The AxSYM® Cortisol assay is a Fluorescence Polarization Immunoassay (FPIA) for the quantitative measurement of Cortisol in human serum, plasma or urine on the AxSYM® System to aid in the diagnosis and treatment of adrenal disorders.

Device Description

The AxSYM Cortisol assay utilizes Fluorescence Polarization Immunoassay (FPIA) technology. The AxSYM Cortisol Reagents and sample are pipetted in the following sequence:

Sample and all AxSYM Cortisol Reagents required for one test are pipetted by the sampling probe into various positions of a Reaction Vessel (RV).
Sample, the Cortisol Antiserum (antibody), pretreatment solution and Solution 4 (Line Diluent) are pipetted into one well of the RV.
Additional pretreatment solution 4 (Line Diluent) are pipetted to the cuvette of the RV.
The RV is immediately transferred into the Processing Center. Further pipetting is done in the Processing Center by the Processing Probe.
In the processing center, an aliquot of the predilution mixture and Solution 4 (Line Diluent) are transferred to the cuvette of the RV and the blank intensity of the sample is measured. A second aliquot of the predilution mixture is transferred to the cuvette along with the Cortisol Fluorescein Tracer. Cortisol from the sample and the Cortisol Fluorescein Tracer compete for binding sites on the antibody molecule. The intensity of polarized fluorescent light is measured by the FPIA optical assembly.

AI/ML Overview

Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:

Acceptance Criteria and Device Performance

Acceptance Criteria	Reported Device Performance
Reproducibility (%CV)	The total precision %CV of the AxSYM® Cortisol assay was determined to be less than or equal to 15.0. (The document states this as the finding, implying it meets an internal criterion, though no specific numerical acceptance threshold for %CV is explicitly stated beyond "less than or equal to 15.0").
Correlation Coefficient (r) to Predicate Device	Serum and Plasma (Least Squares): 0.96 (for a slope of 0.87 and Y-axis intercept of -0.74) Urine (Least Squares): 0.79 (for a Y-axis intercept of -0.59) Serum and Plasma (Passing-Bablok): 0.96 (for a slope of 0.93 and Y-axis intercept of -2.39) Urine (Passing-Bablok): 0.98 (for a slope of 0.79 and Y-axis intercept of -0.48) (No explicit acceptance criteria for correlation coefficient are stated, but these are the reported results from the comparison study.)
Accuracy (Slope and Intercept) vs. Predicate Device	Serum and Plasma (Least Squares): Slope of 0.87, Y-axis intercept of -0.74 Urine (Least Squares): Y-axis intercept of -0.59 (slope not provided for urine in least squares) Serum and Plasma (Passing-Bablok): Slope of 0.93, Y-axis intercept of -2.39 Urine (Passing-Bablok): Slope of 0.79, Y-axis intercept of -0.48 (No explicit acceptance criteria for slope and intercept are stated, but these are the reported results from the comparison study.)
Expected Values (Normal Range)	Not explicitly an acceptance criterion in the same vein as performance metrics, but a study was conducted to establish these: Serum (AM and PM): 4.2 to 38.4 µg/dL (median 10.8 µg/dL) for AM; 1.7 to 16.6 µg/dL (median 6.7 µg/dL) for PM Urine (24 hour): 32 to 243 µg/24 hour (median 88 µg/24 hours) (The expectation is simply to establish these ranges for the device.)

Study Details:

Sample size used for the test set and the data provenance:
- Reproducibility (Precision) Study: Three buffer-based panel members (1, 2, and 3) were assayed, in replicates of two, at two separate times per day, for 20 days. This means each panel member had 80 measurements (2 replicates * 2 times/day * 20 days).
- Comparison Study:
  - 130 endogenous and cortisol-spiked serum and sodium heparin plasma specimens.
  - 150 endogenous and cortisol-spiked urine specimens.
- Expected Values Study:
  - 50 serum specimens (AM and PM collections).
  - 49 urine specimens (24-hour collection).
- Data Provenance: Not explicitly stated (e.g., country of origin). The studies appear to be prospective, as samples were "tested using the AxSYM Cortisol assay" and "collected from apparently healthy individuals" for the expected values study.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable as this is an in-vitro diagnostic (IVD) device measuring a biomarker, not interpreting imaging or clinical data that would require expert consensus. The "ground truth" for the comparison study is the result obtained from the predicate device (Beckman Access® Cortisol assay).
Adjudication method for the test set:
- Not applicable. The "ground truth" for the comparison study is the result from the predicate device.
If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- Not applicable. This is an IVD device, not an AI-based imaging or
  diagnostic device that involves human readers interpreting results.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, the performance characteristics (reproducibility and comparison studies) reflect the standalone performance of the AxSYM® Cortisol assay without human-in-the-loop performance. The "human-in-the-loop" for this type of device would involve laboratory technicians performing the test, but the performance metrics provided are for the assay itself.
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For the comparison study, the ground truth was the results obtained from the predicate device (Beckman Access® Cortisol assay).
- For the reproducibility study, the "ground truth" is inherent to statistical precision analysis from repeated measurements.
- For the expected values study, the "ground truth" was the cortisol levels measured by the device itself in apparently healthy individuals to establish reference ranges.
The sample size for the training set:
- Not explicitly stated. For an IVD device, there isn't typically a "training set" in the same sense as machine learning algorithms. The development of the assay reagents and parameters would involve extensive R&D, but specific "training set" sizes are not usually disclosed in 510(k) summaries as they are not a discrete dataset used to train an algorithm.
How the ground truth for the training set was established:
- Not applicable, as there's no explicitly defined "training set" with ground truth in the context of an IVD like there would be for an AI algorithm. The development process would rely on established biochemical principles and extensive internal testing/optimization.

Summary

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FEB 2 0 2004

510(k) SUMMARY

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.

The assigned 510(k) number is: __ ____________________________________________________________________________________________________________________________________________

Submitter Information

Address:	Fujirebio Diagnostics, Inc.201 Great Valley ParkwayMalvern, PA 19355
Contact person:	Kimberly Peterson, (610) 240-3828
Summary preparation date:	November 26, 2003
Name of Device
Trade/Proprietary Name:	AxSYM® Cortisol assay
Common/Usual Name:	Cortisol Assay
Classification Name:	Cortisol (hydrocortisone and hydroxycorticosterone) tessystem

Predicate Device

Beckman Access® Cortisol assay

Device Description

The AxSYM Cortisol assay utilizes Fluorescence Polarization Immunoassay (FPIA) The AxSYM Cortisol Reagents and sample are pipetted in the following technology. sequence:

· Sample and all AxSYM Cortisol Reagents required for one test are pipetted by the sampling probe into various positions of a Reaction Vessel (RV).
Sample, the Cortisol Antiserum (antibody), pretreatment solution and Solution 4 (Line . Diluent) are pipetted into one well of the RV.
· Additional pretreatment solution 4 (Line Diluent) are pipetted to the cuvette of the RV.

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· The RV is immediately transferred into the Processing Center. Further pipetting is done in the Processing Center by the Processing Probe.
In the processing center, an aliquot of the predilution mixture and Solution 4 (Line Diluent) are transferred to the cuvette of the RV and the blank intensity of the sample is measured. A second aliquot of the predilution mixture is transferred to the cuvette along with the Cortisol Fluorescein Tracer. Cortisol from the sample and the Cortisol Fluorescein Tracer compete for binding sites on the antibody molecule. The intensity of polarized fluorescent light is measured by the FPIA optical assembly.

Intended Use

Summary of Performance characteristics

Reproducibility:

Precision was determined as described in the National Committee for Clinical Laboratory Standards (NCCLS) Protocol EP5-A. Three buffer-based panel members (1, 2, and 3) were assayed, in replicates of two, at two separate times per day, for 20 days. Three reagent lots were tested using two instruments, with a single standard calibration per reagent pack. The total precision was determined by calculating the standard deviation (SD) and percent coefficient of variation (%CV) values for each sample.

The total precision %CV of the AxSYM® Cortisol assay was determined to be less than or equal to 15.0.

Comparison Study

A total of 130, endogenous and cortisol-spiked serum and sodium heparin plasma specimens and 150, endogenous and cortisol-spiked urine specimens were tested using the AxSYM Cortisol assay and a Competitor Cortisol assay. Least squares and Passing-Bablok linear regression analyses were performed on all specimens with concentration values within the dynamic range of both assays (0 - 60ug/dL for the both the AxSYM and the Competitor Cortisol assavs).

Least squares linear regression analysis comparing the AxSYM® Cortisol assay to the Beckman Access® Cortisol assay for serum and plasma yielded a correlation coefficient of 0.96, a slope of 0.87 and Y-axis intercept of - 0.74. Least squares linear regression analysis for urine vielded a correlation coefficient of 0.79 and Y-axis intercept of - 0.59.

Passing-Bablok linear regression analysis comparing the AxSYM Cortisol assay to the Beckman Access Cortisol assay for serum and plasma vielded a correlation coefficient of

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0.96, a slope of 0.93, and Y-axis intercept -2.39. Passing-Bablok linear regression analysis for urine yielded a correlation coefficient of 0.98, a slope of 0.79, and Y-axis intercept -0.48.

Expected Values:

A study was conducted to establish the normal range for a given population using the AxSYM® Cortisol assay. A total of 50 serum (AM and PM collections) and 49 urine (24 hour collection) specimens from apparently healthy individuals were evaluated using the AxSYM® Cortisol assay.

In the population tested, the 95% confidence limit for the normal range of AM and PM cortisol in the serum specimens was determined to be 4.2 to 38.4 µg/dL (median value 10.8 µg/dL) and 1.7 to 16.6 ug/dL (median value 6.7 ug/dL) respectively. It is recommended that each laboratory establish its own range.

The 95% confidence limit for the normal range of cortisol in urine specimens was determined to be 32 to 243 µg/24 hour (median value 88 µg/24 hours). It is recommended that each laboratory establish its own range.

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Image /page/3/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 a stylized image of an eagle or bird-like figure with three wing-like shapes.

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

FEB 2 0 2004

Ms. Kimberly M. Peterson Manager, Regulatory Affairs Fuiirebio Diagnostics, Inc. 201 Great Valley Parkway Malvern, PA 19355

K033731 Re:

Trade/Device Name: AxSYM® Cortisol assay Regulation Number: 21 CFR 862.1205 Regulation Name: Cortisol (hydrocortisone and hydroxycorticosterone) test system Regulatory Class: Class II Product Code: JFT; JIT; JJX Dated: November 26, 2003 Received: December 15, 2003

Dear Ms. Peterson:

We have reviewed your Section 510(k) premarket notification of intent to market the device we nave roviewed your we determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to conniered pror to ritle) 2011-11-11, accordance with the provisions of the Federal Food, Drug, de nees that have been require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The I ou may , are expressions 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 (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can may or babyer to back of Federal Regulations (CFR), Parts 800 to 895. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean r lease be devilsed that i bromination that your device complies with other requirements of the Act that I Dr. I has matures and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).

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Page 2

This letter will allow you to begin marketing your device as described in your Section 510(k) I his lotter will and in yourse 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 information about the application of labeling requirements to your device, If you desire specific and advertising of your device, please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 594-3084. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Tour may of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely yours,

Jean M. Cooper, MS, DVM.

Yean M. Cooper, MS, D.V.M. Director Division of Chemistry and Toxicology Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE STATEMENT

510(k) Number (if known): K033731

Page 1 of 1

Device Name: AxSYM® Cortisol assay

prescription

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

Concurence of CDRH, Office of Device Evaulation (ODE)

(Optional Format 3-10-98)

Carol Benson
Division Sign Off

Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

510(k)K033731

102

Regulation Number and Section

§ 862.1205 Cortisol (hydrocortisone and hydroxycorticosterone) test system.

(a)
Identification. A cortisol (hydrocortisone and hydroxycorticosterone) test system is a device intended to measure the cortisol hormones secreted by the adrenal gland in plasma and urine. Measurements of cortisol are used in the diagnosis and treatment of disorders of the adrenal gland.(b)
Classification. Class II.