HERPES GROUP IGG ELISA TEST SYSTEM

K963645 · Armkel, LLC · LGC · Feb 4, 1997 · Microbiology

Device Facts

• Record ID: K963645
• Device Name: HERPES GROUP IGG ELISA TEST SYSTEM
• Applicant: Armkel, LLC
• Product Code: LGC · Microbiology
• Decision Date: Feb 4, 1997
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 866.3305
• Device Class: Class 2

Intended Use

The Herpes Group IgG ELISA kit is an Enzyme-Linked Immunosorbent Assay (ELISA) for qualitative determination of IgG antibodies in human serum to Herpes simplex virus. The Herpes Group IgG ELISA kit may be used to evaluate paired sera for the presence of seroconversions of IgG as an aid in the diagnosis of Herpes simplex virus infection.

Device Story

ELISA test kit for qualitative detection of IgG antibodies to Herpes simplex virus in human serum; utilizes purified Herpes Group antigen attached to solid-phase microtiter wells. Patient serum added to wells; if specific IgG antibodies present, they bind to antigen. After incubation and washing, enzyme-labeled anti-human IgG conjugate added; binds to captured patient antibodies. Substrate solution added; enzyme presence triggers color change. Reaction stopped; color intensity measured photometrically. Indirect measurement of specific antibody concentration. Used in clinical laboratories; performed by laboratory technicians. Results interpreted by healthcare providers to aid in diagnosis of Herpes simplex virus infection via seroconversion evaluation.

Clinical Evidence

Four-site comparative study (n=603) against predicate ELISA assays; relative sensitivity 98.9% (95% CI: 97.9-100%), relative specificity 96.7% (95% CI: 94.2-99.1%). Inter-site precision study (n=90) showed CV <15% for most samples. Paired serum study (n=11 evaluable pairs) showed 100% sensitivity versus Complement Fixation (CF) for seroconversion detection. Cross-reactivity testing confirmed no interference from EBV, CMV, or VZV antibodies. CDC-characterized panel (n=72 samples) showed 96.9% total agreement.

Technological Characteristics

Enzyme-Linked Immunosorbent Assay (ELISA); solid-phase microtiter well format. Purified Herpes Group antigen coating. Photometric detection of colorimetric substrate reaction. Manual or automated laboratory processing. No specific materials or software algorithms described beyond standard ELISA biochemical principles.

Indications for Use

Indicated for qualitative detection of IgG antibodies to Herpes simplex virus in human serum to aid in the diagnosis of Herpes simplex virus infection by evaluating paired sera for seroconversion.

Regulatory Classification

Identification

Herpes simplex virus serological assays are devices that consist of antigens and antisera used in various serological tests to identify antibodies to herpes simplex virus in serum. Additionally, some of the assays consist of herpes simplex virus antisera conjugated with a fluorescent dye (immunofluorescent assays) used to identify herpes simplex virus directly from clinical specimens or tissue culture isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by herpes simplex viruses and provides epidemiological information on these diseases. Herpes simplex viral infections range from common and mild lesions of the skin and mucous membranes to a severe form of encephalitis (inflammation of the brain). Neonatal herpes virus infections range from a mild infection to a severe generalized disease with a fatal outcome.

Special Controls

*Classification.* Class II (special controls). The device is classified as class II (special controls). The special control for the device is FDA's revised guidance document entitled “Class II Special Controls Guidance Document: Herpes Simplex Virus Types 1 and 2 Serological Assays.” For availability of the guidance revised document, see § 866.1(e).

Predicate Devices

• Clarks HSV I and HSV II ELISA tests

Submission Summary (Full Text)

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FEB - 4 1997
K963645

# Summary of Safety and Effectiveness Information
## Herpes Group IgG ELISA Test Kit

I. Immuno Probe Inc.
1306 Bailes Lane, Suite F
Frederick, Maryland 21701
Contact person: William Boteler
Telephone: [phone]
Date of preparation: Jan 23, 1997

## II. Description of Device

The Herpes Group IgG ELISA kit is an Enzyme-Linked Immunosorbent Assay (ELISA) for qualitative determination of IgG antibodies in human serum to *Herpes simplex* virus. The Herpes Group IgG ELISA kit may be used to evaluate paired sera for the presence of seroconversions of IgG as an aid in the diagnosis of *Herpes simplex* virus infection.

The Herpes Group IgG ELISA test is an enzyme linked immunosorbent assay to detect IgG antibodies to *Herpes simplex* virus. Purified Herpes Group antigen is attached to a solid phase microtiter well. Diluted test sera is added to each well. If the antibodies are present that recognize the antigen, they will bind to the antigen in the well. After incubation the wells are washed to remove unbound antibody. An enzyme labeled anti-human IgG is added to each well. If antibody is present it will bind to the antibody attached to the antigen on the well. After incubation the wells are washed to remove unbound conjugate. A substrate solution is added to each well. If enzyme is present the substrate will undergo a color change. After an incubation period the reaction is stopped and the color intensity is measured photometrically, producing an indirect measurement of specific antibody in the patient specimen.

## III. Predicate Device

The Herpes Group IgG ELISA test is substantially equivalent to Clarks HSV I and HSV II ELISA tests. Equivalence is demonstrated by the following comparative results:

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# Performance Characteristics

1. Relative sensitivity and specificity. Four different sites compared the Wampole Herpes Group IgG ELISA test relative to Clarks HSV1 and HSVII ELISA assays. The first site was a R&amp;D laboratory at a commercial company located in Maryland. The frozen sera were from normals with ages from 12-83, with various gender, and geographical areas. The results of the study are compiled and summarized in Table 1.

Note: Please be advised the “relative” refers to the comparison of this assay’s results to that of a similar assay. There was not an attempt to correlate the assay’s results with disease presence or absence. No judgment can be made on the comparison assay’s accuracy to predict disease.

## Table 1
Comparison of Herpes Group IgG ELISA and Clark HSV 1 and HSV 2 Study 1

| Wampole Herpes Group IgG ELISA | | | | | |
| --- | --- | --- | --- | --- | --- |
| | | + | eq | - | Total |
| Clark
HSV 1 &
HSV 2 | +* | 104 | 1 | 1 | 106 |
| | eq** | 3 | 0 | 0 | 3 |
| | -*** | 4 | 2 | 72 | 78 |
| | Total | 111 | 3 | 73 | 187 |
| Relative Sensitivity = 104/105 = 99.1% | | | 95% Confidence interval = 97.2% - 100% | | |
| Relative Specificity = 72/76 = 94.7% | | | 95% Confidence interval = 89.6% - 99.9% | | |
| Relative Agreement = 176/181 = 97.2% | | | 95% Confidence interval = 94.8% - 99.7% | | |

Equivocals were not included in the above calculations.

The 95% confidence intervals were calculated using the normal method.

* Indicates positive on Clark HSV 1 and/or Clark HSV 2.
** Indicates equivocal on Clark HSV 1 and/or Clark HSV 2.
*** Indicates negative on both Clark HSV 1 and Clark HSV 2.

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The second site was a R&amp;D laboratory at a commercial company located in New York. The frozen sera were from normals with ages from 17-59, with various gender, and geographical areas. The results of the study are compiled and summarized in Table 2.

## Table 2
Comparison of Herpes Group IgG ELISA and Clark HSV 1 and Clark HSV 2 Study 2

| Wampole Herpes Group IgG ELISA | | | | | |
| --- | --- | --- | --- | --- | --- |
| | | + | eq | - | Total |
| Clark HSV 1 and HSV 2 | +* | 92 | 6 | 2 | 100 |
| | eq** | 1 | 0 | 0 | 1 |
| | -*** | 0 | 0 | 51 | 51 |
| | Total | 93 | 6 | 53 | 152 |

Relative Sensitivity = 92/94 = 97.9% 95% Confidence interval = 94.9% - 100%
Relative Specificity = 51/51 = 100% 95% Confidence interval = 94.2% - 100%
Relative Agreement = 143/145 = 98.6% 95% Confidence interval = 96.7% - 100%

Equivocals were not included in the above calculations.
The 95% confidence intervals were calculated using the normal method.
The 95% confidence interval for specificity was calculated assuming one false positive.

* Indicates positive on Clark HSV 1 and/or Clark HSV 2.
** Indicates equivocal on Clark HSV 1 and/or Clark HSV 2.
*** Indicates negative on both Clark HSV 1 and Clark HSV 2.

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The third site was a clinical laboratory located in Pennsylvania. The sera were prospective samples sent in to the lab for Herpes antibody testing. The results of the studies are compiled and summarized in Table 3.

Table 3
Comparison of Herpes Group IgG ELISA and Clark HSV 1 and Clark HSV 2 Study 3

| | | Wampole Herpes Group IgG ELISA | | | |
| --- | --- | --- | --- | --- | --- |
| | | + | eq | - | Total |
| Clark HSV 1 and HSV 2 | +* | 112 | 0 | 1 | 113 |
| | eq** | 1 | 0 | 1 | 2 |
| | -*** | 3 | 4 | 54 | 61 |
| | Total | 116 | 4 | 56 | 176 |

Relative Sensitivity = 112/113 = 99.1% 95% Confidence interval = 97.4% - 100%
Relative Specificity = 54/57 = 94.7% 95% Confidence interval = 88.8% - 100%
Relative Agreement = 166/170 = 97.7% 95% Confidence interval = 95.3% - 100%

Equivocals were not included in the above calculations.
The 95% confidence intervals were calculated using the normal method.

* Indicates positive on Clark HSV 1 and/or Clark HSV 2.
** Indicates equivocal on Clark HSV 1 and/or Clark HSV 2.
*** Indicates negative on both Clark HSV 1 and Clark HSV 2.

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The forth site was a clinical laboratory located in Wisconsin. The frozen sera were random normal samples. The results of the studies are compiled and summarized in Table 4.

# Table 4
## Comparison of Herpes Group IgG ELISA and Clark Herpes 1 &amp; 2 Study 4

### Wampole Herpes Group IgG ELISA

| | | + | eq | - | Total |
| --- | --- | --- | --- | --- | --- |
| Clark
Herpes 1 & 2 | +* | 62 | 0 | 0 | 62 |
| | eq** | 0 | 0 | 0 | 0 |
| | -*** | 1 | 0 | 25 | 26 |
| | Total | 63 | 0 | 25 | 88 |

Relative Sensitivity = 62/62 = 100.0% 95% Confidence interval = 95.3% - 100%
Relative Specificity = 25/26 = 96.2% 95% Confidence interval = 96.2% - 100%
Relative Agreement = 87/88 = 98.9% 95% Confidence interval = 98.9% - 100%

Equivocals were not included in the above calculations.
The 95% confidence intervals were calculated using the normal method.
The 95% confidence interval for sensitivity was calculated assuming one false negative.

* Indicates positive on Clark HSV 1 and/or Clark HSV 2.
** Indicates equivocal on Clark HSV 1 and/or Clark HSV 2.
*** Indicates negative on both Clark HSV 1 and Clark HSV 2.

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The results of the four studies are compiled and summarized in Table 5.

# Table 5
Comparison of Herpes Group IgG ELISA and Clark HSV 1 and HSV 2

| Wampole Herpes Group IgG ELISA | | | | | |
| --- | --- | --- | --- | --- | --- |
| | | + | eq | - | Total |
| Clark
HSV 1 &
HSV 2 | +* | 370 | 7 | 4 | 381 |
| | eq** | 5 | 0 | 1 | 6 |
| | -*** | 7 | 6 | 203 | 216 |
| | Total | 382 | 13 | 208 | 603 |

Relative Sensitivity = 370/374 = 98.9% 95% Confidence interval = 97.9% - 100%
Relative Specificity = 203/210 = 96.7% 95% Confidence interval = 94.2% - 99.1%
Relative Agreement = 573/584 = 98.1% 95% Confidence interval = 97.0% - 99.2%

Equivocals were not included in the above calculations.
The 95% confidence intervals were calculated using the normal method.

* Indicates positive on Clark HSV 1 and/or Clark HSV 2.
** Indicates equivocal on Clark HSV 1 and/or Clark HSV 2.
*** Indicates negative on both Clark HSV 1 and Clark HSV 2.

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2. Precision. Seven sera were assayed ten times each on three different assays at three different sites. The intersite precision is shown in Table 6. With appropriate technique the user should obtain precision of &lt;15% CV.

Table 6 Herpes Group IgG ELISA Inter Site Precision Study

| (n = 90) | | | |
| --- | --- | --- | --- |
| Sera # | X | SD | CV |
| 1. | 3.81 | 0.351 | 9.21% |
| 2. | 2.03 | 0.255 | 12.6% |
| 3. | 3.16 | 0.287 | 9.08% |
| 4. | 2.01 | 0.272 | 13.5% |
| 5. | 1.31 | 0.198 | 15.1% |
| 6. | 0.09 | 0.109 | 121% |
| 7. | 0.03 | 0.045 | 150% |

3. CF Paired Serum Study. Twenty serum pairs tested by CF from patients suspected of having acute Herpes simplex infection were assayed on the Herpes Group IgG ELISA assay. Each serum pair was evaluated to determine a seroconversion. Six serum pairs could not be evaluated due to the acute being positive.

Three serum pairs could not be evaluated due to the convalescent being negative. The remaining eleven pairs all demonstrated a seroconversion thus giving a 100% sensitivity versus CF for showing a seroconversion in antibody for serum meeting the paired sera criteria.

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4. Cross-Reactivity. Serum containing IgG antibody detectable by ELISA to Epstein Barr Virus, Cytomegalovirus, and Varicella Zoster Virus were assayed. The data summarized in Table 7 indicates that antibodies to these Herpes Viruses do not cross-react with the Herpes IgG ELISA kit.

| SERUM | Herpes Group IgG | EBV VCA | CMV | VZV |
| --- | --- | --- | --- | --- |
| 1 | 0.17 | 2.6 | Negative | 2.7 |
| 2 | 0.05 | 2.3 | Negative | 1.6 |
| 3 | 0.00 | Negative | Negative | 2.2 |
| 4 | 0.00 | 1.8 | Negative | 2.0 |
| 5 | 0.14 | 6.3 | 1.2 | 2.1 |
| 6 | 0.08 | 2.4 | Negative | 3.3 |
| 7 | 0.09 | 1.1 | Negative | 2.1 |
| 8 | 0.12 | 7.2 | 1.1 | 3.2 |
| 9 | 0.18 | Negative | 2.9 | 3.0 |

Sera ≥ 1.10 were considered positive.
Sera ≤ 0.90 were considered negative.

The following information is from a serum panel obtained from the CDC and tested by Wampole Herpes Group IgG ELISA. The results are presented as a means to convey further information on the performance of this assay with a masked, characterized serum panel. This does not imply an endorsement of the assay by the CDC.

The panel consists of 72% positive and 28% negative samples. Excluding two equivocals, the Wampole Herpes Group ELISA demonstrated 96.9% total agreement with the CDC results. Of the results obtained by the Wampole Herpes Group IgG ELISA, excluding two equivocals, there was 95.7% agreement with the positive specimens, and 100% agreement with the negative specimens.