Predicate Devices

Reference Devices

AI/ML (Artificial Intelligence / Machine Learning)

No
The document describes a standard RT-PCR assay performed on an automated instrument system. There is no mention of AI or ML in the intended use, device description, or performance studies. The analysis relies on established molecular biology techniques and comparison to predicate devices.

Therapeutic

No.
The device is intended for in vitro qualitative detection and differentiation of specific viral RNA as an aid in diagnosis, not for direct therapy.

Diagnostic

Yes

The "Intended Use / Indications for Use" section explicitly states that the assay is "intended as an aid in the diagnosis of influenza and respiratory syncytial virus infections."

SaMD (Software as a Medical Device)

No

The device is an in vitro diagnostic (IVD) assay that requires specific hardware (Cepheid GeneXpert Instrument Systems and single-use cartridges) to perform sample processing, amplification, and detection. While software is involved in controlling the instrument and generating results, the device is not solely software.

IVD (In Vitro Diagnostic)

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

Here's why:

Intended Use: The "Intended Use / Indications for Use" section explicitly states that the assay is "intended for the in vitro qualitative detection and differentiation of influenza B, and respiratory syncytial virus (RSV) viral RNA." The phrase "in vitro" is a key indicator of an IVD. It also states it is "intended as an aid in the diagnosis," which is a common purpose of IVDs.
Device Description: The "Device Description" section refers to the assay as a "rapid, automated in vitro diagnostic test."
Specimen Type: The assay uses biological specimens (nasopharyngeal swab and nasal aspirate/wash specimens) collected from the human body. This is characteristic of IVDs.
Purpose: The purpose of the assay is to detect specific viral RNA to aid in the diagnosis of infections. This is a diagnostic purpose performed outside of the body.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The Cepheid Xpert Flu/RSV XC Assay is an automated, multiplex real-time, reverse transcriptase polymerase chain reaction (RT-PCR) assay intended for the in vitro qualitative detection and differentiation of influenza B, and respiratory syncytial virus (RSV) viral RNA. The Xpert Flu/RSV XC Assay uses nasopharyngeal swab and nasal aspirate/wash specimens collected from patients with signs and symptoms of respiratory infection. The Xpert Flu/RSV XC Assay is intended as an aid in the diagnosis of influenza and respiratory syncytial virus infections in conjunction with clinical and epidemiological risk factors.

Negative results do not preclude influenza virus or respiratory syncytial virus infection and should not be used as the sole basis for treatment or other patient management decisions.

Performance characteristics for influenza A were established during the 2013-2014 influenza season. When other novel influenza A viruses are emerging, performance characteristics may vary.

If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.

Product codes (comma separated list FDA assigned to the subject device)

OCC, OOI

Device Description

The Xpert Flu/RSV XC Assay is a rapid, automated in vitro diagnostic test for qualitative detection and differentiation of influenza A. influenza B, and respiratory syncytial virus (RSV). The assay is performed on the Cepheid GeneXpert Instrument Systems (GeneXpert Dx systems and GeneXpert Infinity Systems). The GeneXpert Instrument System platform automates and integrates sample purification, nucleic acid amplification, and detection of the target sequence in simple or complex samples using real-time PCR and reverse transcriptase PCR (RT-PCR) assays. The systems require the use of singleuse disposable cartridges (the Xpert Flu/RSV XC cartridges) that hold the PCR reagents and host the PCR process. Because the cartridges are self-contained and specimens never come into contact with working parts of the instrument modules, cross-contamination between samples is minimized.

The Xpert Flu/RSV XC Assay includes reagents for the detection and differentiation of influenza A, influenza B, and RSV viral RNA directly from nasopharyngeal (NP) swab and nasal aspirate/wash (NA/W) specimens collected from patients with signs and symptoms of respiratory infection. A Sample Processing Control (SPC) and a Probe Check Control (PCC) are also included in the cartridge. The SPC is present to control for adequate processing of the target viruses and to monitor the presence of inhibitors in the PCR reaction. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity and dye stability.

The single-use, multi-chambered fluidic cartridges are designed to complete sample preparation and real-time RT-PCR for detection and differentiation of influenza A, influenza B and RSV viral RNA in approximately 60 minutes or less. The GeneXpert Instrument Systems, comprised of the GeneXpert Dx Systems and the GeneXpert Infinity Systems, have 1 to 80 randomly accessible modules, depending upon the instrument, that are each capable of performing separate sample preparation and real-time PCR and RT-PCR tests. Each module contains a syringe drive for dispensing fluids (i.e., the syringe drive activates the plunger that works in concert with the rotary valve in the cartridge to move fluids between chambers), an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and RT-PCR and detection.

Specimens are collected following the user's institution standard procedures for collecting NA/W specimens and NP swab specimens for influenza and RSV testing. The ancillary Cepheid Xpert Nasopharyngeal Sample Collection Kit (Cepheid catalog #SWAB/B-100) or Cepheid's Sample Collection Kit (Cepheid catalog #NASL-100N-100) are required but not provided for use with the assay. Both kits contain the identical viral transport medium and sterile nylon flocked swab. The NA/W specimen or the NP swab specimen is placed into the Xpert viral transport medium and sent to the GeneXpert® testing area for processing. When stored in the transport medium, the NA/W specimen or NP swab specimen is stable for up to 24 hours at 2-30 ℃ or up to seven days at 2-8 ℃. When ready to test the specimen, the user briefly mixes the specimen by inverting the tube five times, transfers the eluted material to the sample chamber in the top of the disposable fluidic cartridge. The user initiates a test from the system user interface and places the cartridge into the GeneXpert instrument platform, which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of RNA. The results are automatically generated at the end of the process in a report that can be viewed and printed.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Nasopharyngeal, nasal

Indicated Patient Age Range

Not Found

Intended User / Care Setting

Operators in moderate and high complexity labs (Laboratories).

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

Not Found

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

Non-Clinical Studies:

Analytical Sensitivity (Limit of Detection): Determined the analytical limit of detection (LoD) using two lots of reagents across three testing days. LoD was established using two influenza A H3N2 strains, two influenza A 2009 H1N1 strains, two influenza B strains, two respiratory syncytial virus A (RSV A) strains, two respiratory syncytial virus B (RSV B) strains, and one influenza A H7N9 strain diluted into a negative pooled clinical matrix. The LoD is defined as the lowest concentration (tissue culture infective dose, TCID50/mL) per sample that can be reproducibly distinguished from negative samples with 95% confidence or the lowest concentration at which 19 of 20 replicates were positive. Each strain was tested in replicates of 20 per concentration of virus. LoD values ranged from 0.3 TCID50/mL for Influenza A/California/7/2009 to 21.0 TCID50/mL for Influenza A/Anhui/1/2013.
Analytical Specificity (Exclusivity): Evaluated by testing a panel of 44 cultures (16 viral, 26 bacterial, 2 yeast strains). Three replicates of all bacterial and yeast strains were tested at concentrations of ≥ 10^6 CFU/mL (except one strain at 10^5 CFU/mL). Three replicates of all viruses were tested at concentrations of ≥ 10^5 TCID50/mL. The analytical specificity was 100%.
Analytical Reactivity (Inclusivity): Evaluated against multiple strains of influenza A H1N1 (seasonal pre-2009), influenza A H1N1 (pandemic 2009), influenza A H3N2 (seasonal), avian influenza A (H5N1, H5N2, H6N2, H7N2, H7N3, H2N2, H7N9, and H9N2), influenza B (from both Victoria and Yamagata lineages), and respiratory syncytial virus subgroups A and B (RSV A and RSV B) at levels near the analytical LoD. A total of 64 strains (54 influenza viruses, 10 RSV strains) were tested with three replicates for each strain. All tested strains showed positive results (POS) for the expected analyte and negative (NEG) for others.
Potentially Interfering Substances: Evaluated substances potentially present in the nasopharynx (e.g., blood, nasal secretions, medications). Negative samples (n=8) and positive samples (n=8, spiked with six influenza and four RSV strains at 2X LoD) were tested per substance. All positive and negative replicates were correctly identified. FluMist vaccine samples were correctly reported as Flu A POSITIVE, FLU B POSITIVE, RSV NEGATIVE.
Carry-Over Contamination: Demonstrated that single-use, self-contained cartridges prevent carry-over contamination. A negative sample was followed by a very high positive sample (approx. 10^6 TCID50/test) for influenza A or RSV A. This was repeated 20 times on two GeneXpert modules (total of 82 runs). All 40 positive samples were correctly reported, and all 42 negative samples were correctly reported.
Fresh vs. Frozen Sample Equivalency Study: Evaluated by testing individual influenza and RSV strains at three concentrations (2X LoD, 5X LoD, 10X LoD) in simulated background matrix. Negative samples consisted of simulated background matrix. 20 replicates for each specimen type and concentration were tested fresh, after one freeze-thaw cycle, and after two freeze-thaw cycles. There was no statistically significant effect in performance between fresh and freeze-thaw samples. All positive and negative replicates were correctly identified.
Linearity: Not applicable (qualitative assay).

Clinical Studies:

Clinical Comparison Study:
- Study Type: Multi-center clinical study conducted at six institutions in the U.S. during the 2013-2014 influenza season. Specimen population was supplemented with frozen prospective and archived specimens due to low prevalence.
- Sample Size:
  - NA/W Specimens: 657 total (581 fresh, prospectively collected; 76 frozen, archived).
  - NP Swab Specimens: 593 total (190 fresh, prospectively collected; 403 frozen, archived).
- Key Results:
  - NA/W Fresh Specimens (n=581):
    - Influenza A: PPA 100% (35/35), NPA 100% (546/546)
    - Influenza B: PPA 99.2% (126/127), NPA 100% (454/454)
    - RSV: PPA 98.5% (128/130), NPA 99.6% (449/451)
  - NA/W Frozen Specimens (n=76):
    - Influenza A: PPA 97.1% (34/35), NPA 100% (41/41)
    - Influenza B: PPA 100% (1/1), NPA 100% (75/75)
    - RSV: PPA 84.6% (11/13), NPA 100% (63/63)
  - NP Swab Fresh Specimens (n=190):
    - Influenza A: PPA 85.7% (6/7), NPA 98.9% (181/183)
    - Influenza B: PPA 100% (3/3), NPA 100% (187/187)
    - RSV: PPA 100% (10/10), NPA 100% (180/180)
  - NP Swab Frozen Specimens (n=403):
    - Influenza A: PPA 99.0% (96/97), NPA 92.8% (284/306)
    - Influenza B: PPA 98.8% (85/86), NPA 100% (317/317)
    - RSV: PPA 90.4% (47/52), NPA 99.1% (348/351)
  - Overall run success rate: 98.6% (1236/1254) on first attempt. Initial indeterminate rate was 1.4%.
Reproducibility Study:
- Study Type: Panel of 10 specimens with varying concentrations tested on 10 different days by two different operators at each of three sites. One lot of cartridges used per site.
- Sample Size: 10 specimens x 1 time/day x 10 days x 2 operators x 3 sites = 60 replicates per panel member.
- Key Results (Total Agreement by Sample):
  - Negative: 100% (60/60)
  - Flu A - High Neg: 70.0% (42/60)
  - Flu A - Low Pos: 96.7% (58/60)
  - Flu A - Mod Pos: 98.3% (59/60)
  - Flu B - High Neg: 76.7% (46/60)
  - Flu B - Low Pos: 90.0% (54/60)
  - Flu B - Mod Pos: 100% (60/60)
  - RSV - High Neg: 66.7% (40/60)
  - RSV - Low Pos: 86.4% (51/59)
  - RSV - Mod Pos: 100% (59/59)
- Precision: Mean Ct values, standard deviation (SD), and coefficient of variation (CV) were reported for between-site, between-day, and between-operator+within-assay variability. Total CV ranged from 0.9% (Negative, SPC) to 8.0% (Flu B - High Neg).
Instrument System Precision:
- Study Type: In-house study comparing GeneXpert Dx and GeneXpert Infinity instrument systems. Panel of 10 specimens with varying concentrations tested on 12 different days by two operators.
- Sample Size: Each operator conducted four runs of each panel specimen per day on each of the two instrument systems (10 specimens x 2 times/day x 12 days x 2 operators x 2 instrument systems = 192 replicates per panel member). Three lots of cartridges used.
- Key Results (Total Agreement by Sample):
  - Negative: 100% (192/192)
  - Flu A - High Neg: 78.7% (151/192)
  - Flu A - Low Pos: 88.0% (169/192)
  - Flu A - Mod Pos: 97.4% (187/192)
  - Flu B - High Neg: 82.3% (158/192)
  - Flu B - Low Pos: 90.6% (174/192)
  - Flu B - Mod Pos: 99.5% (191/192)
  - RSV - High Neg: 84.4% (162/192)
  - RSV - Low Pos: 91.1% (175/192)
  - RSV - Mod Pos: 99.5% (191/192)
- Precision: Mean Ct values, SD, and CV were reported for between-instrument, between-lot, between-day, between-operator, and within-assay variability. Total CV ranged from 1.3% (Negative, SPC) to 6.6% (Flu B - Low Pos).

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

Clinical Comparison Study (PPA and NPA relative to comparator assay, 95% CI):
NA/W Fresh Specimens (n=581):

Flu A: PPA 100% (90.0-100), NPA 100% (99.3-100)
Flu B: PPA 99.2% (95.7-100), NPA 100% (99.2-100)
RSV: PPA 98.5% (94.6-99.8), NPA 99.6% (98.4-99.9)

NA/W Frozen Specimens (n=76):

Flu A: PPA 97.1% (85.1-99.9), NPA 100% (91.4-100)
Flu B: PPA 100% (2.5-100), NPA 100% (95.2-100)
RSV: PPA 84.6% (54.6-98.1), NPA 100% (94.3-100)

NP Swab Fresh Specimens (n=190):

Flu A: PPA 85.7% (42.1-99.6), NPA 98.9% (96.1-99.9)
Flu B: PPA 100% (29.2-100), NPA 100% (98.0-100)
RSV: PPA 100% (69.2-100), NPA 100% (98.0-100)

NP Swab Frozen Specimens (n=403):

Flu A: PPA 99.0% (94.4-100), NPA 92.8% (89.3-95.4)
Flu B: PPA 98.8% (93.7-100), NPA 100% (98.8-100)
RSV: PPA 90.4% (79.0-96.8), NPA 99.1% (97.5-99.8)

Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.

K1109668, K132129, K123191

Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.

K042970

Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).

Not Found

Regulation Number and Section

§ 866.3980 Respiratory viral panel multiplex nucleic acid assay.

(a)
Identification. A respiratory viral panel multiplex nucleic acid assay is a qualitative in vitro diagnostic device intended to simultaneously detect and identify multiple viral nucleic acids extracted from human respiratory specimens or viral culture. The detection and identification of a specific viral nucleic acid from individuals exhibiting signs and symptoms of respiratory infection aids in the diagnosis of respiratory viral infection when used in conjunction with other clinical and laboratory findings. The device is intended for detection and identification of a combination of the following viruses:(1) Influenza A and Influenza B;
(2) Influenza A subtype H1 and Influenza A subtype H3;
(3) Respiratory Syncytial Virus subtype A and Respiratory Syncytial Virus subtype B;
(4) Parainfluenza 1, Parainfluenza 2, and Parainfluenza 3 virus;
(5) Human Metapneumovirus;
(6) Rhinovirus; and
(7) Adenovirus.
(b)
Classification. Class II (special controls). The special controls are:(1) FDA's guidance document entitled “Class II Special Controls Guidance Document: Respiratory Viral Panel Multiplex Nucleic Acid Assay;”
(2) For a device that detects and identifies Human Metapneumovirus, FDA's guidance document entitled “Class II Special Controls Guidance Document: Testing for Human Metapneumovirus (hMPV) Using Nucleic Acid Assays;” and
(3) For a device that detects and differentiates Influenza A subtype H1 and subtype H3, FDA's guidance document entitled “Class II Special Controls Guidance Document: Testing for Detection and Differentiation of Influenza A Virus Subtypes Using Multiplex Nucleic Acid Assays.” See § 866.1(e) for the availability of these guidance documents.

Summary

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Image /page/0/Picture/1 description: The image is a logo for the U.S. Department of Health & Human Services. The logo features a stylized graphic of three human profiles facing right, stacked on top of each other. The profiles are rendered in a dark color, creating a sense of depth and unity. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular fashion around the graphic.

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

Cepheid Scott Campbell, Ph.D., MBA Executive Director, Clinical Affairs 904 Caribbean Drive Sunnyvale CA 94089-1189

November 22, 2014

Re: K142045

Trade/Device Name: Xpert® Flu/RSV XC Assay Regulation Number: 21 CFR 866.3980 Regulation Name: Respiratory viral panel multiplex nucleic acid assay Regulatory Class: II Product Code: OCC, OOI Dated: October 21, 2014 Received: October 22, 2014

Dear Dr. Campbell:

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 (800) 638 2041 or (301) 796-7100 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 (800) 638-2041 or (301) 796-7100 or at its Internet address

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

Sincerely yours,

Uwe Scherf -S for

Sally A. Hojvat Director Division of Microbiology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K142045

Device Name Cepheid Xpert® Flu/RSV XC Assay

Indications for Use (Describe)

The Cepheid Xpert Flu/RSV XC Assay is an automated, multiplex real-time, reverse transcriptase polymerase chain reaction (RT-PCR) assay intended for the in vitro qualitative detection and differentiation of influenza B, and respiratory syncytial virus (RSV) viral RNA. The Xpert Flu/RSV XC Assay uses nasopharyngeal swab and nasal aspirate/wash specimens collected from patients with signs and symptoms of respiratory infection. The Xpert Flu/RSV XC Assay is intended as an aid in the diagnosis of influenza and respiratory syncytial virus infections in conjunction with clinical and epidemiological risk factors.

Negative results do not preclude influenza virus or respiratory syncytial virus infection and should not be used as the sole basis for treatment or other patient management decisions.

Performance characteristics for influenza A were established during the 2013-2014 influenza season. When other novel influenza A viruses are emerging, performance characteristics may vary.

If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.

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

区 Prescription Use (Part 21 CFR 801 Subpart D)
□ Over-The-Counter Use (21 CFR 801 Subpart C)

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5.0 510(k) Summary

As required by 21 CFR Section 807.92(c).

| Submitted by: | Cepheid
904 Caribbean Drive
Sunnyvale, CA 90489
Phone number: (408) 400-8460
Fax number: (847) 510-0539 |
|-------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Contact: | Kerry J. Flom, Ph.D. |
| Date of Preparation: | November 17, 2014 |
| Device: | |
| Trade name: | Xpert® Flu/RSV XC |
| Common name: | Xpert Flu/RSV XC Assay |
| Type of Test: | Automated, multiplex real-time reverse transcription-
polymerase chain reaction (RT-PCR) assay intended for the in
vitro qualitative detection and differentiation of influenza A,
influenza B, and respiratory syncytial virus. |
| Regulation number/
Classification name/
Product code: | 866.3980/Respiratory viral panel multiplex nucleic acid
assay/OCC
866.2570/Instrumentation for clinical multiplex test
systems/OOI |
| Classification | Class II |
| Advisory Panel | Microbiology (83) |
| Prescription Use | Yes |
| Predicate Devices
Assay: | 1) For the detection and differentiation of influenza A,
influenza B, and RSV A/B viral RNA in nasopharyngeal
swab specimens:
Hologic Prodesse® ProFlu™+ Assay (ProFlu+ Assay)
[510(k) #K1109668 and Special 510(k) #K132129]; and,
2) For the detection and differentiation of influenza A and
influenza B viral RNA in nasal aspirate/wash and
nasopharyngeal swab specimens:
Cepheid Xpert Flu [510(k) #K123191]. |
| Predicate Devices
Ancillary Sample
Collection Kit: | Copan Universal Transport Medium (UTM-RT) System
[510(k) #K042970] |

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Device Description:

The Xpert Flu/RSV XC Assay is a rapid, automated in vitro diagnostic test for qualitative detection and differentiation of influenza A. influenza B, and respiratory syncytial virus (RSV). The assay is performed on the Cepheid GeneXpert Instrument Systems (GeneXpert Dx systems and GeneXpert Infinity Systems). The GeneXpert Instrument System platform automates and integrates sample purification, nucleic acid amplification, and detection of the target sequence in simple or complex samples using real-time PCR and reverse transcriptase PCR (RT-PCR) assays. The systems require the use of singleuse disposable cartridges (the Xpert Flu/RSV XC cartridges) that hold the PCR reagents and host the PCR process. Because the cartridges are self-contained and specimens never come into contact with working parts of the instrument modules, cross-contamination between samples is minimized.

The Xpert Flu/RSV XC Assay includes reagents for the detection and differentiation of influenza A, influenza B, and RSV viral RNA directly from nasopharyngeal (NP) swab and nasal aspirate/wash (NA/W) specimens collected from patients with signs and symptoms of respiratory infection. A Sample Processing Control (SPC) and a Probe Check Control (PCC) are also included in the cartridge. The SPC is present to control for adequate processing of the target viruses and to monitor the presence of inhibitors in the PCR reaction. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity and dye stability.

The single-use, multi-chambered fluidic cartridges are designed to complete sample preparation and real-time RT-PCR for detection and differentiation of influenza A, influenza B and RSV viral RNA in approximately 60 minutes or less. The GeneXpert Instrument Systems, comprised of the GeneXpert Dx Systems and the GeneXpert Infinity Systems, have 1 to 80 randomly accessible modules, depending upon the instrument, that are each capable of performing separate sample preparation and real-time PCR and RT-PCR tests. Each module contains a syringe drive for dispensing fluids (i.e., the syringe drive activates the plunger that works in concert with the rotary valve in the cartridge to move fluids between chambers), an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and RT-PCR and detection.

Specimens are collected following the user's institution standard procedures for collecting NA/W specimens and NP swab specimens for influenza and RSV testing. The ancillary Cepheid Xpert Nasopharyngeal Sample Collection Kit (Cepheid catalog #SWAB/B-100) or Cepheid's Sample Collection Kit (Cepheid catalog #NASL-100N-100) are required but not provided for use with the assay. Both kits contain the identical viral transport medium and sterile nylon flocked swab. The NA/W specimen or the NP swab specimen is placed into the Xpert viral transport medium and sent to the GeneXpert® testing area for processing. When stored in the transport medium, the NA/W specimen or NP swab specimen is stable for up to 24 hours at 2-30 ℃ or up to seven days at 2-8 ℃. When ready to test the specimen, the user briefly mixes the specimen by inverting the tube five times, transfers the eluted material to the sample chamber in the

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top of the disposable fluidic cartridge. The user initiates a test from the system user interface and places the cartridge into the GeneXpert instrument platform, which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of RNA. The results are automatically generated at the end of the process in a report that can be viewed and printed.

Device Intended Use:

The Cepheid Xpert Flu/RSV XC Assay is an automated, multiplex real-time, reverse transcriptase polymerase chain reaction (RT-PCR) assay intended for the in vitro qualitative detection and differentiation of influenza B, and respiratory syncytial virus (RSV) viral RNA. The Xpert Flu/RSV XC Assay uses nasopharyngeal swab and nasal aspirate/wash specimens collected from patients with signs and symptoms of respiratory infection. The Xpert Flu/RSV XC Assay is intended as an aid in the diagnosis of influenza and respiratory syncytial virus infections in conjunction with clinical and epidemiological risk factors.

Negative results do not preclude influenza virus or respiratory syncytial virus infection and should not be used as the sole basis for treatment or other patient management decisions.

Performance characteristics for influenza A were established during the 2013-2014 influenza season. When other novel influenza A viruses are emerging, performance characteristics may vary.

If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.

Ancillary Specimen Collection Kit

Xpert® Nasopharyngeal Sample Collection Kit

The Xpert Nasopharyngeal Sample Collection Kit is designed to collect, preserve and transport nasopharyngeal swab specimens and to preserve and transport nasal aspirate/wash specimens from patients with signs and symptoms of respiratory infection prior to analysis with the Xpert Flu Assay or the Xpert Flu/RSV XC Assay.

The Xpert Nasopharyngeal Sample Collection Kit has only been cleared for use with the Xpert Flu Assay and Xpert Flu/RSV XC Assays.

6

Substantial Equivalence:

The Xpert Flu/RSV XC Assay is substantially equivalent to the ProFlu+ Assay [510(k) # K110968 and #K132139] and to the current Cepheid Xpert Flu Assay (510(k) #K123191). The ProFlu+ Assay and the Xpert Flu/RSV XC Assay detect influenza A, influenza B. and RSV A/B from NP swab specimens. The Xpert Flu Assay detects influenza A and B from both NP swab specimens and NA/W specimens, and the Xpert Flu/RSV XC Assay detects influenza A. influenza B. and RSV from both NP swab specimens and NA/W specimens. All three assays utilize the same technology by determining the presence of the target organisms through real-time RT-PCR amplification and fluorogenic target-specific hybridization detection. A multi-center clinical study was conducted to determine the performance characteristics of the device relative to the primary predicate device, the ProFlu+ Assay, which was validated for use with NA/W specimens, and FDA cleared for NP swab specimens. Discordant results between the Xpert Flu/RSV XC Assay and the ProFlu+ Assay were analyzed by sequencing using primers different from those used in the Xpert Flu/RSV XC Assay. The study results showed the Xpert Flu/RSV XC Assay is acceptable for its intended use and is substantially equivalent to the predicate devices.

Table 5-1 shows the similarities and differences between the Xpert Flu/RSV XC Assav and the predicate assays.

Similarities
	Device	Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid
Xpert Flu	Hologic Prodesse
ProFlu+ Assay
510(k)
Number	#K142045	#K123191	#K110968 and
#K132129 (special)
Regulation	866.3980	Same	Same
Product
Code	OCC, OOI	OQW, OCC, OOI	OCC, OOI
Device
Class	II	Same	Same
Technology
Principle of
Operation	Multiplex real time RT-
PCR	Same	Same
Similarities
	Device	Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid
Xpert Flu	Hologic Prodesse
ProFlu+ Assay
Intended
Use	The Cepheid Xpert
Flu/RSV XC Assay,
performed on the
GeneXpert Instrument
Systems, is an
automated, multiplex
real-time, reverse
transcriptase polymerase
chain reaction (RT-PCR
assay intended for the in
vitro qualitative detection
and differentiation of
influenza A, influenza B,
and respiratory syncytial
virus (RSV) viral RNA.
The Xpert Flu/RSV XC
Assay uses nasopharyn-
geal swab and nasal
aspirate/wash specimens
collected from patients
with signs and symptoms
of respiratory infection in
conjunction with clinical
and epidemiological risk
factors. The Xpert
Flu/RSV XC Assay is
intended as an aid in the
diagnosis of influenza
and respiratory syncytial
virus.	The Cepheid Xpert Flu
Assay,
performed on the
GeneXpert Instrument
Systems, is an
automated, multiplex
real-time RT-PCR
assay intended for the
in vitro qualitative
detection and
differentiation of
influenza A, influenza
B and 2009 H1N1
influenza viral RNA.
The Xpert Flu Assay
uses nasal
aspirates/washes and
nasopharyngeal swab
specimens collected
from patients with
signs and symptoms of
respiratory infection in
conjunction with
clinical and
epidemiological risk
factors. The Xpert Flu
Assay is intended as an
aid in the diagnosis of
influenza.	The ProFlu™+ Assay
is a multiplex Real-
Time PCR (RT-PCR)
in vitro
diagnostic test for the
rapid and qualitative
detection and
discrimination of
Influenza A Virus,
Influenza B Virus, and
Respiratory Syncytial
Virus (RSV) nucleic
acids isolated and
purified from
nasopharyngeal (NP)
swab specimens
obtained from
symptomatic patients.
This test is intended for
use to aid in the
differential diagnosis of
Influenza A, Influenza
B and RSV viral
infections in humans
and is not intended to
detect Influenza C.
	Negative results do not
preclude influenza virus
or respiratory syncytial
virus infection and
should not be used as the
sole basis for treatment
or other patient
management decisions.	Negative results do not
preclude influenza
virus infection and
should not be used as
the sole basis for
treatment or other
patient management
decisions.	Negative results do not
preclude influenza or
RSV virus infection
and should not be used
as the sole basis for
treatment or other
management decisions.
Conversely, positive
results do not rule-out
bacterial infection or
Similarities
	Device	Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid
Xpert Flu	Hologic Prodesse
ProFlu+ Assay
			co-infection with other
viruses. The agent
detected may not be the
definite cause of
disease. The use of
additional laboratory
testing and clinical
presentation must be
considered in order to
obtain the final
diagnosis of respiratory
viral infection.
	Performance
characteristics for
influenza A were
established during the
2013-2014 influenza
season. When other
novel influenza A viruses
are emerging,
performance
characteristics may vary.	Performance
characteristics for
influenza A were
established during the
2009-2010 influenza
season when 2009
H1N1 influenza was
the predominant
influenza A virus in
circulation.
Performance
characteristics for
influenza A were
confirmed when
influenza A/H3 and
influenza A/2009
H1N1 were the
predominant influenza
A viruses in circulation
(2009-2010, 2010-2011
and 2011-2012). When
other influenza A
viruses are emerging,
performance
characteristics may
vary.	Performance
characteristics for
Influenza A Virus were
established when
Influenza A/H3 and
A/H1 were the
predominant Influenza
A viruses in circulation
(2006 - 2007
respiratory season).
Performance
characteristics for
Influenza A were
confirmed when
Influenza A/H1,
Influenza A/H3, and
Influenza A/2009
H1N1 were the
predominant Influenza
A viruses in circulation
(2008 and 2009). When
other Influenza A
viruses are emerging,
performance
characteristics may
vary.
Similarities
	Device	Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid
Xpert Flu	Hologic Prodesse
ProFlu+ Assay
	If infection with a novel
influenza A virus is
suspected based on
current clinical and
epidemiological
screening criteria
recommended by public
health authorities,
specimens should be
collected with
appropriate infection
control precautions for
novel virulent influenza
viruses and sent to state
or local health
department for testing.
Viral culture should not
be attempted in these
cases unless a BSL 3+
facility is available to
receive and culture
specimens.	If infection with a
novel influenza A virus
is suspected based on
current clinical and
epidemiological
screening criteria
recommended by
public health
authorities, specimens
should be collected
with appropriate
infection control
precautions for novel
virulent influenza
viruses and sent to state
or local health
department for testing.
Viral culture should not
be attempted in these
cases unless a BSL 3+
facility is available to
receive and culture
specimens.	If infection with a
novel Influenza A virus
is suspected based on
current clinical and
epidemiological
screening criteria
recommended by
public health
authorities, specimens
should be collected
with appropriate
infection control
precautions for novel
virulent Influenza
viruses and sent to state
or local health
department for testing.
Viral culture should not
be attempted in these
cases unless a BSL 3+
facility is available to
receive and culture
specimens.
Indication
for Use	Patients with signs and
symptoms of respiratory
infection in conjunction
with clinical and
epidemiological risk
factors	Same as Xpert
Flu/RSV XC Assay	Same - symptomatic
patients
Assay
Targets	Influenza A Virus,
Influenza B Virus, and
RSV viral RNA	Influenza A, influenza
B, and influenza A,
subtype 2009 H1N1	Same as Xpert
Flu/RSV XC Assay
Specimen
Types	Nasal aspirate/wash
(NA/W) specimens and
Nasopharyngeal (NP)
swab specimens	Same as Xpert
Flu/RSV XC Assay	Nasopharyngeal (NP)
swab specimens; use of
ProFlu+ Assay with
NA/W specimens was
validated.
Similarities
	Device	Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid
Xpert Flu	Hologic Prodesse
ProFlu+ Assay
Nucleic
Acid
Extraction	Yes	Same	Same
Extraction
Methods	Sample preparation
integrated in GeneXpert
Cartridge and GeneXpert
Instrumentation System	Same as Xpert
Flu/RSV XC Assay	Extraction and
purification with Roche
MagNA Pure LC
System or bioMérieux
NucliSENS easyMAG
System
Assay
Results	Qualitative	Same	Same
Instrument
System	Cepheid GeneXpert
Instrument Systems;
same Cepheid I-core
technology	Same as Xpert
Flu/RSV XC Assay	Cepheid SmartCycler II
System; same Cepheid
I-core technology
Assay
Controls	Encapsulated (armored)
RNA pseudovirus as a
sample processing
control.
Available but not
provided are inactivated
virus controls for
influenza A/B and RSV
as external positive
controls, and Coxsackie
virus as an external
negative control.	Same as Xpert
Flu/RSV XC Assay	Internal RNA control.
Required and provided:
influenza A, influenza
B, RSV A, RSV B
positive RNA transcript
controls
Time to
obtain test
results	Approximately 60
minutes or less for
sample preparation and
real-time RT-PCR.	75 minutes for sample
preparation and real-
time RT-PCR	Approximately 4 hours
for sample preparation
and real-time RT-PCR
Primers
and probes	Primers and probes to
detect the presence of
nucleic acid sequences of
influenza A, influenza B,
and RSV	Primers and probes to
detect the presence of
nucleic acid sequences
of influenza A,
influenza B, and
influenza, subtype
H1N1	Same as Xpert
Flu/RSV XC Assay
Similarities
	Device	Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid Xpert Flu
Hologic Prodesse ProFlu+ Assay
Laboratory Users	Operators in moderate and high complexity labs	Same as Xpert Flu/RSV XC Assay; categorized as CLIA Moderate Complexity.
CLIA High Complexity

Table 5-1: Comparison of Similarities and Differences of the Xpert Flu/RSV XC Assay with the Predicate Devices

7

8

9

10

11

| Primary Differences

(Differences are also Captured in the Similarities Table above)
Item	New Device
Cepheid Xpert Flu/RSV XC	Predicate Devices
		Current Cepheid
Xpert Flu
		Prodesse® ProFluTM+
Assay
Intended
Use
Differences	Detects and differentiates
between influenza A,
influenza B, and RSV
viral RNA.	Detects and
differentiates between
influenza A, influenza
B, and 2009 H1N1
influenza viral RNA.
Does not detect RSV
viral RNA.
Specimen
Types	Nasal aspirate/wash
(NA/W) specimens and
Nasopharyngeal (NP)
swab specimens	Same as Xpert
Flu/RSV XC Assay
		Nasopharyngeal (NP)
swab specimens; not
FDA cleared for NA/W
specimens, but
specimen type was
validated for use in the
clinical study.
Test
Cartridge	Disposable single-use,
multi-chambered fluidic
cartridge with all
reagents contained in the
cartridge.	Disposable single-use,
multi-chambered
fluidic cartridge. One
reagent must be added
to the cartridge.
		Disposable single-use
PCR tube. All reagents
and controls must be
added to the PCR tube.
Instrument
System	Cepheid GeneXpert Dx
Systems and GeneXpert
Infinity Systems	Same as Xpert
Flu/RSV XC Assay
		Cepheid SmartCycler
Primary Differences
(Differences are also Captured in the Similarities Table above)
	New Device		Predicate Devices
Item	Cepheid Xpert Flu/RSV
XC	Current Cepheid
Xpert Flu	Prodesse® ProFlu™+
Assay
Sample
Preparation	Self-contained and
automated after mixed
specimen is added to
cartridge. All other
reagents are contained in
the cartridge.	Self-contained and
automated after mixed
specimen and one
single-dose reagent are
added to cartridge.	Manual
Primers
and probes
for
influenza
A,
influenza
B, and
influenza A
subtype
H1N1	Primers and probes to
detect the presence of
nucleic acid sequences of
influenza A, influenza B,
and RSV A/B. The
Xpert Flu/RSV Assay
contains additional RNA
segments in order to
protect the assay
sensitivity from
mutations in the
influenza genome due to
antigenic drifts and shifts
as compared to the Xpert
Flu Assay.	Primers and probes to
detect the presence of
nucleic acid sequences
of influenza A,
influenza B, and
influenza, subtype
H1N1. The current
Xpert Flu Assay does
not detect RSV	Primers and probes to
detect the presence of
nucleic acid sequences
of influenza A,
influenza B, and RSV
A/B.
Target
Sequence	Influenza A: Matrix
protein (MP),
Polymerase (PB 2 and
PA), and Hemagglutinin
(HA for H7N9)

Influenza B: Matrix
protein (MP) and Non-
structural proteins (NS 1
and NS 2)

RSV A and RSV B:
Nucleocapsid protein | Influenza A: Matrix
protein and
Hemagglutinin (HA for
H1N1)

Influenza B:
Hemagglutinin (HA) | Influenza A: Matrix
protein (MP)

Influenza B: Non-
structural protein (NS 1
and NS 2)

12

13

The Xpert Flu/RSV XC Assay has the same intended use as the primary predicate device and the same technological characteristics as both predicate devices. The clinical study demonstrates that the Xpert Flu/RSV XC Assay is acceptable for its intended use and is substantially equivalent to the predicate devices.

The predicate device for the ancillary specimen collection kit, the Xpert® Nasopharyngeal Sample Collection Kit, is the Copan Universal Transport Medium (UTM-RT) System, [510(k) # K042970]. The similarities and differences are shown in Table 5-2.

14

Similarities
Item	Device	Predicate
Intended Use	The Xpert® Nasopharyngeal
Sample Collection Kit is
designed to collect, preserve and
transport nasopharyngeal swab
specimens and to preserve and
transport nasal aspirate/wash
specimens from patients with
signs and symptoms of
respiratory infection prior to
analysis with the Xpert Flu
Assay or the Xpert Flu/RSV XC
Assay.
The Xpert® Nasopharyngeal
Sample Collection Kit has only
been cleared for use with the
Xpert Flu and Xpert Flu/RSV
XC Assays.	Copan Universal Transport
Medium (UTM-RT) System is
intended for the collection and
transport of clinical specimens
containing viruses, chlamydiae,
mycoplasma or ureaplasma
from the collection site to the
testing laboratory. UTM-RT
can be processed using standard
clinical laboratory operating
procedures for viral, chlamydial,
mycoplasma and ureaplasma
culture.
Single-use Device	Yes	Same
Medium Formulation	Hank's Balanced Salt Solution
Bovine Serum Albumin
L-cysteine
Gelatin
Sucrose
L-glutamic acid
HEPES buffer
Vancomycin
Amphotericin B
Colistin
Phenol red	Same
pH	$7.3 \pm 0.2$	Same
Storage Temperature	2 - 25°C (refrigerated
and room temperature)	Same
Volume	3 ml	1.5 ml; 3 ml; or 10 ml
Glass Beads	3 x 3 mm	Same

Table 5-2: Comparison of Similarities and Differences of the Xpert Nasopharyngeal Sample Collection Kit with the Predicate Device

15

| Container | Plastic (medical-grade
polypropylene) | Plastic |
|-------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Product Configuration | Medium Tube in Kit with
individually-wrapped sterile
swab. | Medium Tubes;
Kit with Medium Tubes and
Swab Options |
| Differences | | |
| Item | Device | Predicate |
| Intended Use
(differences) | For collection, preservation
and transport of
nasopharyngeal swab
specimens and to preserve and
transport nasal aspirate/wash
specimens containing viruses
from patients with signs and
symptoms of respiratory
infection prior to analysis
with the Xpert Flu and Xpert
Flu/RSV XC Assay. | For collection, transport (and
preservation of viability) of
swab collected clinical
specimens containing viruses,
chlamydiae, mycoplasma or
ureaplasma. UTM-RT can be
processed using standard
clinical laboratory operating
procedures for viral, chlamydial,
mycoplasma and ureaplasma
culture. |
| Swab | Nylon flocked (same
collection swab as used with
the current Xpert Flu Assay). | Polyester |

Both devices have the same general intended use and use the same technology to collect, store and transport clinical specimens, including viruses, to the laboratory for further testing. The prospective component of the multi-center clinical study of the Xpert Flu/RSV XC was conducted using Copan-manufactured UTM-RT and sterile nylon flocked swab demonstrating that the Xpert Nasopharyngeal Sample Collection Kit is acceptable for its intended use and substantially equivalent to the predicate device.

Non-Clinical Studies:

Analytical Sensitivity (Limit of Detection)

Studies were performed to determine the analytical limit of detection (LoD) of the Xpert Flu/RSV XC Assay with two lots of reagents across three testing days. The higher LoD observed per strain and per lot was selected for verification. Verification of the estimated LoD claim was performed on one reagent lot across a minimum of three testing days. LoD was established using two influenza A H3N2 strains, two influenza A 2009 H1N1 strains, two influenza B strains, two respiratory syncytial virus A (RSV A) strains, two respiratory syncytial virus B (RSV B) strains, and one influenza A H7N9 strain diluted into a negative pooled clinical matrix. The LoD is

16

defined as the lowest concentration (tissue culture infective dose, TCID50/mL) per sample that can be reproducibly distinguished from negative samples with 95% confidence or the lowest concentration at which 19 of 20 replicates were positive. Each strain was tested in replicates of 20 per concentration of virus.

The LoD was determined empirically as the first concentration that had 19/20 or 20/20 positive results. The LoD point values for each strain tested are summarized in 5-3 to Table 5-8.

| Strain ID | Confirmed LOD
(TCID50/mL)
(at least 19/20 positive) |
|-------------------------------|-----------------------------------------------------------|
| Influenza A/California/7/2009 | 0.3 (20/20) |
| Influenza A/Florida/27/2011 | 16 (19/20) |

Table 5-3: Confirmed LoD (TCID50/mL): Influenza A 2009 H1N1

Table 5-4: Confirmed LoD (TCID50/mL): Influenza A H3N2

| Strain ID | Confirmed LOD
(TCID50/mL)
(at least 19/20 positive) |
|-------------------------------|-----------------------------------------------------------|
| Influenza A/Perth/16/2009 | 0.3 (20/20) |
| Influenza A/Victoria/361/2011 | 0.8 (20/20) |

Table 5-5: Confirmed LoD (TCID50/mL): Influenza B

| Strain ID | Confirmed LOD
(TCID50/mL)
(at least 19/20 positive) |
|----------------------------------|-----------------------------------------------------------|
| Influenza B/Massachusetts/2/2012 | 0.5(20/20) |
| Influenza B/Wisconsin/01/2011 | 0.6 (20/20) |

Table 5-6: Confirmed LoD (TCID56/mL): Respiratory Syncytial Virus A

| Strain ID | Confirmed LOD
(TCID50/mL)
(at least 19/20 positive) |
|----------------------|-----------------------------------------------------------|
| RSV A/2/Australia/61 | 1.2 (20/20) |
| RSV A/Long/MD/56 | 1.0 (19/20) |

17

| Strain ID | Confirmed LOD
(TCID50/mL)
(at least 19/20 positive) |
|-----------------------------|-----------------------------------------------------------|
| RSV B/Washington/18537/62 | 1.8 (20/20) |
| RSV B/9320/Massachusetts/77 | 2.0 (19/20) |

Table 5-7: Confirmed LoD (TCID50/mL): Respiratory Syncytial Virus B

Table 5-8: Confirmed LoD (TCID50/mL): Influenza A H7N9

| Strain ID | Confirmed LOD
(TCID50/mL)
(at least 19/20 positive) |
|--------------------------|-----------------------------------------------------------|
| Influenza A/Anhui/1/2013 | 21.0 (19/20) |

Analytical Specificity (Exclusivity)

The analytical specificity of the Xpert Flu/RSV XC Assay was evaluated by testing a panel of 44 cultures consisting of 16 viral, 26 bacterial, and two yeast strains representing common respiratory pathogens or those potentially encountered in the nasopharynx. Three replicates of all bacterial and yeast strains were tested at concentrations of ≥ 106 CFU/mL with the exception of one strain which was tested at 10° CFU/mL (Chlamydia pneumoniae). Three replicates of all viruses were tested at concentrations of ≥ 105 TCID50/mL. The analytical specificity was 100%. Results are shown in Table 5-9.

18

Organism	Concentration	Influenza A	Influenza B	RSV
No Template Control		NEG	NEG	NEG
Adenovirus Type 1	1.12x107 TCID50/mL	NEG	NEG	NEG
Adenovirus Type 7	1.87x105 TCID50/mL	NEG	NEG	NEG
Human coronavirus OC43	2.85x105 TCID50/mL	NEG	NEG	NEG
Human coronavirus 229E	1x105 TCID50/mL	NEG	NEG	NEG
Cytomegalovirus	7.24x105 TCID50/mL	NEG	NEG	NEG
Echovirus	3.31x107 TCID50/mL	NEG	NEG	NEG
Enterovirus	1x105 TCID50/mL	NEG	NEG	NEG
Epstein Barr Virus	7.16x107 TCID50/mL	NEG	NEG	NEG
HSV	8.9x106 TCID50/mL	NEG	NEG	NEG
Measles	6.3x105 TCID50/mL	NEG	NEG	NEG
Human metapneumovirus	3.8x105 TCID50/mL	NEG	NEG	NEG
Mumps virus	6.31x106 TCID50/mL	NEG	NEG	NEG
Human parainfluenza Type 1	1.15x106 TCID50/mL	NEG	NEG	NEG
Human parainfluenza Type 2	1x105 TCID50/mL	NEG	NEG	NEG
Human parainfluenza Type 3	3.55x107 TCID50/mL	NEG	NEG	NEG
Rhinovirus Type 1A	1.26x105 TCID50/mL	NEG	NEG	NEG
Acinetobacter baumannii	>1x106 CFU/mL	NEG	NEG	NEG
Burkholderia cepacia	>1x106 CFU/mL	NEG	NEG	NEG
Candida albicans	>1x106 CFU/mL	NEG	NEG	NEG
Candida parapsilosis	>1x106 CFU/mL	NEG	NEG	NEG
Bordetella pertussis	1x108 CFU/mL	NEG	NEG	NEG
Organism	Concentration	Influenza A	Influenza B	RSV
Chlamydia pneumoniae	3.16x105 CFU/mL	NEG	NEG	NEG
Citrobacter freundii	>1x106 CFU/mL	NEG	NEG	NEG
Corynebacterium sp.	>1x106 CFU/mL	NEG	NEG	NEG
Escherichia coli	>1x106 CFU/mL	NEG	NEG	NEG
Enterococcus faecalis	>1x106 CFU/mL	NEG	NEG	NEG
Hemophilus influenzae	1x106 CFU/mL	NEG	NEG	NEG
Lactobacillus sp.	1x106 CFU/mL	NEG	NEG	NEG
Legionella spp.	1x108 CFU/mL	NEG	NEG	NEG
Moraxella catarrhalis	>1x106 CFU/mL	NEG	NEG	NEG
Mycobacterium tuberculosis
(avirulent)	1.15x106 CFU/mL	NEG	NEG	NEG
Mycoplasma pneumoniae	1x107 CFU/mL	NEG	NEG	NEG
Neisseria meningitides	>1x106 CFU/mL	NEG	NEG	NEG
Neisseria mucosa	>1x106 CFU/mL	NEG	NEG	NEG
Propionibacterium acnes	>1x106 CFU/mL	NEG	NEG	NEG
Pseudomonas aeruginosa	>1x106 CFU/mL	NEG	NEG	NEG
Staphylococcus aureus
(protein A producer)	>1x106 CFU/mL	NEG	NEG	NEG
Staphylococcus epidermidis	>1x106 CFU/mL	NEG	NEG	NEG
Staphylococcus haemolyticus	>1x106 CFU/mL	NEG	NEG	NEG
Streptococcus agalactiae	>1x106 CFU/mL	NEG	NEG	NEG
Streptococcus pneumoniae	>1x106 CFU/mL	NEG	NEG	NEG
Streptococcus pyogenes	>1x106 CFU/mL	NEG	NEG	NEG
Streptococcus salivarius	>1x106 CFU/mL	NEG	NEG	NEG
Streptococcus sanguinis	>1x106 CFU/mL	NEG	NEG	NEG

Table 5-9: Analytical Specificity of Xpert Flu/RSV XC Assay

19

20

Analytical Reactivity (Inclusivity)

The analytical reactivity of the Xpert Flu/RSV XC Assay was evaluated against multiple strains of influenza A H1N1 (seasonal pre-2009), influenza A H1N1 (pandemic 2009), influenza A H3N2 (seasonal), avian influenza A (H5N1, H5N2, H6N2, H7N2, H7N3, H2N2, H7N9, and H9N2), influenza B (representing strains from both Victoria and Yamagata lineages), and respiratory syncytial virus subgroups A and B (RSV A and RSV B) at levels near the analytical LoD. A total of 64 strains including 54 influenza viruses and 10 RSV strains were tested in this study with the Xpert Flu/RSV XC Assay.

Three replicates were tested for each strain. Results are shown in Table 5-10.

Virus	Strain	Concentration	Result
			Flu
A	Flu
B	RSV
No Template Control			NEG	NEG	NEG
	A/swine/Iowa/15/30	32.0 TCID50/mL	POS	NEG	NEG
	A/WS/33	32.0 TCID50/mL	POS	NEG	NEG
	A/PR/8/34	32.0 TCID50/mL	POS	NEG	NEG
	A/Mal/302/54	32.0 TCID50/mL	POS	NEG	NEG
Influenza A
H1N1 (pre-

| A/Denver/1/57 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/New Jersey/8/76 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/New Caledonia/20/1999 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/New York/55/2004 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/Soloman Island/3/2006 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/Taiwan/42/06 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/Brisbane/59/2007 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/California/7/2009 | 32.0 TCID50/mL | POS | NEG | NEG |
| Influenza A
H1N1
(pdm2009) | A/swine/NY/02/2009 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/Florida/27/2011 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/Colorado/14/2012 | 32.0 TCID50/mL | POS | NEG | NEG |
| | A/Washington/24/2012 | 80.0 a TCID50/mL | POS | NEG | NEG |
| | A/Aichi/2/68 | 1.6 TCID50/mL | POS | NEG | NEG |
| Influenza A
H3N2
(Seasonal) | A/HongKong/8/68 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Port Chalmers/1/73 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Hawaii/15/2001 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Wisconsin/67/05 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Brisbane/10/2007 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Perth/16/2009 | 1.6 TCID50/mL | POS | NEG | NEG |
| | Strain | Concentration | Result | | |
| Virus | | | Flu
A | Flu
B | RSV |
| | A/Minnesota/11/2010 (H3N2)v | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Indiana/08/2011 (H3N2)v | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Victoria/361/2011 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/Texas/50/2012 | 1.6 TCID50/mL | POS | NEG | NEG |
| | A/duck/Hunan/795/2002 (H5N1) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/chicken/Hubei/327/2004 (H5N1) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/Anhui/01/2005 (H5N1) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/Japanese white
eye/HongKong/1038/2006 (H5N1) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/mallard/WI/34/75 (H5N2) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/chicken/CA431/00 (H6N2) | ≤ 1pg/μLb | POS | NEG | NEG |
| Avian
influenza A | A/duck/LTC-10-82743/1943 (H7N2) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/chicken/NJ/15086-3/94 (H7N3) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/Anhui/1/2013 (H7N9) | N/Ac | POS | NEG | NEG |
| | A/Shanghai/1/2013 (H7N9) | N/Ac | POS | NEG | NEG |
| | A/chicken/Korea/38349-p96323/ 1996
(H9N2) | ≤ 1pg/μLb | POS | NEG | NEG |
| | A/Mallard/NY/6750/78 (H2N2) | ≤ 1pg/μLb | POS | NEG | NEG |
| | B/Lee/40 | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Allen/45 | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/GL/1739/54 | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Maryland/1/59 | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Panama/45/90d | 3.0 TCID50/mLe | NEG | POS | NEG |
| Influenza B | B/Florida/07/2004f | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Florida/02/06d | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Florida/04/06f | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Wisconsin/01/2011d | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Massachusetts/2/2012f | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Hong Kong/5/72 | 1.2 TCID50/mL | NEG | POS | NEG |
| Virus | Strain | Concentration | Result | | |
| | | | Flu
A | Flu
B | RSV |
| | B/Wisconsin/01/2010f | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Malaysia/2506/04d | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Taiwan/2/62 | 1.2 TCID50/mL | NEG | POS | NEG |
| | B/Brisbane/60/2008d | 1.2 TCID50/mL | NEG | POS | NEG |
| RSV A | RSV-A/Long/MD/56 | 2.4 TCID50/mL | NEG | NEG | POS |
| | RSV-A/2/Australia/61 | 2.4 TCID50/mL | NEG | NEG | POS |
| | RSV-A/NY (Clinical unknown) | 2.4 TCID50/mL | NEG | NEG | POS |
| | RSV-A/WI/629-8-2/2007 | 2.4 TCID50/mL | NEG | NEG | POS |
| | RSV-A/WI/629-11-1/2008 | 2.4 TCID50/mL | NEG | NEG | POS |
| RSV B | RSV-B/Wash/18537/62 | 4.0 TCID50/mL | NEG | NEG | POS |
| | RSV-B/9320/MA/77 | 4.0 TCID50/mL | NEG | NEG | POS |
| | RSV-B/WV14617/85 | 4.0 TCID50/mL | NEG | NEG | POS |
| | RSV-B/CH93(18)-18 | 20.0 TCID50/mLg | NEG | NEG | POS |
| | RSV-B/WI/629-5B/0607 | 4.0 TCID50/mL | NEG | NEG | POS |

Table 5-10: Analytical Reactivity (Inclusivity) of Xpert Flu/RSV XC Assay

21

22

4Influenza A/Washington/24/2012 was tested at 5X LoD (80.0 TCIDsy/mL) to obtain 3 of 3 Flu A POSITIVE result calls.

"Purified viral RNA in simulated background matrix was used for avian influenza A viruses due to biosafety regulations.

SInactivated avian influenza A (H7N9) viruses without viral titer was diluted 100,000 fold in simulated background matrix and tested due to biosafety regulations.

dKnown Victoria lineage.

Sinfluenza B/Panama/45/90 was tested at 5X LoD (3.0 TCID30mL) to obtain 3/3 Flu B POSITIVE result calls. 1Known Yamagata lineage.

6RSV-B/CH93(18)-18 was tested at 10X LoD (20.0 TCID50/mL) to obtain 3/3 RSV POSITIVE result calls.

Although this test has been shown to detect the novel avian influenza A (H7N9) cultured material, the performance characteristics of this device with clinical specimens that are positive for the novel avian influenza A (H7N9) virus have not been established. The Xpert Flu/RSV XC Assay can distinguish between influenza A and B viruses, but it cannot differentiate influenza subtypes.

Potentially Interfering Substances

In a non-clinical study, potentially interfering substances that may be present in the nasopharynx were evaluated directly relative to the performance of the Xpert Flu/RSV XC Assay. Potentially interfering substances in the nasopharynx may include, but are not limited to: blood, nasal secretions or mucus, and nasal and throat medications used to relieve congestion, nasal dryness, irritation, or asthma and allergy symptoms, as well as antibiotics and antivirals. Negative samples (n = 8) were tested per each substance

23

to determine the effect on the performance of the sample processing control (SPC). Positive samples (n = 8) were tested per substance with six influenza (four influenza A and two influenza B) and four RSV (two RSV A and two RSV B) strains spiked at 2X the analytical LoD determined for each strain. All results were compared to positive and negative Universal Transport Medium (UTM) controls.

These evaluated substances are listed in Table 5-11 with active ingredients and concentrations tested shown. There was no assay interference in the presence of the substances at the concentrations tested in this study. All positive and negative replicates were correctly identified using the Xpert Flu/RSV XC Assay.

FluMist vaccine samples were correctly reported as Flu A POSITIVE: FLU B POSITIVE; RSV NEGATIVE as expected. Samples containing FluMist may cause false positive results. This is addressed in Section 17, Limitations.

| Substance/Class | Description/Active
Ingredient | Concentration
Tested |
|------------------------------------------------------|---------------------------------------------------------------------|-------------------------------------------------|
| Beta-adrenergic
bronchodilator | Albuterol Sulfate | 0.83 mg/mL
(equivalent to
1 dose per day) |
| Blood | Blood (Human) | 2% (v/v) |
| BD™ Universal
Viral Transport
System | Transport Media | 100% (v/v) |
| Remel M4® | Transport Media | 100% (v/v) |
| Remel M4RT® | Transport Media | 100% (v/v) |
| Remel M5® | Transport Media | 100% (v/v) |
| Throat lozenges,
oral anesthetic
and analgesic | Benzocaine, Menthol | 1.7 mg/mL |
| Mucin | Purified Mucin protein
(Bovine or porcine
submaxillary gland) | 2.5% (w/v) |
| Antibiotic, nasal
ointment | Mupirocin | 10 mg/mL |
| Saline Nasal
Spray | Sodium Chloride (0.65%) | 15% (v/v) |
| Anefrin Nasal
Spray | Oxymetazoline, 0.05% | 15% (v/v) |
| Nasal Drops | Phenylephrine, 0.5% | 15% (v/v) |
| Tamiflu®/Anti-
viral drugs | Zanamivir | 7.5 mg/mL |
| Antibacterial,
systemic | Tobramycin | 4 µg/mL |

Table 5-11. Potentially Interfering Substances in Xpert Flu/RSV XC Assay

24

| Substance/Class | Description/Active
Ingredient | Concentration
Tested |
|-------------------------|--------------------------------------------------------------------------------|-------------------------|
| Zicam®/Nasal
Gel | Luffa opperculata,
Galphimia glauca,
Histaminum
hydrochloricum Sulfur | 15% (w/v) |
| FluMist® | Live intranasal influenza
virus vaccine | 6.7% (v/v) |
| Nasal
corticosteroid | Fluticasone Propionate | 5 μg/mL |

Carry-Over Contamination

A study was conducted to demonstrate that single-use, self-contained GeneXpert cartridges prevent carry-over contamination in negative samples run followed by very high positive samples in the same GeneXpert module. The study consisted of a negative sample processed in the same GeneXpert module immediately followed by a very high influenza A sample (approximately 106 TCID50/test) or a very high RSV A sample (approximately 106 TCID50/test). This testing scheme was repeated 20 times on two GeneXpert modules for a total of 82 runs resulting in 40 positive and 42 negative specimens for each virus type. All 40 positive samples were correctly reported as Flu A POSITIVE; Flu B NEGATIVE; RSV NEGATIVE or Flu A NEGATIVE; Flu B NEGATIVE; RSV POSITIVE. All 42 negative samples were correctly reported as Flu A NEGATIVE; Flu B NEGATIVE; RSV NEGATIVE.

Fresh vs. Frozen Sample Equivalencv Study

Fresh and frozen specimen equivalency in the Xpert Flu/RSV XC Assay was evaluated by testing individual influenza and RSV strains at three different concentrations representing low positives (2X LoD), moderate positives (5X LoD), and high positives (10X LoD) in simulated background matrix. Negative samples consisted of simulated background matrix only. Fresh and frozen specimen equivalency was determined using one seasonal Flu A H3N2 strain (A/Victoria/361/2011), one Flu B strain (B/Wisconsin/01/11), one RSV A strain (RSV A/Long/MD/56), and one RSV B strain (RSV B/9320/MA/77). Replicates of 20 were tested for each specimen type and concentration. All positive and negative specimens were tested fresh, after one freezethaw cycle, and after two freeze-thaw cycles.

There was no statistically significant effect in the performance of the Xpert Flu/RSV XC Assay between fresh virus dilutions and two sequential freeze thaw cycles for positive and negative samples. All positive and negative replicates were correctly identified using the Xpert Flu/RSV XC Assay.

Linearitv

Not applicable, the Xpert Flu/RSV XC Assay is a qualitative assay.

25

Clinical Studies

Clinical Comparison Study

Performance characteristics of the Xpert Flu/RSV XC Assay were evaluated at six institutions in the U.S during the 2013-2014 influenza season. Due to the low prevalence of influenza viruses and the difficulty in obtaining fresh influenza and RSV-positive specimens, the specimen population for this study was supplemented with frozen prospective, and frozen pre-selected archived specimens.

Subjects included individuals with signs and symptoms of respiratory infection and whose routine care called for collection of nasal aspirate/wash (NA/W) specimens or nasopharyngeal (NP) swab specimens for influenza and/or RSV testing. For eligible subjects, aliquots of leftover specimens were obtained for testing with the Xpert Flu/RSV XC Assay and reference testing, and patient management continued at the site per their standard practice.

The Xpert Flu/RSV XC Assay performance was compared to a FDA-cleared comparator assay. Bi-directional sequencing was performed on specimens where the Xpert Flu/RSV XC Assay and the comparator assay were discrepant, and is provided for informational purposes only.

Overall Results

NA/W Specimens

A total of 657 NA/W specimens were tested for influenza A, influenza B and RSV by the Xpert Flu/RSV XC Assay and the comparator assay. Of the 657 NA/W specimens, 581 were fresh, prospectively collected and 76 were frozen, archived specimens.

On fresh, prospectively collected NA/W specimens, the Xpert Flu/RSV XC Assay demonstrated a PPA and NPA for detection of influenza A of 100% and 100%, respectively, relative to the comparator assay (Table 5-12). The Xpert Flu/RSV XC Assay PPA and NPA for influenza B were 99.2% and 100%, respectively (Table 5-12). The Xpert Flu/RSV XC Assay PPA and NPA for RSV were 98.5% and 99.6%, respectively (Table 5-12).

On frozen, archived NA/W specimens, the Xpert Flu/RSV XC Assay demonstrated a PPA and NPA for detection of influenza A of 97.1% and 100%, respectively, relative to the comparator assay (Table 5-12). The Xpert Flu/RSV XC Assay PPA and NPA for influenza B were 100% and 100%, respectively (Table 5-12). The Xpert Flu/RSV XC Assay PPA and NPA for RSV were 84.6% and 100%, respectively (Table 5-12).

26

| Specimen
Type | Target | n | TP | FP | TN | FN | PPA %
(95 CI) | NPA %
(95 CI) |
|------------------|--------|-----|-----|----|-----|----|---------------------|---------------------|
| Fresh | Flu A | 581 | 35 | 0 | 546 | 0 | 100
(90.0-100) | 100
(99.3-100) |
| | Flu B | 581 | 126 | 0 | 454 | 1a | 99.2
(95.7-100) | 100
(99.2-100) |
| | RSV | 581 | 128 | 2b | 449 | 2c | 98.5
(94.6-99.8) | 99.6
(98.4-99.9) |
| Frozen | Flu A | 76 | 34 | 0 | 41 | 1d | 97.1
(85.1-99.9) | 100
(91.4-100) |
| | Flu B | 76 | 1 | 0 | 75 | 0 | 100
(2.5-100) | 100
(95.2-100) |
| | RSV | 76 | 11 | 0 | 63 | 2e | 84.6
(54.6-98.1) | 100
(94.3-100) |

Table 5-12: Xpert Flu/RSV XC Assay Performance on NA/W Specimens

a Testing results by sequencing: NA; sample not sequenced.

Testing results by sequencing: 2 of 2 were RSV positive.

CTesting results by sequencing: 1 of 2 was RSV positive; 1 of 2 was RSV negative.

a Testing results by sequencing: 1 of 1 was Flu A negative.

Testing results by sequencing: 1 of 2 was RSV positive; 1 of 2 was RSV negative.

NP Swab Specimens

A total of 593 NP swab specimens were tested for influenza A, influenza B and RSV by the Xpert Flu/RSV XC Assay and the comparator assay. Of the 593 NP swab specimens, 190 were fresh, prospectively collected and 403 were frozen, archived specimens.

On fresh, prospectively collected NP swab specimens, the Xpert Flu/RSV XC Assay demonstrated a PPA and NPA for detection of influenza A of 85.7% and 98.9%, respectively, relative to the comparator assay (Table 5-13). The Xpert Flu/RSV XC Assay PPA and NPA for influenza B were 100% and 100%, respectively (Table 5-13). The Xpert Flu/RSV XC Assay PPA and NPA for RSV were 100% and 100%, respectively (Table 5-13).

On frozen, archived NP swab specimens, the Xpert Flu/RSV XC Assay demonstrated a PPA and NPA for detection of influenza A of 99.0% and 92.8%, respectively, relative to the comparator assay (Table 5-13). The Xpert Flu/RSV XC Assay PPA and NPA for influenza B were 98.8% and 100%, respectively (Table 5-13). The Xpert Flu/RSV XC Assay PPA and NPA for RSV were 90.4% and 99.1%, respectively (Table 5-13).

27

| Specimen
Type | Target | n | TP | FP | TN | FN | PPA %
(95 CI) | NPA %
(95 CI) |
|------------------|--------|-----|----|-----|-----|----|---------------------|---------------------|
| Fresh | Flu A | 190 | 6 | 2a | 181 | 1b | 85.7
(42.1-99.6) | 98.9
(96.1-99.9) |
| | Flu B | 190 | 3 | 0 | 187 | 0 | 100
(29.2-100) | 100
(98.0-100) |
| | RSV | 190 | 10 | 0 | 180 | 0 | 100
(69.2-100) | 100
(98.0-100) |
| Frozen | Flu A | 403 | 96 | 22c | 284 | 1d | 99.0
(94.4-100) | 92.8
(89.3-95.4) |
| | Flu B | 403 | 85 | 0 | 317 | 1e | 98.8
(93.7-100) | 100
(98.8-100) |
| | RSV | 403 | 47 | 3f | 348 | 5g | 90.4
(79.0-96.8) | 99.1
(97.5-99.8) |

Table 5-13: Xpert Flu/RSV XC Assay Performance on NP Swab Specimens

a Testing results by sequencing: 2 of 2 were Flu A positive.

bTesting results by sequencing: 1 of 1 was Flu A negative.

CTesting results by sequencing: 17 of 22 were Flu A positive; 5 of 22 were Flu A negative.

dTesting results by sequencing: 1 of 1 was Flu A negative.

Testing results by sequencing: 1 of 1 was Flu B negative.

"Testing results by sequencing: 2 of 3 were RSV positive; 1 of 3 was RSV negative.

8Testing results by sequencing: 1 of 5 was RSV positive; 4 of 5 were RSV negative.

Of the Xpert Flu/RSV XC Assay runs performed with eligible specimens, 98.6% (1236/1254) of these specimens were successful on the first attempt. The initial indeterminate rate was 1.4% (95% CI 0.9-2.3%). The remaining 18 gave indeterminate results on the first attempt (11 ERROR, 3 INVALID and 4 NO RESULT). Seventeen of the 18 specimens were retested, of which 14 yielded valid results after a single retest. There were four NA/W specimens with indeterminate results upon retest which were excluded in the analyses.

Reproducibility Study

A panel of 10 specimens with varying concentrations of influenza A, influenza B, and RSV was tested on ten different days by two different operators, at each of three sites (10 specimens x 1 time/day x 10 days x 2 operators x 3 sites). One lot of Xpert Flu/RSV XC Assay cartridges was used at each of the 3 testing sites. The Xpert Flu/RSV XC Assay was performed according to the Xpert Flu/RSV XC Assay procedure. Results are summarized in Table 5-14.

28

| Sample
ID | Site 1/GX Dx | | | Site 2/Infinity-80 | | | Site 3/Infinity-48 | | | % Total
Agreement by
Samplea |
|--------------------|-----------------|-----------------|------------------|--------------------|-----------------|------------------|--------------------|-----------------|------------------|------------------------------------|
| | Op 1 | Op 2 | Site | Op 1 | Op 2 | Site | Op 1 | Op 2 | Site | |
| Negative | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(60/60) |
| Flu A-
High Neg | 70.0%
(7/10) | 60.0%
(6/10) | 65.0%
(13/20) | 80.0%
(8/10) | 80.0%
(8/10) | 80.0%
(16/20) | 60.0%
(6/10) | 70.0%
(7/10) | 65.0%
(13/20) | 70.0%
(42/60) |
| Flu A-
Low Pos | 100%
(10/10) | 90.0%
(9/10) | 95.0%
(19/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 90.0%
(9/10) | 95.0%
(19/20) | 96.7%
(58/60) |
| Flu A-
Mod Pos | 100%
(10/10) | 90.0%
(9/10) | 95.0%
(19/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 98.3%
(59/60) |
| Flu B-
High Neg | 90.0%
(9/10) | 70.0%
(7/10) | 80.0%
(16/20) | 100%
(10/10) | 70.0%
(7/10) | 85.0%
(17/20) | 50.0%
(5/10) | 80.0%
(8/10) | 65.0%
(13/20) | 76.7%
(46/60) |
| Flu B-
Low Pos | 100%
(10/10) | 90.0%
(9/10) | 95.0%
(19/20) | 90.0%
(9/10) | 70.0%
(7/10) | 80.0%
(16/20) | 100%
(10/10) | 90.0%
(9/10) | 95.0%
(19/20) | 90.0%
(54/60) |
| Flu B-
Mod Pos | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(60/60) |
| RSV-
High Neg | 60.0%
(6/10) | 50.0%
(5/10) | 55.0%
(11/20) | 90.0%
(9/10) | 60.0%
(6/10) | 75.0%
(15/20) | 70.0%
(7/10) | 70.0%
(7/10) | 70.0%
(14/20) | 66.7%
(40/60) |
| RSV-
Low Pos | 77.8%b
(7/9) | 100%
(10/10) | 89.5%
(17/19) | 80.0%
(8/10) | 80.0%
(8/10) | 80.0%
(16/20) | 90.0%
(9/10) | 90.0%
(9/10) | 90.0%
(18/20) | 86.4%
(51/59) |
| RSV-
Mod Pos | 100%c
(9/9) | 100%
(10/10) | 100%
(19/19) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(10/10) | 100%
(10/10) | 100%
(20/20) | 100%
(59/59) |

Table 5-14: Summary of Reproducibility Results

A greement calculated based on expected result: Negative (targeted positivity: 0%) and High Neg (targeted positivity: 20-80%) samples; Positive for Low Pos (targeted positivity: 95%) and Mod Pos (targeted positivity: 100%) samples. one sample indeterminate on initial testing; retest not done.

°One sample 2x indeterminate.

The reproducibility of the Xpert Flu/RSV XC Assay was also evaluated in terms of the fluorescence signal expressed in Ct values for each target detected. The mean, standard deviation (SD), and coefficient of variation (CV) between-sites, between-days, and between-operators for each panel member are presented in Table 5-15. One replicate was performed per day per operator, therefore, operator and assay (within-run) precision are confounded.

29

Within-
Assay | | Total | |
|-----------------|-------------------------------|-------|------------|------------------|-----------|-----------------|-----------|--------------------------------------------|-----------|-------|-----------|
| | | | | SD | CV
(%) | SD | CV
(%) | SD | CV
(%) | SD | CV
(%) |
| Negative | SPC | 60 | 30.8 | 0.06 | 0.2 | 0 | 0 | 0.29 | 0.9 | 0.29 | 0.9 |
| Flu A- High Neg | FluA1 | 18 | 38.0 | 0 | 0 | 1.55 | 4.1 | 0.85 | 2.2 | 1.77 | 4.6 |
| | FluA2 | 0 | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| | Flu A-Low Pos | FluA1 | 58 | 34.9 | 0.38 | 1.1 | 0.10 | 0.3 | 1.28 | 3.7 | 1.34 |
| FluA2 | | 0 | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Flu A- Mod Pos | FluA1 | 59 | 33.5 | 0.49 | 1.5 | 0 | 0 | 1.29 | 3.9 | 1.38 | 4.1 |
| | FluA2 | 10 | 36.3 | NA | NA | NA | NA | NA | NA | NA | NA |
| Flu B- High Neg | FluB | 14 | 36.6 | 0.80 | 1.4 | 0 | 0 | 2.83 | 7.7 | 2.94 | 8.0 |
| Flu B-Low Pos | FluB | 54 | 33.4 | 0 | 0 | 1.07 | 3.2 | 1.76 | 5.3 | 2.06 | 6.2 |
| Flu B- Mod Pos | FluB | 60 | 32.1 | 0 | 0 | 0.38 | 1.2 | 1.47 | 4.6 | 1.51 | 4.7 |
| RSV-High Neg | RSV | 20 | 37.4 | 0 | 0 | 0.14 | 0.4 | 1.68 | 4.5 | 1.68 | 4.5 |
| RSV-Low Pos | RSV | 51 | 36.2 | 0.22 | 0.6 | 0 | 0 | 1.75 | 4.8 | 1.76 | 4.9 |
| RSV- Mod Pos | RSV | 60 | 35.1 | 0 | 0 | 0.24 | 0.9 | 1.20 | 3.4 | 1.24 | 3.5 |

Table 5-15: Summary of Reproducibility Data

4Results with non-zero Ct values out of 60.

Instrument System Precision

An in-house precision study was conducted to compare the performance of the GeneXpert Dx and the GeneXpert Infinity instrument systems. A panel of 10 specimens with varying concentrations of influenza A, influenza B, and RSV was tested on 12 different days by two operators. Each operator conducted four runs of each panel specimen per day on each of the two instrument systems (10 specimens x 2 times/ day x 12 days x 2 operators x 2 instrument systems). Three lots of Xpert Flu/RSV XC Assay cartridges were used for the study. The Xpert Flu/RSV XC Assay was performed according to the Xpert Flu/RSV XC Assay procedure. Results are summarized in Table 5-16.

30

| Sample | GeneXpert Dx | | | Infinity | | | % Total
Agreement
by Samplea |
|--------------------|------------------|------------------|------------------|------------------|------------------|------------------|------------------------------------|
| | Op 1 | Op 2 | Inst | Op 1 | Op 2 | Inst | |
| Negative | 100%
(48/48) | 100%
(48/48) | 100%
(96/96) | 100%
(48/48) | 100%
(48/48) | 100%
(96/96) | 100%
(192/192) |
| Flu A-
High Neg | 75.0%
(36/48) | 77.1%
(37/48) | 76.0%
(73/96) | 87.5%
(42/48) | 75.0%
(36/48) | 81.3%
(78/96) | 78.7%
(151/192) |
| Flu A-
Low Pos | 68.8%
(33/48) | 97.9%
(47/48) | 83.3%
(80/96) | 91.7%
(44/48) | 93.8%
(45/48) | 92.7%
(89/96) | 88.0%
(169/192) |
| Flu A-
Mod Pos | 97.9%
(47/48) | 100%
(48/48) | 99.0%
(95/96) | 93.8%
(45/48) | 97.9%
(47/48) | 95.8%
(92/96) | 97.4%
(187/192) |
| Flu B-
High Neg | 81.3%
(39/48) | 79.2%
(38/48) | 80.2%
(77/96) | 89.6%
(43/48) | 79.2%
(38/48) | 84.4%
(81/96) | 82.3%
(158/192) |
| Flu B-
Low Pos | 89.6%
(43/48) | 95.8%
(46/48) | 92.7%
(89/96) | 89.6%
(43/48) | 87.5%
(42/48) | 88.5%
(85/96) | 90.6%
(174/192) |
| Flu B-
Mod Pos | 97.9%
(47/48) | 100%
(48/48) | 99.0%
(95/96) | 100%
(48/48) | 100%
(48/48) | 100%
(96/96) | 99.5%
(191/192) |
| RSV-
High Neg | 89.6%
(43/48) | 77.1%
(37/48) | 83.3%
(80/96) | 87.5%
(42/48) | 83.3%
(40/48) | 85.4%
(82/96) | 84.4%
(162/192) |
| RSV-
Low Pos | 93.8%
(45/48) | 93.8%
(45/48) | 93.8%
(90/96) | 87.5%
(42/48) | 89.6%
(43/48) | 88.5%
(85/96) | 91.1%
(175/192) |
| RSV-
Mod Pos | 100%
(48/48) | 100%
(48/48) | 100%
(96/96) | 97.9%
(47/48) | 100%
(48/48) | 99.0%
(95/96) | 99.5%
(191/192) |

Table 5-16: Summary of Instrument System Precision Results (Dx vs. Infinity)

4 Agreement calculated based on expected result: Negative for Negative (targeted positivity: 0%) and High Neg (targeted positivity: 20-80%) samples; Positive for Low Pos (targeted positivity: 95%) and Mod Pos (targeted positivity: 100%) samples.

The precision of the Xpert Flu/RSV XC Assay was also evaluated in terms of the fluorescence signal expressed in Ct values for each target detected. The mean, standard deviation (SD), and coefficient of variation (CV) between-instruments, between-lots, between-days, between-operators, and within-assays for each panel member are presented in Table 5-17.

31

| Sample | Assav
Channel
(Analyte) | Na | Mean
Ct | Between-
Instrument | | Between-
Lot | | Between-
Day | | Between-
Operator | | Within-
Assay | | Total | |
|--------------------|-------------------------------|------|------------|------------------------|-----------|-----------------|-----------|-----------------|-----------|----------------------|-----------|------------------|-----------|-------|-----------|
| | | | | SD | CV
(%) | SD | CV
(%) | SD | CV
(%) | SD | CV
(%) | SD | CV
(%) | SD | CV
(%) |
| Negative | SPC | 192 | 30.6 | 0 | 0 | 0.19 | 0.6 | 0.06 | 0.2 | 0.02 | 0.1 | 0.36 | 1.2 | 0.41 | 1.3 |
| Flu A-
High Neg | FluA1 | 41 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| | FluA2 | 0 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Flu A-
Low Pos | FluA 1 | 169 | 35.6 | 0 | 0 | 0.42 | 1.2 | 0.93 | 2.6 | 0.28 | 0.8 | 1.61 | 4.5 | 1.93 | 5.4 |
| | FluA2 | 1 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Flu A-
Mod Pos | FluA l | 187 | 34.1 | 0 | 0 | 0.41 | 1.2 | 0.95 | 2.8 | 0 | 0 | 1.54 | 4.5 | 1.86 | ર : ર |
| | FluA2 | 14 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Flu B-
High Neg | FluB | 34 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Flu B-
Low Pos | FluB | 174 | 33.2 | 0 | 0 | 0.47 | 1.4 | 0 | 0 | 0.66 | 2.0 | 2.03 | 6.1 | 2.18 | 6.6 |
| Flu B-
Mod Pos | FluB | 191 | 32.1 | 0 | 0 | 0.17 | 0:5 | 0.25 | 0.8 | 0 | 0 | 1.73 | 5.4 | 1.75 | ર : ર |
| RSV-
High Neg | RSV | 30 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| RSV-
Low Pos | RSV | ા તર | 36.0 | 0 | 0 | 0.75 | 2.1 | 0 | 0 | 0.36 | 1.0 | 1.47 | 4.1 | 1.69 | 4.7 |
| RSV-
Mod Pos | RSV | 191 | 34.7 | 0 | 0 | 0.57 | 1.7 | 0.16 | 0:5 | 0 | 0 | 1.23 | 3.6 | 1.37 | 3.9 |

Table 5-17. Summary of Precision Data

4Results with non-zero Ct values out of 192.

Conclusions

The results of the nonclinical analytical and clinical performance studies summarized above demonstrate that the Xpert Flu/RSV XC Assay is substantially equivalent to the predicate devices.