XPERT MRSA/SA SSTI ASSAY

• K Number: K080837
• Device Name: XPERT MRSA/SA SSTI ASSAY
• Manufacturer: CEPHEID
• Date Cleared: 2008-09-24 ( 183 days)
• Product Code: NQX NOX
• Regulation Number: 866.1640

Intended Use

The Cepheid Xpert MRSA/SA Skin and Soft Tissues Infection Assay (Xpert MRSA/SA SSTI Assay) performed in the GeneXpert® Dx System is a qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) from skin and soft tissue infection swabs. The test utilizes automated real-time polymerase chain reaction (PCR) to detect MRSA/SA DNA. The Xpert MRSA/SA SSTI Assay is indicated for use in conjunction with other laboratory tests such as microbiology culture, and clinical data available to the clinician as an aid in the detection of MRSA/SA from skin and soft tissue infections. The Xpert MRSA/SA SSTI Assay is not intended to monitor treatment for MRSA/SA infections. Concomitant cultures for SA and MRSA are necessary to recover organisms for susceptibility testing or epidemiological typing. In a mixed culture containing MRSA/SA and other organisms (e.g. Gram negative bacilli, yeast), results can be false negative or variable depending on the concentration of MRSA/SA present, particularly if the concentration of MRSA/SA is close to the LoD of the assay.

Device Description

The Cepheid Xpert MRSA/SA Skin and Soft Tissue Infection Assay (Xpert MRSA/SA SSTI Assay) is a rapid, automated DNA test for simultaneously detecting MRSA and SA directly from skin and soft tissue specimen is collected on a double swab, which is placed in a tube containing elution reagent. Following brief vortexing, the eluted matcrial and two single-use reagents (Reagent 1 and Reagent 2) that are provided with the assay are transferred to different, uniquely-labeled chambers of the disposable fluidic cartridge (the Xpert MRSA/SA cartridge). The user initiates a test from the system user interface and places the cartridge into the GeneXpert® Dx System instrument platform, which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of DNA. In this platform, additional sample preparation, amplification, and real-time detection are all fully-automated and completely integrated. The GeneXpert® System consists of a GeneXpert instrument, personal computer, and the multi-chambered fluidic cartridges that are designed to complete sample preparation and real-time PCR for detection of MRSA and SA in approximately 50 minutes. Each system has 1 to 16 randomly accessible modules that are each capable of performing separate sample preparation and real-time PCR tests. Each module contains a syringe drive for dispensing fluids, an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and detection. The Xpert MRSA/SA Assay includes reagents for the simultaneous detection of the target organisms, SA and MRSA. The primers and probes in the Xpert MRSA/SA Assay detect nucleic acid sequences of the staphylococcal protein A (spa), the gene for MecA-Mediated Oxacillin resistance (mecA), and staphylococcal cassette chromosome (SCCmec) inserted in the SA chromosomal attB site. The test includes a sample processing control (SPC) to control for adequate processing of the target bacteria and to monitor the presence of inhibitor(s) in the PCR assay. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity, and dye stability.

Predicate Devices

K070462, K071026

Reference Devices

K851949, K863821, K042812, K020322, K023301

AI/ML (Artificial Intelligence / Machine Learning)

No
The device description focuses on automated real-time PCR and DNA detection, with no mention of AI or ML algorithms for analysis or interpretation.

Therapeutic

No
The device is an in vitro diagnostic test designed to detect MRSA/SA DNA to aid in the detection of MRSA/SA from skin and soft tissue infections. It does not provide any treatment or therapeutic function.

Diagnostic

Yes

The device is described as a "qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA)" and is indicated for use "as an aid in the detection of MRSA/SA from skin and soft tissue infections," which directly aligns with the definition of a diagnostic device.

SaMD (Software as a Medical Device)

No

The device description clearly outlines a system that includes significant hardware components, such as the GeneXpert® Dx System instrument platform, disposable fluidic cartridges, modules with syringe drives, ultrasonic horns, and thermocyclers. While software is involved in controlling the system and analyzing data, it is not a standalone software-only device.

IVD (In Vitro Diagnostic)

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

The "Intended Use / Indications for Use" section explicitly states: "The Cepheid Xpert MRSA/SA Skin and Soft Tissues Infection Assay (Xpert MRSA/SA SSTI Assay) performed in the GeneXpert® Dx System is a qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) from skin and soft tissue infection swabs."

This statement directly identifies the device as an in vitro diagnostic test.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The Cepheid Xpert MRSA/SA Skin and Soft Tissues Infection Assay (Xpert MRSA/SA SSTI Assay) performed in the GeneXpert® Dx System is a qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) from skin and soft tissue infection swabs. The test utilizes automated real-time polymerase chain reaction (PCR) to detect MRSA/SA DNA. The Xpert MRSA/SA SSTI Assay is indicated for use in conjunction with other laboratory tests such as microbiology culture, and clinical data available to the clinician as an aid in the detection of MRSA/SA from skin and soft tissue infections. The Xpert MRSA/SA SSTI Assay is not intended to monitor treatment for MRSA/SA infections. Concomitant cultures for SA and MRSA are necessary to recover organisms for susceptibility testing or epidemiological typing.

In a mixed culture containing MRSA/SA and other organisms (e.g. Gram negative bacilli, ycast), results can be false negative or variable depending on the concentration of MRSA/SA present, particularly if the concentration of MRSA/SA is close to the LoD of the assay.

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

NQX

Device Description

The Cepheid Xpert MRSA/SA Skin and Soft Tissue Infection Assay (Xpert MRSA/SA SSTI Assay) is a rapid, automated DNA test for simultaneously detecting MRSA and SA directly from skin and soft tissue specimen is collected on a double swab, which is placed in a tube containing elution reagent. Following brief vortexing, the eluted matcrial and two single-use reagents (Reagent 1 and Reagent 2) that are provided with the assay are transferred to different, uniquely-labeled chambers of the disposable fluidic cartridge (the Xpert MRSA/SA cartridge). The user initiates a test from the system user interface and places the cartridge into the GeneXpert® Dx System instrument platform, which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of DNA. In this platform, additional sample preparation, amplification, and real-time detection are all fully-automated and completely integrated.

The GeneXpert® System consists of a GeneXpert instrument, personal computer, and the multi-chambered fluidic cartridges that are designed to complete sample preparation and real-time PCR for detection of MRSA and SA in approximately 50 minutes. Each system has 1 to 16 randomly accessible modules that are each capable of performing separate sample preparation and real-time PCR tests. Each module contains a syringe drive for dispensing fluids, an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and detection.

The Xpert MRSA/SA Assay includes reagents for the simultaneous detection of the target organisms, SA and MRSA. The primers and probes in the Xpert MRSA/SA Assay detect nucleic acid sequences of the staphylococcal protein A (spa), the gene for MecA-Mediated Oxacillin resistance (mecA), and staphylococcal cassette chromosome (SCCmec) inserted in the SA chromosomal attB site.

The test includes a sample processing control (SPC) to control for adequate processing of the target bacteria and to monitor the presence of inhibitor(s) in the PCR assay. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity, and dye stability.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

skin and soft tissue

Indicated Patient Age Range

Not Found

Intended User / Care Setting

Operators with no clinical lab experience to experienced clinical laboratory technologists.

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

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

Non-Clinical Studies:

• Analytical Inclusivity Study on CDC Staphylococcus aureus Specimens:
  • Test: Xpert MRSA/SA Assay.
  • Samples: 21 MRSA strains (representing SCCmec types II, IV, IVa, IVb, IVc, and unknown types) and 3 MSSA strains from CDC, including USA100, USA300, and USA400 types.
  • Protocol: All strains tested in triplicate using 100 µL of stationary phase cell suspensions diluted 10 million-fold.
  • Results: All 21 MRSA strains were correctly reported MRSA positive; SA positive. All 3 MSSA strains were correctly reported MRSA negative; SA positive. Culture using BBL CHROMagar MRSA confirmed all Xpert test results.
• Analytical Inclusivity Study on Expanded Panel of Staphylococcus aureus Specimens:
  • Test: Xpert MRSA/SA Assay.
  • Samples: 121 additional Staphylococcus aureus strains (78 MRSA, 43 SA) selected for genetic diversity.
  • Protocol: Overnight cultures adjusted to 0.5 McFarland units, tested in triplicate using 100 µL of cultures further diluted 100 thousand to one million-fold. Discordant results characterized by catalase, tube coagulase, Gram stain, and cefoxitin disk diffusion.
  • Results: 116 of 121 strains correctly identified.
    • 3 of 78 MRSA strains reported MRSA negative; SA positive (further characterization indicated they were not resistant).
    • 2 of 43 SA strains reported MRSA positive; SA positive (further characterization indicated they were resistant).
    • All 12 known USA300 isolates were correctly reported MRSA positive and SA positive.
• Evaluation of Empty Cassette Variants:
  • Test: Xpert MRSA/SA Assay.
  • Samples: 22 "empty cassette variants" of Staphylococcus aureus isolates.
  • Protocol: Overnight cultures adjusted to 0.5 McFarland units, tested from cultures further diluted 100-fold (high) and 100 thousand-fold (low).
  • Results: All 22 isolates were correctly identified as MRSA negative and SA positive. Only Cts for spa and SCCmec targets were reported, no mecA Cts were reported.
• Limit of Detection Studies (Analytical Sensitivity):
  • Test: Xpert MRSA/SA Assay.
  • Samples: MRSA cells (6 isolates representing SCCmec types I, II, III, IVa, V, VI; USA100, USA400 types) and SA cells (3 isolates; USA900, USA1200 types)
  • Protocol: Diluted into a surrogate wound matrix of human origin (WBC concentrate, RBC, plasma). Replicates of 20 evaluated for each concentration. LoD defined as the lowest concentration with 95% confidence (19 of 20 replicates positive). Logistic regression used to determine estimate and 95% confidence intervals.
  • Key Results:
    • SA: For SA Strain ID N7129 (USA900), LoD (CFU/swab) = 51 (95% CI: 42-69). For 102-04 (USA1200), LoD = 87 (95% CI: 76-109). For 29213 (unknown), LoD = 123 (95% CI: 97-188).
    • MRSA: For 64/4176 (SCCmec I, USA500), LoD = 221 (95% CI: 195-271). For N315 (SCCmec II, USA100), LoD = 122 (95% CI: 106-152). For 11373 (SCCmec III, unknown), LoD = 124 (95% CI: 115-155). For MW2 (SCCmec IVa, USA400), LoD = 82 (95% CI: 68-113). For ST59-MRSA-V (SCCmec V, USA1000), LoD = 242 (95% CI: 208-305). For HDE288 (SCCmec VI, USA800), LoD = 183 (95% CI: 161-223).
    • Overall: 95% confidence of positive SA result with 123 CFU/wound swab, and positive MRSA result with 300 CFU/wound swab.
• Linearity:
  • Test: Xpert MRSA/SA Assay.
  • Protocol: Ten-fold serial dilutions (1e8 CFU/sample - 10 CFU/sample) of SA and MRSA isolates.
  • Results:
    • spa detection (SA): linear (r2 = 0.998) over 6 logs; mean Ct range 13.4 to 33.1; PCR efficiency 100%.
    • spa detection (MRSA): linear (r2 = 0.999) over 6 logs; mean Ct range 14.3 to 35.0; PCR efficiency 95.4%.
    • mecA detection (MRSA): linear (r2 = 0.999) over 6 logs; mean Ct range 14.2 to 35.3; PCR efficiency 93.3%.
    • SCCmec detection (MRSA): linear (r2 = 0.999) over 5 logs; mean Ct range 16.6 to 33.8; PCR efficiency 94.6%.
• Cross-reactivity Study (Analytical Specificity):
  • Test: Xpert MRSA/SA Assay.
  • Samples: 105 strains (98 ATCC, 7 NARSA) including phylogenetically related species and those found in hospital environments (methicillin-sensitive and resistant coagulase-negative staphylococci, Gram positive, Gram negative, yeast, aerobic, anaerobic).
  • Protocol: Two or more replicates of each isolate tested at 1.7 - 3.2 McFarland units.
  • Results: All isolates were reported MRSA negative and SA negative; none were detected. Analytical specificity was 100%.
• Evaluation of BORSA Strains:
  • Test: Xpert MRSA/SA Assay.
  • Samples: 7 well-characterized borderline oxacillin-resistant Staphylococcus aureus (BORSA) strains.
  • Protocol: Tested at high and low cell concentrations.
  • Results: All 7 BORSA isolates were correctly reported MRSA negative; SA positive. No mecA signals were reported. This demonstrates correct identification of BORSA strains without false positive MRSA results.
• Interfering Substances:
  • Test: Investigational study for Xpert MRSA/SA SSTI Assay and a non-clinical study.
  • Samples: Clinical specimens (848), including those with blood (428) and other non-specific substances (404). Non-clinical study evaluated potential interfering substances like blood, pus, plasma, topical ointments (antibiotic/antiseptic/pain relieving), debriding agents, and tinctures (Table 5.6a, 5.6b).
  • Results:
    • Clinical study: Fisher's exact tests showed no effect of blood or non-specific substances on assay performance.
    • Non-clinical study: Inhibition observed with StaphA + Septic (5% w/v), Hydrocortisone (5% w/v), and antibacterial hand sanitizer (5% w/v).

Clinical Studies:

• Clinical Performance:
  • Study Type: Multi-site prospective investigation study.
  • Sample Size: 848 specimens.
  • Data Source: Four US institutions, comparing Xpert MRSA/SA SSTI Assay with reference culture.
  • Protocol: Double swabs collected per subject. One for Xpert assay at enrolling center, one for site's standard method and central lab reference culture. Reference culture involved overnight enrichment, streaking on plates (with/without cefoxitin), presumptive colony confirmation (catalase, tube coagulase, Gram stain), and MecA-Mediated Oxacillin resistance testing (disk diffusion).
  • Overall Results:
    • Antibiotic use within 3 weeks prior to sample collection decreased culture positivity rates for SA (p=0.007) and MRSA (p=0.022), leading to higher false positive rates for Xpert assay in these cases.
    • 5 of 246 MRSA positive cultures had mixed infections; Xpert identified 3 as MRSA+, 2 as SA+/MRSA-.
    • Success rate on first attempt: 96.8% (427/441) for no antibiotic use, 97.0% (194/200) for unknown antibiotic use, 96.1% (199/207) for known antibiotic use.
  • Performance in Subjects with No Antibiotic Use (n=441):
    • Positive Percent Agreement (PPA) for MRSA+: 93.8% (95% CI: 88.6-97.1)
    • Negative Percent Agreement (NPA) for MRSA+: 97.3% (95% CI: 94.7-98.8)
    • PPA for SA+/MRSA+: 95.7% (95% CI: 92.2-97.9)
    • NPA for SA+/MRSA+: 89.5% (95% CI: 84.6-93.3)
  • Performance in Subjects with Unknown Antibiotic Use (n=200):
    • PPA for MRSA+: 94.0% (95% CI: 83.5-98.7)
    • NPA for MRSA+: 97.3% (95% CI: 93.3-99.3)
    • PPA for SA+/MRSA+: 96.9% (95% CI: 91.2-99.4)
    • NPA for SA+/MRSA+: 88.3% (95% CI: 80.5-93.8)
  • Performance in Subjects with Known Antibiotic Use (n=207):
    • PPA for MRSA+: 88.0% (95% CI: 75.7-95.5)
    • NPA for MRSA+: 92.4% (95% CI: 87.0-96.0)
    • PPA for SA+/MRSA+: 95.2% (95% CI: 88.3-98.7)
    • NPA for SA+/MRSA+: 76.4% (95% CI: 67.9-83.6)
• Empty Cassette Variants in Clinical Study (n=16 isolates):
  • Protocol: Isolates with positive spa and SCCmec, but no mecA detection (Ct = 0) by Xpert.
  • Results:
    • 15 of 16 were verified MRSA true negative relative to culture.
    • 14 of 16 were verified true positive SA relative to culture.
    • 1 isolate identified as MRSA by culture.
    • 2 isolates were both MRSA and SA negative by culture.
• Carry-Over Contamination Study:
  • Study Type: Laboratory study.
  • Sample Size: 42 runs (20 pairs of positive/negative samples + 1 extra).
  • Protocol: Negative sample processed immediately following a very high MRSA positive sample (roughly 10^7 CFU/test) in the same GeneXpert module, repeated 20 times across 2 modules.
  • Results: No evidence of carry-over contamination. All 21 positive samples reported MRSA positive: SA positive. All 21 negative samples reported MRSA negative; SA negative.
• Reproducibility Study (First):
  • Study Type: Multi-site reproducibility.
  • Sample Size: 10 specimens (varying concentrations of SA, MRSA, negative S. epidermidis) tested in duplicate on 10 different days at 3 sites (10 specimens x 2 times/day x 10 days x 3 sites = 600 tests).
  • Results: % Total Agreement = 94.2% (565/600).
    • For individual specimens, agreement ranged from 73.3% (MRSA1 Low Pos1) to 100% (Neg (MSSE), MRSA2 High Neg).
    • SPC Ct values %CV ranged from 2.36% to 2.66%.
    • Spa Ct values %CV ranged from 2.21% to 2.44%.
    • mecA Ct values %CV ranged from 2.16% to 2.40%.
    • SCCmec Ct values %CV ranged from 2.05% to 2.63%.
• Reproducibility Study (Second):
  • Study Type: Multi-site reproducibility.
  • Sample Size: 4 specimens (SA: 10X LoD, MRSA1: 10X LoD, MRSA2: 10X LoD, Negative Control: S. epidermidis) tested in duplicate on 10 different days at 3 sites (4 specimens x 2 times/day x 10 days x 3 sites = 240 tests).
  • Results: Correct results obtained in 239 of 240 tests (99.6% Total Agreement).
    • Site agreements: Site 1 (100%), Site 2 (100%), Site 3 (98.8%).
    • SPC Ct values %CV ranged from 3.09% to 7.34%.
    • Spa Ct values %CV ranged from 2.99% to 4.40%.
    • mecA Ct values %CV ranged from 4.22% to 4.29%.
    • SCCmec Ct values %CV ranged from 3.59% to 3.99%.

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

Positive Percent Agreement (PPA) / Sensitivity, Negative Percent Agreement (NPA) / Specificity.

Performance in Subjects with No Antibiotic Use (n=441):

• PPA (MRSA+): 93.8% (95% CI: 88.6-97.1)
• NPA (MRSA+): 97.3% (95% CI: 94.7-98.8)
• PPA (SA+/MRSA+): 95.7% (95% CI: 92.2-97.9)
• NPA (SA+/MRSA+): 89.5% (95% CI: 84.6-93.3)

Performance in Subjects with Unknown Antibiotic Use (n=200):

• PPA (MRSA+): 94.0% (95% CI: 83.5-98.7)
• NPA (MRSA+): 97.3% (95% CI: 93.3-99.3)
• PPA (SA+/MRSA+): 96.9% (95% CI: 91.2-99.4)
• NPA (SA+/MRSA+): 88.3% (95% CI: 80.5-93.8)

Performance in Subjects with Known Antibiotic Use (n=207):

• PPA (MRSA+): 88.0% (95% CI: 75.7-95.5)
• NPA (MRSA+): 92.4% (95% CI: 87.0-96.0)
• PPA (SA+/MRSA+): 95.2% (95% CI: 88.3-98.7)
• NPA (SA+/MRSA+): 76.4% (95% CI: 67.9-83.6)

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.

K070462, K071026

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.

K851949, K863821, K042812, K020322, K023301

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

§ 866.1640 Antimicrobial susceptibility test powder.

(a)
Identification. An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases.(b)
Classification. Class II (performance standards).

Summary

0

K080837

5.0 510(k) Summary

SEP 2 4 2008

As required by 21 CFR Section 807.92(c).

| Submitted by: | Cepheid
904 Caribbean Drive
Sunnyvale, CA 90489
Phone number: [phone]
Fax number: [phone] |
|---------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------|
| Contact: | Russel K. Enns, Ph.D. |
| Date of Preparation: | September 19, 2008 |
| Device: | |
| Trade name: | Xpert MRSA/SA SSTI Assay |
| Common name: | Staphylococcus aureus (SA) and methicillin-resistant
Staphylococcus aureus (MRSA) from skin and soft tissue
infections Assay. |
| Type of Test: | Nucleic Acid Amplification Test, DNA, Staphylococcus
aureus (SA) and Methicillin-resistant Staphylococcus
aureus (MRSA), qualitative |
| Classification name: | Antimicrobial susceptibility test powder |
| Regulation number: | 866.1640 |
| Procode: | NQX |
| Classification
Advisory Committee: | Microbiology |
| Panel: | 83 |
| Predicate Device: | Cepheid Xpert MRSA Assay [510(k) no. K070462] |

Device Description:

The Cepheid Xpert MRSA/SA Skin and Soft Tissue Infection Assay (Xpert MRSA/SA SSTI Assay) is a rapid, automated DNA test for simultaneously detecting MRSA and SA directly from skin and soft tissue specimen is collected on a double swab, which is placed in a tube containing elution reagent. Following brief vortexing, the eluted matcrial and two single-use reagents (Reagent 1 and Reagent 2) that are provided with the assay are transferred to different, uniquely-labeled chambers of the disposable fluidic cartridge (the Xpert MRSA/SA cartridge). The user initiates a test from the system user interface and places the cartridge into the GeneXpert® Dx System instrument platform, which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of DNA. In this platform, additional sample preparation, amplification, and real-time detection are all fully-automated and completely integrated.

1

The GeneXpert® System consists of a GeneXpert instrument, personal computer, and the multi-chambered fluidic cartridges that are designed to complete sample preparation and real-time PCR for detection of MRSA and SA in approximately 50 minutes. Each system has 1 to 16 randomly accessible modules that are each capable of performing separate sample preparation and real-time PCR tests. Each module contains a syringe drive for dispensing fluids, an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and detection.

The Xpert MRSA/SA Assay includes reagents for the simultaneous detection of the target organisms, SA and MRSA. The primers and probes in the Xpert MRSA/SA Assay detect nucleic acid sequences of the staphylococcal protein A (spa), the gene for MecA-Mediated Oxacillin resistance (mecA), and staphylococcal cassette chromosome (SCCmec) inserted in the SA chromosomal attB site.

The test includes a sample processing control (SPC) to control for adequate processing of the target bacteria and to monitor the presence of inhibitor(s) in the PCR assay. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity, and dye stability.

Device Intended Use:

The Cepheid Xpert MRSA/SA Skin and Soft Tissues Infection Assay (Xpert MRSA/SA SSTI Assay) performed in the GeneXpert® Dx System is a qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) from skin and soft tissue infection swabs. The test utilizes automated real-time polymerase chain reaction (PCR) to detect MRSA/SA DNA. The Xpert MRSA/SA SSTI Assay is indicated for use in conjunction with other laboratory tests such as microbiology culture, and clinical data available to the clinician as an aid in the detection of MRSA/SA from skin and soft tissue infections. The Xpert MRSA/SA SSTI Assay is not intended to monitor treatment for MRSA/SA infections. Concomitant cultures for SA and MRSA are necessary to recover organisms for susceptibility testing or epidemiological typing.

In a mixed culture containing MRSA/SA and other organisms (e.g. Gram negative bacilli, ycast), results can be false negative or variable depending on the concentration of MRSA/SA present, particularly if the concentration of MRSA/SA is close to the LoD of the assay.

Substantial Equivalence:

The Xpert MRSA/SA SSTI Assay is substantially equivalent to two molecular-based MRSA and SA assays, Cepheid Xpert™ MRSA Assay (K070462) and the BD GeneOhm StaphSR Assay (K071026). All three assays detect MRSA and the Xpert MRSA/SA and the BD GeneOhm StaphSR Assay detect both SA and MRSA; all three assays determine the presence of the target organisms through real-time PCR amplification and fluorogenic target-specific hybridization detection. Both Cepheid assays utilize the same fullyautomated instrument system, the Cepheid GeneXpert Dx System.

2

The Xpert MRSA/SA SSTI Assay simultaneously detects SA and MRSA from skin and soft tissue specimens. The Xpert MRSA Assay detects MRSA from nasal swab specimens. The BD GeneOhm StaphSR Assay detects SA and MRSA from positive blood cultures. Table 5.1 shows the similarities and differences between the Xpert MRSA/SA SSTI Assay and the two molecular-based predicate devices.

The Xpert MRSA/SA SSTI is also substantially equivalent to conventional microbiologybased predicate devices that identify (ID) and/or test for antimicrobial susceptibility (AST) of gram positive organisms, including Staphylococcus species of human origin from pure culture isolates. These conventional microbiology-based predicates accommodate multiple specimen types, including swabbed specimens of skin and soft tissue infections. These conventional microbiology-based predicates are:

• . Remel Staphaurex Latex Agglutination Test (K851949),
• BBL (BD) Oxacillin Screen Agar (K863821), .
• . BD BBL CHROMagar MRSA (K042812
• BD Phoenix Automated Microbiology ID/AST System (K020322 and K023301). .

Table 5.2 compares the new device with the conventional microbiology-based assays for SA. Table 5.3 compares the new device with the conventional microbiology-based assays for MRSA.

A multi-center study was conducted on 848 patients to determine the performance characteristics of the device relative to the sensitivity and specificity of culture and susceptibility testing, the current standard of care. The test results showed the Xpert MRSA/SA SSTI to be substantially equivalent to the current standard of care, identification of Staphyloccoccus aureus from solid media by catalase, coagulase, and Gram stain, and susceptibility by cefoxitin disk diffusion test.

3

Table 5.1

Similarities and Differences Between the Xpert MRSA/SA SSTI Assay and the Molecular-based Predicate Devices ______________________________________________________________________________________________________________________________________________________________________________

Similarities
	Device		Predicates
Item	Xpert MRSA/SA SSTI Assay	Xpert MRSA
Assay
(K070462)	BD GeneOhm™
StaphSR Assay
(K071026)
Intended Use	Rapid detection of MRSA and
SA	MRSA only	Same
Indication for Use	Identification of MRSA and SA	MRSA only	Same
Technological
Principles	Fully-automated nucleic acid
amplification (DNA); real-time
PCR	Same	Same
Test Cartridge	Disposable single-use, multi-
chambered fluidic cartridge.	Same	Disposable
single-use PCR
tube
Instrument System	Cepheid GeneXpert Dx System	Same	Cepheid
SmartCycler
Fluidics	Self-contained and automated
after swab elution and two
single-dose reagent additions.	Same	Manual
Probes	TaqMan® Probes	Same	Molecular
Beacons
Internal Controls	Sample processing control
(SPC) and probe check control
(PCC).	Same	One internal
reagent control
and external
positive and
negative controls
required per run
DNA Target
Sequence	Sequence incorporating the
insertion site (attBssc) of
Staphylococcal Cassette
Chromosome mec (SCCmec)
for detection of MRSA.	Same	Same
Sequence specific to
methicillin/oxacillin resistance
(mecA gene)	N/A	N/A
Rapid test results	Approximately 50 minutes to
results.	Approximately
75 minutes to
results.	Approximately
60-75 minutes.
Similarities
	Device	Predicates
Item	Xpert MRSA/SA SSTI Assay	Xpert MRSA
Assay
(K070462)	BD GeneOhm™
StaphSR Assay
(K071026)
Users	Operators with no clinical lab
experience to experienced
clinical laboratory
technologists.	Same.
Categorized as
a CLIA
moderate
complexity
assay.	CLIA High
Complexity
Laboratory Users
Differences
Item	Device	Predicates
	Xpert MRSA/SA SSTI Assay	Xpert MRSA
Assay
(K070462)	BD GeneOhm™
StaphSR Assay
(K071026)
Intended Use	Simultaneous rapid detection of
SA and MRSA.	Only detects
MRSA.	Same
Specimen Type	Direct from skin and soft tissue
infection swabs.	Direct from
nasal swabs.	Direct from
Positive Blood
Cultures
DNA Target
Sequence	Sequence specific to
Staphylococcus aureus species
( spa gene)	N/A	Sequence specific to
Staphylococcus aureus species
( nuc gene)
Ability to identify
correctly "Empty
Cassette Variants"	Yes, sequence specific to
Staphylococcus aureus species
( mecA gene)	No	No

4

Table 5.2

Similarities and Differences Between the Xpert MRSA/SA SSTI Assay and the Conventional Microbiology-based Predicate Devices for

Staphylococcus aureus (SA) only

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| | Xpert MRSA/SA SSTI
Assay | Staphaurex
Latex
Agglutination
Test for SA
K851949 | BD Phoenix
Automated
Microbiology
System for SA
K020322 |
|----------------|--------------------------------------------------------------|----------------------------------------------------------------|---------------------------------------------------------------------|
| Intended Use | Detection of SA | Same | Same |
| Single use | Yes | Same | Same |
| Assay Controls | Positive Control: SA
Negative Control: S.
epidermidis | Same | Same |

:

:

Differences
Item	Device	Predicates (SA only)
	Xpert MRSA/SA SSTI
Assay	Staphaurex
Latex
Agglutination
Test for SA
K851949	BD Phoenix
Automated
Microbiology
System for SA
K020322
Mode of
Detection	Sequence specific to
Staphylococcus aureus
species (spa gene)	Clumping factor
and protein A	Microbial
utilization and
degradation of
specific
substrates
Specimen Type	Direct from skin and soft
tissue infection swabs.	Staphylococcus
species	Gram Positive
organisms
Assay format	Amplification: PCR
Detection: Fluorogenic target-
specific hybridization	Agglutination
with latex
particles
sensitized with
fibrinogen and
IgG	Conventional,
chromogenic and
fluorogenic
biochemical tests
for identification
(ID) and
antimicrobial
resistance test
(AST)
Interpretation of
test results	Diagnostic software of the
GeneXpert Dx System	Visual
interpretation	Automated

6

Table 5.3

Similarities and Differences Between the Xpert MRSA/SA SSTI Assay and the Conventional Microbiology-based Predicate Devices for

Similarities
Item	Device	Predicates (MRSA only)
	Xpert
MRSA/SA SSTI
Assay	Mueller
Hinton Agar
w/ 4% NaCl
and Oxacillin
(Oxacillin
Screen Agar
Test)
K863821	BBL
CHROMagar
MRSA
(K042812)	BD Phoenix
Automated
Microbiology
System
K023301
Intended
Use	Detection of
MRSA	Same	Same	Same
Single use	Yes	Same	Same	Same
Assay
Controls	Positive Control:
MRSA
Negative Control:
SA	Same	Same	Same

Methicillin-Resistant Staphylococcus aureus (MRSA)

Differences
Item	Device	Predicates (MRSA only)
	Xpert
MRSA/SA SSTI
Assay	Mueller
Hinton Agar
w/ 4% NaCl
and Oxacillin
(Oxacillin
Screen Agar
Test)
K863821	BBL
CHROMagar
MRSA
(K042812)	BD Phoenix
Automated
Microbiology
System
K023301
Differences
Item	Device	Predicates (MRSA only)
	Xpert
MRSA/SA SSTI
Assay	Mueller
Hinton Agar
w/ 4% NaCl
and Oxacillin
(Oxacillin
Screen Agar
Test)
K863821	BBL
CHROMagar
MRSA
(K042812)	BD Phoenix
Automated
Microbiology
System
K023301
Mode of
Detection
for
methicillin
resistance	SCCmec gene
specific for
MRSA
mecA gene
specific for
methicillin/
oxacillin
resistance	Growth on
Mueller Hinton
Agar with 4%
NaCl and 6 ug/ml
oxacillin	Use of specific
Chromogenic
substrates and
cefoxitin to
differentiate
MRSA from
other organisms	Utilizes a
redox indicator
for detection of
organism
growth in the
presence of an
antimicrobial
agent
Specimen
Type	Direct from skin
and soft tissue
infection swabs.	Pure culture
isolate of
Staphylococcus
aureus	Direct from
Anterior nares	Pure culture
isolate of
Staphylococcus
aureus
Assay
format	Amplification:
PCR
Detection:
Fluorogenic
target-specific
hybridization	Phenotypic
detection based
on a 24 hour
growth of SA
inoculated on
media	Phenotypic
detection base
on a 24-48 hour
growth of SA
(mauve
colonies)
inoculated on
media	AST panels
containing
MIC tests for
several
antimicrobial
agents
Interpretatio
n of test
results	Diagnostic
software of the
GeneXpert Dx
System	Manual: Visual
interpretation	Manual: Visual
interpretation	Automated

7

Non-Clinical Studies:

Analytical Inclusivity Study on CDC Staphylococcus aureus Specimens

The analytical inclusivity of the Xpert MRSA/SA Assay was determined using Staphylococcus aureus strains that were reported by the Center for Disease Control

8

(CDC) to be representative of MRSA and MSSA strains currently encountered in the healthcare community. All strains were tested in triplicate using 100 µL of stationary phase cell suspensions diluted 10 million-fold. The panel consisted of MRSA strains representing SCCmec types II. IV. IVa. IVb. and IVc in addition to several unknown types. Data supplied by the Center for Disease Control (CDC) indicated these strains, when characterized by pulsed-field gel electrophoresis (PFGE), represent numerous USA types including USA100, the most common hospital-acquired strain and USA300 and USA400, the most common community-acquired strains.1

All 21 MRSA strains were correctly reported MRSA positive; SA positive using the Xpert MRSA/SA Assay. Additionally, each MSSA strain (n=3) was correctly reported MRSA negative: SA positive. Culture using BBL CHROMagar MRSA confirmed all Xpert test results. Colony forming units per assay were determined by plate counts in duplicate.

Analytical Inclusivity Study on Expanded Panel of Staphylococcus aureus Specimens

One hundred twenty-one (121) additional Staphylococcus aureus strains were tested using the Xpert MRSA/SA Assay. Overnight cultures were grown in Brain Heart Infusion (BHI) broth and adjusted to 0.5 McFarland units. All strains were tested in triplicate using 100 µL of cultures further diluted 100 thousand to one million-fold.

MRSA (78) and SA (43) strains were selected to broadly represent the range of genetic diversity found in the species Staphylococcus aureus based on phylogenetic structure. Selections represent primary lineages with emphasis on specific clonal complexes within which MRSA is predominantly observed. Lineages that contain MRSA and SA, as well as those that contain SA exclusively were included.

The Xpert MRSA/SA Assay correctly identified 116 of 121 strains. The 5 discordants were charactcrized by catalase, tube coagulase, and Gram stain. MecA-Mediated Oxacillin resistance was assessed by disk diffusion using a 30 ug cefoxitin disk and a diameter cut-off of 21/22 mm.

Three (3) of 78 MRSA strains were reported MRSA negative; SA positive using the Xpert assay. Further characterization indicates these strains are not resistant and were correctly reported MRSA negative; SA positive.

Two (2) of 43 SA strains were reported MRSA positive; SA positive using the Xpert assav. Further characterization indicates these strains arc resistant and were correctly reported MRSA negative; SA positive.

Each of the 12 known USA300 isolates were correctly reported MRSA positive and SA positive as expected.

1 McDougal L. Steward C. Killgore G. Chaitram J. McAllister S. Tenover F. Pulsed-Field Gel Electrophoresis Typing of Oxacillin-Resistant Staphylococcus aureus Isolates from the United States: Establishing a national Database. J Clin Micro 2003;41(11):5113-20.

9

Evaluation of Empty Cassette Variants

Twenty-two (22) Staphylococcus aureus isolates identified as "empty cassette variants" were tested using the Xpert MRSA/SA Assay. Overnight cultures were adjusted to 0.5 McFarland units. All strains were tested from cultures further diluted 100-fold (high) and 100 thousand-fold (low).

The Xpert MRSA/SA Assay correctly identified all 22 isolates as MRSA negative and SA positive. At both cell concentrations tested, only Cts for the spa and SCCmec targets were reported. No mecA Cts were reported

Analytical Sensitivity

Limit of Detection Studies

Studies were performed to determine the 95% confidence intervals for the analytical limit of detection (LoD) of Staphylococcus aureus (SA) cells and methicillin-resistant Staphylococcus aureus (MRSA) cells diluted into a surrogate wound matrix of human origin. The surrogate wound matrix consisted of a white blood cell (WBC) concentrate prepared from whole blood by centrifugation. The matrix also contained red blood cells (RBC) and plasma, and a negligible amount of anticoagulant (CPD or CPDA-1). The limit of detection is defined as the lowest number of colony forming units (CFU) 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.

For MRSA. replicates of 20 were evaluated at each MRSA concentration tested (CFU/swab) for 6 individual isolates representing SCCmec types I, II, III, IVa, V, and VI. When characterized by pulsed-field gel electrophoresis (PFGE), USA100, the most common healthcare-acquired strain and USA400, one of the most common communityacquired strains were represented.

For SA. replicates of 20 were evaluated at each SA concentration (CFU/swab) for 3 individual SA isolates. USA types USA900 and USA1200 werc represented.

The estimate and confidence intervals were determined using logistic regression with data (number of positive results per number of replicates at each level) over the range of CFU/swab tested. The confidence intervals were determined using maximum likelihood estimates on the logistic model parameters using the large sample variance-covariance matrix. The LoD point estimates and 95% upper and lower confidence intervals for each SA and each MRSA SCCmec type tested are summarized in Tables 5.4 and 5.5.

Image /page/9/Figure/9 description: This image is a table titled "Table 5.4: LoD and Confidence Intervals - SA". The table contains data for SA Strain ID N7129. The PFGE is USA900, the LoD (CFU/swab) is 51, the lower 95% CI is 42, and the upper 95% CI is 69.

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102-04	USA1200	87	76	109
29213	unknown	123	97	188

| MRSA Strain ID | SCCmec Type | PFGE | LoD
(CFU/swab) | Lower
95% CI | Upper
95% CI |
|----------------|-------------|---------|-------------------|-----------------|-----------------|
| 64/4176 | I | USA500 | 221 | 195 | 271 |
| N315 | II | USA100 | 122 | 106 | 152 |
| 11373 | III | unknown | 124 | 115 | 155 |
| MW2 | IVa | USA400 | 82 | 68 | 113 |
| ST59-MRSA-V | V | USA1000 | 242 | 208 | 305 |
| HDE288 | VI | USA800 | 183 | 161 | 223 |
| 64/4176 | I | USA500 | 221 | 195 | 271 |

Table 5.5: LoD and Confidence Intervals - MRSA

The results of this study indicate that the Xpert MRSA/SA SSTI Assay will produce a positive SA result 95% of the time with 95% confidence for a wound swab containing 123 CFU and a positive MRSA result 95% of the time with 95% confidence for a wound swab containing 300 CFU.

Linearity

A study was conducted to define the reportable range of the Xpert MRSA/SA Assay and demonstrate a linear relationship between SA and MRSA input and assay output (Ct). Linearity was evaluated using ten-fold serial dilutions (1e8 CFU/sample - 10 CFU/sample) of SA and MRSA isolates.

The Xpert MRSA/SA Assay responds linearly (r2 = 0.998) with respect to spa detection as a function of SA cell input over 6 logs. The mean reportable Ct range = 13.4 to 33.1. PCR efficiency for the spa reaction is 100%.

The Xpert MRSA/SA Assay responds linearly (r2 = 0.999) with respect to spa detection as a function of MRSA cell input over 6 logs. The mean reportable Ct range = 14.3 to 35.0. PCR efficiency for the spa reaction is 95.4%.

The Xpert MRSA/SA Assay responds linearly (r2 = 0.999) with respect to mecA detection as a function of MRSA cell input over 6 logs. The mean reportable Ct range = 14.2 to 35.3. PCR efficiency for the mecA reaction is 93.3%.

The Xpert MRSA/SA Assay responds linearly (r2 = 0.999) with respect to SCCmec detection as a function of MRSA cell input over 5 logs. The mean reportable Ct range for SCCmec is 16.6 to 33.8. PCR efficiency for the mec reaction is 94.6%

Analytical Specificity

11

Cross-reactivity Study

One hundred five (105) strains were collected, quantitated and tested using the Xpert MRSA/SA Assay. The 98 cultures from the American Type Culture Collection (ATCC) and 7 strains from the Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) represent species phylogenetically related to Staphylococcus aureus or those potentially encountered in a hospital environment.

Of these, methicillin-sensitive coagulase negative staphylococci (29) and methicillinresistant coagulase negative staphylococci (9) were included. The organisms tested were identified as either Gram positive (74), Gram negative (28), or yeast (3). The organisms were further classified as either aerobic (95) or anaerobic (10).

Two (2) or more replicates of each isolate were tested at 1.7 - 3.2 McFarland units. Under the conditions of the study, all isolates were reported MRSA negative and SA negative; none of the isolates were detected by the Xpert MRSA/SA Assay. Positive and Negative controls were included in the study. The analytical specificity was 100%.

Evaluation of BORSA Strains

Seven (7) well characterized borderline oxacillin-resistant Staphylococcus aureus (BORSA) strains were tested, including one apparent "empty cassette" (see above). Methicillin-resistant Staphylococcus aureus is resistant to all ß-lactam drugs through the alternative penicillin-binding protein PBP2a encoded by meca15. BORSA strains are mecA negative, but exhibit an oxacillin minimum inhibitory concentration (MIC) ≥ 2 and mecA
Level	Mean	Std Dev	%CV
MRSA1 Moderate Pos	29.78	1.28	4.29
MRSA2 Moderate Pos	29.32	1.24	4.22

SCCmec
Level	Mean	Std Dev	%CV
MRSA1 Moderate Pos	31.49	1.26	3.99
MRSA2 Moderate Pos	31.05	1.12	3.59

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Conclusions

The results of the nonclinical and clinical performance studies summarized above demonstrate that the MRSA/ST SSTI Assay is as effective, and performs as well as or better than the predicate device.

1000

.

22

DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/22/Picture/1 description: The image shows the seal of the Department of Health & Human Services (HHS). The seal features the department's name encircling a stylized caduceus symbol. The caduceus is a symbol of medicine and healthcare, often depicted as a staff with two snakes coiled around it.

Public Health Service

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

SEP 2 4 2008

Russel K. Enns, Ph.D. Senior Vice President Regulatory & Clinical Affairs, Quality System and Reimbursement Cepheid, Inc. 904 Caribbean Drive Sunnyvale, CA 94089

Re: K080837

Trade/Device Name: Xpert™ MRSA/SA SSTI Assay Regulation Number: 21 CFR 866.1640 Regulation Name: Antimicrobial Susccptibility Test Powder Regulatory Class: Class II Product Code: NOX Dated: August 1, 2008 Received: August 4, 2008

Dear Dr. Enns:

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, isting of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. 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); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).

23

Page 2 -

This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at 240-276-0450. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding postmarket surveillance, please contact CDRH's Office of Surveillance and Biometric's (OSB's) Division of Postmarket Surveillance at 240-276-3474. For questions regarding the reporting of device adverse events (Medical Device Reporting (MDR)), please contact the Division of Surveillance Systems at 240-276-3464. You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number [phone] or [phone] or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.

Sincerely yours,

Sally attaym

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

Enclosure

24

4.0 Indications for Use Statement

510(k) Number (if known): K080837

Device Name: Xpert MRSA/SA SSTI

Indications for Use:

The Cepheid Xpert MRSA/SA Skin and Soft Tissues Infection Assay (Xpert MRSA/SA SSTI Assay) performed in the GeneXpert® Dx System is a qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) from skin and soft tissue infection swabs. The test utilizes automated real-time polymerase chain reaction (PCR) to detect MRSA/SA DNA. The Xpert MRSA/SA SSTI Assay is indicated for use in conjunction with other laboratory tests such as microbiology culture, and clinical data available to the clinician as an aid in the detection of MRSA/SA from skin and soft tissue infections. The Xpert MRSA/SA SSTI Assay is not intended to monitor treatment for MRSA/SA infections. Concomitant cultures for SA and MRSA are necessary to recover organisms for susceptibility testing or epidemiological typing. In a mixed culture containing MRSA/SA and other organisms (e.g. Gram negative bacilli, yeast), results can be false negative or variable depending on the concentration of MRSA/SA present, particularly if the concentration of MRSA/SA is close to the LoD of the assay.

Prescription Use X (Part 21 CFR 801 Subpart D)

AND/OR Over-The-Counter Use (21 CFR 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

Freddie L. Poole

Vision Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K080837