← Product Code [LJP](/submissions/MI/subpart-d%E2%80%94serological-reagents/LJP) · K063675

# DIAGNOSTIC HYBRIDS' D3 DFA CHLAMYDIAE CULTURE CONFIRMATION KIT (K063675)

_Diagnostic Hybrids, Inc. · LJP · Sep 24, 2007 · Microbiology · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/MI/subpart-d%E2%80%94serological-reagents/LJP/K063675

## Device Facts

- **Applicant:** Diagnostic Hybrids, Inc.
- **Product Code:** [LJP](/submissions/MI/subpart-d%E2%80%94serological-reagents/LJP.md)
- **Decision Date:** Sep 24, 2007
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 866.3120
- **Device Class:** Class 1
- **Review Panel:** Microbiology

## Indications for Use

The Diagnostic Hybrids' D³ DFA Chlamydiae Culture Confirmation Kit is intended for the qualitative detection of Chlamydiae lipopolysaccharide (LPS) in inoculated cell cultures by immunofluorescence using fluoresceinated monoclonal antibodies (MAbs). Performance has not been established with direct patient specimens.

## Device Story

Kit uses murine monoclonal antibodies (MAbs) conjugated with fluorescein to detect Chlamydiae lipopolysaccharide (LPS) in cell cultures inoculated with patient specimens. Procedure involves fixing cell cultures in acetone, adding DFA reagent, incubating at 35-37°C for 48-72 hours, and counterstaining uninfected cells with Evan’s Blue. Prepared slides are examined via fluorescence microscope (490nm excitation/520nm emission). Positive result indicated by bright, apple-green fluorescence in infected cells; uninfected cells appear dull red. Used in clinical laboratory settings by trained personnel to confirm Chlamydiae isolation from patient specimens (swabs in transport medium). Provides definitive identification of Chlamydiae in culture, aiding clinical diagnosis of Chlamydia infection.

## Clinical Evidence

Performance evaluated via method comparison study across four sites using 994 specimens (prospective and archived). Compared against three predicate devices. Prospective study (n=661) showed PPA of 95.5% (95% CI: 84.5-99.4%) and NPA of 99.4% (95% CI: 98.3-99.8%). Archival specimen testing (n=213) showed 100% PPA and 100% NPA. Additional site-specific comparisons against PathoDx and Pathfinder showed 100% PPA and 99.0-100% NPA. Analytical sensitivity was equivalent to predicate (~0.7-1.4 TCID50). Analytical specificity testing showed no cross-reactivity with 57 viruses, 20 cell types, or various bacteria/yeast/protozoa, except for S. aureus (distinguishable by morphology).

## Technological Characteristics

Immunofluorescence assay using fluorescein isothiocyanate (FITC) labeled murine monoclonal antibodies. Kit includes DFA reagent (MAbs, Evan's Blue counter-stain, 0.1% sodium azide), antigen control slides, PBS concentrate, and mounting fluid. Requires fluorescence microscope with FITC filter set (100-400X). Manual procedure involving cell fixation, incubation, and visual inspection.

## Regulatory 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 genus Chlamydia 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).

## Predicate Devices

- American Microscan DFA Chlamydia Detection Kit ([K864389](/device/K864389.md))
- Kallestad Pathfinder® Chlamydia Culture Confirmation Kit/System ([K864663](/device/K864663.md))
- Diagnostic Products, Corp. PathoDx® Chlamydia Culture Confirmation Kit ([K895839](/device/K895839.md))

## Submission Summary (Full Text)

> This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com.
>
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# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE

A. 510(k) Number: K063675
B. Purpose for Submission: The 510(k) holder would like to introduce D³ DFA Chlamydiae Culture Confirmation Kit into interstate commerce.
C. Measurand: Chlamydiae lipopolysaccharide antigen
D. Type of Test: Determination of the presence of Chlamydiae amplified in cell culture by immunofluorescence using fluoresceinated monoclonal antibodies
E. Applicant: Diagnostic Hybrids, Inc.
F. Proprietary and Established Names: Diagnostic Hybrids' D³ DFA Chlamydiae Culture Confirmation Kit

## G. Regulatory Information:

1. Regulation section: 21CFR 866.3120, Chlamydia serological reagents
2. Classification: Class I
3. Product code: LJP – Antiserum, fluorescent, Chlamydia trachomatis
4. Panel: Microbiology (83)

|  Product Code | Classification | Regulation Section | Panel  |
| --- | --- | --- | --- |
|  LJP | Class I | 21CFR 866.3120 | Microbiology (83)  |

## H. Intended Use:

1. Intended use(s): The Diagnostic Hybrids' D³ DFA Chlamydiae Culture Confirmation Kit is intended for the qualitative detection of Chlamydiae lipopolysaccharide (LPS) in inoculated cell cultures by immunofluorescence using fluoresceinated monoclonal antibodies (MAbs). Performance has not been established with direct patient specimens.
2. Indication(s) for use: Same as Intended Use.
3. Special conditions for use statement(s): For prescription use only
4. Special instrument requirements: Fluorescence microscope with the correct filter combination for FITC (excitation peak = 490 nm, emission peak = 520nm).

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# I. Device Description:

The Diagnostic Hybrids'  $\mathrm{D}^3$  DFA Chlamydiae Culture Confirmation Kit includes a Chlamydiae DFA Reagent that contains a blend of two murine MAbs directed against epitopes on the lipopolysaccharide of Chlamydiae. The kit is used for Chlamydiae identification in cell cultures inoculated with patient specimens.

# J. Substantial Equivalence Information:

1. Predicate device names:

a. American Microscan (distributed by Trinity Biotech) DFA Chlamydia Detection Kit
b. Kallestad (distributed by BioRad) Pathfinder® Chlamydia Culture Confirmation Kit/System
c. Diagnostic Products, Corp. (distributed by Remel) PathoDx® Chlamydia Culture Confirmation Kit

2. Predicate K numbers:

a. K864389
b. K864663
c. K895839

3. Comparison with predicate:

The similarities (Table 1) to the predicate devices are in Intended Use, operating principle, basic design, materials and formulation. All kits use standard immunofluorescence assay techniques for staining fixed, cultured cell monolayers following incubation for Chlamydiae isolation. The kits employ MAbs specific for the lipopolysaccharide of Chlamydiae as the detector antibodies and utilize fluorescein as the fluorophore enabling visualization of the infected cells.

Table 1 Similarities to Comparison Devices

|  Similarities  |   |   |
| --- | --- | --- |
|  Item | Device | Comparison Device  |
|  Intended Use | For the qualitative detection of Chlamydiae lipopolysaccharide (LPS) in inoculated cell cultures by immunofluorescence using fluoresceinated monoclonal antibodies (MAbs). Performance has not been established with direct patient specimens. | a. American Microscan b. Kallestad c. Diagnostic Products, Corp.  |
|  Basic principle | Direct Fluorescent Antibody (DFA) test -Immunofluorescence using fluoresceinated MAbs | a. American Microscan b. Kallestad c. Diagnostic Products, Corp.  |
|  Antibody Antigen | Murine monoclonal antibodies against epitopes of the lipopolysaccharide of Chlamydiae Lipopolysaccharide | a. American Microscan b. Kallestad c. Diagnostic Products, Corp.  |

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|  Similarities  |   |   |
| --- | --- | --- |
|  Item | Device | Comparison Device  |
|  Instrumentation (required but not provided) | Fluorescence microscope with filter combination for fluorescein (excitation peak = 490 nm, emission peak = 520nm). | a. American Microscan
b. Kallestad
c. Diagnostic Products, Corp.  |
|  Sample type | Swab in Transport Medium | a. American Microscan
b. Kallestad
c. Diagnostic Products, Corp.  |

K. Standard/Guidance Document Referenced (if applicable): N/A

L. Test Principle:

The test kit uses Chlamydiae antigen-specific murine monoclonal antibodies (MAbs) that are directly labeled with fluorescein for rapid detection of Chlamydiae which are directed against epitopes on the lipopolysaccharide of Chlamydiae.

The cell cultures to be tested are fixed in acetone. The Chlamydiae DFA Reagent is added to the cells to determine the presence of chlamydial antigens. After incubating at 35°C to 37°C for 48 to 72 hours, the infected cells are stained with a fluorescein conjugated MAb while uninfected cells are counterstained with an Evan’s Blue dye. The stained cells are rinsed with the diluted PBS Concentrate, a drop of the supplied Mounting Fluid is added and a cover slip is placed on the prepared cells. The cells are examined using a fluorescence microscope.

Interpretation of results: It is recommended that controls be examined first to ensure proper test performance before examination of the specimens. A result is considered positive when bright, apple-green fluorescence is observed in the infected cells. If fluorescent cells are found, indicating a Chlamydia-positive specimen, it should be reported as, “Chlamydia isolated by cell culture.” Uninfected cells will stain dull red due to the Evan’s Blue counter-stain included in this device. The entire monolayer of cells must be examined for Chlamydiae-infected, fluorescent cells. If no fluorescent cells are found, the results of testing of the specimen should be reported as, “No Chlamydia detected.”

M. Performance Characteristics (if/when applicable):

1. Analytical performance:

a. Precision/Reproducibility: Not applicable
b. Linearity/assay reportable range: Not applicable
c. Traceability, Stability, Expected values (controls, calibrators, or methods): Not applicable

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# d. Analytical Sensitivity:

Analytical sensitivity was determined by inoculating two 96-well cell culture plates with Chlamydia trachomatis diluted to one (1)  $\mathrm{TCID}_{50}$  per well for the entire plate. The plates were incubated at  $37^{\circ}\mathrm{C}$  for 48 hours and then stained with either the Subject MAbs or the Predicate, Chlamydia CC FA Kit (Trinity). Both plates were stained using the procedure in the respective product insert. This assay was performed 3 times with an average of 36 positive wells detected with the subject MAbs and an average of 37 positive wells with the predicate. These results are not statistically different by a paired t-test.

C. trachomatis was diluted to a value of  $\sim 350\mathrm{TCID}_{50}$  and serial 2-fold dilutions were then made to a final value of  $\sim 0.7\mathrm{TCID}_{50}$ . Each dilution of C. trachomatis was inoculated into 6 McCoy shell vials, centrifuged at  $700\mathrm{xg}$  for 60 minutes and incubated at  $35 - 37^{\circ}\mathrm{C}$  for 48 hours. The subject MAbs or the predicate, Chlamydia CC FA Kit (Trinity), was used to stain 3 shell vials of each C. trachomatis dilution according to the product inserts. The sensitivity of both fluorescent antibody stains is substantially equivalent, with  $\sim 0.7 - 1.4$ $\mathrm{TCID}_{50}$  as the minimum C. trachomatis dilution detected, as indicated by at least one cover slip having no detectable infection.

# e. Analytical specificity:

The Chlamydiae DFA Reagent was tested for its ability to detect in cell culture the 15 known serovars of Chlamydia trachomatis as well as the C. psittaci and C. pneumoniae. Cell cultures (McCoy, BGMK, or HEp-2) were inoculated with approximately  $1.5 \times 10^{6}$  infective units of Chlamydia trachomatis, Chlamydophila psittaci, or Chlamydophila pneumoniae, and incubated for 2 days to yield a  $3+$  to  $4+$  infection. Cultures were processed and stained with the Chlamydia DFA Reagent or specially prepared DFA reagents containing only one of the Chlamydia MAbs. The MAbs were found to react with all organisms tested, as presented in Table 2

Table 2 Chlamydiae Tested for Reactivity with  $\mathrm{D}^3$  DFA Chlamydiae Culture Confirmation Kit

|  CHLAMYDIAE | Serovar | Inoculum (Infective units per culture) | Result (Reactive+) (Negative -)  |
| --- | --- | --- | --- |
|  Chlamydia trachomatis | A | 1.5 x 106 | +  |
|   |  B | 1.5 x 106 | +  |
|   |  C | 1.5 x 106 | +  |
|   |  D | 1.5 x 106 | +  |
|   |  E | 1.5 x 106 | +  |
|   |  F | 1.5 x 106 | +  |
|   |  G | 1.5 x 106 | +  |
|   |  H | 1.5 x 106 | +  |
|   |  I | 1.5 x 106 | +  |
|   |  J | 1.5 x 106 | +  |

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The Chlamydiae DFA Reagent was also tested for cross-reactivity against 57 virus strains (cultured and processed for staining), 20 host culture cell types, one yeast, one protozoa, and 28 bacterial cultures including Staphylococcus aureus, a protein-A-producing bacterium. The DFAs were prepared at  $1.5\mathrm{X}$  the concentration that is provided in the kit. Each of the tested viruses was prepared as infected cell monolayers, 150 to 2100  $\mathrm{TCID}_{50}$ . Bacterial strains were cultured, processed as suspensions, then spotted on microscope slides at concentrations ranging from  $6.4\times 10^{4}$  to  $2.93\times 10^{7}$  cfu per well in a  $10~\mu \mathrm{L}$  dot, then stained with the  $1.5\mathrm{X}$  DFAs according to the procedure in the product insert. Cell cultures were stained as confluent monolayers. No cross-reactivity was observed with all tested microorganisms and cell cultures except the S. aureus, which generated small points of fluorescence. Protein A specifically binds to the Fc portions of conjugated antibodies. Such binding can be distinguished from viral antigen binding on the basis of morphology, i.e., S. aureus-bound fluorescence appears as small,  $\sim 1$  micron diameter, bright dots.

Table 3 Cell Lines and Viruses Cross-reactivity Testing

|  Organism | Strain or Type | Lot Number | Chlamydiae DFA Reagent | TCID50 or CFU  |
| --- | --- | --- | --- | --- |
|  Cell Line | A-549 | C560316 | - | n/a  |
|  Cell Line | BGMK | C530316 | - | n/a  |
|  Cell Line | HEp-2 | C570316 | - | n/a  |
|  Cell Line | HFF (Hs27) | C870315 | - | n/a  |
|  Cell Line | LLC-MK2 | C860316S | - | n/a  |
|  Cell Line | McCoy | C540316 | - | n/a  |
|  Cell Line | MDCK | C830316S | - | n/a  |
|  Cell Line | MRC-5 | C510315A | - | n/a  |
|  Cell Line | MRHF | C440314 | - | n/a  |
|  Cell Line | Mv1Lu | C580317S | - | n/a  |
|  Cell Line | NCI-H292 | C590313S | - | n/a  |
|  Cell Line | pCMK | 470309 | - | n/a  |
|  Cell Line | pRhMK | A490310 | - | n/a  |
|  Cell Line | RD | C760317S | - | n/a  |
|  Cell Line | RhMK II | 490311YS | - | n/a  |

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|  Cell Line | RK (passage 1) | C480314PS | - | n/a  |
| --- | --- | --- | --- | --- |
|  Cell Line | R-Mix | C960314S | - | n/a  |
|  Cell Line | Vero | C840331S | - | n/a  |
|  Cell Line | Vero 76 | C670329S | - | n/a  |
|  Cell Line | WI-38 | 850318W | - | n/a  |
|  |   |   |   |   |
|  VIRUS |  |  |  |   |
|  Adenovirus | Type 1, ATCC VR-1 | 061704J | - | 725  |
|  Adenovirus | Type 3, ATCC VR-3 | 112701A | - | 725  |
|  Adenovirus | Type 6, ATCC VR-1083 | 102904 | - | 725  |
|  Adenovirus | Type 7, ATCC VR-7 | 112701C | - | 725  |
|  Adenovirus | Type 8, ATCC VR-1368 | 111201D | - | 725  |
|  Adenovirus | Type 10, ATCC VR-1087 | 112701D | - | 725  |
|  Adenovirus | Type 13, ATCC VR-14 | 112701E | - | 725  |
|  Adenovirus | Type 14, ATCC VR-15 | 033104 | - | 725  |
|  Adenovirus | Type 18, ATCC VR-19 | 011702B | - | 725  |
|  Adenovirus | Type 31, ATCC VR-1109 | 011702 | - | 725  |
|  Adenovirus | Type 40, ATCC VR-931 | 012802A | - | 725  |
|  Adenovirus | Type 41, ATCC VR-930 | 012802 | - | 725  |
|  Influenza A | Aichi, ATCC VR-547 | 022604A | - | 2.1e3  |
|  Influenza A | Malaya, ATCC VR-98 | 022604M | - | 2.1e3  |
|  Influenza A | Hong Kong, ATCC VR-544 | 040104 | - | 2.1e3  |
|  Influenza A | Denver, ATCC VR-546 | 022604D | - | 2.1e3  |
|  Influenza A | Port Chalmers, ATCC VR-810 | 040104 | - | 2.1e3  |
|  Influenza A | PR, ATCC VR-1469 | 022604P | - | 2.1e3  |
|  Influenza A | Victoria, ATCC VR-822 | 042105 | - | 2.1e3  |
|  Influenza B | Hong Kong, ATCC VR-823 | 091704 | - | 2.1e3  |
|  Influenza B | Maryland, ATCC VR-296 | 091704 | - | 2.1e3  |
|  Influenza B | Mass, ATCC VR-523 | 061704 | - | 2.1e3  |
|  Influenza B | Taiwan, ATCC VR-295 | 061704E | - | 2.1e3  |
|  Influenza B | GL, ATCC VR-103 | 061704F | - | 2.1e3  |
|  Influenza B | Russia, ATCC VR-790 | 091704 | - | 2.1e3  |
|  RSV | Long, ATCC VR-26 | 042204L | - | 2.1e3  |
|  RSV | Wash, ATCC VR-1401 | 061704G | - | 2.1e3  |
|  RSV | 9320, ATCC VR-955 | 061704I | - | 2.1e3  |
|  Parainfluenza 1 | C-35, ATCC VR-94 | 020105 | - | Control Slide*  |
|  Parainfluenza 2 | Greer, ATCC VR-92 | 020105 | - | Control Slide*  |
|  Parainfluenza 3 | C 243, ATCC VR-93 | 020105 | - | Control Slide*  |
|  HSV-1 | 1F, ATCC VR-733 | 092704 | - | 150  |
|  HSV-1 | MacIntyre, ATCC VR-539 | 092804A | - | 150  |

*Virus was isolated from the same strain as the previous strain.

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Table 4 Bacteria, Yeast, and Protozoa Cross Reactivity Testing

|  Organism | Strain or Type | Lot Number | Chlamydiae DFA Reagent | TCID50 or CFU  |
| --- | --- | --- | --- | --- |
|  Bacteria | Acholeplasma laidlawi | 031404 | - | ~1.0e7  |
|  Bacteria | Acinetobacter calcoaceticus | 934332 | - | 9.7e5  |
|  Bacteria | Bordetella bronchiseptica | 031404 | - | 1.8e5  |
|  Bacteria | Bordetella pertussis | 031404 | - | 4.7e6  |
|  Bacteria | Chlamydiophila pneumoniae | CP-0176 | + | Control Slide*  |
|  Bacteria | Chlamydiophila psittaci | FP-12-050218 | + | Control Slide*  |
|  Bacteria | Chlamydia trachomatis | 052705 | + | Control Slide*  |
|  Bacteria | Corynebacterium diphtheriae | 031404 | - | 2.5e6  |

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|  Bacteria | Escherichia coli | 335472 | - | 2.6e5  |
| --- | --- | --- | --- | --- |
|  Bacteria | Gardnerella vaginalis | 3457511 | - | 5.0e5  |
|  Bacteria | Haemophilis influenzae type A | 031404 | - | 9.3e5  |
|  Bacteria | Klebsiella pneumoniae | 031404 | - | 6.4e6  |
|  Bacteria | Legionella pneumophila | 031404 | - | 6.5e4  |
|  Bacteria | Moraxella cartarrhalis | 031404 | - | 6.4e4  |
|  Bacteria | Mycoplasma hominis | 031404 | - | ~1.0e4  |
|  Bacteria | Mycoplasma orale | 031404 | - | ~1.0e4  |
|  Bacteria | Mycoplasma pneumoniae | 031404 | - | ~1.0e4  |
|  Bacteria | Mycoplasma salivarium | 031404 | - | ~1.0e7  |
|  Bacteria | Neisseria gonorrhoeae | 060805 | - | 1.3e6  |
|  Bacteria | Proteus mirabilis | 440498 | - | 2.1e6  |
|  Bacteria | Pseudomonas aeruginosa | 031404 | - | 1.0e7  |
|  Bacteria | Salmonella enteriditis | 3457511 | - | 2.5e6  |
|  Bacteria | Salmonella typhimurium | 363162 | - | 1.8e6  |
|  Bacteria | Staphylococcus aureus | 081100 | + | 1.0e7  |
|  Bacteria | Streptococcus agalactiae | 370784 | - | 9.6e6  |
|  Bacteria | Streptococcus pneumoniae | 031404 | - | 8.0e5  |
|  Bacteria | Streptococcus pyogenes | 031404 | - | 2.9e7  |
|  Bacteria | Ureaplasma urealyticum | 031404 | - | ~1.0e4  |
|  Yeast | Candida glabrata | 992206 | - | 8.7e6  |
|  Protozoa | Trichomonas vaginalis | 410721 | - |   |

f. Assay cut-off: Not applicable

2. Comparison studies:

a. Method comparison with predicate device:

This study included nine hundred and ninety four (994) original specimens evaluated for the presence of Chlamydiae by this product ("Subject" test) and three currently marketed Culture Confirmation Kits ("Comparison" tests). These evaluations were conducted at three external laboratory sites using one Comparison Device (American Microscan DFA Chlamydia Detection Kit) and one in-house laboratory where the two other Comparison Devices were used: (1) A reference laboratory in the southeastern United States; (2) A hospital laboratory in the mid-west United States; (3) A hospital laboratory in the southwestern United States; and (4) Diagnostic Hybrids' in-house virology laboratory.

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Table 5 A Summary of the Specimens by Site.

|   | Fresh prospective | Frozen prospective | Archived (frozen) | Site Total  |
| --- | --- | --- | --- | --- |
|  1 - FL | 156 | 240 |  | 396  |
|  2 - MO | 90 | 84 | 26 | 200  |
|  3 - TX | 23 | 68 | 187 | 278  |
|  4 - OH | 0 | 120 |  | 120  |

b. Matrix comparison: Not applicable

3. Clinical studies:

A subset of 661 prospectively collected and contiguous specimens, from study sites 1, 2, and 3, were tested using the same predicate device as comparator. Percent Agreement and 95% Confidence Interval between the Subject Device and Comparison test for the three external laboratory sites was calculated and is presented in Table 6. Results from both fresh and frozen specimens are included. PPA = positive percent agreement, NPA = negative percent agreement.

Table 6 Device Performance with Prospective Specimens

|  Combined Prospective Specimens |   |   | Fresh Prospective |   |   | Frozen Prospective  |   |   |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
|   | Comparison Device |   | Comparison Device |   |   | Comparison Device  |   |   |
|   | + | - | + | - |  | + | - |   |
|  + | 42 | 4 | + | 11 | 0 | + | 21 | 4  |
|  - | 2 | 613 | - | 0 | 258 | - | 2 | 355  |
|  PPA | 95.5% |  | 100% |  |  | 97.0% |  |   |
|  95% CI - PPA | 84.5% - 99.4% |  | 71.5% - 100% |  |  | 72.0% - 98.9% |  |   |
|  NPA | 99.4% |  | 100% |  |  | 98.9% |  |   |
|  95% CI - NPA | 98.3% - 99.8% |  | 98.6% - 100% |  |  | 97.2%-99.7% |  |   |

Results from the remaining specimens were not included in these calculations and are presented separately in section c below since (1) Sites 2 and 3 included a total of 213 specimens which had been frozen and archived in order to show performance of the Subject Device on a larger number of Chlamydiae-positive specimens, and (2) Site 4 tested the Subject Device against two Comparison Devices using 120 frozen specimens (prospectively collected, and contiguous).

a. Clinical Sensitivity: Not applicable
b. Clinical specificity: Not applicable
c. Other clinical supportive data (when a. and b. are not applicable):

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Due to low prevalence of Chlamydiae in the populations of specimens, investigators evaluated additional archived (frozen) specimens that had originally been identified as containing Chlamydiae. The combined results of testing of archived specimens at Sites 2 and 3 are presented in Table 7 below.

Table 7 Device Performance with Archival Specimens
Percent Agreement, Archival Specimens

|  Subject Device | Comparison Device  |   |   |
| --- | --- | --- | --- |
|   |   | + | -  |
|   |  + | 159 | 0  |
|   | - | 0 | 54  |

PPA 100%
95% CI - PPA 97.3-100%
NPA 100%
95% CI - NPA 93.3-100%

Site 4 Study: A total of 120 frozen specimens were tested for the presence of Chlamydiae against two different comparison devices:

Comparison Device PathoDx results Compared to those of Diagnostic Hybrids' D³ DFA Chlamydiae Device are presented in Table 8A

Table 8A Device Performance Compared to PathoDx

|  Subject Device
Diagnostic
Hybrids | Frozen  |   |   |
| --- | --- | --- | --- |
|   |   | + | -  |
|   |  + | 24 | 0  |
|   | - | 0 | 96  |

PPA 100%
95% CI - PPA 85.8% - 100%
NPA 100%
95% CI - NPA 96.2% - 100%

Comparison Device Pathfinder results Compared to those of Diagnostic Hybrids' D³ DFA Chlamydiae Device are presented in Table 8B

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Table 8 B Device Performance Compared to Pathfinder
Frozen
Comparison Device

|  Subject Device Diagnostic Hybrids | + | -  |
| --- | --- | --- |
|   |  23 | 1  |
|   |  0 | 96  |
|  PPA | 100% |   |
|  95% CI - PPA | 85.2% - 100%  |   |
|  NPA | 99.0%  |   |
|  95% CI - NPA | 94.4% - 100%  |   |

4. Clinical cut-off: Not applicable
5. Expected values/Reference range:

Clinical studies included patient specimens from a reference laboratory in the Southeastern United States, and hospital laboratories in Midwestern and Southwestern United States. Patient demographics for the specimens tested are presented below (Table 9A).

Table 9A Clinical Study Specimens: Patient Age and Gender

|  Values are # pos / Total | Site 1 |   | Site 2 |   | Site 3 |   | Site 4  |   |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  Age | F | M | F | M | F | M | F | M  |
|  TOTALS | 362 | 32 | 170 | 30 | 215 | 63 | 98 | 22  |
|  |   |   |   |   |   |   |   |   |
|  <1m | 0/1 | 0/3 | 0/2 | 2/4 | 9/15 | 14/19 | 0 | 0  |
|  1m to 2y | 0 | 0 | 0/4 | 0/2 | 4/28 | 11/22 | 0 | 0  |
|  2y to12y | 0/2 | 0 | 1/28 | 1/13 | 6/13 | 0 | 0 | 0  |
|  12y to18y | 0/17 | 0 | 31/117 | 5/10 | 79/143 | 14/20 | 0/7 | 0  |
|  18y to 21y | 6/56 | 1/4 | 4/19 | 1/1 | 4/13 | 0/2 | 9/30 | 3/7  |
|  >21y | 9/283 | 3/25 | 0 | 0 | 0/3 | 0 | 8/61 | 4/15  |
|  Age not reported | 1/3 | 0 | 0 | 0 | 0 | 0 | 0 | 0  |
|  Age/gender not reported | 0/2 |   | 0 |   | 0 |   | 0  |   |

The clinical studies were comprised of specimens collected and cultured for the presence of Chlamydiae. The specimen sources are described in Table 9B below.

{11}

Table 9B Clinical Study Specimens: Specimen Types

|  Site | Total | Not Indicated | Genital | penis | vaginal | cervical | rectal | perineum* | eye | urethral | mouth** | respiratory† | Aspirate  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  1 | 396 | 9 | 155 | 5 | 35 | 177 |  | 2 | 5 | 6 | 1 | 1 |   |
|  2 | 200 |  |  | 13 | 55 | 83 | 34 |  | 6 | 3 | 2 | 4 |   |
|  3 | 278 |  |  | 13 | 146 | 32 | 5 | 2 | 64 | 7 | 2 | 6 | 1  |
|  4 | 120 |  | 120 |  |  |  |  |  |  |  |  |  |   |
|  *perineum: groin, pubic, perianal, pelvic, endocervix **mouth: mouth, throat †respiratory: nasopharyngeal, nasal aspirate, tracheal aspirate, sputum  |   |   |   |   |   |   |   |   |   |   |   |   |   |

# N. Proposed Labeling:

The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.

# O. Conclusion:

1. The submitted information in this premarket notification is complete and supports a substantial equivalence decision.

---

**Source:** [https://fda.innolitics.com/submissions/MI/subpart-d%E2%80%94serological-reagents/LJP/K063675](https://fda.innolitics.com/submissions/MI/subpart-d%E2%80%94serological-reagents/LJP/K063675)

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