← Product Code [MOB](/submissions/IM/subpart-f%E2%80%94immunological-test-systems/MOB) · K974166

# WIELISA MPO ANCA TEST SYSTEM (K974166)

_Wieslab AB · MOB · Feb 17, 1998 · Immunology · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/IM/subpart-f%E2%80%94immunological-test-systems/MOB/K974166

## Device Facts

- **Applicant:** Wieslab AB
- **Product Code:** [MOB](/submissions/IM/subpart-f%E2%80%94immunological-test-systems/MOB.md)
- **Decision Date:** Feb 17, 1998
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 866.5660
- **Device Class:** Class 2
- **Review Panel:** Immunology

## Intended Use

Wielisa MPO ANCA Test Kit. An Enzyme Linked Immunosorbent Assay (ELISA) for the detection and semi-quantitation of IgG antibodies in human serum to MPO (Myeloperoxidase). The assay is used to detect antibodies in a single serum specimen. The results of the assay are to be used as an aid to the diagnosis of Microscopic polyangiitis.

## Device Story

Wielisa MPO ANCA Test Kit is an ELISA-based in vitro diagnostic assay; detects IgG antibodies to myeloperoxidase (MPO) in human serum. Microtiter wells coated with purified MPO; patient serum added; specific antibodies bind to antigen. Unbound components washed away; alkaline phosphatase-labeled anti-human IgG conjugate added; binds to captured antibodies. Substrate solution added; color intensity measured via optical density (OD). Absorbance calculated against calibrator curve; results expressed in arbitrary units. Used in clinical laboratories; performed by trained personnel. Output provides semi-quantitative measurement of MPO-specific IgG; aids clinicians in diagnosing microscopic polyangiitis.

## Clinical Evidence

Clinical performance evaluated using 364 frozen retrospective sera. Sensitivity for microscopic polyangiitis (MP) was 47.1% (95% CI: 33.1-61.0%). Specificity in healthy normals was 100% (95% CI: 97.5-100%) and in RA patients was 100% (95% CI: 82.7-100%). Relative sensitivity and specificity compared to P-ANCA IFA (n=245) were 84.6% and 94.8% respectively. Relative sensitivity and specificity compared to an alternate commercial ELISA (n=129) were 96.0% and 98.8% respectively. Precision studies (intra-assay, inter-assay, and batch-to-batch) and linearity studies were performed.

## Technological Characteristics

Enzyme-linked immunosorbent assay (ELISA) using microtiter strips coated with purified myeloperoxidase. Detection via alkaline phosphatase-labeled anti-human IgG conjugate and substrate solution. Measurement of optical density (OD) via spectrophotometry. Results calculated against a calibrator curve in arbitrary units.

## Regulatory Identification

A multiple autoantibodies immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoantibodies (antibodies produced against the body's own tissues) in serum and other body fluids. Measurement of multiple autoantibodies aids in the diagnosis of autoimmune disorders (disease produced when the body's own tissues are injured by autoantibodies).

## Predicate Devices

- Immunoscan MPO ANCA ELISA Kit

## 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.
>
> Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/).

{0}------------------------------------------------

K974166

# Summary of Safety and Effectiveness Information MPO ANCA Test Kit

FEB 1 7 1998

Wieslab AB Ideon Research Park S-223 70 Lund Sweden Contact person: Dr. Jorgen Wieslander Telephone: 46-46-182840 Date of preparation: Jan 19, 1998

l.

Description of Device: The Wielisa MPO ANCA Test Kit is an enzyme-linked ll. immunosorbent assay (ELISA) for the detection and semi-quantitation of IgG antibodies to myeloperoxidase (MPO) in human sera. The assay is used to detect antibodies in a single serum specimen. The results of the assay are to be used as an aid to the diagnosis of microscopic polyangiitis. FOR IN VITRO DIAGNOSTIC USE.

The wells of the microtiter strips are coated with purified myeloperoxidase. During the first incubation, specific antibodies in diluted serum, will bind to the antigen coating.

The wells are then washed to remove unbound antibodies and other components. A conjugate of alkaline phosphatase-labeled antibodies to human IgG binds to the antibodies in the wells in this second incubation.

After a further washing step. detection of specific antibodies is obtained by incubation with substrate solution. The amount of bound antibodies correlates to the color intensity and is measured in terms of absorbance (optical density (OD)). The absorbance is then calculated against a calibrator curve and the results are given in arbitrary units.

111. Predicate Device

The MPO ANCA test is substantially equivalent to the Immunoscan MPO ANCA ELISA Kit . Equivalence is demonstrated by the following comparative results:

{1}------------------------------------------------

Table 1. Clinical Sensitivity and Specificity. A total of 364 frozen retrospective sera with clinical characterization were assayed. The following table summarizes the results.

| Control and<br>Disease groups | Total<br>number | Negative<br><10 units | Equivocal<br>10-20 units | Positive<br>>20 units |
|-------------------------------|-----------------|-----------------------|--------------------------|-----------------------|
| Healthy Normals:              | 120             | 120                   | 0                        | 0                     |
| WG:                           | 70              | 57                    | 4                        | 9                     |
| MP:                           | 55              | 27                    | 4                        | 24                    |
| SLE:                          | 40              | 33                    | 6                        | 1                     |
| RA:                           | 17              | 17                    | 0                        | 0                     |
| Anti-GBM nephritis:           | 62              | 34                    | 11                       | 17                    |

MP = microscopic polyangiitis GBM = glomerular basement membrane WG = Wegener's granulomatosis, SLE = systemic lupus erythematosus RA = rheumatoid arthritis

# Clinical Sensitivity (Equivocal samples excluded from calculations)

| WG = 9/66 = 13.6%   | 95% confidence interval = 5.2-22.1%  |
|---------------------|--------------------------------------|
| MP = 24/51 = 47.1%  | 95% confidence interval = 33.1-61.0% |
| GBM = 17/51 = 33.3% | 95% confidence interval = 20.1-46.5% |

## Clinical Specificity (Equivocal samples excluded from calculations)

| SLE     | = 33/34 = 97.1%  | 95% confidence interval = 91.3-100%  |
|---------|------------------|--------------------------------------|
| RA      | = 17/17 = 100%   | *95% confidence interval = 82.7-100% |
| Normals | = 120/120 = 100% | *95% confidence interval = 97.5-100% |

The 95% confidence intervals were calculated using the normal method. *The 95% confidence intervals were calculated assuming one false positive.

ﻤ

{2}------------------------------------------------

Table 2 A total of 245 sera were assayed on the Wielisa MPO ANCA Elisa and IFA. The following table summarizes the relative sensitivity and specificity.

#### Relative Sensitivity and Specificity of the Wielisa MPO ANCA Kit Compared to P-ANCA IFA .

|               |          | Wielisa MPO ANCA |           |          |       |
|---------------|----------|------------------|-----------|----------|-------|
|               |          | Positive         | Equivocal | Negative | Total |
| P-ANCA<br>IFA | Positive | 22               | 0         | 4        | 26    |
| P-ANCA<br>IFA | Negative | 11               | 8         | 200      | 219   |
|               | Total    | 33               | 8         | 204      | 245   |

Sera falling in the equivocal range were excluded from the following calculations

|                      |           |          | 95% Confidence Interval |
|----------------------|-----------|----------|-------------------------|
| Relative Sensitivity | = 22/26   | = 84.6 % | 70.5 - 98.8 %           |
| Relative Specificity | = 200/211 | = 94.8 % | 91.7 - 97.9 %           |
| Relative Accuracy    | = 222/237 | = 93.7 % | 90.5 - 96.8 %           |

{3}------------------------------------------------

Table 3 A total of 129 frozen retrospective sera were assayed by the Wielisa MPO ANCA ELISA and by an alternate commercial ELISA. The following table summarizes the relative sensitivity and specificity of the assay.

# Relative Sensitivity and Specificity of the Wielisa MPO Kit Compared to an Alternate ELISA

## MPO Wielisa

|                    | Positive                                                          | Equivocal | Negative                                                   | Total                                        |    |
|--------------------|-------------------------------------------------------------------|-----------|------------------------------------------------------------|----------------------------------------------|----|
| Positive           | 42                                                                | 0         | 2*                                                         | 44                                           |    |
| Alternate<br>ELISA | Equivocal                                                         | 1         | 0                                                          | 19                                           | 20 |
| Negative           | 0                                                                 | 0         | 65                                                         | 65                                           |    |
| Total              | 43                                                                | 0         | 86                                                         | 129                                          |    |
|                    |                                                                   |           | 95% Confidence Interval                                    |                                              |    |
|                    |                                                                   |           |                                                            |                                              |    |
|                    |                                                                   |           |                                                            |                                              |    |
|                    | Relative Sensitivity<br>Relative Specificity<br>Relative Accuracy |           | = 42/44 = 96.0 %<br>= 84/85 = 98.8 %<br>= 126/129 = 97.7 % | 89.2 - 100 %<br>96.5 - 100 %<br>95.0 - 100 % |    |

Sera falling in the equivocal range were considered to be negative.

* Both samples were from normal healthy patients.

{4}------------------------------------------------

## Table 4. Batch to batch variation.

Batch to batch variation was determined by testing seven different samples in duplicate. Results were obtained for four to six different batches.

| Sample | Mean value | SD   | CV % |
|--------|------------|------|------|
| 1      | 23 units   | 6.0  | 26.0 |
| 2      | 73 units   | 4.0  | 5.5  |
| 3      | 149 units  | 28.2 | 18.9 |
| 4      | 20 units   | 2.8  | 14   |
| 5      | 21 units   | 2.5  | 12   |
| 6      | 20 units   | 3.8  | 19   |
| 7      | 23 units   | 1.4  | 6    |

### Table 5. Inter-assay precision.

Inter-assay precision was determined by testing two different samples in duplicate. Results were obtained for six different runs. and the same of the same of the same of the same of the seat of the seat of the seat the seat the seat and

| Sample | Mean value | SD   | CV % |
|--------|------------|------|------|
| 1      | 63 units   | 8.5  | 13.5 |
| 2      | 169 units  | 33.5 | 19.8 |

#### Table 6. Intra-assay precision.

| Intra-assay precision was determined by testing one sample in 80 wells. |            |    |      |  |  |  |
|-------------------------------------------------------------------------|------------|----|------|--|--|--|
| Sample                                                                  | Mean value | SD | CV % |  |  |  |
|                                                                         | 49 units   | .O | 15.6 |  |  |  |

### Table 7. Linearity

The values were determined for serial two-fold dilutions of six positive sera. The values were compared to log2 of dilution by standard linear regression. The data in Table 7 indicates that the assay has a linear relationship with serum dilution.

| Serum | Neat | 1:2 | 1:4                                                                                                                                                                           | 1:8 | 1:16 | 1:32 | 1:64 | r     |
|-------|------|-----|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----|------|------|------|-------|
| 1     | 163  | કર્ | 41                                                                                                                                                                            | 20  | 00   | 2    |      | 0.927 |
| 2     | 74   | રર  | 39                                                                                                                                                                            | 18  | 7    |      |      | 0.996 |
| 3     | 146  | 83  | રે રેણે રહ્યા છે. આ ગામનાં પ્રાથમિક શાળા, આંગણવાડી તેમ જ દૂધની ડેરી જેવી સવલતો પ્રાપ્ય થયેલી છે. આ ગામનાં પ્રાથમિક શાળા, પંચાયતઘર, આંગણવાડી તેમ જ દૂધની ડેરી જેવી સવલતો પ્રાપ | 26  | 12   | ব    |      | 0.951 |
| 4     | 258  | 162 | 112                                                                                                                                                                           | રેર | 34   | 19   | 8    | 0.943 |
| ર     | 310  | 140 | 74                                                                                                                                                                            | 40  | 20   | d    |      | 0.893 |
| ર     | 34   | 23  | 13                                                                                                                                                                            | 7   |      |      |      | 0.989 |

{5}------------------------------------------------

Image /page/5/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized caduceus symbol, which is a staff with two snakes coiled around it, and the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged in a circular pattern around the symbol. The caduceus is black, and the text is also black. The logo is simple and recognizable, and it is used to represent the U.S. Department of Health & Human Services.

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

WEISLAB AB William L. Boteler c/o IMMUNO PROBE, INC. 1306 Bailes Lane, Suite F Frederick, MD 21701

FEB 17 1998

Re : K974166 Trade Name: Wielisa MPO ANCA Test Kit Regulatory Class: II Product Code: MOB 82 Dated: January 19, 1998 Received: January 20, 1998

Dear Mr. Boteler:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to 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). 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.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major requlations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in In addition, FDA may publish further regulatory action. announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

{6}------------------------------------------------

Page 2

Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770)488-7655.

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a leqally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll free number (800) 638-2041 or at (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html"

Sincerely yours,

Steven Autman

Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

{7}------------------------------------------------

Page 1 of 1

K974166 510(k) Number: Not known

Device Name: Wielisa MPO ANCA Test Kit

Indications For Use: Wielisa MPO ANCA Test Kit. An Enzyme Linked Immunosorbent Assay (ELISA) for the detection and semi-quantitation of IgG antibodies in human serum to MPO (Myeloperoxidase). The assay is used to detect antibodies in a single serum specimen. The results of the assay are to be used as an aid to the diagnosis of Microscopic polyangiitis.

Peter E. Maxon
(Division Sign Off)

Division of Clinical Laboratory De 510(k) Number

PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED) xt 「やっしりロア」
-----------------------------------------------------------------------------------------------------------------------------------------------------------------

Concurrence of CDRH, Office of Device Evaluation (ODE) Prescription Use V OR Over-The Counter Use (Optional Format 1-2-96) (Per 21 CFR 801.109)

---

**Source:** [https://fda.innolitics.com/submissions/IM/subpart-f%E2%80%94immunological-test-systems/MOB/K974166](https://fda.innolitics.com/submissions/IM/subpart-f%E2%80%94immunological-test-systems/MOB/K974166)

**Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact).

**Cite:** Innolitics at https://innolitics.com
