SOFIA (R) STREP A+ FIA

• K Number: K141775
• Device Name: SOFIA (R) STREP A+ FIA
• Manufacturer: QUIDEL CORPORATION
• Date Cleared: 2014-12-16 ( 168 days)
• Product Code: GTY
• Regulation Number: 866.3740

Intended Use

The Sofia® Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.

Device Description

The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia analyzer (Sofia) to detect Group A Streptococcal antigen. The Sofia Strep A FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia. Note: The Cassette, now containing the sample, is placed directly inside Sofia for automatically timed development (WALK AWAY Mode). Sofia scans, measures, and interprets the immunofluorescent signal using method-specific algorithms. Sofia will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected, or transmitted via an LIS connection.

Predicate Devices

K123793

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The description mentions "method-specific algorithms" for interpreting the immunofluorescent signal, which is a standard computational process and does not indicate the use of AI or ML. There is no mention of AI, ML, or related concepts like neural networks or training data for the interpretation process.

Therapeutic

No.
The device is a diagnostic tool that aids in the diagnosis of Group A Streptococcal infection by detecting antigens. It does not provide treatment or directly alleviate symptoms.

Diagnostic

Yes
The "Intended Use / Indications for Use" section states that the device is "intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection."

SaMD (Software as a Medical Device)

No

The device description clearly outlines a system that includes a physical analyzer (Sofia analyzer) and a physical test cassette (Cassette) which are integral to the device's function of detecting antigens. While software is used for interpretation and display, it is part of a larger hardware system.

IVD (In Vitro Diagnostic)

Yes, this device is an IVD (In Vitro Diagnostic).

Here's why:

• Intended Use: The intended use explicitly states that the device "detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis... as an aid in the diagnosis of Group A Streptococcal infection." This clearly indicates it's used to test samples taken from the human body to provide information for diagnostic purposes.
• Device Description: The description details how the device analyzes a "patient's swab sample" to detect specific antigens. This process of analyzing a biological sample outside of the body is the core of in vitro diagnostics.
• Performance Studies: The performance studies involve testing "throat swabs" from "patients" and comparing the results to other diagnostic methods (bacterial culture and RT-PCR). This further confirms its use in analyzing human samples for diagnostic purposes.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The Sofia® Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.

Product codes

GTY

Device Description

The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia analyzer (Sofia) to detect Group A Streptococcal antigen.

The Sofia Strep A FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia.

Note: The Cassette, now containing the sample, is placed directly inside Sofia for automatically timed development (WALK AWAY Mode).

Sofia scans, measures, and interprets the immunofluorescent signal using method-specific algorithms. Sofia will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected, or transmitted via an LIS connection.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Throat

Indicated Patient Age Range

Not Found

Intended User / Care Setting

professional and laboratory use

Description of the training set, sample size, data source, and annotation protocol

Not Found

Description of the test set, sample size, data source, and annotation protocol

The performance of the Sofia Strep A+ FIA was compared to standard bacterial culture and identification and an FDA-cleared Group A Streptococcus RT-PCR assay in a multi-center clinical field study. This study was conducted by untrained health care personnel during 2014 at 7 distinct CLIA-waived sites in various geographical regions within the United States. In this multicenter, point-of-care (POC) field trial, two (2) throat swabs were collected from eight hundred fiftyone (851) patients with symptoms suggestive of bacterial pharyngitis.

One throat swab was tested fresh at the CLIA-waived site in the Sofia Strep A+ FIA. A second swab was placed into transport medium and transported on cold ice packs to a central Reference Laboratory. The swab was streaked on a sheep blood agar plate (SBA) and cultured for up to 48 hours. A portion of the transport medium was subsequently tested in the PCR assay. The performance of the Sofia Strep A+ FIA was determined by comparison of the rapid FIA test result to the corresponding culture result (Table 2).

Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)

Sofia Strep A+ FIA Performance vs. Cell Culture and vs. Cell Culture Resolved by PCR

• Study Type: Multi-center clinical field study, point-of-care (POC) field trial.
• Sample Size: 851 patients.
• Key Results:
  • Sensitivity: 93.7% (164/175) with 95% CI = 89.1%-96.5%
  • Specificity: 94.4% (638/676) with 95% CI = 92.4%-95.9%
  • PPV: 81.2% (164/202)
  • NPV: 98.3% (638/649)
  • Of the 38 discordant specimens (Sofia Pos, Culture Neg), 24 were positive for GAS when tested with an FDA-cleared molecular device, 14 were negative.
  • Of the 11 discordant specimens (Sofia Neg, Culture Pos), 3 were negative when tested with an FDA-cleared molecular device, 8 were positive.

Reproducibility Studies

• Study Type: Reproducibility study evaluated at 3 different laboratories.
• Sample Size: Two different operators at each site tested a series of coded, contrived samples.
• Key Results:
  • Inter-laboratory agreement for negative samples was 90-100%.
  • Inter-laboratory agreement for positive samples was 87-100%.
  • Overall inter-laboratory agreement for Negative samples (C₀): 100% (90/90) (95.9-100.0%)
  • Overall inter-laboratory agreement for High Negative samples (C₅): 90% (81/90) (82.1-94.7%)
  • Overall inter-laboratory agreement for Low Positive samples (C₉₅): 87% (78/90) (78.1-92.2%)
  • Overall inter-laboratory agreement for Mod Positive samples (C₁₀₀): 100% (90/90) (95.9-100.0%)
  • Intra-laboratory agreement for all samples ranged from 93-95%.
  • Site 1 Intra-laboratory Agreement: 95% (114/120) (89.5-97.7%)
  • Site 2 Intra-laboratory Agreement: 93% (112/120) (87.4-96.6%)
  • Site 3 Intra-laboratory Agreement: 94% (113/120) (88.5-97.2%)

Limit of Detection (LoD)

• Study Type: Analytical study to determine the lower limit of detection.
• Key Results:
  • LoD ranged from 2.76E+03 to 8.13E+03 colony forming units (cfu)/test using 3 strains of Group A Streptococcus pyogenes.
  • Bruno [CIP 104226]: 4.00E+03 cfu/test
  • CDC-SS-1402: 8.13E+03 cfu/test
  • CDC-SS-1460: 2.76E+03 cfu/test

Analytical Reactivity

• Study Type: Analytical study to demonstrate reactivity with different strains.
• Key Results:
  • Demonstrated using 21 strains of Group A Streptococcus pyogenes tested at 1.74E+04 cfu/test. All strains showed reactivity.

Analytical Specificity (Cross Reactivity)

• Study Type: Analytical study to evaluate cross-reactivity.
• Key Results:
  • Evaluated with 61 non-Group A Streptococcus bacterial and fungal microorganisms, and 26 viral isolates.
  • None of the microorganisms or viruses showed any sign of cross-reactivity in the assay at the tested concentrations. The same microorganisms and viruses were also pre-mixed with Group A Strep and tested in the Sofia Strep A+ FIA.

Interfering Substances

• Study Type: Analytical study to evaluate interference.
• Key Results:
  • Several over-the-counter (OTC) products, whole blood, mucin, and blood agar were evaluated.
  • Nacho Flavor Doritos interfered at 25% w/v.
  • Fresh Whole Blood interfered at 100 µL/swab.
  • Bovine submaxillary mucin interfered at 28.7 mg/mL.

Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)

Sensitivity: 93.7% (164/175) (95%CI=89.1%-96.5%)
Specificity: 94.4% (638/676) (95% CI=92.4%-95.9%)
PPV: 81.2% (164/202)
NPV: 98.3% (638/649)

Predicate Device(s)

Sofia Strep A FIA for use with Sofia, K123793

Reference Device(s)

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information

Not Found

Regulation Number and Section

§ 866.3740

Streptococcus spp. serological reagents.(a)
Identification. Streptococcus spp. serological reagents are devices that consist of antigens and antisera (excluding streptococcal exoenzyme reagents made from enzymes secreted by streptococci) used in serological tests to identifyStreptococcus spp. from cultured isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by bacteria belonging to the genusStreptococcus and provides epidemiological information on these diseases. Pathogenic streptococci are associated with infections, such as sore throat, impetigo (an infection characterized by small pustules on the skin), urinary tract infections, rheumatic fever, and kidney disease.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.

Summary

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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

QUIDEL CORPORATION December 16, 2014 JOHN TAMERIUS SENIOR VICE PRESIDENT, CLINICAL AND REGULATORY 12544 HIGH BLUFF (ADMINISTRATIVE OFFICE LOCATION) SAN DIEGO CA 92130

Re: K141775

Trade/Device Name: Sofia® Strep A+ FIA Regulation Number: 21 CFR 866.3740 Regulation Name: Streptococcus spp. serological reagents Regulatory Class: I Product Code: GTY Dated: June 30, 2014 Received: July 1, 2014

Dear Dr. Tamerius:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and 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) that do not require approval of a premarket approval application (PMA). 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number [phone] or [phone] or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number [phone] or [phone] or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours.

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Sally A. Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration

Indications for Use

510(k) Number (if known) K141775

Device Name Sofia® Strep A+FIA Assay

Indications for Use (Describe)

The Sofia® Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.

Type of Use (Select one or both, as applicable)

X Prescription Use (Part 21 CFR 801 Subpart D)

__ Over-The-Counter Use (21 CFR 801 Subpart C)

PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON A SEPARATE PAGE IF NEEDED.

FOR FDA USE ONLY

Concurrence of Center for Devices and Radiological Health (CDRH) (Signature)

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510(k) SUMMARY

| Submitted By: | Quidel Corporation
12544 High Bluff Drive, Suite 200
(Administrative Offices)
San Diego, California 92130
Telephone: [phone]
Fax: [phone] |
|-----------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Submission Contact: | John D. Tamerius, Ph.D. |
| Date Prepared: | June 30, 2014 |
| Device Trade Name: | Sofia® Strep A+ FIA and Sofia |
| Common Name: | Strep A immunological test system and Fluorometer |
| Predicate Devices: | Sofia Strep A FIA for use with Sofia, K123793 |
| Device Classification/Name: | 21 CFR 866.3740 / Streptococcus Group A
serological reagents |
| Intended Use: | The Sofia Strep A+ FIA detects Group A
Streptococcal antigens from throat swabs from
patients with signs and symptoms of pharyngitis, such
as sore throat. All negative test results should be
confirmed by bacterial culture because negative
results do not preclude Group A Strep infection and
should not be used as the sole basis for treatment.
The test is intended for professional and laboratory
use as an aid in the diagnosis of Group A
Streptococcal infection. |
| Physiologic Basis of the
Test: | Group A Streptococcus is one of the most common
causes of acute upper respiratory tract infection. Early
diagnosis and treatment of Group A Streptococcal
pharyngitis has been shown to reduce the severity of
symptoms and serious complications such as
rheumatic fever and glomerulonephritis.
Conventional procedures for identification of Group A
Streptococcus from throat swabs involve the culture,
isolation, and subsequent identification of viable
pathogen at 24 to 48 hours or longer for results. |

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Device Description: The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia analyzer (Sofia) to detect Group A Streptococcal antigen.

The Sofia Strep A FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia.

Note: The Cassette, now containing the sample, is placed directly inside Sofia for automatically timed development (WALK AWAY Mode).

Sofia scans, measures, and interprets the immunofluorescent signal using method-specific algorithms. Sofia will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected, or transmitted via an LIS connection.

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Device Comparison:

Note: The shaded cells in Table 1 below identify where there are differences between the proposed and predicate devices.

Item	Proposed Device	Predicate Device
Features	Sofia Strep A+ FIA with Sofia	Sofia Strep A FIA with Sofia
Intended Use	The Sofia® Strep A+ FIA detects
Group A Streptococcal antigens
from throat swabs from patients
with signs and symptoms of
pharyngitis, such as sore throat.
All negative test results should be
confirmed by bacterial culture
because negative results do not
preclude Group A Strep infection
and should not be used as the
sole basis for treatment. The test
is intended for professional and
laboratory use as an aid in the
diagnosis of Group A
Streptococcal infection.	The Sofia Strep A FIA employs
immunofluorescence technology to
detect Group A Streptococcal
antigens from throat swabs of
symptomatic patients. All negative
test results should be confirmed by
bacterial culture because negative
results do not preclude Group A
Strep infection and should not be
used as the sole basis for
treatment. The test is intended for
professional and laboratory use as
an aid in the diagnosis of Group A
Streptococcal infection.
FDA File
Number	K141775	K123793
Manufacturer	Quidel Corporation and LRE	Quidel Corporation and LRE
Regulation
Number	21 CFR 866.3740 and
21 CFR 866.2560	21 CFR 866.3740 and
21 CFR 866.2560
Classification
Product Code	GTY and KHO	GTY and KHO
Instrument	Sofia	Sofia
Analyte	Group A Streptococcus	Group A Streptococcus
Automated
Analysis	Yes	Yes
Mode(s)	Walk-Away only	Read-Now and Walk-Away
Read Results	Read results on instrument screen
or print with optional printer	Read results on instrument screen
or print with optional printer
Calibrator	Yes - Calibration Cassette and
QC Card provided	Yes - Calibration Cassette and
QC Card provided
Read Result
Time	5 Minutes	5 Minutes
Specimen
Types	Throat swab	Throat swab
Qualitative	Yes	Yes
Test Principle	Immunofluorescence Device	Immunofluorescence Device
Item	Proposed Device	Predicate Device
Features	Sofia Strep A+ FIA with Sofia	Sofia Strep A FIA with Sofia
Format	Lateral-flow Test Cassette	Lateral-flow Test Cassette
Antibodies
Used	Polyclonal rabbit antibodies that
are specific to Group A
Streptococcus	Polyclonal rabbit antibodies that
are specific to Group A
Streptococcus
Detection
Particle	Polystyrene microparticles dyed
with Europium chelate	Polystyrene microparticles dyed
with Europium chelate
Storage	Room Temperature	Room Temperature
Reagent
Solution	One reagent bottle containing
sodium nitrite and hydrochloric
acid in glass ampoule	One reagent bottle containing
sodium nitrite and acetic acid in
glass ampoule
Transfer
Device	Fixed volume pipette used to
transfer patient sample mixed with
reagent into Test Cassette	Fixed volume pipette used to
transfer patient sample mixed with
reagent into Test Cassette
External
Controls	Test kit contains Positive and
Negative Control Swabs	Test kit contains Positive and
Negative Control Swabs
Quality Control
Features	Built-in features include:
• Built-in procedural control
zone scanned by the
analyzer to determine
whether adequate flow
occurred
• Analyzer prevents used or
expired cartridge from being
read by the reader
• Cassette properly inserted	Built-in features include:
• Built-in procedural control
zone scanned by the
analyzer to determine
whether adequate flow
occurred
• Analyzer prevents used or
expired cartridge from being
read by the reader
• Cassette properly inserted

Table 1

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Summary of Performance Data:

Sofia Strep A+ FIA Performance vs. Cell Culture and vs. Cell Culture Resolved by PCR

The performance of the Sofia Strep A+ FIA was compared to standard bacterial culture and identification and an FDA-cleared Group A Streptococcus RT-PCR assay in a multi-center clinical field study. This study was conducted by untrained health care personnel during 2014 at 7 distinct CLIA-waived sites in various geographical regions within the United States. In this multicenter, point-of-care (POC) field trial, two (2) throat swabs were collected from eight hundred fiftyone (851) patients with symptoms suggestive of bacterial pharyngitis.

One throat swab was tested fresh at the CLIA-waived site in the Sofia Strep A+ FIA. A second swab was placed into transport medium and transported on cold ice packs to a central Reference Laboratory. The swab was streaked on a sheep blood agar plate (SBA) and cultured for up to 48 hours. A portion of the transport medium was subsequently tested in the PCR assay. The performance of the Sofia Strep A+ FIA was determined by comparison of the rapid FIA test result to the corresponding culture result (Table 2).

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Table 2 Sofia Strep A+ FIA Performance Compared to Culture

	Culture
	Pos	Neg	Sensitivity
Sofia Pos	164	38*	93.7% (164/175)
(95%CI=89.1%-96.5%)
Sofia Neg	11**	638	Specificity
			94.4% (638/676)
(95% CI=92.4%-95.9%)
Total:	175	676	PPV
			81.2% (164/202)
			NPV
			98.3% (638/649)

*Of the 38 discordant specimens, 24 of these specimens were positive for GAS when tested with an FDA-cleared molecular device, 14 were negative.

**Of the 11 discordant specimens, 3 were negative when tested with an FDA-cleared molecular device, 8 were positive.

Reproducibility Studies

The reproducibility of the Sofia Strep A+ FIA was evaluated at 3 different laboratories. Two different operators at each site tested a series of coded, contrived samples, prepared in negative clinical matrix, ranging from negative (no bacteria) to moderate positive (3 x LoD) Group A Streptococcus. The inter-laboratory agreement (Table 3) for negative samples was 90-100% and 87-100% for positive samples. The intra-laboratory agreement (Table 4) for all samples ranged from 93-95%.

| Site | Negative*
(C₀) | High Negative*
(C₅) | Low Positive**
(C₉₅) | Mod Positive**
(C₁₀₀) |
|------------------------------------|-----------------------|------------------------|-------------------------|--------------------------|
| 1 | 30/30 | 27/30 | 27/30 | 30/30 |
| 2 | 30/30 | 29/30 | 23/30 | 30/30 |
| 3 | 30/30 | 25/30 | 28/30 | 30/30 |
| Total | 90/90 | 81/90 | 78/90 | 90/90 |
| % Overall
Agreement
(95% CI) | 100%
(95.9-100.0%) | 90%
(82.1-94.7%) | 87%
(78.1-92.2%) | 100%
(95.9-100.0%) |

Table 3 Sofia Strep A+ FIA Reproducibility Study Inter-laboratory Agreement

*Bacteria not detected/total

**Bacteria detected/total

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Table 4 Sofia Strep A+ FIA Reproducibility Study Intra-laboratory Agreement

| Site | Negative*
(Co) | High Negative*
(Cis) | Low Positive**
(C95) | Mod. Positive**
(C100) | % Overall
Agreement
(95% CI) |
|------|-------------------|-------------------------|-------------------------|---------------------------|------------------------------------|
| 1 | 30/30 | 27/30 | 27/30 | 30/30 | 95% (114/120)
(89.5-97.7%) |
| 2 | 30/30 | 29/30 | 23/30 | 30/30 | 93% (112/120)
(87.4-96.6%) |
| 3 | 30/30 | 25/30 | 28/30 | 30/30 | 94% (113/120)
(88.5-97.2%) |

*Bacteria not detected/total

**Bacteria detected/total

Limit of Detection

The limit of detection (LoD) for the Sofia Strep A+ FIA was determined using 3 strains of Group A Streptococcus pyogenes. The LoD ranged from 2.76E+03 to 8.13E+03 colony forming units (cfu)/test (Table 5).

Table 5 Sofia Strep A+ FIA Limits of Detection

Strain	Minimum Detectable Level*
Bruno [CIP 104226]	4.00E+03 cfu/test
CDC-SS-1402	8.13E+03 cfu/test
CDC-SS-1460	2.76E+03 cfu/test

cfu/test = colony forming units/test

*The levels of bacteria were determined by limiting dilution, bacterial culture, and colony counting to give cfu/test.

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Analytical Reactivity

Analytical reactivity for the Sofia Strep A+ FIA was demonstrated using 21 strains of Group A Streptococcus pyogenes tested at 1.74E+04 colony forming units (cfu)/test (Table 6).

Streptococcus pyogenes Strain
Strain #1 (ATCC-19615)
Strain #2 (ATCC-700942)
Strain #3 (ATCC-700952)
Strain #4 (Clinical Isolate-52123)
Strain #5 (Clinical Isolate-52120)
Strain #6 (Clinical Isolate-62055)
Strain #7 (Clinical Isolate-52152)
Strain #8 (Clinical Isolate-62092)
Strain #9 (Clinical Isolate-52151)
Strain #10 (ATCC-700482)
Strain #11 (ATCC-BAA-1315)
Strain #12 (ATCC-700459)
Strain #13 (ATCC-12203)
Strain #14 (ATCC-700944)
Strain #15 (Clinical Isolate-52154)
Strain #16 (Clinical Isolate-5036)
Strain #17 (Clinical Isolate-5095)
Strain #18 (Clinical Isolate-5017)
Strain #19 (Clinical Isolate-5060)
Strain #20 (Clinical Isolate-5112)
Strain #21 (Clinical Isolate-5008)

Table 6 Analytical Reactivity

Analytical Specificity

Cross Reactivity

The cross reactivity of the Sofia Strep A+ FIA was evaluated with a total of 61 non-Group A Streptococcus bacterial and fungal microorganisms, and 26 viral isolates. None of the microorganisms or viruses listed below in Table 7 showed any sign of cross reactivity in the assay. The same microorganisms and viruses in Table 7 were pre-mixed with Group A Strep and tested in the Sofia Strep A+ FIA.

Table 7
Cross Reactivity

Organism/Virus	Test Concentration**
Arcanobacterium haemolyticum	3.00E+05 cfu/test
Bacteroides fragilis	3.00E+07 cfu/test
Bordetella pertussis	3.00E+07 cfu/test
Candida albicans	3.00E+04 cfu/test
Corynebacterium diphtheriae	3.00E+05 cfu/test
Corynebacterium pseudodiphtheriticum*	3.00E+06 cfu/test
Enterococcus faecalis*	1.40E+06 cfu/test
Organism/Virus	Test Concentration**
Enterococcus faecium	3.00E+06 cfu/test
Escherichia coli	1.50E+07 cfu/test
Fusobacterium necrophorum	3.00E+06 cfu/test
Haemophilus influenzae	3.00E+07 cfu/test
Haemophilus parahaemolyticus	3.00E+06 cfu/test
Klebsielle pneumoniae	3.00E+07 cfu/test
Moraxella catarrhalis	3.00E+06 cfu/test
Neisseria gonorrhoeae	3.00E+06 cfu/test
Neisseria lactamica	3.00E+06 cfu/test
Neisseria meningitidis	3.00E+06 cfu/test
Neisseria sicca	3.00E+07 cfu/test
Neisseria subflava	3.00E+07 cfu/test
Proteus vulgaris	3.00E+07 cfu/test
Pseudomonas aeruginosa	3.00E+06 cfu/test
Serratia marcescens	3.00E+07 cfu/test
Staphylococcus aureus*	3.00E+06 cfu/test
Staphylococcus epidermidis	3.00E+06 cfu/test
Staphylococcus haemolyticus	3.00E+05 cfu/test
Staphylococcus intermedius	3.00E+05 cfu/test
Staphylococcus saprophyticus	3.00E+06 cfu/test
Streptococcus anginosus	3.00E+06 cfu/test
Streptococcus gordonii	3.00E+04 cfu/test
Streptococcus mitis	3.00E+04 cfu/test
Streptococcus mutans*	3.00E+06 cfu/test
Streptococcus oralis	3.00E+06 cfu/test
Streptococcus parasanginis*	3.00E+06 cfu/test
Streptococcus pneumoniae	3.00E+06 cfu/test
Streptococcus salivaris	3.00E+05 cfu/test
Streptococcus sanguinis	3.00E+06 cfu/test
Streptococcus Group B Strain #1:
Streptococcus agalactiae	3.00E+06 cfu/test
Streptococcus Group B Strain #2	3.00E+06 cfu/test
Streptococcus Group B Strain #3	3.00E+06 cfu/test
Streptococcus Group B Strain #4	3.00E+06 cfu/test
Streptococcus Group B Strain #5	3.00E+06 cfu/test
Streptococcus Group C Strain #1	3.00E+06 cfu/test
Streptococcus Group C Strain #2	3.00E+06 cfu/test
Streptococcus Group C Strain #3	3.00E+06 cfu/test
Streptococcus Group C Strain #4:
Streptococcus dysgalactiae*	3.00E+06 cfu/test
Organism/Virus	Test Concentration**
Streptococcus Group C Strain #5	3.00E+05 cfu/test
Streptococcus Group D Strain #1:
Enterococcus casseliflavus	3.00E+06 cfu/test
Streptococcus Group D Strain #2	3.00E+06 cfu/test
Streptococcus Group D Strain #3*	3.00E+06 cfu/test
Streptococcus Group D strain #4:
Enterococcus faecalis	3.00E+06 cfu/test
Streptococcus Group D strain #5:
Enterococcus faecalis	3.00E+06 cfu/test
Streptococcus Group F Strain #1	1.00E+05 cfu/test
Streptococcus Group F Strain #2	3.00E+06 cfu/test
Streptococcus Group F Strain #3	1.00E+06 cfu/test
Streptococcus Group F Strain #4*	3.00E+05 cfu/test
Streptococcus Group F Strain #5	3.00E+05 cfu/test
Streptococcus Group G strain #1:
Streptococcus dysgalactiae	3.00E+07 cfu/test
Streptococcus Group G Strain #2	3.00E+06 cfu/test
Streptococcus Group G Strain #3	3.00E+06 cfu/test
Streptococcus Group G Strain #4	3.00E+06 cfu/test
Streptococcus Group G Strain #5	3.00E+06 cfu/test
Adenovirus Type 1*	3.00E+11 TCID50/test
Adenovirus Type 3*	3.00E+05 TCID50/test
Adenovirus Type 4	7.50E+03 TCID50/test
Adenovirus Type 5	3.00E+05 TCID50/test
Adenovirus Type 11	3.00E+04 TCID50/test
Coronavirus 229E	3.00E+04 TCID50/test
Coronavirus OC43	3.00E+04 TCID50/test
Coxsackievirus B5 (Faulkner)	3.00E+06 TCID50/test
Cytomegalovirus (Towne)	3.00E+03 TCID50/test
Echovirus Type 3	1.50E+04 TCID50/test
Epstein Barr Virus (EBV)*	3.00E+07 genome
copies/test
Herpes Simplex Virus 1	3.00E+04 TCID50/test
Herpes Simplex Virus 2	3.00E+04 TCID50/test
Influenza A/New Jersey/8/76 (H1N1)	3.00E+04 TCID50/test
Influenza A/Victoria/3/75 (H3N2)	3.00E+04 TCID50/test
Influenza B/Hong Kong/5/72	3.00E+04 TCID50/test
Influenza B/Panama/45/90	1.50E+04 TCID50/test
Influenza C/Taylor/1233/47	1.50E+04 TCID50/test
Measles (Edmonston)	3.00E+04 TCID50/test
Mumps (Enders)*	3.00E+03 TCID50/test
Organism/Virus	Test Concentration**
Parainfluenza virus 1	3.00E+04 TCID50/test
Parainfluenza virus 2	1.10E+05 TCID50/test
Parainfluenza virus 3	6.80E+05 TCID50/test
Parainfluenza virus 4A	3.00E+04 TCID50/test
Rhinovirus Type 2	3.00E+03 TCID50/test
Rhinovirus Type 15	3.00E+04 TCID50/test

11

12

13

cfu/test = colony forming units/test TCID50/test = 50% tissue culture infectious dose

*This organism/virus may interfere with this assay.

**The levels of bacteria were determined by limiting dilution, bacterial culture, and colony counting to give cfu/test. Virus concentrations were determined by standard virology methods, Reed-Muench.

Interfering Substances

Several over-the-counter (OTC) products, whole blood, mucin and blood agar were evaluated with the Sofia Strep A+ FIA at the levels tested (Table 8).

Table 8 Interference Testing

Substance	Concentration
Crest Pro-Health Deep Clean Mint Mouth wash (Cetylpyridinium chloride)	24% v/v
Listerine Original Antiseptic Mouth wash (Eucalyptol, Menthol, Methyl salicylate, and Thymol)	24% v/v
Listerine Cool Mint Antiseptic Mouth wash (Eucalyptol, Menthol, Methyl salicylate, and Thymol)	24% v/v
RiteAid Sore throat relief (Benzocaine and Menthol)	24% v/v
Chloraseptic Max Sore Throat (Phenol and Glycerin)	24% v/v
Dimetapp Children's Cold & Cough (Brompheniramine maleate, Dextromethorphan HBr, and Phenylephrine HCI)	24% v/v
RiteAid Children's Cold & Allergy (Brompheniramine maleate and Phenylephrine HCI)	24% v/v
CVS Children's Cold & Cough DM (Brompheniramine maleate, Dextromethorphan HBr, and Phenylephrine HCI)	24% v/v
RiteAid tussin cough&cold mucus relief CF (Dextromethorphan HBr, Guaifenesin, and Phenylephrine HCI)	24% v/v
Robitussin Max Strength Multi-Symptom CF Max (Dextromethorphan HBr, Guaifenesin, and Phenylephrine HCI)	24% v/v
Robitussin Night Time Multi-Symptom Cold CF (Acetaminophen, Diphenhydramine HCl, and Phenylephrine HCI)	24% v/v
Cepacol Sore Throat Cherry (Benzocaine and Menthol)	24% w/v
Halls Triple Soothing Action Cherry (Menthol)	24% w/v
Halls Triple Soothing Action Menthol-lyptus (Menthol)	24% w/v
Ricola Natural Herb Cough Drops (Menthol)	24% w/v
Sucrets Complete Vapor Cherry (Dyclonine Hydrochloride and Menthol)	24% w/v
Chloraseptic Sore Throat Cherry (Phenol and Glycerin)	24% w/v
BreathSavers Spearmint (Cetylpyridinium chloride)	24% w/v

14

Substance	Concentration
Tic Tac freshmints (Eucalyptol, Menthol, Methyl salicylate, and Thymol)	24% w/v
Cheetos, Flaming Hot	12% w/v
Doritos, Nacho Flavor	12% w/v*
Fresh Whole Blood	75 µL/swab**
Mucin	4.3% w/v***
Sheep Blood Agar (5% Sheep Blood)	24% w/v
Horse Blood Agar (5% Horse Blood)	24% w/v

*Nacho Flavor Doritos interfered at 25% w/v

** Fresh Whole Blood interfered at 100 µL/swab

14 100n Whole Blood Intonered at 100 perowas
*** Bovine submaxillary mucin interfered at 28.7 mg/mL

Conclusion:

These studies demonstrated the substantial equivalence of the Sofia Strep A+ FIA with the Sofia to the existing product Sofia Strep A FIA with Sofia (K123793).