The REAADS Protein S Antigen Test Kit is an in vitro diagnostic assay for the quantitative determination of Total and Free Protein S levels in human plasma (as a percentration) by enzyme-linked immunosorbent assay (ELISA). Plasma levels of Protein S may be used in conjunction with the results from other assays as an aid in diagnosing congenital or acquired Protein S deficiencies associated with thrombotic disease.

Device Description

The REAADS Protein S Antigen Test Kit is a sandwich enzyme linked immunosorbent assay (ELISA). A capture antibody specific for human Protein S is coated to 96-microwell polystyrene plate. Diluted patient plasma is incubated in the wells, allowing any available Protein S to bind to the anti-human Protein S antibody on the microwell surface. The plates are washed to remove any unbound plasma molecules. Bound Protein S is quantitated using an HRP conjugated anti-human Protein S detection antibody. Any unbound conjugated antihuman Protein S is washed away after an incubation period. A chromogenic substrate of tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) is added to develop a colored reaction. The intensity of the color is measured spectrophotometrically at 450nm in optical density (O.D.) units. Protein S relative percent concentrations in patient plasma are determined against a curve prepared from a reference plasma provided with the kit. Results obtained from diluted plasma samples not pretreated with polyethylene glycol (PEG) represent the Total Protein S concentration from that sample. To measure Free Protein S, PEG is added to plasma samples prior to beginning the assay to precipitate the Protein S-C4b binding protein complex. The supernatant fraction containing Free Protein S may be tested along with the untreated plasma sample. Both Total (untreated) and Free (PEG-treated) Protein S concentrations are determined following the same assay procedure described using separate reference curves.

AI/ML Overview

Table of Acceptance Criteria and Reported Device Performance:

Acceptance Criteria	Device Performance (Total Protein S)	Device Performance (Free Protein S)
Correlation (r)	0.924	0.934
P-value (ANOVA)	0.494	0.346

Sample Size Used for the Test Set and Data Provenance:
- Sample Size: Not specified in the provided text, only referred to as "clinical samples."
- Data Provenance: Not specified in the provided text. It is unclear if it's retrospective or prospective or the country of origin.
Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
- Not applicable. The study compares the new device to existing legally marketed predicate devices, not against expert-established ground truth for diagnosis/classification.
Adjudication Method for the Test Set:
- Not applicable. The study is a comparative performance study against predicate devices, not one requiring adjudication of diagnostic outcomes.
Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, a MRMC study was not done. The study compares the performance of the new device against predicate devices using quantitative measurements of Protein S levels.
Standalone Performance (Algorithm only without human-in-the-loop performance):
- Yes, this is a standalone performance study. The REAADS Protein S Antigen Test Kit is an in vitro diagnostic assay that produces quantitative results directly. Human intervention is involved in conducting the assay and interpreting the results in a clinical context, but the performance evaluation here specifically focuses on the accuracy of the assay itself in determining Protein S levels compared to existing methods.
Type of Ground Truth Used:
- The "ground truth" for this study is the results obtained from legally marketed predicate devices: the Helena Protein S Antigen Rocket EID Method and the Helena Free Protein S Reagent. The study aims to demonstrate substantial equivalence to these established methods.
Sample Size for the Training Set:
- Not applicable. This is not a machine learning model, so there is no "training set." The device is a laboratory assay.
How the Ground Truth for the Training Set Was Established:
- Not applicable, as there is no training set for this type of device.

Summary

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AUG 1 3 1997

SUMMARY OF 510(K) SAFETY AND EFFECTIVENESS

REAADS Protein S Antigen Test Kit

July 30, 1997

Page 1 of 2

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 REAADS Protein S Antigen Test Kit is compared to a legally marketed predicate device and a substantial equivalence claim is made. The predicate devices are the Helena Protein S Antigen Rocket EID Method, and the Helena Free Protein S Reagent, both currently manufactured and marketed by Helena Laboratories, Beaumont, Texas.

The REAADS Protein S Antigen Test Kit is a sandwich enzyme linked immunosorbent assay A capture antibody specific for human Protein S is coated to 96-microwell (ELISA). polystyrene plate. Diluted patient plasma is incubated in the wells, allowing any available Protein S to bind to the anti-human Protein S antibody on the microwell surface. The plates are washed to remove any unbound plasma molecules. Bound Protein S is quantitated using an HRP conjugated anti-human Protein S detection antibody. Any unbound conjugated antihuman Protein S is washed away after an incubation period. A chromogenic substrate of tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) is added to develop a colored reaction. The intensity of the color is measured spectrophotometrically at 450nm in optical density (O.D.) units. Protein S relative percent concentrations in patient plasma are determined against a curve prepared from a reference plasma provided with the kit. Results obtained from diluted plasma samples not pretreated with polyethylene glycol (PEG) represent the Total Protein S concentration from that sample. To measure Free Protein S, PEG is added to plasma samples prior to beginning the assay to precipitate the Protein S-C4b binding protein complex. The supernatant fraction containing Free Protein S may be tested along with the untreated plasma sample. Both Total (untreated) and Free (PEG-treated) Protein S concentrations are determined following the same assay procedure described using separate reference curves.

The intended use of the device is to quantitatively determine Total and Free Protein S levels (relative to percent of normal concentration) in citrated human plasma. The normal range for Total Protein S for this assay is 60-150%. The normal range for Free Protein S for this assay is 50%-130%. A decreased Protein S activity in plasma may be the result of low concentrations (quantitative or type I deficiency) or only low function (qualitative or type II deficiency). The laboratory diagnosis of Protein S deficiency may require both quantitative and qualitative (functional) determinations.

Test results for clinical samples demonstrate that the performance of the REAADS Protein S Antigen Test Kit and the Helena Protein S Antigen Rocket EID Method and the Helena Free Protein S Reagent is substantially equivalent. The coefficient of correlation (r) for Total Protein

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S is 0.924, with a P-value of 0.494 (by single factor ANOVA). The coefficient of correlation (r) for Free Protein S is 0.934, with a P-value of .346 (by single factor ANOVA). Both results indicate the two methods are statistically similar. Although a few minor differences in value recovery were observed between the assays, in general the performance was comparable. The differences may be attributed to the improved specificity of REAADS ELISA technology when compared to EID.

Marci Deeter

7-30-97

Nanci Dexter Director, Quality and Regulatory Affairs Date

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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 a stylized image of an eagle or bird-like figure with three curved lines representing its body and wings.

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

AUG 1 3 1997

Ms. Nanci Dexter Director Quality and Regulatory Affairs REAADS Medical Products, Inc. 12061 Tejon Street Westminster, CO 80234

K972482/S1 Re : REAADS® Protein S Antigen Test Kit Requlatory Class: II Product Code: GGB Dated: July 30, 1997 Received: August 1, 1997

Dear Ms. Dexter:

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 Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirement, 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 In addition, FDA may publish further announcements action. 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 asdescribed 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

510(k) Number: _______________________________________________________________________________________________________________________________________________________________

Device Name: REAADS Protein S Antigen Test Kit

Indications for Use:

The REAADS Protein S Aitigen Test Kit is an in vitro diagnostic assay for the quantitative determination of Total and Free Protein S levels in human plasma (as a percentration) by enzyme-linked immunosorbent assay (ELISA). Plasma levels of Protein S may be used in conjunction with the results from other assays as an aid in diagnosing congenital or acquired Protein S deficiencies associated with thrombotic disease.

The REAADS Protein S Antigen Test Kit is intended to be used by clinical (hospital and reference) laboratories.

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED) Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
D'vision of Clinical Laboratory Devices
510(k) Number K972453

Regulation Number and Section

§ 864.7290 Factor deficiency test.

(a)
Identification. A factor deficiency test is a device used to diagnose specific coagulation defects, to monitor certain types of therapy, to detect coagulation inhibitors, and to detect a carrier state (a person carrying both a recessive gene for a coagulation factor deficiency such as hemophilia and the corresponding normal gene).(b)
Classification. Class II (performance standards).