The Thermo Electron CT OIA assay is an Optical ImmunoAssay (OIA) test for the rapid, qualitative detection of chlamydial antigen from female endocervical swab specimens. This test is intended for in vitro diagnostic use as an aid in identifying the presence of Chlamydia trachomatis antigen. The assay is intended for in vitro diagnostic use with symptomatic females in populations at risk for sexually transmitted diseases.

CT OIA test results are presumptive evidence for either the presence or absence of C. trachomatis. Definitive laboratory evidence for the presence/ absence of C. trachomatis would need additional testing. CT OIA test results should not preclude empiric treatment of women with overt symptoms of PID. Performance for use in asymptomatic male and female populations has not been established.

Device Description

The CT OIA test involves the qualitative extraction of antigen specific to the Chlamydia genus. The Optical ImmunoAssay technology enables the direct visual detection of a physical change in the optical thickness of molecular thin films. This change is a result of antigen-antibody binding on an optical surface (silicon wafer). When an extracted specimen is placed directly on the optical surface, the immobilized specific antibodies capture the antigen. After washing, the substrate is added, increasing the thickness (mass enhancement) of the molecular thin film. This change in thickness alters the reflected light path and is visually perceived as a color change. Slight changes in optical thickness produce a distinct, visible color change. A positive result appears as a purple spot on the predominant gold background. When antigen is not present in the specimen, no binding takes place. Therefore, the optical thickness remains unchanged and the surface retains the original gold color indicating a negative result.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study information for the Thermo Flectron CT OIA device, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria for clinical performance (e.g., "Sensitivity must be >= X%, Specificity must be >= Y%"). Instead, it reports the observed performance characteristics. Given this, the table will present the key performance metrics as reported in the study:

Metric	Reported Device Performance (%)
Clinical Sensitivity	73.8
Clinical Specificity	98.4
Overall PPV	87.3
Overall NPV	96.2
Reproducibility	87.7

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

Sample Size for Clinical Sensitivity and Specificity: 767 symptomatic female patients were included in the final analysis. (Initially, 885 female patients were enrolled, but 118 were excluded).
Sample Size for Reproducibility: Reproducibility testing was performed on three blinded panels, though the exact number of individual samples within these panels isn't specified (71/81 successful tests are mentioned, suggesting 81 blinded samples).
Data Provenance: The study was a "multicenter study at four geographically diverse clinical sites" located in the Northwest, Midwest, Mid-Atlantic, and Southeast regions of the United States. It was a prospective study as patients were enrolled and tested.

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

The document does not specify the number or qualifications of experts involved in establishing the ground truth.

4. Adjudication Method for the Test Set

The document does not explicitly mention an adjudication method. For the clinical sensitivity and specificity study, the CT OIA test was compared to a "commercially available LCx nucleic acid amplification test for C. trachomatis" as the primary reference method. "Secondary confirmation testing of positive OIA was done by a commercially available PCR test." This suggests a two-step approach for ground truth, but not an adjudication process among human readers.

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

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not performed. The study focuses on the standalone performance of the device compared to a reference method, not on how human readers' performance improves with or without AI assistance.

6. Standalone (Algorithm only without human-in-the-loop performance) Study

Yes, a standalone study was conducted. The performance metrics (sensitivity, specificity, PPV, NPV) reported are for the CT OIA assay itself, in comparison to a reference method (LCx and PCR), without human interpretation as part of the primary device output. The device itself is an "Optical ImmunoAssay technology [that] enables the direct visual detection of a physical change in the optical thickness... visually perceived as a color change. A positive result appears as a purple spot on the predominant gold background." While a human observes this color change, the reported performance is for the diagnostic test's ability to accurately reflect the presence of the antigen, not for a human's ability to interpret an image provided by an AI.

7. Type of Ground Truth Used

The primary ground truth for the clinical sensitivity and specificity study was a commercially available LCx Nucleic Acid Amplification Test (NAAT) for C. trachomatis. Positive OIA results were also subject to secondary confirmation testing by a commercially available PCR test.

8. Sample Size for the Training Set

The document does not mention a separate "training set" or "training data" in the context of developing the CT OIA assay. This assay is a diagnostic test based on Optical ImmunoAssay technology, likely developed and validated through laboratory experimentation and calibration rather than machine learning on a large dataset. Therefore, the concept of a training set for an algorithm is not applicable here.

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

As noted above, the concept of a training set as understood in AI/ML is not applicable. The device's development would involve establishing its analytical performance characteristics (e.g., detection limits, cross-reactivity) through laboratory studies using characterized samples, rather than establishing "ground truth" for a training set in a clinical context.

Summary

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$\K_032330$

Thermo Flectron CT OLA 510(k) July, 2003 Page 11 of 560

3/2/04

510(k) SUMMARY (page 1 of 3) 8.0

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.

K032330 The assigned 510(k) number is: __

A. Safety and effectiveness information required per [§807.92(a)(1)]:

SUBMITTER'S NAME: Thermo BioStar, Inc. ●
ADDRESS: 331 South 104th Street, Louisville, CO 80027 .
TELEPHONE: (303) 530-3888 ext. 612 .
FAX: (303) 581-6405 .
CONTACT PERSON: John G. Adams .
DATE 510(k) SUMMARY PREPARED: June, 2003 .

B. Safety and effectiveness information required per [§807.92(a)(2)]:

TRADE OR PROPRIETARY NAME: CT OLA .
COMMON NAME: Chiamydia antigen assay .
CLASSIFICATION NAME: Antigen, Enzyme Linked Immunoabsorbent Assay, Chlamydia .

C. Identification of legally marketed device to which we are comparing performance.

· Thermo Biostar Chlamydia OIA
· Intended use of device [§807.92(a)(5)]:

The BioStar® brand CT OIA® assay is an Optical ImmunoAssay test for the rapid qualitative detection of chlamydia antigen from female endocervical swab specimens. This test is intended for in vitro diagnostic use as an aid in identifying the presence of Chlamydia trachomatis antigen. The assay is intended for use with symptomatic females in populations at risk for sexually transmitted diseases.

D. Description of device [§807.92(a)(4)]:

Principle of the Test:

8.0 510(k) SUMMARY (page 2 of 3)

DEVICE COMPARISON:

The CT OIA assay is similar to the Chlamydia OIA assay method in that:

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Both assays are rapid diagnostic tests that utilize Optical Immunoassay technology ●
Both assays are used to detect and identify lipopolysaccharide antigen specific to Chlamydia genus. .
Both assays detect lipopolysaccharide antigen specific to Chlamydia genus in female endocervical swabs .
Both assays can provide results in less than 30 minutes. .
. Both assays are qualitative.

The CT OIA assay differs from the currently marketed Chlamydia OLA in that:

CT OIA assay procedure has been revised and streamlined from that recommended for the original Chalamydia . test
The CT OIA test clinical performance has been compared to the LCR (Ligase Chain Reaction) assay as a . reference method, whereas the original test was compared against microbiology culture.

SUMMARY OF PERFORMANCE DATA:

CLINICAL STUDIES

Performance characteristics for the CT OIA assay were initially established in a multicenter study at four geographically diverse clinical sites.

H. Summary of clinical testing [§807.92(b)(2)]:

Reproducibility

Swab: Reproducibility testing was conducted at three physician office laboratories. Swab testing was performed on three blinded panels at three separate times at each institution. External kit positive and negative controls were also included in the study. There were no significant differences in performance among the sites. Overall reproducibility was 87.7% for the blinded samples (71/81), and 100% for the external control samples (18/18).

Clinical Sensitivity and Specificity

A study was conducted comparing the CT OIA test to a commercially available LCx nucleic acid amplification test for C. trachomatis. Secondary confirmation testing of positive OIA was done by a commercially available PCR test. A total of 1725 paients were enrolled into a multicenter study testing for both chlamydia and gonorrhoeae antigens, in male and female patients. For the purposes of this submission, data is presented from the 885 female patients cnrolled. A total of 118 patients were excluded during the analysis, resulting in data from a otal of 767 asymptomatic and symptomatic female patients included in the final analysis.

The CT OIA assay was evaluated versus LCx at four clinical trial sites (central hospital labs) located in the Northwest, Midwest, Mid-Atlantic and Southeast regions of the United States. A total of 885 female patients suspected of having, or with a history of C. trachomatis were evaluated by the CT OIA test as compared to the LCx test method. Data for the symptomatic enrollees (499) are presented in support of this submission. Sensitivity and specificity for symptomatic female endocervical swabs was 73.8% and 98.4% respectively. Overall PPV and NPV for symptomatic females was 87.3% and 96.2% respectively.

I. Conclusions from nonclinical / clinical testing [§807.92(b)(3)]:
The results of the above described internal and external studies demonstrate that the CT OIA test is as safe and effective as the comparative device.
J. Additional information [§807.92(d)]:
No additional information has been requested by FDA at this time.

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Image /page/2/Picture/0 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized depiction of an eagle or bird-like figure with three curved lines representing its body and wings. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES U.S.A." is arranged in a semi-circular fashion around the bird symbol.

DEPARTMENT OF HEALTH & HUMAN SERVICES

Public Health Service

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Mr. John G. Adams Thermo BioStar Regulatory Affairs Thermo Electron Corporation 331 South 104th Street Louisville, CO 80027

Re: K032330

Trade/Device Name: CT OIA® Regulation Number: 21 CFR 866.3120 Regulation Name: Chlamydia Serological Reagents Regulatory Class: Class I Product Code: LJC Dated: December 19, 2003 Received: December 22, 2003

Dear Mr. Adams:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have 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 devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). 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.

MAR - 2 2004

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 be found in Title 21, Code 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 that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes 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 20).

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Page 2

This letter will allow you to begin marketing your device as described in your Section 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 information about the application of labeling requirements to your device, or questions on the promotion 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 Division 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.

Salaatts

Sally A. Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known): K032330

Device Name: CT OIA®

Indications For Use:

Prescription Use _ × (Part 21 CFR 801 Subpart D)

AND/OR

Over-The-Counter Use (21 CFR 807 Subpart C)

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

Concurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)

Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

KO 32330 510(k) _

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Regulation Number and Section

§ 866.3120 Chlamydia serological reagents.

(a)
Identification. Chlamydia serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies to chlamydia in serum. Additionally, some of these reagents consist of chlamydia antisera conjugated with a fluorescent dye used to identify chlamydia directly from clinical specimens or cultured isolates derived from clinical specimens. The identification aids in the diagnosis of disease caused by bacteria belonging to the genusChlamydia and provides epidemiological information on these diseases. Chlamydia are the causative agents of psittacosis (a form of pneumonia), lymphogranuloma venereum (a venereal disease), and trachoma (a chronic disease of the eye and eyelid).(b)
Classification. Class I (general controls).