K992241 · Hemagen Diagnostics, Inc. · MSV · Aug 30, 1999 · Immunology
Device Facts
Record ID
K992241
Device Name
VIRGO B2 GLYCOPROTEIN I IGA ANTIBODY KIT
Applicant
Hemagen Diagnostics, Inc.
Product Code
MSV · Immunology
Decision Date
Aug 30, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 866.5660
Device Class
Class 2
Indications for Use
This enzyme-linked immunosorbent assay (ELISA) is intended for the detection and measurement of IgA antibodies to ß, Glycoprotein I in human serum.
Device Story
The VIRGO® β₂ Glycoprotein I IgA Antibody Kit is an ELISA-based in vitro diagnostic test. It uses microwell plates coated with purified human β₂ glycoprotein to capture specific IgA antibodies from patient serum samples. After incubation and washing, a peroxidase-labeled anti-human IgA secondary antibody is added, followed by a substrate that undergoes a color change proportional to the amount of bound antibody. The reaction is stopped and measured using an EIA plate reader. The device is intended for use in clinical laboratories by trained personnel. Results are used by clinicians alongside other clinical and laboratory data to aid in the diagnosis of Antiphospholipid Syndrome (APS). The kit includes a calibrator to assign arbitrary IgA antibody values to patient samples, facilitating semi-quantitative assessment.
Clinical Evidence
Performance evaluated using 50 clinically characterized serum samples (43 Primary APS, 7 SLE+APS) and 120 normal controls. Sensitivity was 70.0% (35/50). Comparative study against a commercially available anti-cardiolipin IgA EIA (n=80) showed 92.6% relative sensitivity (95% CI: 84.7-96.6%), 79.2% relative specificity (95% CI: 69.1-86.7%), and 83.8% relative agreement (95% CI: 74.2-90.3%). Precision studies (inter-assay and intra-assay) demonstrated acceptable CVs.
Technological Characteristics
ELISA-based immunoassay. Components: microwell plates coated with purified human β₂ glycoprotein, peroxidase-labeled goat anti-human IgA (α chain specific) secondary antibody, and substrate. Measures optical density via EIA plate reader. Includes lyophilized human serum-based IgA calibrator. Standardized to IgA standards. No specific ASTM materials cited.
Indications for Use
Indicated for the detection and measurement of circulating IgA antibodies to ß2 Glycoprotein I in human serum. Used in combination with clinical observations and other laboratory findings as an aid in the diagnosis of Antiphospholipid Syndrome. For prescription use only.
Regulatory Classification
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).
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## 510(k) Summary
K992241
#### Submitter's Name/Contact Person 1.
loseph M. Califano Director, Regulatory Affairs
## Address
Hemagen Diagnostics, Inc. 34-40 Bear Hill Road Waltham, MA, 02154
(781) 890-3766 x 257 Phone: (781) 890-3748 Fax: email: jcalifano@hemagen.com
### Date Prepared
14 June 1999
## Date Revised
25 August 1999
#### 2-Device Name
| Trade Name: | VIRGO® β₂ Glycoprotein I IgA Antibody Kit |
|----------------------|---------------------------------------------------|
| Common Name: | β₂ Glycoprotein I Antibodies Test System |
| Classification Name: | Multiple Autoantibodies Immunological Test System |
#### Predicates 3.
Hemagen ® Cardiolipin Antibody Kit Trade Name: 510 (k) Docket No. K 932373, SE Date; 16 July 1993
Hemagen ® Cardiolipin IgA Calibrator Trade Name: 510 (k) Docket No. K 941840, SE Date; 30 June 1994
The performance of the VIRGO ® B2Glycoprotein I IgA Antibody Kit was evaluated with a panel of characterized serum specimens from individuals diagnosed with Primary APS and other diseases.
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#### 3. Description of Device
An enzyme-linked immunosorbent assay (ELISA) designed for the detection and measurement of IgA antibodies to ß, Glycoprotein I in human serum.
The ELISA methodology is commonly used for serum antibody evaluations. Purified human ß, glycoprotein has been attached to the inner surfaces of the microwell plate. During the initial incubation step, specific antibodies in patient serum will bind to the antigen and are immobilized on the surface. After incubation and a wash step, a peroxidase labeled anti human IgA (α chain specific) second antibody is added to the wells to react with the immobilized anti beta 2 GP1 antibodies. After incubation and another wash step, the substrate is added. In the wells where the specific antigen-antibody-HRP complex remains bound, the peroxidase enzyme catalyzes a color change in the substrate. After the enzymatic reaction is stopped, the colored product is read in an ElA plate reader at a specified wavelength.
## 4. Intended Use of Device
This enzyme-linked immunosorbent assay (ELISA) is intended for the detection and measurement of IgA antibodies to ß, Glycoprotein I in human serum.
## 5. Technological Characteristics
## Proposed Device
The VIRGO® ® ß, Glycoprotein I IgA Antibody Kit is an enzyme-linked immunosorbent assay. The device utilizes optical density as a measure of antibody presence, with an established cutoff between a positive and a negative reaction. The device also contains a lgA Calibrator to enable the assignment of arbitrary IgA antibody values to patient samples.
## Predicate Devices
The Hemagen ® Cardiolipin IgG/IgM Antibody Kit is an enzyme-linked immunosorbent assay. The device utilizes optical density as a measure of antibody presence, with an established cutoff between a positive and a negative reaction. The device also contains both an IgM Calibrator, and an IgG Calibrator to enable the assignment of MPL or GPL unit values to patient samples. The calibrators have been standardized to the IgM and IgG standards obtained from Louisville APL Diagnostics, Inc.
The Hemagen ® Cardiolipin IgA Calibrator is Iyophilized processed human serum that contains cardiolipin antibodies of the IgA class. The calibrator has been standardized to the IgA standards obtained from Louisville APL Diagnostics, Inc. Also provided with the calibrator is a second antibody, goat anti-human IgA, conjugated to the enzyme horseradish peroxidase. The IgA calibrator is intended for use with the Hemagen ® Cardiolipin IgG/IgM Antibody Kit to enable users to measure IgA activity levels in serum samples.
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## 5. Performance Data
## Precision
To estimate the overall precision of the VIRGO ® ß2 Glycoprotein I IgA Antibody Kit, inter, and intra assay studies were conducted. The results of these studies is summarized in the tables below
## Inter Assay
Three serum samples, the Negative, and Positive Controls, and the Calibrator were assayed five times each, at least twice a day, on five different days :
| | Mean RAU | Std. Deviation | % C.V. |
|--------------|----------|----------------|--------|
| Sample 1 | 12.9 | 1.7 | 13.2 |
| Sample 2 | 55.1 | 7.9 | 14.3 |
| Sample 3 | 126.0 | 13.2 | 10.5 |
| Neg. Control | < 10 | N/A | N/A |
| Pos. Control | 62.7 | 4.9 | 7.8 |
| Cal Dil 1 | 153.9 | 3.3 | 2.1 |
| Cal Dil 2 | 80.9 | 1.2 | 1.5 |
| Cal Dil 3 | 40.1 | 0.3 | 0.8 |
| Cal Dil 4 | 20.1 | 0.2 | 1.0 |
| Cal Dil 5 | 10.6 | 0.4 | 4.1 |
## Intra Assay
Six serum samples were assayed ten consecutive times in duplicate:
| | Mean RAU | Std. Deviation | % C.V.1 |
|----------|----------|----------------|---------|
| Sample 1 | 13.2 | 1.8 | 13.6 |
| Sample 2 | 13.6 | 1.3 | 9.8 |
| Sample 3 | 24.8 | 2.4 | 9.6 |
| Sample 4 | 53.6 | 5.3 | 10.0 |
| Sample 5 | 57.5 | 7.7 | 13.4 |
| Sample 6 | 116.0 | 7.5 | 6.5 |
1. These values include the well-to-well variation inherent in the plastic strips, which can range up to 5 %, according to the plastic strip supplier.
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## Performance Testing
To demonstrate the effectiveness of the device, a number of clinically characterized serum samples were tested. The results are summarized in the table below:
| Patient Group | Number | Number Positive (%) |
|-----------------|--------|---------------------|
| APS1 | 43 | 30 (69.8) |
| SLE + APS | 7 | 5 (71.4) |
| TOTAL | 50 | 35 (70.0) |
| SLE (No APS) | 20 | 7 (35.0) |
| Scl-70 (No APS) | 20 | 1 (5.0) |
| Infectious2 | 80 | 12 (15.0) |
| Normals | 120 | 6 (5.0) |
### Notes
APS - Primary antiphospholipid syndrorne 1 .
The infectious group consisted of samples with positive syphilis serology. 2.
## Comparison with aCL IgA
The 50 clinically characterized serum samples and 30 serum samples from apparently healthy donors were evaluated with the VIRGO® By Glycoprotein I IgA Antibody Kit, and a commercially available anti-cardiolipin IgA EIA assay. The results are summarized in the table below:
## aCL IgA
| | | Positive | Negative |
|------------|----------|----------|----------|
| IgA β₂ GPI | Positive | 25 | 11 |
| | Negative | 2 | 42 |
| | TOTAL | 27 | 53 |
| Relative Sensitivity: | 92.6%: {84.7 to 96.6 %; 0.95 Confidence Interval} |
|-----------------------|---------------------------------------------------|
| Relative Specificity: | 79.2%: {69.1 to 86.7 %; 0.95 Confidence Interval} |
| Relative Agreement: | 83.8%: {74.2 to 90.3 %; 0.95 Confidence Interval} |
### Conclusion
The results of the both the comparative studies with the predicate device and the performance studies utilizing clinically characterized serum specimens support the claim that the proposed device is capable of effectively detecting IgA antibodies to B, Glycoprotein I in human serum.
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Image /page/4/Picture/0 description: The image is a black and white logo for the Department of Health & Human Services - USA. The logo is circular, with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the top half of the circle. Inside the circle is a stylized image of three human profiles facing to the right, with flowing lines suggesting movement or connection.
DEPARTMENT OF HEALTH & HUMAN SERVICES
AUG 30 1999
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
Mr. Joseph M. Califano Director, Regulatory Affairs Hemagen Diagnostics, Inc. 34-40 Bear Hill Road Waltham, Massachusetts 02154
K992241 Re:
> Trade Name: VIRGO® ß, Glycoprotein I IgA Antibody Kit Regulatory Class: II Product Code: MSV Dated: June 14, 1999 Received: July 1, 1999
Dear Mr. Califano:
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 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). 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 regulations 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 regulatory action. In addition, FDA may publish further 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.
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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 legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific 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 (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Steven Putman
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
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### VIRGO ® ß2 Glycoprotein I IgA Antibody Kit Device Name:
# Indication(s) For Use
..
This enzyme-linked immunosorbent assay (ELISA) is indicated for the detection and This enzyme-linked immunosonent assay (CLOSA) indical servan. The measurement of circulating (g) a minodies to py coproleem and other
presence of these antibodies, in combination with clinical observations and other presence of these antibodies, in combination with clinical obber attendent and the managical pictures pholipid Syndrome.
(PLEASE DO NOT WRITE BELOW THIS LINE)
Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of Clinical Laboratory Devices
| 510(k) Number | K992241 |
|---------------|---------|
|---------------|---------|
| Prescription Use (Per 21 CFR 801.109) | <span style="font-size: 2em;">✓</span> | OR | Over-The-Counter-Use |
|---------------------------------------|----------------------------------------|----|----------------------|
|---------------------------------------|----------------------------------------|----|----------------------|
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