K Number

Device Name

ZEUS SCIENTIFIC, INC. TREPONEMA PALLIDUM IGG TEST SYSTEM

Manufacturer

ZEUS SCIENTIFIC, INC.

Date Cleared

2011-02-10

(182 days)

Product Code

LIP

Regulation Number

866.3830

Intended Use

The ZEUS ELISA Treponema pallidum IgG Test System is intended for the qualitative detection of specific IgG class antibodies to T. pallidum in human serum. The test may be used in conjunction with non treponemal testing and clinical findings to provide serological evidence of infection with T. pallidum. This test is for in vitro diagnostic use only. This test is not intended for screening blood or plasma donors.

Device Description

The ZEUS ELISA Treponema pallidum IgG Test System is designed to detect IgG class antibodies in human sera to Treponema pallidum. Wells of plastic microwell strips are sensitized by passive absorption with T. pallidum antigen. The test procedure involves three incubation steps: 1. Test sera are diluted with SAVE Diluent. During sample incubation, any antigen specific lgG antibody in the sample will bind to the immobilized antigen. The plate is washed to remove unbound antibody and other serum components. 2. Peroxidase conjugated goat anti-human IgG is added to the wells and the plate is incubated. The conjugate will react with IgG antibody immobilized on the solid phase in step 1. The wells are washed to remove unbound conjugate. 3. The microwells containing immobilized peroxidase conjugate with peroxidase substrate solution. Hydrolysis of the substrate by peroxidase produces a color change. After ten minutes have elapsed, the reaction is stopped and the color intensity of the solution is measured photometrically. The color intensity of the solution depends on upon the antibody concentration in the original test sample.

More Information

Contact

Type

Center

Panel

Date Received

Product Code

Subsequent Product Codes

Applicant Name (Manufacturer)

Device Name

Decision

Street 1

Street 2

City

State

Country Code

ZIP

Postal Code

Class Advise Committee

SSP Indicator

Third Party Reviewed

Expedited Review

Predicate Devices

Not Found

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The description details a standard ELISA assay with photometric measurement and does not mention any AI/ML components for data analysis or interpretation.

Therapeutic

No.
This device is an in vitro diagnostic test for detecting antibodies, not a treatment or therapy.

Diagnostic

Yes

The device is intended for the qualitative detection of specific IgG class antibodies to T. pallidum in human serum, used in conjunction with non-treponemal testing and clinical findings to provide serological evidence of infection with T. pallidum. This directly indicates its use in diagnosing a medical condition.

SaMD (Software as a Medical Device)

The device description clearly outlines a laboratory-based ELISA test system involving physical components like microwell strips, reagents, and photometric measurement, indicating it is a hardware-based in vitro diagnostic device, not software-only.

IVD (In Vitro Diagnostic)

Yes, this device is an IVD (In Vitro Diagnostic).

Here's why:

Intended Use Statement: The "Intended Use / Indications for Use" section explicitly states: "This test is for in vitro diagnostic use only." This is a clear declaration of its intended purpose.
Device Description: The description details a laboratory procedure involving human serum samples and chemical reactions (ELISA) to detect antibodies. This is characteristic of an in vitro diagnostic test.
Clinical Performance Studies: The document describes clinical studies where the device was used to test human serum samples and the results were compared to a reference assay (TPPA) and clinical diagnoses. This is a standard part of the validation process for IVD devices.
Intended User / Care Setting: The intended user is described as a "hospital laboratory" and the use is "in vitro diagnostic use; prescription use only." This further confirms its classification as an IVD.

The entire document describes a product designed to be used outside of the body (in vitro) to diagnose a condition (syphilis) by analyzing a biological sample (human serum). This aligns perfectly with the definition of an In Vitro Diagnostic device.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The ZEUS EUSA Treponema pallidum IgG Test System is intended for the qualitative detection of specific IgG class antibodies to T. pallidum in human serum. The test may be used in conjunction with non treponemal testing and clinical findings to provide serological evidence of infection with T. pallidum. This test is for in vitro diagnostic use only.

This test is not intended for screening blood or plasma donors.

Indications for Use: This test system when used in conjunction with non-treponemal based assays provides serological evidence of infection with Treponema pallidum.

Product codes (comma separated list FDA assigned to the subject device)

LIP

Device Description

1. Test sera are diluted with SAVE Diluent. During sample incubation, any antigen specific lgG antibody in the sample will bind to the immobilized antigen. The plate is washed to remove unbound antibody and other serum components.
1. Peroxidase conjugated goat anti-human IgG is added to the wells and the plate is incubated. The conjugate will react with IgG antibody immobilized on the solid phase in step 1. The wells are washed to remove unbound conjugate.
1. The microwells containing immobilized peroxidase conjugate with peroxidase substrate solution. Hydrolysis of the substrate by peroxidase produces a color change. After ten minutes have elapsed, the reaction is stopped and the color intensity of the solution is measured photometrically. The color intensity of the solution depends on upon the antibody concentration in the original test sample.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Not Found

Indicated Patient Age Range

The 500 prospectively collected samples from patients ranging in age from 70 years of age.
The 500 samples collected from pregnant women ranging in age from 15 to 48.
The 1000 samples from unselected hospitalized patients ranging in age from 70.

Intended User / Care Setting

Not Found

Description of the training set, sample size, data source, and annotation protocol

Not Found

Description of the test set, sample size, data source, and annotation protocol

Clinical Data Generated for Submission: Method Comparison with Predicate Device

1. Prospectively Collected Intended Use Populations:
- . 500 unselected samples from patients with a syphilis test ordered. The samples were submitted for syphilis antibody testing, sequentially numbered, de-identified and archived.
- . 500 unselected samples from pregnant women with a syphilis test ordered. The samples were submitted for syphilis antibody testing, sequentially numbered, de-identified and archived.

After procurement, the samples were tested at a hospital laboratory located in the Mid-Atlantic, the Northeast and at Zeus. The hospital laboratories tested 200 samples from patients with a syphilis test ordered and 200 samples from pregnant women. Zeus tested 100 samples from patients with a syphilis tests ordered and 100 samples from pregnant women.

1. Prospectively Collected Population of Unselected Hospitalized Patients: Additional clinical performance was assessed in a population of 1000 hospitalized patients. These samples were pulled from a hospital laboratory routine workload of patient testing.
1. Prospective HIV-1 Positive Samples: 223 banked known positive HIV-1 samples were acquired from a New York vendor.
Retrospective TPPA /RPR Positive: 280 samples requested to be RPR/TPPA positive were 4. purchased from a New York vendor.
1. Retrospective TPPA Negative Collected from Pregnant Women: 250 samples requested to be collected from pregnant women and requested to be syphilis antibody negative were purchased from a New York vendor.
Retrospective TPPA Positive Collected from Pregnant Women: 27 samples requested to be 6. collected from pregnant women and requested to be RPR/TPPA positive were purchased from a New York vendor.
1. CDC Syphilis Panel: 157 samples of various reactivity to syphilis were evaluated.

All serum samples evaluated for concordance were tested with the treponemal (TPPA) reference assay. Samples that were positive by TPPA were reference assay positive. Samples that were negative by TPPA were reference assay negative.

Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)

Study Type: Clinical Performance and Comparative Testing for Intended Use Populations in a Prospective Study, Precision and Reproducibility studies.
Sample Sizes:

Clinical Performance: A total of 2,937 serum samples (500 from patients with a syphilis test ordered, 500 from pregnant women, 1000 from unselected hospitalized patients, 223 HIV-1 positive, 280 RPR/TPPA positive, 250 TPPA negative from pregnant women, 27 TPPA positive from pregnant women, and 157 CDC Syphilis Panel).
Precision: 15 samples (Negative, High Negative, Near Cut-off, Low Positive, High Positive). Each tested 48 times (two dilutions, two runs per day, over twelve days).
Reproducibility: 15 samples (Negative, High Negative, Near Cut-off, Low Positive, High Positive). Each tested 180 times (two dilutions, triplicate runs, two technologists, over five days at three sites).

Key Results:

Clinical Performance (Concordance with TPPA reference assay):

Prospectively Collected Intended Use Populations (Patients with syphilis test ordered, n=500):
- PPA (Positive Percent Agreement): 80.0% (95% CI: 28.4-99.5%) based on 5 predicate positives.
- NPA (Negative Percent Agreement): 99.2% (95% CI: 97.9-99.8%) based on 495 predicate negatives.
Banked purchased sera from pregnant women with syphilis test ordered (n=498):
- PPA: 75.0% (95% CI: 19.4-99.4%) based on 4 predicate positives.
- NPA: 100.0% (95% CI: 99.4-100%) based on 494 predicate negatives.
Unselected hospitalized patients (n=1000):
- PPA: 61.9% (95% CI: 38.4-81.9%) based on 21 predicate positives.
- NPA: 97.1% (95% CI: 95.9-98.1%) based on 978 predicate negatives.
Banked purchased known HIV-1 positive serum samples (n=223):
- PPA: 85.4% (95% CI: 72.2-93.9%) based on 46 predicate positives.
- NPA: 99.4% (95% CI: 96.9-100%) based on 175 predicate negatives.
Banked purchased sera requested to be RPR/TPPA reactive (n=280):
- PPA: 98.5% (95% CI: 96.2-99.6%) based on 263 predicate positives.
- NPA: 70.6% (95% CI: 46.9-98.7%) based on 16 predicate negatives.
Banked purchased sera from pregnant women requested to be TPPA positive (n=27)/RPR/TPPA non-reactive (n=250):
- PPA: 92.9% (95% CI: 76.5-99.1%) based on 28 predicate positives.
- NPA: 99.6% (95% CI: 97.8-100%) based on 248 predicate negatives.
CDC Syphilis Panel (n=157) - Agreement with Clinical Diagnosis:
- Primary Treated: 100% (11/11)
- Secondary Untreated: 95.3% (41/43)
- Secondary Treated: 100% (39/39)
- Latent Untreated: 54.5% (6/11)
- Latent Treated: 96.0% (48/50)
- Congenital: 33.3% (1/3)
- Total: 93.0% (146/157) (95% CI: 87.8-96.5%)

Precision (In-House Repeatability):

Total CV for reactive samples: 20% signal change with high/low albumin, hemoglobin, intralipid, bilirubin, cholesterol, and triglycerides, but qualitative result remained negative.

Cross Reactivity:

No positive results were observed for any of the tested analytes (EBV, ANA, RF IgM, Rubella, HIV, HSV 1, HSV 2, Sera from Pregnant Patients, Hepatitis B, VZV, VZV IgM, CMV, Toxoplasma, Lyme G/M, Hepatitis C).

Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)

Positive Percent Agreement (PPA)
Negative Percent Agreement (NPA)
Percent Agreement with Clinical Diagnosis

Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.

Pheonix Bio-Tech Trep-Chek (This device is mentioned as a comparison device, but no K number is explicitly listed for it in the provided text. The text only states "substantially equivalent to a commercially marketed test system which has been previously cleared by the FDA for in vitro diagnostic use.")

Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).

Not Found

Regulation Number and Section

§ 866.3830

Treponema pallidum treponemal test reagents.(a)
Identification. Treponema pallidum treponemal test reagents are devices that consist of the antigens, antisera and all control reagents (standardized reagents with which test results are compared) which are derived from treponemal sources and that are used in the fluorescent treponemal antibody absorption test (FTA-ABS), theTreponema pallidum immobilization test (T.P.I.), and other treponemal tests used to identify antibodies toTreponema pallidum directly from infecting treponemal organisms in serum. The identification aids in the diagnosis of syphilis caused by bacteria belonging to the genusTreponema and provides epidemiological information on syphilis.(b)
Classification. Class II (performance standards).

Summary

Zeus Scientific Inc. 510(k) Summary ZEUS ELISA Treponema pallidum IgG FEB 1 0 2011 Test System K102283

Zeus Scientific, Inc. (Zeus) PO Box 38, Raritan, NJ 08869 (908)526-3744 Contact: Ewa Nadolczak, Manager of Clinical Affairs, Direct (609) 408-1331 enadolczak@zeusscientific.com

Measurand: Treponema pallidum IgG antibodies. Type of Test: ELISA. Proprietary Name: ZEUS ELISA Treponema pallidum IgG Test System.

Section 1: Regulatory Information

Device Classification: Enzyme Linked Immunoabsorbent Assay, Treponema pallidum 1.
1. Regulation Description: Treponema pallidum treponemal test reagents
1. Class: 2
1. Product Code: LIP
1. Panel: Microbiology
Regulation Number: 866.3830 ହ.

Section 2: Intended Use

The ZEUS EUSA Treponema pallidum IgG Test System is intended for the qualitative detection of specific IgG class antibodies to T. pollidum in human serum. The test may be used in conjunction with non treponemal testing and clinical findings to provide serological evidence of infection with T. pallidum. This test is for in vitro diagnostic use only.

This test is not intended for screening blood or plasma donors.

Section 3: Indications for Use

Indications for Use: This test system when used in conjunction with non-treponemal based assays provides serological evidence of infection with Treponema pallidum.

Special Conditions for Use Statements:

This test is for in vitro diagnostic use only. · This test is for prescription use only. This test is not intended for screening blood or plasma donors.

Section 4: Substantial Equivalence

Examination of enclosed data indicates that the ZEUS ELISA Treponema pallidum IgG Test System for the qualitative detection of specific human IgG class antibodies to treponema pallidum in human serum is substantially equivalent to a commercially marketed test system which has been previously cleared by the FDA for in vitro diagnostic use.

T. pallidum IgG Result Interpretation:
OD Value	Result	Interpretation
≤ 0.90	Negative	A result of ≤0.90 indicates no detectable IgG antibodies to T. pallidum and should be reported
as non-reactive for IgG antibody to T. pallidum.
0.91 - 1.1	Equivocal	Specimens with results in the equivocal range (0.91 - 1.1) should be retested in duplicate. Any
two of the three results which agree should be reported. Specimens that remain equivocal
after repeat testing may be tested by an alternate serologic procedure and/or re-evaluated by
drawing another sample one to three weeks later.
>1.1	Positive	A result of > 1.1 indicates that the specimen is positive for IgG antibody to T. pallidum, the
causative agent for syphilis.
		A positive test result presumes a current or past infection with T. pallidum, and should be
reported as reactive for IgG antibody to T. pallidum. Other T. pallidum serology assays should
be performed to confirm or rule out a current case of active syphilis.

Section 5: Interpretation of Results

Section 5A: Comparison of Investigational Device to Predicate Device

The comparisons of the ZEUS ELISA T.pallidum IgG Test System to the predicate device follow, including intended use and various aspects of the procedure.

Characteristic	ZEUS ELISA T.pallidum IgG	Pheonix Bio-Tech Trep-Chek
Use
Intended Use	For in vitro diagnostic use only
Intended Use: The ZEUS ELISA Treponema
pallidum ELISA Test System is intended for
the qualitative detection of specific IgG class
antibodies to T. pallidum in human serum.
The test system is intended to be used as an
aid in the laboratory diagnosis of Syphilis
disease caused by T. pallidum spirochete.	For in vitro diagnostic use only
The Phoenix Bio-Tech Corp. Syphilis Trep-
Chek Test Kit is a confirmatory immunoassay
for the qualitative detection of Treponema
pallidum IgG antibodies in human serum.
Assay
Detection Method
Solid Phase
Antigen Used	Immunoassay
Colormetric
Polystyrene 96 well plate
recombinant p 17 Treponema pallidum
antigen	Immunoassay
Colormetric
Polystyrene 96 well plate
Recombinant Treponema pallidum antigen
Specimen Tested	Human Serum	Human Serum
Controls	One Positive Control, one Negative Control	One Positive Control, one Negative Control
Calibration	Includes Calibrator (human serum)	Includes Calibrator (human serum)
Analyte Measured
Sample Dilution	Human IgG
1:21 in SAVe Diluent	Human IgG
1:20 in phosphate buffer based diluent
Sample Incubation	25 +/- 5 minutes at room temperature	30 +/- 2 minutes at room temperature
Post Sample Wash	5x wash (dispense/aspirate)	4x wash (dispense/aspirate)
Conjugate	Goat anti-human IgG; Fc chain specific	Goat anti-human IgG; y chain specific
Conjugate Label	Horse radish peroxidase	Horse radish peroxidase
Conjugate Incubation	25 +/- 5 minutes at room temperature	30 +/- 2 minutes at room temperature
Post Conjugate Wash	5x wash (dispense/aspirate)	4x wash (dispense/aspirate)
Substrate	TMB	TMB
Reading
Data Points	Read the color change (optical density) of
the wells
Read one OD value for each control and
sample	Read the color change (optical density) of
the wells
Read one OD value for each control and
sample
Math	Single point curve	Single point curve
Scale	Calculate the index value of unknown
samples by comparing their OD to the cut
off OD	Calculate the index value of unknown
samples by comparing their OD to the cut
off OD
Interpretation Criteria	Negative is = 1.10 and
Equivocal is 0.90 - 1.09	Negative is = 1.10 and
Equivocal is 0.90 - 1.09

Section 6: Test Principle

1. Test sera are diluted with SAVE Diluent. During sample incubation, any antigen specific lgG antibody in the sample will bind to the immobilized antigen. The plate is washed to remove unbound antibody and other serum components.
1. Peroxidase conjugated goat anti-human IgG is added to the wells and the plate is incubated. The conjugate will react with IgG antibody immobilized on the solid phase in step 1. The wells are washed to remove unbound conjugate.
1. The microwells containing immobilized peroxidase conjugate with peroxidase substrate solution. Hydrolysis of the substrate by peroxidase produces a color change. After ten minutes have elapsed, the reaction is stopped and the color intensity of the solution is measured photometrically. The color intensity of the solution depends on upon the antibody concentration in the original test sample.

Section 7: Linearity

The WHO International Standard was diluted serially. Each dilution was tested in duplicate, the mean calculated and the result plotted.

Image /page/3/Figure/7 description: The image is a graph titled "T.pallidum IgG Linearity". The x-axis is labeled "Numerical Interpretation of Dilution Factor" and ranges from 0 to 0.6. The y-axis is labeled "Mean Index Value" and ranges from 0.00 to 3.50. The graph shows a linear relationship with an R-squared value of 0.9971.

Section 8: Analytical Specificity

Interfering Substances

The effect of potential interfering substances on sample results generated using the test system was evaluated with the following possible interfering substances: albumin, bilirubin, cholesterol, hemoglobin, triglycerides and intralipids.

The quantity of analyte in each interfering substance is as follows:

Bilirubin: 1mg/dL (low), 15 mg/dL (high) Albumin: 3.5 g/dL (low), 5 g/dL (high) Cholesterol: 150 mg/dL (low), 250 mg/dL (high) Triglycerides: 150 mg/dL (low), 500 mg/dL (high) Hemoglobin: 20 g/dL (low), 20 g/dL (high) Intralipid: 300 mg/dL (low), 750 mg/dL (high)

Three samples for Treponema pallidum IgG were chosen based on their performance on the Treponema pallidum IgG ELISA test system: positive, borderline and negative. The samples were exposed to the possible interfering substances and tested. An increase or reduction of signal equal to or less than 20% is considered acceptable. The negative sample may have a signal change greater than 20% if there is no change in the qualitative result of the sample. All signal changes greater than 20 % must be specified in the package insert.

All positive samples showed less than a 20% recovery of signal.

The borderline samples showed a recovery of signal 20%) with the high and low spikes of albumin, hemoglobin, intralipid, bilirubin, cholesterol and triglycerides. The negative sample results in each instance stayed below the cut-off and the change in signal did not affect the qualitative result.

Cross Reactivity

Ten samples minimally for each cross-reactant were tested. The results presented were obtained by testing the analytes against high concentrations of possible cross reactants. The results of this study are summarized in the following table.

| Treponema pallidum IgG

Cross reactivity Study
Analyte	positive/tested
EBV	0/10
ANA	0/10
RF IgM	0/10
Rubella	0/10
HIV	0/10
HSV 1	0/10
HSV 2	0/10
Sera from Pregnant Patients	0/10
Hepatitis B	0/10
VZV	0/10
VZV IgM	0/10
CMV	0/10
Toxoplasma	0/10
Lyme G/M	0/10
Hepatitis C	0/10

Detection Limits

This is a qualitative assay (Positive, Negative or Equivocal results) so there is no limit of detection study.

Section 9: Clinical Performance

Clinical Data Generated for Submission: Method Comparison with Predicate Device

1. Prospectively Collected Intended Use Populations:
- . 500 unselected samples from patients with a syphilis test ordered. The samples were submitted for syphilis antibody testing, sequentially numbered, de-identified and archived.
- . 500 unselected samples from pregnant women with a syphilis test ordered. The samples were submitted for syphilis antibody testing, sequentially numbered, de-identified and archived.

1. Prospectively Collected Population of Unselected Hospitalized Patients: Additional clinical performance was assessed in a population of 1000 hospitalized patients. These samples were pulled from a hospital laboratory routine workload of patient testing.
1. Prospective HIV-1 Positive Samples: 223 banked known positive HIV-1 samples were acquired from a New York vendor.
Retrospective TPPA /RPR Positive: 280 samples requested to be RPR/TPPA positive were 4. purchased from a New York vendor.
1. Retrospective TPPA Negative Collected from Pregnant Women: 250 samples requested to be collected from pregnant women and requested to be syphilis antibody negative were purchased from a New York vendor.
Retrospective TPPA Positive Collected from Pregnant Women: 27 samples requested to be 6. collected from pregnant women and requested to be RPR/TPPA positive were purchased from a New York vendor.
1. CDC Syphilis Panel: 157 samples of various reactivity to syphilis were evaluated.

1. Precision and Reproducibility: Precision of the device was assessed using fifteen samples. These repeatability studies were performed internally at the manufacturing site's laboratory. Reproducibility was assessed using fifteen samples tested at two external sites and internally at Zeus.

Prevalence and Expected Values

To determine expected values in the populations tested, internal investigators assessed the device's performance with 500 masked samples prospectively collected from individuals and 500 samples from pregnant women. The samples were requested to be random, unselected sera submitted for syphilis antibody testing. Additional studies were conducted in a population of 1000 unselected hospitalized patients.

In the 500 prospectively collected samples from patients ranging in age from 70 years of age, 7 tested positive. The overall observed prevalence in this group was 1.4% (7/500 samples).

In the 500 samples collected from pregnant women ranging in age from 15 to 48, 3/498 samples tested positive. The observed prevalence in this group was 0.6%. Two samples were excluded due to questionable age.

In the group of 1000 samples from unselected hospitalized patients ranging in age from 70 years of age, 32 tested positive. The overall observed prevalence in this group was 3.2% (32/999 samples). One sample was QNS for testing.

Clinical Performance and Comparative Testing for Intended Use Populations in a Prospective Study

The comparative study for the Intended Use Populations consisted of 500 unselected serum samples from patients with a syphilis test ordered. 500 purchased serum samples from pregnant women were also tested.

PERFORMANCE CHARACTERISTICS

The clinical study consisted of 2,937 serum samples evaluated at three sites located in the United States. All serum samples evaluated for concordance were tested with the treponemal (TPPA) reference assay. Samples that were positive by TPPA were reference assay positive. Samples that were negative by TPPA were reference assay negative. The testing sites, sample volumes are presented in the following table:


Prospective Samples				Rerospective Samples
patients with	pregnant	sera from	purchased	purchased	purchased	sera requested	CDC
syphilis test	women with	unselected	sera from	sera from	sera requested	to be	Syphilis
test	syphilis test	hospitalized	HIV positive	pregnant	to be		characterized

Sites	ordered	ordered	patients	patients	women	RPR/TPPA +	samples
Zeus	100	100	350	223	0	0	0
Monmouth	200	200	350	0	277	280	0
Mainline	200	200	300	0	0	0	0
CDC	0	0	0	0	0	0	157
Total	500	500	1000	223	277	280	157

Prospectively Collected Intended Use Populations:

500 unselected samples from patients with a syphilis test ordered. The samples were submitted for syphilis antibody testing, sequentially numbered, de-identified and archived.

		Banked sera from patients with syphilis test ordered
		Predicate
		Positive	Equivocal	Negative	Site Total	PPA/NPA	95% CI
T.pallidum IgG ELISA	Positive	4	0	3	7	80.0%	28.4-99.5%
	Equivocal	1	0	1	2
	Negative	0	0	491	491	99.2%	97.9-99.8%
	Site Total	5	0	495	500

500 unselected samples from pregnant women with a syphilis test ordered. The samples were submitted for syphilis antibody testing, sequentially numbered, de-identified and archived.

Banked purchased sera from pregnant women with syphilis test ordered
Predicate
		Positive	Equivocal	Negative	Site Total	PPA
NPA	95% CI
T.pallidum IgG ELISA	Positive	3	0	0	3	75.0%	19.4-99.4%
	Equivocal	0	0	0	0
	Negative	1	0	494	495	100.0%	99.4-100%
	Site Total	4	0	494	498

*2 samples excluded due to unverifiable age

Prospectively Collected Population of Unselected Hospitalized Patients: Additional clinical performance was assessed in a population of 1000 hospitalized patients. These samples were pulled from a hospital laboratory routine workload of patient testing and were tested at the three clinical sites.

Image /page/7/Figure/8 description: The image shows a table with three rows. The first row contains the text "Unselected hospitalized patients". The second row contains the text "Predicate". The third row contains the text "PPA".

		Positive	Equivocal	Negative	Site Total	NPA	95% CI
T.pallidum IgG ELISA	Positive	13	1	18	32	61.9%	38.4-81.9%
	Equivocal	1	0	9	10
	Negative	7	0	950	957	97.1%	95.9-98.1%
	QNS	0	0	1	1
Site Total		21	1	978	1000

Retrospective HIV-1 Positive Samples: 223 banked known positive HIV-1 samples were acquired from a New York vendor.

		Banked purchased known HIV-1 positive serum samples
		Predicate
		Positive	Equivocal	Negative	Site Total	PPA
NPA	95% CI
T.pallidum IgG
ELISA	Positive	41	0	1	42	85.4%	72.2-93.9%
	Equivocal	1	0	0	1
	Negative	4	2	174	180	99.4%	96.9-100%
	Site Total	46	2	175	223

Retrospective TPPA /RPR Positive: 280 samples requested to be RPR/TPPA positive were purchased from a New York vendor.

	Banked purchased sera requested to be RPR/TPPA reactive
	Predicate
	Positive	Equivocal	Negative	Site Total	PPA
NPA	95% CI
T.pallidum IgG
ELISA	Positive	259	1	4	264	98.5%	96.2-99.6%
	Equivocal	1			1
	Negative	3		12	15	70.6%	46.9-98.7%
	Site Total	263	1	16	280

Retrospective TPPA Negative and TPPA Positive Samples Collected from Pregnant Women: 250 samples requested to be collected from pregnant women and requested to be syphilis antibody negative were purchased from a New York vendor. Only 27 samples requested to be collected from pregnant women and requested to be RPR/TPPA positive were available. These samples were purchased from a New York vendor.

Banked purchased sera from pregnant women requested to be TPPA positive (27)

		RPR/TPPA non-reactive (250)
		Predicate
		Positive	Equivocal	Negative	Site Total	PPA/NPA	95% CI
T.pallidum IgG ELISA	Positive	26	1	0	27	92.9%	76.5-99.1%
	Equivocal	0	0	0	0
	Negative	2	0	248	250	99.6%	97.8-100%
	Site Total	28	1	248	277

CDC Syphilis Panel: 157 samples from patients with various clinical diagnoses with syphills disease were evaluated. The % agreement of the Treponema pallidum IgG ELISA kit with the clinical diagnosis is presented in the following table.

| Clinical Diagnosis | T. pallidum IgG ELISA Results | | | | % Agreement with Clinical Diagnosis
Presented with 95% CI | |
|---------------------|-------------------------------|-----------|----------|-------|--------------------------------------------------------------|------------|
| | Positive | Equivocal | Negative | Total | | |
| Primary Treated | 11 | 0 | 0 | 11 | 100% (11/11) | 76.2-100% |
| Secondary Untreated | 41 | 0 | 2 | 43 | 95.3% (41/43) | 84.2-99.4% |
| Secondary Treated | 39 | 0 | 0 | 39 | 100% (39/39) | 92.6-100% |
| Latent Untreated | 6 | 0 | 5 | 11 | 54.5% (6/11) | 23.4-83.3% |
| Latent Treated | 48 | 0 | 2 | 50 | 96.0% (48/50) | 86.3-99.5% |
| Congenital | 1 | 1 | 1 | 3 | 33.3% (1/3) | 0.84-90.6% |
| Total | 146 | 1 | 10 | 157 | 93.0% (146/157) | 87.8-96.5% |

PRECISION and REPRODUCIBILITY

Precision

Precision was evaluated at the manufacturer site. The study was conducted as follows: fifteen samples were identified and/or prepared (by Zeus Scientific, Inc.) for use in the study based upon their activity on the ZEUS ELISA Treponema pallidum IgG assay. Three samples each were selected that were negative, high negative, near cut-off, low positive. On each day of testing, the samples were diluted twice and tested. This was repeated in a second run on the same day by a different technologist for a total of twelve days. Precision is considered acceptable for the reactive samples if the Total CV is