← Product Code [PSZ](/submissions/MI/subpart-d%E2%80%94serological-reagents/PSZ) · K041626

# IMMUNOCARD STAT! FLU A & B (K041626)

_Meridian Bioscience, Inc. · PSZ · Mar 16, 2005 · Microbiology · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/MI/subpart-d%E2%80%94serological-reagents/PSZ/K041626

## Device Facts

- **Applicant:** Meridian Bioscience, Inc.
- **Product Code:** [PSZ](/submissions/MI/subpart-d%E2%80%94serological-reagents/PSZ.md)
- **Decision Date:** Mar 16, 2005
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 866.3328
- **Device Class:** Class 2
- **Review Panel:** Microbiology
- **Attributes:** Pediatric

## Intended Use

ImmunoCard STAT!® Flu A&B is a rapid, qualitative, lateral-flow immunoassay for detecting both influenza A and influenza B viral nucleoprotein antigens in human nasal wash, nasopharyngeal aspirate, and nasopharyngeal swab samples. It is designed to test samples from symptomatic patients. It is recommended that all negative test results be confirmed by cell culture.

## Device Story

Rapid, qualitative, lateral-flow immunoassay; detects influenza A and B viral nucleoprotein antigens. Input: nasal wash, nasopharyngeal aspirate, or nasal/nasopharyngeal swab samples mixed with sample diluent buffer. Operation: sample flows through membrane; antigens bind to monoclonal antibody-colloidal gold conjugates; capture antibodies at test positions bind complexes to form visible pink-red lines. Output: visual qualitative result (presence/absence of lines). Used in clinical settings; performed by healthcare professionals. Results aid in diagnosis of influenza A and B; negative results require confirmation by cell culture.

## Clinical Evidence

Performance evaluated across four laboratories using fresh and frozen samples (nasal wash, nasopharyngeal aspirate, and swabs) compared against cell culture. Study included pediatric samples. Results varied by sample type and virus: Flu A sensitivity ranged 73-96%, specificity 90-94%; Flu B sensitivity 40-100%, specificity 100%. Analytical performance included reproducibility testing (100% agreement) and analytical sensitivity/specificity testing against various viral/bacterial strains.

## Technological Characteristics

Lateral-flow immunochromatographic assay. Uses monoclonal antibodies specific for influenza A and B nucleoproteins. Detection via colloidal gold conjugate. Visual readout (pink-red lines). No instrumentation required. Manual test procedure.

## Regulatory Identification

An influenza virus antigen detection test system is a device intended for the qualitative detection of influenza viral antigens directly from clinical specimens in patients with signs and symptoms of respiratory infection. The test aids in the diagnosis of influenza infection and provides epidemiological information on influenza. Due to the propensity of the virus to mutate, new strains emerge over time which may potentially affect the performance of these devices. Because influenza is highly contagious and may lead to an acute respiratory tract infection causing severe illness and even death, the accuracy of these devices has serious public health implications.

## Special Controls

*Classification.* Class II (special controls). The special controls for this device are:(1) The device's sensitivity and specificity performance characteristics or positive percent agreement and negative percent agreement, for each specimen type claimed in the intended use of the device, must meet one of the following two minimum clinical performance criteria:
(i) For devices evaluated as compared to an FDA-cleared nucleic acid based-test or other currently appropriate and FDA accepted comparator method other than correctly performed viral culture method:
(A) The positive percent agreement estimate for the device when testing for influenza A and influenza B must be at the point estimate of at least 80 percent with a lower bound of the 95 percent confidence interval that is greater than or equal to 70 percent.
(B) The negative percent agreement estimate for the device when testing for influenza A and influenza B must be at the point estimate of at least 95 percent with a lower bound of the 95 percent confidence interval that is greater than or equal to 90 percent.
(ii) For devices evaluated as compared to correctly performed viral culture method as the comparator method:
(A) The sensitivity estimate for the device when testing for influenza A must be at the point estimate of at least 90 percent with a lower bound of the 95 percent confidence interval that is greater than or equal to 80 percent. The sensitivity estimate for the device when testing for influenza B must be at the point estimate of at least 80 percent with a lower bound of the 95 percent confidence interval that is greater than or equal to 70 percent.
(B) The specificity estimate for the device when testing for influenza A and influenza B must be at the point estimate of at least 95 percent with a lower bound of the 95 percent confidence interval that is greater than or equal to 90 percent.
(2) When performing testing to demonstrate the device meets the requirements in paragraph (b)(1) of this section, a currently appropriate and FDA accepted comparator method must be used to establish assay performance in clinical studies.
(3) Annual analytical reactivity testing of the device must be performed with contemporary influenza strains. This annual analytical reactivity testing must meet the following criteria:
(i) The appropriate strains to be tested will be identified by FDA in consultation with the Centers for Disease Control and Prevention (CDC) and sourced from CDC or an FDA-designated source. If the annual strains are not available from CDC, FDA will identify an alternative source for obtaining the requisite strains.
(ii) The testing must be conducted according to a standardized protocol considered and determined by FDA to be acceptable and appropriate.
(iii) By July 31 of each calendar year, the results of the last 3 years of annual analytical reactivity testing must be included as part of the device's labeling. If a device has not been on the market long enough for 3 years of annual analytical reactivity testing to have been conducted since the device received marketing authorization from FDA, then the results of every annual analytical reactivity testing since the device received marketing authorization from FDA must be included. The results must be presented as part of the device's labeling in a tabular format, which includes the detailed information for each virus tested as described in the certificate of authentication, either by:
(A) Placing the results directly in the device's § 809.10(b) of this chapter compliant labeling that physically accompanies the device in a separate section of the labeling where the analytical reactivity testing data can be found; or
(B) In the device's label or in other labeling that physically accompanies the device, prominently providing a hyperlink to the manufacturer's public Web site where the analytical reactivity testing data can be found. The manufacturer's home page, as well as the primary part of the manufacturer's Web site that discusses the device, must provide a prominently placed hyperlink to the Web page containing this information and must allow unrestricted viewing access.
(4) If one of the actions listed at section 564(b)(1)(A)-(D) of the Federal Food, Drug, and Cosmetic Act occurs with respect to an influenza viral strain, or if the Secretary of Health and Human Services (HHS) determines, under section 319(a) of the Public Health Service Act, that a disease or disorder presents a public health emergency, or that a public health emergency otherwise exists, with respect to an influenza viral strain:
(i) Within 30 days from the date that FDA notifies manufacturers that characterized viral samples are available for test evaluation, the manufacturer must have testing performed on the device with those viral samples in accordance with a standardized protocol considered and determined by FDA to be acceptable and appropriate. The procedure and location of testing may depend on the nature of the emerging virus.
(ii) Within 60 days from the date that FDA notifies manufacturers that characterized viral samples are available for test evaluation and continuing until 3 years from that date, the results of the influenza emergency analytical reactivity testing, including the detailed information for the virus tested as described in the certificate of authentication, must be included as part of the device's labeling in a tabular format, either by:
(A) Placing the results directly in the device's § 809.10(b) of this chapter compliant labeling that physically accompanies the device in a separate section of the labeling where analytical reactivity testing data can be found, but separate from the annual analytical reactivity testing results; or
(B) In a section of the device's label or in other labeling that physically accompanies the device, prominently providing a hyperlink to the manufacturer's public Web site where the analytical reactivity testing data can be found. The manufacturer's home page, as well as the primary part of the manufacturer's Web site that discusses the device, must provide a prominently placed hyperlink to the Web page containing this information and must allow unrestricted viewing access.

## Predicate Devices

- Binax NOW® Flu A + B ([K021649](/device/K021649.md), [K021646](/device/K021646.md))
- BD Directigen® Flu A+B ([K001364](/device/K001364.md))
- Thermo-Biostar Inc. ([K023556](/device/K023556.md))
- QuickVue® Influenza A+ B Test ([K031899](/device/K031899.md))
- Xpect® Flu A/B ([K031565](/device/K031565.md))
- Zstatflu® Test ([K982429](/device/K982429.md))

## 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.
>
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510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION
DECISION SUMMARY

A. 510(k) Number:
K041626

B. Purpose for Submission:
New device

C. Measurand:
Flu A & Flu B antigens

D. Type of Test:
Immunochromatographic test

E. Applicant:
Meridian Bioscience, Inc.

F. Proprietary and Established Names:
ImmunoCard STAT!® Flu A&B

G. Regulatory Information:
1. Regulation section: 866.3330; Influenza virus serological reagents
2. Classification: Class: I
3. Product code: GNX; Antigens, CF, Influenza Virus A, B, C
4. Panel: 83 Microbiology

H. Intended Use:
1. Intended use(s):
ImmunoCard STAT!® Flu A&B is a rapid, qualitative, lateral-flow immunoassay for detecting both influenza A and influenza B viral nucleoprotein antigens in human nasal wash, nasopharyngeal aspirate and nasal and nasopharyngeal swab

{1}

samples. It is designed to test samples from symptomatic patients. It is recommended that all negative test results be confirmed by cell culture.

2. Indication(s) for use:
ImmunoCard STAT!® Flu A&B is a rapid, qualitative, lateral-flow immunoassay for detecting both influenza A and influenza B viral nucleoprotein antigens in human nasal wash, nasopharyngeal aspirate and nasal and nasopharyngeal swab samples. It is designed to test samples from symptomatic patients. It is recommended that all negative test results be confirmed by cell culture.

3. Special conditions for use statement(s):
For prescription use

4. Special instrument requirements:
None

I. Device Description:
The Flu A assay uses monoclonal antibodies specific for influenza A nucleoprotein as both the capture and detection antibodies. The Flu B assay uses monoclonal antibodies specific for influenza B nucleoprotein as both the capture and detection antibodies. Nasal wash or nasopharyngeal aspirate is added to Sample Diluent buffer using the transfer pipette provided with the kit. The diluted sample (approximately 1 in 2 dilution) is added to the sample port of the device. Influenza A or influenza B antigen in the diluted sample binds to the corresponding monoclonal antibody-colloidal gold conjugate as the sample moves through the device. The influenza A capture monoclonal antibody bound to the assay membrane at the test-FLU A position of the device central window binds antigen-influenza A antibody-colloidal gold complex and yields a visible pink-red line. The influenza B capture monoclonal antibody bound to the assay membrane at the test-FLU B position of the device central window binds antigen-influenza B antibody-colloidal gold complex and yields a visible pink-red line. When no antigen is present, no complex is formed and no pink-red line will appear at either the test FLU A or the test FLU B position of the device central window.

J. Substantial Equivalence Information:

1. Predicate device name(s):
Binax NOW® Flu A & Binax NOW® Flu B

2. Predicate 510(k) number(s):
k021649 & k021646

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3. Comparison with predicate:

|  Similarities  |   |   |
| --- | --- | --- |
|  Item | Device | Predicate  |
|  Method and type | Immunochromatography
Rapid test
Qualitative | Immunochromatography
Rapid test
Qualitative  |
|  Differences  |   |   |
|  Item | Device | Predicate  |
|  Specimen Type | Nasal Wash,
Nasopharyngeal Aspirate and
Nasal Swab and
Nasopharyngeal Swab | Nasal wash
Nasopharyngeal Swab  |

K. Standard/Guidance Document Referenced (if applicable):

Not applicable

L. Test Principle:

Immunochromatography

M. Performance Characteristics (if/when applicable):

1. Analytical performance:

a. Precision/Reproducibility:

The reproducibility of ImmunoCard STAT! Flu A&B was determined using a panel of known negative (n = 2), positive (n = 5 Flu A, 5 Flu B) and LOD (n = 2) samples that were coded and randomly sorted to mask their identities. Four of the 10 positive samples were weakly reactive. Each reproducibility panel was tested on three consecutive days by three independent test sites. All of the samples produced the expected results 100% of the time.

b. Linearity/assay reportable range:

Not applicable

c. Traceability, Stability, Expected values (controls, calibrators, or methods):

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Not applicable

## d. Detection limit:

The analytical sensitivity of this assay was established in tests with dilutions of 6 examples of influenza A (VR-95, VR-97, VR-544, VR547, VR-822 and VR-897) and 5 examples of influenza B (VR-101, VR-102, VR-295, VR-790 and VR-823) strains. The lower limit of detection with influenza A strains ranged from 890 to 74,000 virions/mL while the lower limit of detection for influenza B strains ranged from 187 to 630,000 virions/mL.

## e. Analytical specificity:

The specificity of ImmunoCard STAT! Flu A&B was tested utilizing bacterial, viral and yeast strains. Positive and negative respiratory specimens were spiked with $\geq 7.5 \times 10^{7} / \mathrm{mL}$ bacteria or yeast. Virus inoculations were performed at $\geq 1500 \mathrm{TCID}_{50}$ or $\mathrm{CEID}_{50} / \mathrm{mL}$. None of the microorganisms tested yielded a positive result with the influenza-negative samples or interfered with detection of the influenza A and/or B positive samples. Both the negative and positive respiratory samples were positive when spiked with influenza A strain VR-100 or influenza B strain VR-295.

## f. Assay cut-off:

Not applicable

## 2. Comparison studies:

### a. Method comparison with predicate device:

The performance of ImmunoCard STAT! Flu A&B PLUS was evaluated by four independent laboratories (3 located in the US and one outside of the US) using either fresh or frozen samples that were characterized using cell culture. Thirty seven of the samples were obtained from pediatric patients.

## Results by sample type:

Fresh : Wash/Aspirate

|   | IC STAT! Flu A |   |   | IC STAT! Flu B  |   |   |
| --- | --- | --- | --- | --- | --- | --- |
|   | Pos | Neg | Total | Pos | Neg | Total  |
|  Tissue Culture Pos | 12 | 3 | 15 | 2 | 3 | 5  |
|  Tissue Culture Neg | 8 | 110 | 118 | 0 | 128 | 128  |
|  Total | 120 | 113 | 133 | 2 | 131 | 133  |

Correlation - Flu A 122/133 (92%)
Sensitivity 12/15 (80%)
Specificity 110/118 (93%)

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Correlation – Flu B 130/133 (98%)
Sensitivity 2/5 (40%)
Specificity 128/128 (100%)

Fresh: Swab samples

|   | IC STAT! Flu A |   |   | IC STAT! Flu B  |   |   |
| --- | --- | --- | --- | --- | --- | --- |
|   | Pos | Neg | Total | Pos | Neg | Total  |
|  Tissue Culture Pos | 29 | 11 | 40 | 19 | 6 | 25  |
|  Tissue Culture Neg | 2 | 229 | 231 | 0 | 246 | 246  |
|  Total | 31 | 240 | 271 | 19 | 252 | 271  |
|  Correlation – Flu A | 258/271 (95%)  |
| --- | --- |
|  Sensitivity | 29/40 (73%)  |
|  Specificity | 229/231 (91%)  |
|  Correlation – Flu B | 265/271 (98%)  |
| --- | --- |
|  Sensitivity | 19/25 (76%)  |
|  Specificity | 246/246 (100%)  |

Frozen: Wash/Aspirate

|   | IC STAT! Flu A |   |   | IC STAT! Flu B  |   |   |
| --- | --- | --- | --- | --- | --- | --- |
|   | Pos | Neg | Total | Pos | Neg | Total  |
|  Tissue Culture Pos | 23 | 1 | 24 | 2 | 0 | 2  |
|  Tissue Culture Neg | 6 | 52 | 58 | 0 | 80 | 80  |
|  Total | 29 | 53 | 82 | 2 | 80 | 82  |
|  Correlation – Flu A | 75/82 (92%)  |
| --- | --- |
|  Sensitivity | 23/24 (96%)  |
|  Specificity | 52/58 (90%)  |
|  Correlation – Flu B | 82/82 (100%)  |
| --- | --- |
|  Sensitivity | 2/2 (100%)  |
|  Specificity | 80/80 (100%)  |

Frozen: Swab samples

|  IC STAT! Flu A | IC STAT! Flu B  |
| --- | --- |
|  Pos Neg Total | Pos Neg Total  |

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Tissue Culture Pos 37 13 50 6 6 12
Tissue Culture Neg 7 100 107 0 145 145
Total 44 113 157 6 151 157

Correlation – Flu A 137/157 (87%)
Sensitivity 37/50 (74%)
Specificity 100/107 (94%)

Correlation – Flu B 151/157 (96%)
Sensitivity 6/12 (50%)
Specificity 145/145 (100%)

b. Matrix comparison:
Not applicable

3. Clinical studies:
a. Clinical Sensitivity:
Not applicable
b. Clinical specificity:
Not applicable
c. Other clinical supportive data (when a. and b. are not applicable):
Not applicable

4. Clinical cut-off:
Not applicable

5. Expected values/Reference range:
Not applicable

N. Proposed Labeling:
The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.

O. Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.

---

**Source:** [https://fda.innolitics.com/submissions/MI/subpart-d%E2%80%94serological-reagents/PSZ/K041626](https://fda.innolitics.com/submissions/MI/subpart-d%E2%80%94serological-reagents/PSZ/K041626)

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