Predicate Devices

VIDAS TOXO IgM Test System (K923166)

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The device description details a standard immunoassay process and mentions results being determined automatically by the Elecsys software by comparing signals to a cutoff value, which is a typical automated analysis method, not indicative of AI/ML. There are no mentions of AI, ML, or related concepts in the provided text.

Therapeutic

No.
This device is an in vitro diagnostic immunoassay used for qualitative detection of antibodies, aiding in diagnosis. It does not provide any therapeutic intervention or treatment.

Diagnostic

Yes

The "Intended Use / Indications for Use" section states that the assay "may be used as an aid in the diagnosis of an acute or recent Toxoplasma gondii infection in suspected patients and pregnant women." This directly indicates its role in diagnosis.

SaMD (Software as a Medical Device)

No

The device description clearly details a physical immunoassay process involving reagents, microparticles, and electrochemiluminescence detection, which are hardware components. While software is mentioned for result determination, it is integral to a larger hardware-based system.

IVD (In Vitro Diagnostic)

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

Here's why:

Intended Use: The "Intended Use / Indications for Use" section explicitly states that the Elecsys Toxo IgM immunoassay is "for the in vitro qualitative detection of IgM antibodies to Toxoplasma gondii in human serum and plasma." The phrase "in vitro" is a key indicator of an IVD, meaning it's used to test samples outside of the body.
Purpose: The assay is used as an "aid in the diagnosis of an acute or recent Toxoplasma gondii infection," which is a diagnostic purpose.
Sample Type: It analyzes "human serum and plasma," which are biological samples.
Device Description: The description details a laboratory-based immunoassay process involving reagents, microparticles, and detection methods, all typical of IVD devices.
Quality Control: The mention of "PreciControl Toxo IgM is used for quality control" further supports its use in a clinical laboratory setting for diagnostic testing.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The Elecsys Toxo IgM immunoassay is for the in vitro qualitative detection of IgM antibodies to Toxoplasma gondii in human serum and plasma. This assay may be used as an aid in the diagnosis of an acute or recent Toxoplasma gondii infection in suspected patients and pregnant women. Patient testing must be performed in conjunction with an anti-Toxoplasma gondii IgG antibody assay.

The electrochemiluminescence immunoassay "ECLIA" is intended for use on Elecsys and cobas e immuno-assay analyzers. This assay has not been cleared by the FDA for blood/plasma donor screening.

PreciControl Toxo IgM is used for quality control of the Elecsys Toxo IgM immunoassay on the Elecsys and cobas e immunoassay analyzers.

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

LGD, JJX

Device Description

The Elecsys Toxo IgM is a two-step sandwich immunoassay with streptavidin microparticles and electrochemiluminescence detection. In the first incubation 10 uL of sample are automatically prediluted 1:20 with Elecsys Diluent Universal and T. gondii-specific recombinant antigen labeled with a ruthenium complex is added. Anti-Toxo IgM antibodies present in the sample react with the ruthenium-labeled T. gondii-specific recombinant antigen. Then biotinylated monoclonal human-IgM- specific antibodies and streptavidin-coated microparticles are added. The complex becomes bound to the solid phase via interaction of biotin and streptayidin. The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell. Application of a voltage to the electrode then induces chemiluminescent emission which is measured by a photomultiplier. Results are determined automatically by the Elecsys software by comparing the electrochemiluminescence signal obtained from the reaction product of the sample with the signal of the cutoff value previously obtained by Toxo IgM calibration.

The reagent working solutions include:

rackpack (kit placed on instrument)
- Streptavidin coated microparticles, -
- Reagent 1 (Toxoplasma-Ag~ Ru(bpy)2+3) and -
- Reagent 2 (Anti human IgM Ab~biotin). -
- Included with the kit: -
  - . Calibrator 1 (negative calibrator) Human serum non-reactive for anti Toxo IgM
  - . Calibrator 2 (positive calibrator) Human serum reactive for anti Toxo IgM

PreciControl Toxo IgM is a ready for use control serum based on human serum. The controls are used for monitoring the accuracy of the Elecsys Toxo IgM immunoassay.

The PreciControl Toxo IgM includes:

PC Toxo IgM 1 (Human serum negative for Toxo IgM antibodies, preservatives) .
PC Toxo IgM 2 (Human serum positive for Toxo IgM antibodies, preservatives) .

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 patient's age ranged from 2 to 86.

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

Not Found

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

Non-Clinical Performance Evaluation

Precision: Determined at one site using Elecsys reagents, human sera and controls, 6 times daily for 10 days (n = 60). Results showed repeatability, between-run, and intermediate precision with CVs ranging from 1.5% to 5.2%.
Reproducibility: Determined at two sites using Elecsys reagents and human sera, 6 times daily for 10 days at each site (n = 120). Results showed repeatability, between-run, intermediate precision, and between-site precision, with total precision CVs ranging from 4.9% to 13.6%.
Cross-reactivity: 218 potentially cross-reacting samples were tested. Most showed 0% cross-reactivity. Some notable cross-reactivity percentages were AMA (6.7%), EBV (10%), HBV (4.8%), Malaria (8%), and Rubella (10%).
Matrix equivalency study: Evaluated serum/gel separation tubes, lithium heparin plasma, K2-EDTA plasma, and sodium citrate plasma. A minimum of 49 sample pairs were drawn into serum and plasma collection tubes. All results met acceptance criteria.
Limitations - interference: The assay is unaffected by Bilirubin (

Regulation Number and Section

§ 866.3780

Toxoplasma gondii serological reagents.(a)
Identification. Toxoplasma gondii serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies toToxoplasma gondii in serum. Additionally, some of these reagents consist of antisera conjugated with a fluorescent dye (immunofluorescent reagents) used to identifyToxoplasma gondii from clinical specimens. The identification aids in the diagnosis of toxoplasmosis caused by the parasitic protozoanToxoplasma gondii and provides epidemiological information on this disease. Congenital toxoplasmosis is characterized by lesions of the central nervous system, which if undetected and untreated may lead to brain defects, blindness, and death of an unborn fetus. The disease is characterized in children by inflammation of the brain and spinal cord.(b)
Classification. Class II (performance standards).

Summary

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Image /page/0/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo features the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged in a circular fashion around a symbol. The symbol consists of three stylized human profiles facing to the right, with flowing lines connecting them. The logo is black and white.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

June 23, 2017

ROCHE DIAGNOSTICS KELLI TÜRNER REGULATORY AFFAIRS PRINCIPAL 9115 HAGUE RD. INDIANAPOLIS IN 46250

Re: K162678

Trade/Device Name: Elecsys Toxo IgM. Elecsys Toxo IgM PreciControl Regulation Number: 21 CFR 866.3780 Regulation Name: Toxoplasma gondii serological reagents Regulatory Class: II Product Code: LGD, JJX Dated: May 19, 2017 Received: May 22, 2017

Dear Ms. Turner:

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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 898. 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); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

1

If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours,

Ribhi Shawar -S For

Uwe Scherf, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K162678

Device Name Elecsys Toxo IgM Immunoassay

Indications for Use (Describe)

Elecsys Toxo IgM Immunoassay

The Elecsys Toxo IgM immunoassay is for the in vitro qualitative detection of IgM antibodies to Toxoplasma gondii in human serum and plasma. This assay may be used as an aid in the diagnosis of an acute or recent Toxoplasma gondii infection in suspected patients and pregnant women. Patient testing must be performed in conjunction with an anti-Toxoplasma gondii IgG antibody assay.

The electrochemiluminescence immunoassay "ECLIA" is intended for use on Elecsys and cobas e immuno-assay analyzers. This assay has not been cleared by the FDA for blood/plasma donor screening.

PreciControl Toxo IgM

PreciControl Toxo IgM is used for quality control of the Elecsys Toxo IgM immunoassay on the Elecsys and cobas e immunoassay analyzers.

Type of Use (Select one or both, as applicable)
-------------------------------------------------

X Prescription Use (Part 21 CFR 801 Subpart D)

Over-The-Counter Use (21 CFR 801 Subpart C)

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Elecsys Toxo IgM 510(k) Summary

This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of 21 CFR 807.92.

Submitter Name	Roche Diagnostics
Address	9115 Hague Road
Indianapolis, IN 46250
Contact	Kelli Turner
Phone: (317) 521-4515
FAX: (317) 521-3080
Email: kelli.turner@roche.com
Date Prepared	June 21, 2017
Proprietary Name	1) Elecsys Toxo IgM

PreciControl Toxo IgM |
| Common Name | 1) Toxo IgM
PreciControlToxo IgM |
| Classification Name | 1) Toxoplasma gondii serological reagents
Single (specified) analyte controls (assayed and unassayed) |
| Product Codes | 1) LGD, 866.3780
JJX, 862.1660 |
| Predicate Device | 1) VIDAS TOXO IgM Test System (K923166) |
| Establishment Registration | Roche Diagnostics GmbH in Mannheim, Germany, is 9610126
Roche Diagnostics GmbH in Penzberg, Germany, is 9610529
Roche Diagnostics in the United States is 1823260 |

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1. DEVICE DESCRIPTION

The Elecsys Toxo IgM is a two-step sandwich immunoassay with streptavidin microparticles and electrochemiluminescence detection. In the first incubation10 uL of sample are automatically prediluted 1:20 with Elecsys Diluent Universal and T. gondii-specific recombinant antigen labeled with a ruthenium complex is added. Anti-Toxo IgM antibodies present in the sample react with the ruthenium-labeled T. gondii-specific recombinant antigen. Then biotinylated monoclonal human-IgM- specific antibodies and streptavidin-coated microparticles are added. The complex becomes bound to the solid phase via interaction of biotin and streptayidin. The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell. Application of a voltage to the electrode then induces chemiluminescent emission which is measured by a photomultiplier. Results are determined automatically by the Elecsys software by comparing the electrochemiluminescence signal obtained from the reaction product of the sample with the signal of the cutoff value previously obtained by Toxo IgM calibration.

Reagents 1.1.

The reagent working solutions include:

rackpack (kit placed on instrument)
- Streptavidin coated microparticles, -
- Reagent 1 (Toxoplasma-Ag~ Ru(bpy)2+3) and -
- Reagent 2 (Anti human IgM Ab~biotin). -
- Included with the kit: -
  - . Calibrator 1 (negative calibrator) Human serum non-reactive for anti Toxo IgM
  - . Calibrator 2 (positive calibrator) Human serum reactive for anti Toxo IgM

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1.2. Control

PreciControl Toxo IgM is a ready for use control serum based on human serum. The controls are used for monitoring the accuracy of the Elecsys Toxo IgM immunoassay.

The PreciControl Toxo IgM includes:

PC Toxo IgM 1 (Human serum negative for Toxo IgM antibodies, preservatives) .
PC Toxo IgM 2 (Human serum positive for Toxo IgM antibodies, preservatives) .

2. INDICATIONS FOR USE

The Elecsys Toxo IgM immunoasay is for the in vitro qualitative detection of IgM antibodies to Toxoplasma gondii in human serum and plasma. This assay may be used as an aid in the diagnosis of an acute or recent Toxoplasma gondii infection in suspected patients and pregnant women. Patient testing must be performed in conjunction with an anti-Toxoplasma gondii IgG antibody assay. The electrochemiluminescence immunoassay "ECLIA" is intended for use on Elecsys and cobas e immunoassay analyzers. This assay has not been cleared by the FDA for blood/plasma donor screening.

Comparison with the predicate device

The Elecsys Toxo IgM immunoasay was compared to a commercially marketed kit VIDAS TOXO IgM Test System (K923166) by Biomerieux. Both kits have the same intended use and use the same methodology. Below are tables comparing the reagents and the procedures of the two devices.

Similarities
Item	Device	Predicate
Intended Use	The Elecsys Toxo IgM
immunoassay is for the in
vitro qualitative detection of
IgM antibodies to
Toxoplasma gondii in human
serum and plasma. This
assay may be used as an aid
in the diagnosis of an acute
or recent Toxoplasma gondii	The VIDAS® TOXO IgM
(TXM) assay is intended
for use with a VJDAS®
(Vitek ImmunoDiagnostic
Assay System) instrument
as an automated enzyme-
linked fluorescent
immunoassay (ELFA) for
the presumptive qualitative
Similarities
Item	Device	Predicate
	infection in suspected
patients and pregnant
women. Patient testing must
be performed in conjunction
with an anti- Toxoplasma
gondii IgG antibody assay.
The
electrochemiluminescence
immunoassay “ECLIA” is
intended for use on Elecsys
and cobas e immuno-assay
analyzers. This assay has not
been cleared by the FDA for
blood/plasma donor
screening.
PreciControl Toxo IgM is
used for quality control of
the Elecsys Toxo IgM
immunoassay on the Elecsys
and cobas e immunoassay
analyzers.	detection of anti-
Toxoplasma gondii IgM
antibodies in human serum,
as an aid in the diagnosis of
acute, recent, or reactivated
Toxoplasma gondii
infection. This assay must
be performed in
conjunction with an anti-
Toxoplasma gondii IgG
antibody assay. VIDAS
TXM assay performance
has not been established for
prenatal screening or
newborn testing. This assay
has not been cleared by the
FDA for blood/plasma
donor screening.
Calibrator	Included with the kit	Same
Assay type	Sandwich ELISA	Same
Instrument Platform	Fully automated system	Same
Differences
Item	Device	Predicate
Assay Protocol	Electrochemiluminescence
Immunoassay (ECLIA)	Enzyme-linked fluorescent
immunoassay (ELFA)
Sample type	Serum, lithium heparin
plasma, potassium EDTA
plasma and sodium citrate
plasma	Serum
Calibrators	Two	One

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NON-CLINICAL PERFORMANCE EVALUATION 3.

3.1. Precision

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

7

Precision was determined at one site using Elecsys reagents, human sera and controls in a modified protocol (EP5-A) of the CLSI (Clinical and Laboratory Standards Institute): 6 times daily for 10 days (n = 60). The following results were obtained:

| | | | Repeatability | | Between-run | | Intermediate
precision | |
|-----------------|----|-------------|---------------|--------|-------------|--------|---------------------------|--------|
| Sample | N | Mean [s/co] | SD [s/co] | CV (%) | SD [s/co] | CV (%) | SD [s/co] | CV (%) |
| PCd) Toxo IgM 1 | 60 | 0.146 | 0.004 | 2.5 | 0.003 | 1.9 | 0.005 | 3.2 |
| PC Toxo IgM 2 | 60 | 1.61 | 0.037 | 2.3 | 0.045 | 2.8 | 0.059 | 3.6 |
| Serum Pool 1 | 60 | 0.147 | 0.003 | 2.3 | 0.005 | 3.1 | 0.006 | 3.9 |
| Serum Pool 2 | 60 | 2.06 | 0.075 | 3.7 | 0.031 | 1.5 | 0.082 | 4.0 |
| Serum Pool 3 | 60 | 3.49 | 0.173 | 4.9 | 0.060 | 1.7 | 0.183 | 5.2 |

d) PC = PreciControl

Note: intermediate precision is within lab precision data.

Reproducibility 3.2.

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

Reproducibility was determined at two sites using Elecsys reagents and human sera in a modified protocol (EP5-A) of the CLSI (Clinical and Laboratory Standards Institute): 6 times daily for 10 days at each site (n = 120). The following results were obtained:

			Repeatability		Between-run		Intermediate precision
Sample	N	Mean [s/co]	SD [s/co]	CV (%)	SD [s/co]	CV (%)	SD [s/co]	CV (%)
Serum Pool 1	120	0.161	0.003	1.9	0.006	3.5	0.006	4.0
Serum Pool 2	120	2.01	0.065	3.3	0.03	1.5	0.072	3.6
Serum Pool 3	120	3.37	0.135	4.0	0.073	2.2	0.153	4.6
			Between site		Total precision
Sample	N	Mean [s/co]	SD [s/co]	CV (%)	SD [s/co]	CV (%)
Serum Pool 1	120	0.161	0.021	13.0	0.022	13.6
Serum Pool 2	120	2.01	0.067	3.3	0.098	4.9
Serum Pool 3	120	3.37	0.174	5.2	0.232	6.9

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3.3. Cross-reactivity

A total of 218 potentially cross-reacting samples were collected and tested with the Elecsys Toxo IgM
assay. The results are shown in the table below.

| Antibody or Disease
State | # Tested | Elecsys Positive | % Cross-reactivity |
|------------------------------|--- | AMA | 15 | ANA | 26 | Chlamydia | 5 | CMV | 13 | EBV | 10 | Gonorrhea | 5 | HAV | 10 | HBV* | 21 | HCV | 12 | HIV | 13 | HSV | 9 | Influenza | 16 | Malaria* | 25 | Parvo B19 | 11 | Rubella* | 10 | Syphilis | 5 | TPHA | 4 | VZV | 8 Toxo IgM
-------|------------------------------|--------------------|
| 1 | 6.7 |
| 0 | 0 |
| 0 | 0 |
| 0 | 0 |
| 1 | 10 |
| 0 | 0 |
| 0 | 0 |
| 0* | 4.8 |
| 0 | 0 |
| 0 | 0 |
| 0 | 0 |
| 0 | 0 |
| 1* | 8 |
| 0 | 0 |
| 0* | 10 |
| 0 | 0 |
| 0 | 0 |
| 0 | 0 |

*contains 1 HBV sample repeatedly equivocal by Elecsys and negative with reference, 1 Malaria sample repeatedly equivocal by Elecsys and positive with reference, 1 Rubella sample reactive in Elecsys and initially equivocal with reference (no repetition possible due to low sample volume). Equivocal samples are counted as positive.

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3.4. Matrix equivalency study

Studies were conducted to evaluate the suitability of the following 5 types of blood collectin tubes: serum/gel separation tubes, lithium heparin plasma. K2-EDTA plasma and sodium citrate plasma. A minimum of 49 sample pairs were drawn into serum and plasma collection tubes. The recovery of the analyte in the presence of the anti coagulant was compared to serum. All results met the acceptance criteria.

Limitations - interference 3.5.

The assay is unaffected by:

Compound	Concentration
Bilirubin	0.5 COI recovery ± 20 %.

Samples should not be taken from patients receiving therapy with high biotin doses (i.e. >5 mg/day) until at least 8 hours following the last biotin administration.

No interference was observed from rheumatoid factors up to a concentration of 3720 IU/mL. The high-dose hook effect does not lead to false-negative results in the Elecsys Toxo IgM assay. In vitro tests were performed on 18 commonly used pharmaceuticals and in addition on spiramycine, sulfadiazine, folinic acid and pyrimethamine. No interference with the assay was found.

As with many u-capture assays an interference with unspecific IgM is observed. Increasing amounts of unspecific IgM may lead to a decrease in the recovery of positive samples with the Elecsys Toxo IgM assay.

In rare cases, interference due to extremely high titers of antibodies to immunological components, streptavidin or ruthenium can occur. These effects are minimized by suitable test design.

For diagnostic purposes, the results should always be assessed in conjunction with the patient's medical history, clinical examination and other findings.

*COI= cut off index

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3.6. Hook Effect

For verification of this claim and due to the fact that spiking of the analyte is not possible, three high positive serum samples (single donors), with a COI value of 30.5, 31.9 and 64.5 COI, (based on the measured Elecsys Toxo IgM result) were used for this experiment. It was diluted with native human negative serum in decreasing gradients. All dilution steps were measured in three-fold determination. The median of the signals for each dilution is calculated and, in relation to the dilution factor shown for each dilution in a diagram.

Acceptance criterion: For the Elecsys Toxo IgM assay it is claimed that High-dose Hook effect does not lead to false-negative results

Assay Cut-off 3.7.

The cut-off for the Elecsys Toxo IgM immunoassay was established by the use of sample collectives characterized with commercially available assays.

The classification of samples, based on the cut-off establishment, verification, and validation, is as follows:

Sample results 1.0 COI = Reactive sample .

CLINICAL PERFORMANCE EVALUATION 4.

Summary of clinical performance

To characterize the performance of the Elecsys Toxo IgM immunoassay, relative to an FDA cleared method, multicenter studies in US and EU were performed. In total, 601 samples were tested as detailed below.

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4.1. Study 1

A total of 440 prospective specimens were obtained from US reference laboratory. All specimens represented samples for whom anti Toxo testing had been ordered per clinical routine. The patient population consisted of 162 males and 278 females. There were 158 pregnant women among the females. The patient's age ranged from 2 to 86. The performance of the Elecsys Toxo IgM immunoassay, relative to an FDA cleared method is presented in the table below.

Reference Toxo IgM Method
Elecsys
Toxo IgM		Positive	Equivocal	Negative	Total
	Reactive	2	0	2	4
	Equivocal	0	0	4	4
	Non-reactive	0	1	431	432
	Total	2	1	437	440

US prospectively collected overall patient population

| Agreement Classification | Numerator/
Denominator | Percent
Agreement | 95 % Confidence
Interval |
|--------------------------|---------------------------|----------------------|-----------------------------|
| Positive agreement | 2/3 | 66.7 | 9.43 - 99.2 |
| Negative agreement | 431/437 | 98.6 | 97.0 - 99.5 |

Equivocals are counted as discrepant results against the Elecsys.

4.2. Study 2

A total of 60 retrospective samples were obtained from a US commercial sample vendor. The patient population consisted of 4 males and 56 females. There were 50 pregnant women among the females. All specimens represented samples from whom anti-Toxo testing had been ordered per clinical routine. The performance of the Elecsys Toxo IgM immunoassay, relative to an FDA cleared method is presented in the table below.

US retrospectively collected overall patient population

Reference Toxo IgM Method
---------------------------	--

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| Elecsys

	Negative	Total
Reactive	0	0
Equivocal	1	1
Non-reactive	59	59
Total	60	60

| Agreement Classification | Numerator/
Denominator | Percent
Agreement | 95 % Confidence
Interval |
|--------------------------|---------------------------|----------------------|-----------------------------|
| Positive agreement | 0/0 | NA | NA |
| Negative agreement | 59/60 | 98.3 | 91.1 - 100 |

4.3. Study 3

One hundred one (101) samples collected prospectively were obtained from the general population in Europe under suspicion of Toxoplasmosis consisting of 5 males and 96 females with an age range of 22 to 69. The agreement results are shown below.

EU prospectively collected overall patient population

Reference Toxo IgM Method
Elecsys
Toxo IgM		Positive	Equivocal	Negative	Total
	Reactive	81	1	5	87
	Equivocal	0	1	1	2
	Non-reactive	4	1	7	12
	Total	85	3	13	101

| Agreement Classification | Numerator/
Denominator | Percent
Agreement | 95 % Confidence
Interval |
|--------------------------|---------------------------|----------------------|-----------------------------|
| Positive agreement | 81/86 | 94.2 | 87.0 - 98.1 |
| Negative agreement | 7/14 | 50.0 | 23.0 - 77.0 |

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Equivocals are counted as discrepant results against the Elecsys. In case of unanimously equivocal samples, samples will not be considered for agreement calculation.

Of the 101 prospectively collected European specimens described above, 87 were from pregnant women. The agreement results are shown below.

Reference Toxo IgM Method
Elecsys
Toxo IgM		Positive	Equivocal	Negative	Total
	Reactive	68	0	5	73
	Equivocal	0	1	1	2
	Non-reactive	4	1	7	12
	Total	72	2	13	87

EU prospectively collected pregnant women

| Agreement Classification | Numerator/
Denominator | Percent
Agreement | 95 % Confidence
Interval |
|--------------------------|---------------------------|----------------------|-----------------------------|
| Positive agreement | 68/73 | 93.2 | 84.7 - 97.7 |
| Negative agreement | 7/13 | 53.9 | 25.1 - 80.8 |

Equivocals are counted as discrepant results against the Elecsys. In case of unanimously equivocal samples, samples will not be considered for agreement calculation.

CONCLUSIONS 5.

The information provided in this Premarket Notification [510(k)] shows that the device Elecsys Toxo IgM is safe and effective and will support a substantial equivalence determination to the predicate device, VIDAS TOXO IgM Test System (K923166).