K Number
K964185
Device Name
IMX CA 125
Manufacturer
Date Cleared
1997-11-04

(379 days)

Product Code
Regulation Number
866.6010
Panel
IM
Reference & Predicate Devices
N/A
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The IMx® CA 125™ assay is a Microparticle Enzyme Immunoassay (MEIA) for the quantitative measurement of CA 125 assay values in human serum. The IMx® CA 125M assay is to be used as an aid in monitoring response to therapy for patients with epithelial ovarian cancer. Serial testing for patient CA 125 assay values should be used in conjunction with other clinical methods used for monitoring ovarian cancer.

Device Description

IMx CA 125 is a microparticle enzyme immunoassay on the IMx System for the quantitative measurement of CA 125 assay values in human serum. IMx CA 125 employs Abbott Calibrators and Controls.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study details for the IMx® CA 125™ device, based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are not explicitly stated as distinct numerical targets in this document. Instead, the study aims to demonstrate substantial equivalence to a predicate device (ABBOTT CA 125 II™ RIA assay) across several performance metrics. Therefore, the "acceptance criteria" are implied by the performance of the predicate device, and the "reported device performance" shows how the new device compares.

Performance MetricPredicate Device (ABBOTT CA 125 II RIA) Performance (Implied Acceptance Criteria)IMx® CA 125™ Reported Performance
Correlation Coefficient (vs. predicate)Close to 1.0 (ideally >= 0.95 or specific range)0.997
Slope (vs. predicate)Close to 1.0 (ideally between 0.9 and 1.1)0.94
Y-intercept (U/mL) (vs. predicate)Close to 0 (ideally within a small acceptable range)-4.7 U/mL
Dynamic Range0 - 500 U/mL0 - 600 U/mL
Sensitivity0.4 U/mL2 U/mL
Area Under the Curve (ROC analysis)0.800.87
Sensitivity (at 35 U/mL)66.0%64.0%
Specificity (at 35 U/mL)92.0%96.0%
Concordance (at 35 U/mL, Healthy Females)Implicitly high for predicate96.2%
Concordance (at 35 U/mL, Benign Gyn Conditions)Implicitly high for predicate95.6%
Concordance (at 35 U/mL, Ovarian Cancer)Implicitly high for predicate97.0%
Concordance (at 35 U/mL, Total Subjects)Implicitly high for predicate94.1%
Serial Tracking Agreement (Ovarian Cancer Patients)Implicitly good agreement with clinical statusGood agreement for 39 out of 55 patients evaluated (IMx results with clinical status)

2. Sample Size Used for the Test Set and Data Provenance

  • Linear Regression Analysis: 493 specimens
  • Receiver Operating Characteristic (ROC) Analysis: 130 apparently healthy females + 45 patients with benign gynecologic conditions (control groups) + 197 patients with ovarian cancer (disease group). Total: 372 specimens.
  • Concordance Analysis: 130 apparently healthy females, 45 patients with benign gynecologic conditions, 197 patients with ovarian cancer, and 542 total subjects (overlaps with ROC and includes other samples not detailed).
  • Serial Tracking Data: 55 patients with ovarian cancer.
  • Data Provenance: Not explicitly stated (e.g., country of origin, retrospective/prospective). However, given the context of a 510(k) submission in the US, it's highly likely to be U.S.-based clinical samples. It is not explicitly stated whether the studies were retrospective or prospective.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

There is no mention of "experts" being used to establish ground truth for the test set in the same way one might assess imaging data. The ground truth for this diagnostic device is based on established clinical diagnoses (e.g., "apparently healthy females," "patients with benign gynecologic conditions," "patients with ovarian cancer," "clinical status of ovarian cancer patients"). Therefore, experts in establishing ground truth (like radiologists for imaging) are not directly applicable in the terms usually used for device performance. The clinical status of the serial tracking patients would have been determined by treating physicians based on standard clinical practices, but the number and qualifications of these individuals are not specified.

4. Adjudication Method for the Test Set

Not applicable. The ground truth is based on clinical diagnosis or classification of patient groups, not subjective interpretation requiring adjudication of individual results.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done, What was the effect size of how much human readers improve with AI vs without AI assistance

Not applicable. This is a blood-based immunoassay, not an AI-assisted diagnostic imaging device or a device involving human "readers" in the context of MRMC studies.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done

Yes, the studies reported are standalone performance of the IMx® CA 125™ assay. It directly measures the CA 125 assay values in human serum and compares these quantitative results to those of the predicate device and relevant clinical categories. There is no explicit human-in-the-loop component discussed for the performance evaluation itself, although the results are intended to aid clinicians.

7. The Type of Ground Truth Used

The ground truth used is primarily clinical diagnosis/classification and clinical status (for monitoring).

  • For ROC analysis, ground truth was "apparently healthy," "benign gynecologic conditions," and "ovarian cancer."
  • For serial tracking, ground truth was the "clinical status" of ovarian cancer patients.
  • For comparisons with the predicate, the predicate device's results serve as a reference point for correlation, slope, and intercept analysis.

8. The Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of machine learning or algorithm development. This immunoassay is a chemical detection system, not an AI/ML algorithm that requires training. The 493 specimens used for linear regression and the 372 specimens for ROC analysis are essentially the test set used to demonstrate performance for substantial equivalence.

9. How the Ground Truth for the Training Set Was Established

Not applicable, as there is no mention of a training set for an AI/ML algorithm.

§ 866.6010 Tumor-associated antigen immunological test system.

(a)
Identification. A tumor-associated antigen immunological test system is a device that consists of reagents used to qualitatively or quantitatively measure, by immunochemical techniques, tumor-associated antigens in serum, plasma, urine, or other body fluids. This device is intended as an aid in monitoring patients for disease progress or response to therapy or for the detection of recurrent or residual disease.(b)
Classification. Class II (special controls). Tumor markers must comply with the following special controls: (1) A guidance document entitled “Guidance Document for the Submission of Tumor Associated Antigen Premarket Notifications (510(k)s) to FDA,” and (2) voluntary assay performance standards issued by the National Committee on Clinical Laboratory Standards.