The anti Cardiolipin Screen is indicated for the screening of patient serum for the presence of IgG, IgM, and IgA autoantibodies to cardiolipin . Autoantibodies to aCl are typically observed in patients with systemic lupus erythematosus and other connective tissue diseases. This assay is intended to be utilized as an aid in the diagnosis of antiphospholipid syndrome.

Device Description

The ELISA methodology is commonly used for serum antibody evaluations. In this assay, purified bovine cardiolipin has been attached to the inner surfaces of microplate test wells by the manufacturer. The user adds diluted patient samples to the wells. Anticardiolipin antibodies in patient serum bind specifically to the cardiolipin antigen attached to the plate, and remain in place after a wash step.

A trivalent second antibody cocktail, consisting of peroxidase-conjugated goat anti-human IgG (Fc), IgM (u), and IgA (α), is added to the wells. After an incubation/wash step, TMB (tetramethylbenzidine) substrate is added. In the wells containing bound cardiolipin-anticardiolipin complexes, the peroxidase enzyme catalyzes a color change in the TMB substrate. After the reaction is stopped with dilute sulfuric acid, the color is read in an ELISA plate reader. Optical densities (ODs) of patient samples are compared to the OD of a reference serum included in the kit.

AI/ML Overview

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

Device: Hemagen® aCL Screen anti Cardiolipin screening assay
Intended Use: Qualitative detection of IgG, IgM, and IgA autoantibodies to cardiolipin in human serum. Aid in the diagnosis of antiphospholipid syndrome.

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria (e.g., "The device must achieve X% sensitivity and Y% specificity"). Instead, it presents the results of comparison testing to demonstrate substantial equivalence to predicate devices. The values presented below are the reported performance from this comparison.

Metric	Acceptance Criteria (Implicit/Reported)	Reported Device Performance
Relative Analytical Sensitivity	Not explicitly stated; demonstrated through comparison to predicate devices	100% (39/39) with 95% CI: 91.0% to 100% (Combined Panels)
Relative Analytical Specificity	Not explicitly stated; demonstrated through comparison to predicate devices	92.3% (72/78) with 95% CI: 84.2% to 96.4% (Combined Panels)
Inter-assay Precision (CV)	Not explicitly stated	6.9% - 13.0%
Intra-assay Precision (CV)	Not explicitly stated	6.5% - 15.0%

2. Sample Size and Data Provenance for Test Set

Sample Size for Test Set: 117 serum specimens
- 38 (or 39 in combined table) samples from "patients positive for aCl" (Positive Panel)
- 79 samples from "normal blood donors" (Normal Panels)
Data Provenance: Not explicitly stated (e.g., country of origin). The document implies these were patient and normal donor samples, but does not specify if they were retrospective or prospective, or from what geographic region.

3. Number of Experts and Qualifications for Ground Truth (Test Set)

Number of Experts: Not applicable/not mentioned.
Qualifications of Experts: Not applicable/not mentioned.
- The ground truth for the test set was established by comparison to predicate devices (Hemagen® Anti-Cardiolipin IgG and IgM, and Hemagen® Anti-Cardiolipin IgA Calibrator Reagents). This implies the predicate devices themselves served as the "expert" or reference standard for classification of whether a sample was positive or negative for aCl.

4. Adjudication Method for Test Set

Adjudication Method: Not applicable. The samples were classified as "POS" or "NEG" based on the predicate devices. There was no mention of human expert adjudication or consensus methods used to resolve discrepancies between different interpretations or tests, beyond the direct comparison to the predicate devices.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

MRMC Study: No, an MRMC comparative effectiveness study was not done. This device is an immunoassay, not an imaging or diagnostic device requiring human reader interpretation in the same way. The study focuses on comparing the new device's analytical performance against existing predicate devices.

6. Standalone (Algorithm Only) Performance

Standalone Performance: Yes, the described "Comparison Testing" section directly details the standalone performance of the Hemagen® aCL Screen. It compares the device's output (positive/negative) directly against the results obtained from the predicate devices which serve as the reference for classification. There is no human-in-the-loop performance described, as this is an automated immunoassay.

7. Type of Ground Truth Used

Type of Ground Truth: The ground truth for the comparison testing was established by comparison with predicate devices. Specifically, samples were categorized as "positive for aCl" or from "normal blood donors," and the results from the proposed device were compared to the results from the legally marketed Hemagen® Anti-Cardiolipin IgG and IgM assays, and the Hemagen® Anti-Cardiolipin IgA Calibrator Reagents. This is an example of using a reference standard (predicate devices) to define the truth.

8. Sample Size for Training Set

Sample Size for Training Set: Not explicitly stated as a distinct "training set." The 117 serum specimens mentioned in Section II ("Cutoff Serum Standardization") and Section III ("Comparison Testing") appear to be the primary dataset used for both optimizing the cutoff and evaluating the device's performance against predicates. It's possible the "Cutoff Serum Standardization" phase where ROC techniques were used could be considered a form of training or optimization, but a separate, distinct "training set" versus "test set" paradigm is not clearly delineated beyond this.

9. How Ground Truth for Training Set was Established

How Ground Truth for Training Set was Established: For the "Cutoff Serum Standardization," where an optimized cutoff OD was derived:
- 117 serum specimens from both "disease state and normal patient panels" were screened concurrently with both the proposed and predicate devices.
- Receiver Operating Characteristic (ROC) techniques were employed to analyze the data from this concurrent testing.
- The "optimized cutoff OD" was determined based on this ROC analysis and comparison testing relative to the predicate devices, aiming for a "relative analytical sensitivity of ≥ 97.0 %" (which became 100% in the final comparison). This indicates that the predicate devices' classifications likely served as the ground truth or gold standard against which the new device's performance was optimized.

Summary

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K971039

510(k) Summary

Submitter's Name/Contact Person

JUN - 3 1997

Joseph M. Califano, Regulatory Affairs Manager

Address

Hemagen Diagnostics, Inc. 34-40 Bear Hill Road Waltham, MA, 02154 (617) 890-3766 Phone No: (617) 890-3748 Fax No: jcalifano@hemagen.com e-mail:

Date Prepared

7 March 1997

2 Device Names

Trade Name: Hemagen ® aCL Screen anti Cardiolipin screening assay Common Name: Immunological test system, multiple Classification Name: autoantibodies {21 CFR 866.5660}

3 Predicate Device(s)

Hemagen ® Anti-Cardiolipin IgG and IgM {EIA method} a. Reference 510 (k) Docket No. K 932373
Hemagen ® Anti-Cardiolipin IgA Calibrator Reagents {EIA method} b. Reference 510 (k) Docket No. K 941840

510(k) Summary - Page 1

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Description of Device 4

5 Intended Use of Device

The device is intended for the qualitative detection of IqG. IgM, and IgA autoantibodies to cardiolipin in human serum.

Performance Data ర్.

1. Trivalent HRP Coniugate Standardization

IgG, IgM, and IgA standard preparations (Louisville APL Diagnostics, Inc.) were diluted in Serum Diluent and tested with the predicate devices to establish standard curves. Optimal second antibody concentrations were established by titration for each monovalent HRP conjugate. The three conjugates were then blended, verified against the standard calibration curves, and freeze-dried.

II. Cutoff Serum Standardization

117 serum specimens from both disease state and normal patient panels were screened concurrently with both the proposed and predicate devices. Receiver Operating Characteristic {ROC}techniques were used to derive an optimized cutoff OD to be utilized in the preparation of the Cutoff Serum. Based upon this analysis and comparison testing, the optimized cutoff OD has demonstrated a relative analytical sensitivity of ≥ 97.0 %

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III. Comparison Testing

TOTAL

The Hemagen ® antiCardiolipin Screen , the Hemagen ® Anti-Cardiolipin IgG/ IgM assays, and the Hemagen ® Anti-Cardiolipin IgA Calibrator Reagents were used to concurrently assay serum specimens from patients positive for aCl, and from normal blood donors. A total of 117 samples were evaluated.

Table 1: Positive Panel, N = 38
Predicate Devices
	POS	NEG	TOTAL
ProposedDevice	POS	38	0	38
	NEG	0	0	0
TOTAL		38	0	38
Relative analytical sensitivity = 100% {38/38}, 0.95 INTERVAL 90.8% to 100%
Table 2: Normal Panels, N=79
Predicate Devices
	POS	NEG	TOTAL
ProposedDevice	POS	1	6	7
	NEG	0	72	72
TOTAL		1	78	79
The indeterminate samples were retested with the proposed device.
The relative analytical specificity 92.3 % {72/78}, 0.95 INTERVAL 84.2% to 96.4 %
Table 3: Combined Panels, N = 117
Predicate Devices
	POS	NEG	TOTAL
ProposedDevice	POS	39	6	45
	NEG	0	72	72

Relative sensitivity = 100 % {39/39} , 0.95 INTERVAL 91.0 % to 100 % Relative specificity 92.3 % {72/78} , 0.95 "NTERVAL 84.2 % to 96.4 %

117

510(k) Summary - Page 3

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IV. A. Precision

To evaluate anti Cardiolipin Screen precision, inter-assay and intra-assay studies were conducted.

Inter-assay precision

Three serum samples with various levels of anticardiolipin (negative, low positive, and high positive), the Cutoff Serum, and the Positive Control were assayed five times each, twice a day, on five different days:

Sample	Mean OD	Std. Dev.	CV
Negative	0.059	0.007	12.3 %
Low Positive	0.197	0.023	11.7 %
High Positive	0.967	0.067	6.9 %
Cutoff Serum	0.115	0.015	13.0 %
Positive Control	0.697	0.074	10.7 %

Intra-assay precision

Three serum samples with various levels of anticardiolipin (negative, low positive, and high positive) were assayed 16 consecutive times in a single run:

Sample	Mean OD	Std. Dev.	CV
Negative	0.069	0.010	15.0 %
Low Positive	0.306	0.022	7.1 %
High Positive	1.112	0.072	6.5 %

Conclusions

The results of the comparative studies support the claim that the Hemagen ® anti Cardiolipin Screen is substantially equivalent to the comparative devices, and performs as an effective screening assay for the detection of autoantibodies to anticardiolipin IgA, IgG, and IgM in human serum.

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Food and Drug Administration 2098 Gaither Road Rockville MD 20850

JUN - 3 1997

Mr. Joseph M. Califano Manager, Regulatory Affairs Hemagen Diagnostics, Inc. 34-40 Bear Hill Road ---Waltham, Massachusetts 02154

K971039 Re: Trade Name: Hemagen® aCL Screen Regulatory Class: II Product Code: MID Dated: March 20, 1997 Received: March 21, 1997

Dear Mr. Califano:

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 of the Act. The general controls provisions 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 Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 820) and that, through periodic GMP 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 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.

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.

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Page 2

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 at (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html"

Sincerely yours,

Steven Autman

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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Indication(s) For Use

18 11 11 11 11

(PLEASE DO NOT WRITE BELOW THIS LINE)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Peter E. Massim

on of Di 51 Offe) Number

Prescription Use (Per 21 CFR 801.109)

Over-The-Counter-Use

Regulation Number and Section

§ 866.5660 Multiple autoantibodies immunological test system.

(a)
Identification. A multiple autoantibodies immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoantibodies (antibodies produced against the body's own tissues) in serum and other body fluids. Measurement of multiple autoantibodies aids in the diagnosis of autoimmune disorders (disease produced when the body's own tissues are injured by autoantibodies).(b)
Classification. Class II (performance standards).