K980810 · Quest Intl., Inc. · LJM · May 12, 1998 · Immunology
Device Facts
Record ID
K980810
Device Name
SERAQUEST ANTI-SSA
Applicant
Quest Intl., Inc.
Product Code
LJM · Immunology
Decision Date
May 12, 1998
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 866.5100
Device Class
Class 2
Indications for Use
For the qualitative and semi-quantitative detection of human antibodies to SSA nuclear antigen in human serum by enzyme immunoassay. For use as an aid in the diagnosis of systemic rheumatic disease, particularly Sjogren's Syndrome. For manual use, or for use with the HyPrep System Plus. For In Vitro Diagnostic Use Only.
Device Story
SeraQuest Anti-SSA is a solid-phase enzyme immunoassay (EIA) for detecting IgG antibodies against SSA nuclear antigen in human serum. The test uses microwells coated with SSA antigen (derived from calf thymus). Patient serum is incubated in the wells; if anti-SSA antibodies are present, they bind to the antigen. After washing, a goat anti-human IgG conjugate labeled with alkaline phosphatase is added. Following a second incubation and wash, p-Nitrophenyl phosphate substrate is added, producing a yellow end-product measured photometrically at 405 nm. The device is intended for manual use or with the HyPrep System Plus semi-automated fluid handler in clinical laboratory settings. Results are reported as Index values based on an in-house standard. The assay aids clinicians in diagnosing systemic rheumatic diseases, specifically Sjogren's Syndrome, by identifying the presence of specific autoantibodies.
Clinical Evidence
Clinical study compared SeraQuest Anti-SSA to the Shield Diastat Anti-SSA test using 288 human serum specimens. Results showed 74 positive and 200 negative concordant results. Relative sensitivity was 96.1% (95% CI: 91.8-100%) and relative specificity was 96.1% (95% CI: 93.5-98.8%). Overall agreement was 96.1% (95% CI: 93.9-98.4%).
Technological Characteristics
Solid-phase enzyme immunoassay (EIA) in plastic microwells. Antigen source: Calf thymus. Conjugate: Goat anti-human IgG labeled with alkaline phosphatase. Substrate: p-Nitrophenyl phosphate. Stop reagent: 0.5 M Trisodium phosphate. Readout: Spectrophotometric at 405 nm. Manual or semi-automated (HyPrep System Plus) operation. Room temperature incubation.
Indications for Use
Indicated for qualitative and semi-quantitative detection of IgG antibodies to SSA in human serum as an aid in the diagnosis of systemic rheumatic disease, particularly Sjogren's Syndrome. For in vitro diagnostic use.
Regulatory Classification
Identification
An antinuclear antibody immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoimmune antibodies in serum, other body fluids, and tissues that react with cellular nuclear constituents (molecules present in the nucleus of a cell, such as ribonucleic acid, deoxyribonucleic acid, or nuclear proteins). The measurements aid in the diagnosis of systemic lupus erythematosus (a multisystem autoimmune disease in which antibodies attack the victim's own tissues), hepatitis (a liver disease), rheumatoid arthritis, Sjögren's syndrome (arthritis with inflammation of the eye, eyelid, and salivary glands), and systemic sclerosis (chronic hardening and shrinking of many body tissues).
Predicate Devices
Shield Diastat Anti-SSA test
Reference Devices
Gardner, M.J. and Altman, D.G., Confidence Intervals Rather Than Hypothesis Testing. Brit. Med. J., 292: 746-750. 1986.
Submission Summary (Full Text)
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33181 Quest International, Inc., 1938 N.E. 148th Terrace, N. Miami, FL Page No. 125
MAY 1 2 1998
## 510(k) SUMMARY
| Applicant: | Quest International, Inc.<br>1938 N.E. 148th Terrace<br>North Miami, FL 33181 |
|---------------------|-------------------------------------------------------------------------------|
| Registration No. | 1061839 |
| Contact Person: | Robert A. Cort, V.P., Quality Assurance |
| Telephone: | (305) 948-8788 |
| Telefax: | (305) 948-4876 |
| Manufacturing Site: | Same as above |
| Device: | SeraQuest® Anti-SSA |
| Device Name: | Antinuclear antibody immunological test system (21CFR § 866.5100) |
Device Classification: Class II (performance standards)
### Description:
The SeraQuest Anti-SSA test is a solid-phase enzyme immunoassay (EIA), which is performed in microwells, at room temperature, in three thirty minute incubations. It has been developed to detect IgG antibodies which are directed against SSA nuclear antigen (Anti-SSA) , in human serum.
The Calibrators in the SeraQuest Anti-SSA test set have been assigned Index values based on an in-house standard. Test results are reported as Index values.
# Principle:
Diluted samples are incubated in wells coated with SSA antigen. Antibodies against SSA (if present) are immobilized in the wells. Residual sample is eliminated by washing and conjugate (enzyme-labeled antibodies to human IgG) is added and incubated. If IgG antibodies to SSA are present, the conjugate will be immobilized in the wells. Residual conjugate is eliminated by washing and draining, and the enzyme substrate is added and incubated. In the presence of the enzyme, the substrate is converted to a yellow end-product which is read photometrically at 405 nm.
### Intended Use:
For the qualitative and semi-quantitative detection of human antibodies to SSA nuclear antigen in human serum by enzyme immunoassay. For use as an aid in the diagnosis of systemic rheumatic
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disease, particularly Sjogren's Syndrome. For manual use, or for use with the HyPrep System Plus. For In Vitro Diagnostic Use Only.
#### Predicate Device:
The SeraQuest Anti-SSA test is substantially equivalent in intended use and performance, to the Shield Diastat Anti-SSA test, Shield Diagnostics, Dundee, DD2 1SW.
### Summary of technological characteristics:
| Characteristic | SeraQuest Anti-SSA | Shield Diastat Anti-SSA |
|-----------------------------------|---------------------------------------------------------------|---------------------------------------------------------------|
| Description: | Enzyme Immunoassay | Enzyme Immunoassay |
| Intended Use: | The detection of<br>antibodies against SSA<br>in human serum. | The detection of<br>antibodies against SSA<br>in human serum. |
| Solid Phase: | Plastic Microwell | Plastic Microwell |
| Antigen Source: | Calf Thymus | Calf Thymus |
| Number of Incubation Periods: | Three | Three |
| Sample Dilution: | 1:50 | 1:500 |
| Sample Incubation<br>Duration: | 30 minutes | 60 minutes |
| Incubation Temperature: | Room temperature | Room temperature |
| Enzyme-labeled Conjugate: | | |
| Antibody | Goat anti-human IgG | Goat anti-human IgG |
| Enzyme | Alkaline phosphatase | Alkaline phosphatase |
| Conjugate Volume: | 100 μl | 100 μl |
| Conjugate Incubation<br>Duration: | 30 minutes | 30 minutes |
| Substrate: | p-Nitrophenyl<br>phosphate | phenolthalein<br>monophosphate |
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Quest International, Inc., 1938 N.E. 148th Terrace, N. Miami, FL 33181 Page No. / 27
... .. .
| Subtrate Volume: | 100 µl | 100 µl |
|-----------------------------------|------------------------------|----------------------------------|
| Substrate Incubation<br>Duration: | 30 minutes | 30 minutes |
| Stop Reagent: | 0.5 M Trisodium<br>phosphate | Sodium<br>Hydroxide |
| Stop Reagent Volume: | 100 µl | 100 µl |
| Readout: | Spectrophotometric<br>405 nm | Spectrophotometric<br>540-565 nm |
Summary of Clinical Testing:
Of the 288 specimens tested, 74 were positive, and 200 were negative in both the SeraQuest and Shield tests (please see Table C-3). Of the remaining specimens which were negative by the Shield test, 8 were positive and 2 equivocal by the SeraQuest test; 4 specimen which were positive by the Shield test, one was equivocal and 3 negative in the SeraQuest test. Refer to table 1 below.
#### TABLE 1.
RESULTS OF SeraQuest Anti-SSA ASSAYS AND SHIELD Anti-SSA ASSAYS OF 288 SERUM SPECIMENS.
SeraQuest ANTI-SSA
Shields ANTI-SSA
| | Positive | Equivocal | Negative | | % | 95% CI* |
|----------|----------|-----------|----------|---------------------------------------------|------|------------------------------|
| Positive | 74 | 1 | 3 | Relative sensitivity√ | 96.1 | 91.8 to 100 |
| Negative | 8 | 2 | 200 | Relative specificity√<br>Overall agreement√ | 96.1 | 93.5 to 98.8<br>93.9 to 98.4 |
- イ Excluding equivocal results.
- ★ Calculated by the exact method.
- ** Calculated by the normal method.
Reference: Gardner, M.J. and Altman, D.G., Confidence Intervals Rather Than Hypothesis Testing. Brit. Med. J., 292: 746-750. 1986.
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Image /page/3/Picture/1 description: The image shows the seal of the Department of Health & Human Services - USA. The seal features a stylized eagle with three lines representing its body and wings. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular fashion around the eagle.
Public Health Service
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
MAY 1 2 1998
Robert A. Cort Vice President, Quality Assurance QUEST INTERNATIONAL, INC. 1938 N.E. 148th Terrace North Miami, FL 33181
Re: K980810 Trade Name: SeraQuest® Anti-SSA Regulatory Class: II Product Code: LJM Dated: April 28, 1998 Received: April 28, 1998
Dear Mr. Cort:
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 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 -
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 Butman
Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
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Quest International, Inc., 1938 N.E. 148th Terrace, N. Miami, FL 33181
#### APPENDIX 8
Page of
510(k) Number (if known): _
Device Name: __SeraQuest Anti-SSA
Indications For Use:
- For in vitro diagnostic use only. 1.
- For the qualitative and semi-quantitative detection of IgG antibodies to SSA in 2. human serum by enzyme immunoassay.
- 3. For use as an aid in the diagnosis of systemic rheumatic disease, particularly Sjogren's Syndrome.
- For manual use, or for use with the HyPrep System Plus semi-automated fluid 4. handler.
# (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
| (Division Sign-Off) | |
|-----------------------------------------|---------|
| Division of Clinical Laboratory Devices | |
| 510(k) Number | 1988810 |
| Prescription Use | <div style="text-align:left;">✓</div> |
|----------------------|---------------------------------------|
| (Per 21 CFR 801.109) | |
OR
| Over-The-Counter Use | |
|--------------------------|--|
| (Optional Format 1-2-96) | |
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