AST/GOT Reagent is for the quantitative determination of serum aspartate aminotransferase (AST) activity in human serum in the diagnosis and treatment of certain types of liver, heart, and muscle diseases. For in vitro diagnostic use only.

Device Description

The N-ASSAY L AST/GOT reagent is based on an the optimized enzymatic AST kinetic method as recommended by the Japan Society of Clinical Chemistry, shows good correlation with similar AST reagents, practically no interference by coexistent substances, high sensitivity with good reproducibility, wide assay range, and is convenient ready-to-use liquid type reagent.

In this procedure, L-Aspartic Acid and a-Ketoglutaric Acid are translated by aspartate aminotransferase (AST) to produce Oxalacetic Acid and Glutamic Acid. Oxalacetic Acid is reduced by Malic Dehydrogenase to produce Malic Acid with the concurrent oxidation of nicotinamide adenine dinucleotide reduced (NADH) to nicotinamide adenine dinucleotide (NAD). The NADH absorbs light at 340 nm (main) and 405 nm (sub) and can be detected spectrophotometrically. The decrease per minute in absorbance measured at 340 nm (main) and 405 (sub), due to the decrease of NADH, is directly proportional to the AST activity in the sample.

AI/ML Overview

The Crestat N-ASSAY L AST/GOT Reagent is an in vitro diagnostic device used for the quantitative determination of serum aspartate aminotransferase (AST) activity in human serum, aiding in the diagnosis and treatment of certain liver, heart, and muscle diseases.

1. A table of acceptance criteria and the reported device performance:

Performance Metric	Acceptance Criteria (Implied)	Reported Device Performance
Correlation Coefficient	High correlation with predicate device (e.g., >0.95)	Without P5P: 0.99178 (versus Boehringer Mannheim AST liquid reagent)
		With P5P: 0.97146 (versus Boehringer Mannheim AST liquid reagent)
Regression Equation	Slope close to 1, intercept close to 0 (indicating good agreement)	Without P5P: y = 0.9754x - 0.5665
		With P5P: y = 0.5807x + 1.5184
Precision	Acceptable day-to-day variability	Acceptable values obtained on a day-to-day basis
Minimum Detectable Level	Low detection limit for clinical utility	1 IU/L
Linearity	Wide assay range for clinical utility	Linear to 2,000 IU/L

2. Sample size used for the test set and the data provenance:

Sample Size: The document does not explicitly state the number of samples used in the comparison studies. It refers to "serum samples" in plural, implying more than one but providing no specific quantity.
Data Provenance: Not explicitly stated. However, given that it's an in vitro diagnostic device for human serum, it's highly probable the samples were from human patients. The country of origin and whether the data was retrospective or prospective is not mentioned.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

The concept of "ground truth" in the context of expert consensus isn't directly applicable here in the same way it would be for image analysis or disease diagnosis. For this device, the "ground truth" for the test set is established by the performance of the predicate device (Boehringer Mannheim Corporation AST liquid reagent). The predicate device itself would have undergone its own validation based on established clinical chemistry methods.
Therefore, there were no experts explicitly used to establish ground truth for this device's test set in the manner of adjudication. The predicate device's results are considered the reference.

4. Adjudication method for the test set:

None. Adjudication is typically used when human interpretation of data is involved to establish a consensus ground truth. In this case, the test involved comparing the quantitative results of the new device against a predicate device, which is an objective measurement comparison.

5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done:

No. An MRMC study is not relevant for this type of quantitative diagnostic assay. MRMC studies are primarily for evaluating the diagnostic performance of human readers, often with and without AI assistance, especially in image-based diagnostics. This study focuses on the analytical performance of a chemical reagent.

6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:

Yes, this was a standalone study. The N-ASSAY L AST/GOT Reagent is a chemical assay, and its performance was evaluated intrinsically by comparing its quantitative results to a predicate device. There is no "human-in-the-loop" component in the direct measurement process being evaluated here, beyond standard laboratory handling and operation.

7. The type of ground truth used:

The "ground truth" in this context is the results obtained from the predicate device (Boehringer Mannheim Corporation AST liquid reagent). This predicate device itself is considered a well-established and validated method for measuring AST activity.

8. The sample size for the training set:

The concept of a "training set" in the machine learning sense is not applicable to this chemical reagent. There is no algorithm that is "trained" on data. The reagent's performance is based on its chemical properties and optimized enzymatic method. Therefore, no training set was used.

9. How the ground truth for the training set was established:

As there is no training set for this chemical assay, the question of how its ground truth was established is not applicable.

Summary

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CRESTAT DIAGNOSTICS, INC

MAR 26 1998 25549 Adams Avenue Murrieta, CA 92562

510(K) SUMMARY OF SAFETY AND EFFECTIVENESS

This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR § 807.92.

K980902 The assigned 510(k) number is:

Date: March 2, 1998

Submitted by: Colin Getty KAMIYA BIOMEDICAL COMPANY 910 Industry Drive, Seattle WA 98188 TEL: 206-575-8068; FAX: 206-575-8094

For:

Crestat Diagnostics, Inc. 25549 Adams Avenue Murrieta, CA 92562

N-ASSAY L AST/GOT (AST Assay Reagent) Product:

Aspartate aminotransferase (AST/GOT) is widely distributed with high concentrations in the heart, liver, skeletal muscle, and kidney. Damage or disease to any of these tissues may result in raised serum or plasma levels of AST. Karmen et al. described the first kinetic assay of AST for diagnostic purposes in 1955. Since then, this method has been improved and forms the basis of many national and international recommended procedures.

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CRESTAT DIAGNOSTICS, INC.

510(K) SUMMARY OF SAFETY AND EFFECTIVENESS (Continued)

The safety and effectiveness of the liquid Crestat N-ASSAY L AST/GOT Reagent is demonstrated by its substantial equivalence to the Boehringer Mannheim Corporation AST liquid reagent (K861792) which is based on a similar enzymatic method as recommended by the IFCC. Both test systems are intended to quantitatively measure AST activity in human serum.

In comparison studies against the predicate assay (without the optional pyridoxal-5phosphate or P5P activation), a correlation coefficient of 0.99178 and a regression equation y = 0.9754 x + -0.5665 was obtained with serum samples. In comparison studies against the predicate assay (with the optional P5P activation), a correlation coefficient of 0.97146 and a regression equation y = 0.5807 x + 1.5184 was obtained with serum samples. Precision studies indicate acceptable values can be obtained on a day to day basis. The minimum detectable level of this method is 1 IU/L. The N-ASSAY L AST/GOT reagent is linear to 2,000 IU/L.

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Image /page/2/Picture/2 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is a stylized image of an eagle with its wings spread, with three human figures in the negative space between the wings and body of the eagle.

MAR 26 1998 2098 Gaither Road

Food and Drug Administration Rockville MD 20850

Crestat Diagnostics, Inc. C/O Colin Getty KAMIYA Biomedical Company 910 Industry Drive Seattle, Washington, 98188

K980902 e : N-ASSAY L AST/GOT Requlatory Class: II Product Code: CIT March 2, 1998 Dated: Received: March 10, 1998

Dear Mr. Getty:

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, Druq, 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 reqistration, 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 requlations 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 Reqister. 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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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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INDICATIONS FOR USE STATEMENT

K980902 510(k) Number (if known):

N-ASSAY L AST/GOT (AST Assay Reagent) Device Name:

Indications For Use:

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of Laboratory vices
510(k) Number K980902

Prescription Use
(Per 21 CFR 801.109)

Over-The-Counter Use

Optional Format 1-2-96)

Regulation Number and Section

§ 862.1100 Aspartate amino transferase (AST/SGOT) test system.

(a)
Identification. An aspartate amino transferase (AST/SGOT) test system is a device intended to measure the activity of the enzyme aspartate amino transferase (AST) (also known as a serum glutamic oxaloacetic transferase or SGOT) in serum and plasma. Aspartate amino transferase measurements are used in the diagnosis and treatment of certain types of liver and heart disease.(b)
Classification. Class II (special controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.