The IQuum Liat™ Influenza A/B Assay performed on the Liat™ Analyzer is an automated multiplex real-time RT-PCR assay for the rapid in vitro qualitative detection and discrimination of influenza A virus and influenza B virus RNA in nasopharyngeal swab specimens from patients with signs and symptoms of respiratory infection in conjunction with clinical and epidemiological risk factors. The test is intended for use as an aid in the differential diagnosis of influenza A and influenza B in humans and is not intended to detect influenza C.

Negative results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other patient management decisions. Conversely, positive results do not rule-out bacterial infection or co-infection with other viruses. The agent detected may not be the definite cause of disease.

Performance characteristics for influenza A were established when influenza A/H1 and A/H3 were the predominant influenza A viruses in circulation. When other 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.

Device Description

The Liat™ Influenza A/B Assay is a rapid, automated in vitro diagnostic test for the detection and differentiation of Influenza type A and type B viral RNA in nasopharyngeal swab (NPS) specimens in universal transport media (UTM) from patients signs and symptoms of respiratory infection. The assay targets a well-conserved region of the matrix gene of Influenza A viral RNA (Inf A target) and non-structural protein (NS) gene of Influenza B (Inf B target). An Internal Process Control (IPC) is also included. The IPC is present to control for adequate processing of the target viruses and to monitor the presence of inhibitors in the RT-PCR reactions.

The Liat Influenza A/B Assay is performed on the lab-in-a-tube technology platform. The system consists of a disposable Liat Influenza A/B Assay Tube and the Liat™ Analyzer. The Liat™ Tube uses a flexible tube as a sample vessel. It contains all required unit dose reagents prepacked in tube segments, separated by peelable seals, in the order of reagent use. Manipulating a Liat Tube, the Liat Analyzer performs all assay steps from raw sample and report assay result automatically, During the testing process, multiple sample processing actuators of the analyzer compress the Liat Tube to selectively release reagents from tube segments, move the sample from one segment to another, and control reaction volume, temperature and time to conduct sample preparation, nucleic acid extraction, target enrichment, inhibitor removal, nucleic acid elution and real-time RT-PCR. An embedded microprocessor controls and coordinates the actions of these sample processors to perform all required assay processes within the closed Liat Tube. Turnaround time from sample input to result is ~20 minutes.

AI/ML Overview

1. Table of Acceptance Criteria and Reported Device Performance:

The document provided is a 510(k) Summary for the IQuum Liat™ Influenza A/B Assay and Liat™ Analyzer, a diagnostic device. For diagnostic devices like this, "acceptance criteria" are typically defined by performance metrics (e.g., sensitivity, specificity, accuracy) that demonstrate the new device is "substantially equivalent" to a legally marketed predicate device. While explicit numerical acceptance criteria are not always stated directly in the summary, the study's results (performance) serve to demonstrate this equivalence. The key performance indicators presented are clinical agreement (sensitivity and specificity) and analytical performance (limit of detection, reactivity, cross-reactivity, interference, precision, reproducibility).

Here's a table summarizing the reported device performance, which the FDA presumably found acceptable for clearance based on substantial equivalence.

Performance Metric	Acceptance Criteria (Implied by Predicate Equivalence)	Reported Device Performance (Liat™ Influenza A/B Assay)
Limit of Detection (LOD)	Must be comparable to relevant predicate or clinical needs.	Influenza A: Ranges from $10^{-1}$ to $10^{-2}$ TCID50/mL for tested strains (A/Brisbane/10/2007, A/Brisbane/59/2007, A/NY/01/2009). Influenza B: Ranges from $10^{-1}$ to $10^{-3}$ TCID50/mL for tested strains (B/Florida/04/06, B/Malaysia/2506/04).
Reactivity	Must detect a broad range of clinically relevant influenza strains.	Detected all 22 Influenza A strains (8 seasonal H1, 8 seasonal H3, 3 2009 H1N1, 3 swine origin) and all 10 Influenza B strains tested.
Cross-Reactivity	No cross-reactivity with common non-influenza respiratory pathogens/microorganisms at specified concentrations.	Showed no cross-reactivity for the panel of 31 human pathogens (bacteria at $10^4-10^6$ CFU/mL, viruses at $10^3-10^5$ TCID50/mL).
Interference	No interference from common microorganisms or substances at specified concentrations.	Microorganisms: No interference with detection of Inf A or Inf B by 31 human pathogens (bacteria at $10^4-10^6$ CFU/mL, viruses at $10^3-10^5$ TCID50/mL) when spiked with Inf A or Inf B at 3x LOD. Substances: No interference from 9 common substances (mucin, blood, nasal sprays, corticosteroids, gels, lozenges, antibiotics, antiviral drugs) when tested with Inf A and Inf B strains at 3x LOD.
Precision (Inter-lot variability)	Low variability between different manufacturing lots.	%CV for Inter-lot imprecision was <1.8% for Influenza A (C100: 1.6%, C95: 1.8%, C0: 0.0%). All runs from 3 lots agreed with expected results (100% agreement).
Reproducibility	High agreement across sites, operators, days, analyzers, and reagent lots.	Total Percent Agreement: ≥99.9% (Influenza A: 100% for all categories/sites, Influenza B: 100% for most, 98.9% for Flu B High Negative at one site, overall 99.9%). %CV: For Influenza A ranged between 1.3% and 3.8%. For Influenza B ranged between 1.1% and 3.4%. (Based on 720 runs across 3 sites, 2 operators per site, 5 days, 15 analyzers, 3 lots).
Fresh vs. Frozen Samples	Equivalent performance for fresh and frozen specimens.	100% detection for both fresh and frozen samples across all viral loads (Influenza A and B strains at and near LOD and clinical range), indicating equivalent performance.
Clinical Sensitivity (Influenza A)	Must demonstrate substantial equivalence to predicate.	Prospective Samples (vs. Viral Culture): 100.0% (95% CI: 89.8% - 100.0%). Retrospective Samples (vs. PCR/Sequencing): 100.0% (95% CI: 95.1% - 100.0%) - referred to as Positive Agreement.
Clinical Specificity (Influenza A)	Must demonstrate substantial equivalence to predicate.	Prospective Samples (vs. Viral Culture): 96.8% (95% CI: 94.5% - 98.1%). Retrospective Samples (vs. PCR/Sequencing): 97.1% (95% CI: 91.9% - 99.0%) - referred to as Negative Agreement.
Clinical Sensitivity (Influenza B)	Must demonstrate substantial equivalence to predicate.	Prospective Samples (vs. Viral Culture): 100.0% (95% CI: 88.6% - 100.0%). Retrospective Samples (vs. PCR/Sequencing): 100.0% (95% CI: 64.6% - 100.0%) - referred to as Positive Agreement.
Clinical Specificity (Influenza B)	Must demonstrate substantial equivalence to predicate.	Prospective Samples (vs. Viral Culture): 94.1% (95% CI: 91.3% - 96.0%). Retrospective Samples (vs. PCR/Sequencing): 99.4% (95% CI: 96.8% - 99.9%) - referred to as Negative Agreement.

2. Sample Sizes and Data Provenance for the Test Set:

Clinical Test Set Sample Size: A total of 615 clinical specimens were tested.
- Prospective Samples: 435 samples.
- Retrospective Samples: 180 samples. (One retrospective sample was excluded from analysis due to being indeterminate by PCR/sequencing and retest, making the effective count 179 for that portion of the analysis).
Data Provenance (Country of Origin and Retrospective/Prospective):
- Prospective Samples: Collected from patients with signs and symptoms of influenza in the Eastern and Southwestern US from February 12, 2009, to March 26, 2009. These are prospective samples.
- Retrospective Samples: Collected between 2008-2010, including 2009 H1N1 samples from the 2009-2010 flu season. These are retrospective samples.

3. Number of Experts and Qualifications for Ground Truth of the Test Set:

For this type of in vitro diagnostic device (IVD), ground truth is established by reference laboratory methods, not by human experts in the sense of radiologists.

For prospective samples (435 samples): The reference method (ground truth) was Viral Culture and IFA staining. These are standard laboratory techniques for influenza detection, typically performed by trained clinical laboratory personnel. The document does not specify the number of individual experts or their specific qualifications beyond the method itself.
For retrospective samples (179 samples): The reference method (ground truth) was PCR and bi-directional sequencing based on published methods (Ghedin et al. 2005; Ghedin et al. 2009; World Health Organization Sequencing Primers and Protocols, 2009). Again, this refers to established molecular diagnostic techniques performed by qualified laboratory personnel, rather than a panel of clinical experts adjudicating images or reports.

4. Adjudication Method for the Test Set:

The document describes discordant results investigation for the prospective samples:

"Discordance results were investigated using PCR and bi-directional sequencing."

This implies that if the Liat™ Assay result differed from the initial Viral Culture/IFA staining result, a third, more definitive molecular method (PCR/sequencing) was used to resolve the discrepancy and establish the "true" status of the sample. This is a common practice in IVD studies and functions as an adjudication method for discordant results.

For the retrospective samples, PCR/sequencing itself served as the primary reference method.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done:

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done.

MRMC studies typically evaluate human reader performance (e.g., radiologists interpreting images) with and without the assistance of an AI algorithm. The IQuum Liat™ Influenza A/B Assay is an automated real-time RT-PCR assay performed on an analyzer. It is an in vitro diagnostic device, not an imaging AI or a decision support system for human readers. Therefore, the concept of human readers improving with AI assistance does not apply in this context.

6. If a Standalone (Algorithm Only without Human-in-the-Loop Performance) was done:

Yes, the performance presented for the Liat™ Influenza A/B Assay is essentially standalone (algorithm only without human-in-the-loop performance).

The device is an automated in vitro diagnostic test. The Liat™ Analyzer performs all assay steps from raw sample and automatically reports results. The user adds the sample, scans barcodes, and inserts the tube, but the detection, amplification, and interpretation are done by the instrument system, not by human interpretation of raw signals. The clinical agreement section evaluates the performance of this automated system directly against the reference methods (viral culture/IFA, PCR/sequencing).

7. The Type of Ground Truth Used:

The types of ground truth used were:

Viral Culture and IFA staining: For prospective clinical samples.
PCR and bi-directional sequencing: For retrospective clinical samples, and for resolving discrepancies in prospective samples.

These are established laboratory diagnostic methods considered to be definitive for the presence of influenza viruses.

8. The Sample Size for the Training Set:

The document does not explicitly mention a "training set" size for the Liat™ Influenza A/B Assay. This is common for IVD devices based on RT-PCR; their design is based on known genetic targets, and analytical validation (LOD, reactivity, specificity) uses characterized strains and samples. "Training" in the machine learning sense is not typically applicable or detailed in such 510(k) summaries for IVD assays. The studies described are primarily for analytical and clinical validation of the final device.

9. How the Ground Truth for the Training Set Was Established:

As no "training set" in the machine learning sense is described for the Liat™ Assay, the establishment of ground truth for such a set is not detailed. However, the ground truth for all samples used in the analytical and clinical performance studies (which would serve a similar purpose of verifying performance) was established using:

Titered viruses: For Limit of Detection and Reactivity studies, the concentration of viral strains was precisely known (TCID50/mL).
Characterized pathogens/microorganisms: For Cross-Reactivity and Interference studies, specific strains/species of bacteria and viruses were used at known concentrations (CFU/mL or TCID50/mL).
Viral culture and IFA staining: For prospective human clinical samples.
PCR and bi-directional sequencing: For retrospective human clinical samples and for resolving discordant results in prospective samples.

These are all well-established, objective laboratory methods for determining the presence and type of influenza virus or other microorganisms.

Summary

{0}------------------------------------------------

$IQ^{uum}$

IQuum, Inc. 700 Nickerson Road, Marlborough, MA 01752

Tel 508 970 0099 Fax 508 970 0119 www.lQuum.com

510(K) SUMMARY

AUG - 4 2011

Applicant	IQuum, Inc.700 Nickerson RoadMarlborough, MA 01752Tel: 508-970-0099Fax: 508-970-0119
Contact	Lingjun ChenTitle: Vice President, Operations & Business DevelopmentTel: 508-970-0099 ext. 116Email: lingjun@iquum.com
Summary Date	May 16, 2011
Trade Name	Liat™ Influenza A/B Assay, Liat™ Analyzer
Common Name	Influenza A, B Panel
Regulation Number	21 CFR 866.3980
Classification Name	Respiratory Viral Panel Multiplex Nucleic Acid Assay
Predicate Device:	Cepheid Xpert® Flu Assay (K103766)

Intended Use

{1}------------------------------------------------

Device Description

Test Operation

A nasopharyngeal swab can be collected following the user institution's standard procedures. For nasopharyngeal swab samples suspended in UTM, the user transfers 100 µl of the UTM sample into Liat Influenza A/B Assay tube. The user then scans the tube barcode to identify the test and scans sample barcode to code the sample ID using the Liat Tube is then inserted into the Liat Analyzer. The analyzer performs all test steps and outputs interpreted results in 20 minutes. A report of the interpreted results can be viewed in the View Results window, and printed directly through a USB connected printer.

No reagent preparation or addition steps are required, other than adding the sample to the Liat tube. Because all the reagents are contained within the Liat assay tube and no sample or reagent needs to be removed from the tube, cross-contamination between samples is minimized.

{2}------------------------------------------------

Predicate Device Comparison

Predicate Device: Cepheid Xpert® Flu Assay (K103766)

	Device:	Predicate:
Item Name	Liat Influenza A/B	Cepheid Xpert Flu
Intended Use	The IQuum Liat™ Influenza A/B Assayperformed on the Liat™ Analyzer is anautomated multiplex real-time RT-PCRassay for the rapid in vitro qualitativedetection and discrimination ofinfluenza A virus and influenza B virusRNA in nasopharyngeal swabspecimens from patients with signs andsymptoms of respiratory infection inconjunction with clinical andepidemiological risk factors. The test isintended for use as an aid in thedifferential diagnosis of influenza A andinfluenza B in humans and is notintended to detect influenza C.Negative results do not precludeinfluenza virus infection and should notbe used as the sole basis for treatment orother patient management decisions.Conversely, positive results do not rule-out bacterial infection or co-infectionwith other viruses. The agent detectedmay not be the definite cause of disease.Performance characteristics forinfluenza A were established wheninfluenza A/H1 and A/H3 were thepredominant influenza A viruses incirculation. When other influenza Aviruses are emerging, performancecharacteristics may vary.If infection with a novel influenza Avirus is suspected based on currentclinical and epidemiological screeningcriteria recommended by public healthauthorities, specimens should becollected with appropriate infectioncontrol precautions for novel virulent	The Cepheid® Xpert Flu Assay is anautomated, multiplex real-time RT-PCR assay intended for the in vitroqualitative detection anddifferentiation of influenza A,influenza B and 2009 H1N1 influenzaviral RNA. The Xpert Flu Assay usesnasal aspirates/washes andnasopharyngeal swab specimenscollected from patients with signs andsymptoms of respiratory infection inconjunction with clinical andepidemiological risk factors. TheXpert Flu Assay is intended as an aidin the diagnosis of influenza.Negative results do not precludeinfluenza virus infection and shouldnot be used as the sole basis fortreatment or other patient managementdecisions.Performance characteristics forinfluenza A were established duringthe 2009-2010 influenza season when2009 H1N1 influenza was thepredominant influenza A virus incirculation. When other influenza Aviruses are emerging, performancecharacteristics may vary.If infection with a novel influenza Avirus is suspected based on currentclinical and epidemiological screeningcriteria recommended by public healthauthorities, specimens should becollected with appropriate infectioncontrol precautions for novel virulentinfluenza viruses and sent to state orlocal health department for testing.Viral culture should not be attempted in these cases unless a BSL 3+ facility

	cases unless a BSL 3+ facility is
	available to receive and culture
	specimens.
	Device:	Predicate:
Item Name	Liat Influenza A/B	Cepheid Xpert Flu
Regulation	21 CFR 866.3980	21 CFR 866.3332
Product Code	OCC, OOI	OQW, OCC, OOI
Assay Target	Influenza AInfluenza B	Influenza AInfluenza BInfluenza A subtype 2009 H1N1
Sample Type	Nasopharyngeal Swab	Nasopharyngeal SwabNasal aspirates/washes
Internal Control	Yes	Yes
Influenza A ViralTarget	Matrix gene	Matrix gene
Influenza B ViralTarget	Non-structural protein (NSP) gene	Hemagglutinin gene
Assay Instrument	LiatTM Analyzer	GeneXpert instruments
Self-containedSystem	Integrated PC, software, and touch-screen display	External PC computer and softwarefor running tests and viewing theresults
All AssayReagentsContained inDisposable	No manual reagent addition required	Requires manual dispensing ofBinding Reagent into the chamberwith the small opening of the XpertFlu Assay Cartridge
Automated Assay	Yes, sample preparation, amplification,detection and result interpretation	Yes, sample preparation,amplification, detection and resultinterpretation
Extraction Method	Sample preparation integrated in Liat Tubeand Liat Analyzer	Sample preparation integrated inGeneXpert Cartridge and GeneXpertInstrument
Assay Method	RT-PCR for detecting the presence /absence of viral RNA in clinicalspecimens	RT-PCR for detecting the presence /absence of viral RNA in clinicalspecimens
DetectionTechnique	Multiplex assay using different reporterdyes for each target	Multiplex assay using differentreporter dyes for each target
ResultInterpretation	Automated	Automated
Assay Result	Qualitative	Qualitative
Laboratory Users	CLIA moderate complexity and highcomplexity laboratory	CLIA moderate complexity and highcomplexity laboratory
Time-to-result	~20 minutes	~75 minutes

{3}------------------------------------------------

{4}------------------------------------------------

Substantial Equivalence

Limit of Detection

The Limit of Detection (LOD) of the Liat Influenza A/B Assay was tested using 3 strains of Influenza A (A/Brisbane/10/2007, A/Brisbane/59/2007, and A/NY/01/2009) and 2 strains of Influenza B (B/Malaysia/2506/04 and B/Florida/04/06). The LOD was determined by limiting dilution studies using these titered viruses. The viruses were spiked into nasopharyngeal swab (NPS) sample matrix, and then tested using the Liat Influenza A/B Assay. The LOD was determined as the lowest log virus concentration that was detected ≥95% of the time (i.e. log concentration at which at least 19 out of 20 replicates tested positive). The LOD for 3 strains of Influenza A were 102 to 101 TCID50/mL, while those for the 2 strains of Influenza B were 103 to 10" TCID50/mL.

Virus Strain	LOD (TCID50/mL)
A/Brisbane/10/2007	10-1
A/Brisbane/59/2007	10-2
A/NY/01/2009	10-1
B/Florida/04/06	10-1
B/Malaysia/2506/04	10-3

Reactivity

Reactivity study evaluates the ability of the Liat Influenza A/B Assay to detect influenza strains representing temporal and geographical diversity. The Liat Influenza A/B Assay was evaluated for reactivity with 22 Influenza A strains and 10 Influenza B strains. Influenza A strains included 8 seasonal Influenza A/H1 strains, 8 seasonal Influenza A/H3 strains, 3 Influenza A 2009 H1N1 strains, 3 swine origin Influenza A strains. The Liat Influenza A/B Assay detected all strains tested.

Influenza Strain	Type / Subtype	TestConcentration	Inf AResult	Inf BResult	Viral/Bacterial pathogen	Test concentration	Inf A Result	Inf B Result	Pathogen	PathogenConcentration	A/Brisbane/59/07Inf A Result	A/Brisbane/59/07Inf B Result	B/Malaysia/2506/04Inf A Result	B/Malaysia/2506/04Inf B Result
A/Brisbane/59/2007	Influenza A, seasonal H1	8.0× $10-3$ TCID50/mL	+	-	Adenovirus Type 1	8.9×105 TCID50/mL	-	-	Adenovirus Type 1	$8.9 \times 10^5$ TCID50/mL	+	-	-	+
A/New Caledonia/20/99	Influenza A, seasonal H1	1.0× $102$ TCID50/mL	+	-	Adenovirus Type 7	4.5×104 TCID50/mL	-	-	Adenovirus Type 7	$4.5 \times 10^4$ TCID50/mL	+	-	-	+
A/Solomon Island/3/2006	Influenza A, seasonal H1	5.0× $10-2$ TCID50/mL	+	-	Human Coronavirus 229E	1.4×103 TCID50/mL	-	-	Human Coronavirus 229E	$1.4 \times 10^3$ TCID50/mL	+	-	-	+
A/Mal/302/54	Influenza A, seasonal H1	1.0× $103$ TCID50/mL	+	-	Human Coronavirus OC43	7.9×104 TCID50/mL	-	-	Human Coronavirus OC43	$7.9 \times 10^4$ TCID50/mL	+	-	-	+
A/Denver/1/57	Influenza A, seasonal H1	5.0× $102$ TCID50/mL	+	-	Enterovirus	1×105 TCID50/mL	-	-	Enterovirus	$1 \times 10^5$ TCID50/mL	+	-	-	+
A/FM/1/47	Influenza A, seasonal H1	1.0× $102$ TCID50/mL	+	-	Human Parainfluenza Type 1	2.8×103 TCID50/mL	-	-	Human Parainfluenza Type 1	$2.8 \times 10^3$ TCID50/mL	+	-	-	+
A/PR/8/34	Influenza A, seasonal H1	2.5× $101$ TCID50/mL	+	-	Human Parainfluenza Type 2	1.4×105 TCID50/mL	-	-	Human Parainfluenza Type 2	$1.4 \times 10^5$ TCID50/mL	+	-	-	+
A/Weiss/43	Influenza A, seasonal H1	2.5× $103$ TCID50/mL	+	-	Human Parainfluenza Type 3	1.6×105 TCID50/mL	-	-	Human Parainfluenza Type 3	$1.6 \times 10^5$ TCID50/mL	+	-	-	+
A/Brisbane/10/2007	Influenza A, seasonal H3	1.0× $10-1$ TCID50/mL	+	-	Measles	7.9×104 TCID50/mL	-	-	Measles	$7.9 \times 10^4$ TCID50/mL	+	-	-	+
Influenza Strain	Type / Subtype	Test Concentration	Inf A Result	Inf B Result	Human Metapneumovirus	7×103 TCID50/mL	-	-	Human Metapneumovirus	$7 \times 10^3$ TCID50/mL	+	-	-	+
A/Alice	Influenza A, seasonal H3	5.0× $10^1$ TCID50/mL	+	-	Mumps virus	7.9×104 TCID50/mL	-	-	Mumps virus	$7.9 \times 10^4$ TCID50/mL	+	-	-	+
A/MRC2	Influenza A, seasonal H3	1.0× $10^2$ TCID50/mL	+	-	Respiratory syncytial virus type B	1.4×104 TCID50/mL	-	-	Respiratory syncytial virus type B	$1.4 \times 10^4$ TCID50/mL	+	-	-	+
A/Hong Kong/8/68	Influenza A, seasonal H3	2.0× $10^1$ TCID50/mL	+	-	Rhinovirus Type 1A	1.6×105 TCID50/mL	-	-	Rhinovirus Type 1A	$1.6 \times 10^5$ TCID50/mL	+	-	-	+
A/Victoria/3/75	Influenza A, seasonal H3	2.5× $10^1$ TCID50/mL	+	-	Cytomegalovirus	4.5×104 TCID50/mL	-	-	Cytomegalovirus	$4.5 \times 10^4$ TCID50/mL	+	-	-	+
A/Wisconsin/67/05	Influenza A, seasonal H3	5.0× $10^1$ TCID50/mL	+	-	Epstein Barr virus	1.9×105 copies/mL	-	-	Epstein Barr virus	$1.9 \times 10^5$ copies/mL	+	-	-	+
A/Port Chalmers/1/73	Influenza A, seasonal H3	5.0× $10^2$ TCID50/mL	+	-	Bordetella pertussis	1.8×105 CFU/mL	-	-	Bordetella pertussis	$1.8 \times 10^5$ CFU/mL	+	-	-	+
A/Aichi/2/68	Influenza A, seasonal H3	2.0× $10^2$ CEID50/mL	+	-	Chlamydia pneumoniae	8×104 TCID50/mL	-	-	Chlamydia pneumoniae	$8 \times 10^4$ TCID50/mL	+	-	-	+
A/NY/01/2009	Influenza A, 2009 H1N1	1.0× $10^1$ TCID50/mL	+	-	Corynebacterium sp.	5.0×106 CFU/mL	-	-	Corynebacterium sp.	$5.0 \times 10^6$ CFU/mL	+	-	-	+
A/NY/02/2009	Influenza A, 2009 H1N1	2.5× $10^2$ TCID50/mL	+	-	Escherichia coli	6.6×106 CFU/mL	-	-	Escherichia coli	$6.6 \times 10^6$ CFU/mL	+	-	-	+
A/NY/03/2009	Influenza A, 2009 H1N1	4.0× $10^1$ TCID50/mL	+	-	Haemophilus influenzae	3×106 CFU/mL	-	-	Haemophilus influenzae	$3 \times 10^6$ CFU/mL	+	-	-	+
A/New Jersey/8/76	Influenza A, H1N1 non 2009	1.0× $10^1$ TCID50/mL	+	-	Lactobacillus sp.	1.6×106 CFU/mL	-	-	Lactobacillus sp.	$1.6 \times 10^6$ CFU/mL	+	-	-	+
A/Swine/1976/31	Influenza A, H1N1 non 2009	2.0× $10^1$ TCID50/mL	+	-	Legionella pneumophila	7×106 CFU/mL	-	-	Legionella pneumophila	$7 \times 10^6$ CFU/mL	+	-	-	+
A/Swine/lowa/15/30	Influenza A, H1N1 non 2009	2.0× $10^2$ TCID50/mL	+	-	Moraxella catarrhalis	5.8×106 CFU/mL	-	-	Moraxella catarrhalis	$5.8 \times 10^6$ CFU/mL	+	-	-	+
B/Florida/04/06	Influenza B	8.0× $10^{-2}$ TCID50/mL	-	+	Neisseria meningitidis	3.2×106 CFU/mL	-	-	Neisseria meningitidis	$3.2 \times 10^6$ CFU/mL	+	-	-	+
B/Malaysia/2506/04	Influenza B	2.0× $10^{-3}$ TCID50/mL	-	+	Neisseria sp.	1.8×106 CFU/mL	-	-	Neisseria sp.	$1.8 \times 10^6$ CFU/mL	+	-	-	+
B/Florida/7/04	Influenza B	5.0× $10^{-2}$ TCID50/mL	-	+	Pseudomonas aeruginosa	1.6×106 CFU/mL	-	-	Pseudomonas aeruginosa	$1.6 \times 10^6$ CFU/mL	+	-	-	+
B/Allen/45	Influenza B	5.0× $10^1$ CEID50/mL	-	+	Staphylococcus aureus	4.5×106 CFU/mL	-	-	Staphylococcus aureus	$4.5 \times 10^6$ CFU/mL	+	-	-	+
B/GL/1739/54	Influenza B	2.0× $10^1$ TCID50/mL	-	+	Staphylococcus epidermidis	6×106 CFU/mL	-	-	Staphylococcus epidermidis	$6 \times 10^6$ CFU/mL	+	-	-	+
B/Taiwan/2/62	Influenza B	5.0× $10^{-2}$ TCID50/mL	-	+	Streptococcus pneumoniae	1.9×106 CFU/mL	-	-	Streptococcus pneumoniae	$1.9 \times 10^6$ CFU/mL	+	-	-	+
B/Maryland/1/59	Influenza B	5.0× $10^3$ TCID50/mL	-	+	Streptococcus pyogenes	3.7×106 CFU/mL	-	-	Streptococcus pyogenes	$3.7 \times 10^6$ CFU/mL	+	-	-	+
B/Mass/3/66	Influenza B	1.0× $10^1$ TCID50/mL	-	+	Streptococcus salivarius	4.3×106 CFU/mL	-	-	Streptococcus salivarius	$4.3 \times 10^6$ CFU/mL	+	-	-	+
B/HongKong/5/72	Influenza B	2.5× $10^1$ TCID50/mL	-	+
B/Lee/40	Influenza B	1.0× $10^0$ TCID50/mL	-	+

{5}------------------------------------------------

{6}------------------------------------------------

Cross Reactivity

Cross reactivity study evaluates the Liat Influenza A/B Assay's potential cross-reactivity with non-influenza respiratory pathogens and other microorganisms with which the majority of the population may have been infected. The Liat assay was evaluated against a panel of 31 human pathogens. Bacteria were tested at 10-106 CFU/mL. Viruses were tested at 103-105 TCID56/mL. The Liat Influenza A/B Assay showed no cross reactivity for the tested organisms.

{7}------------------------------------------------

Inhibition by other Microorganisms

Interfering microorganism study evaluates whether non-influenza respiratory pathogens and other microorganisms with which the majority of the population may have been infected can interfere in the detection of Influenza A or B by the Liat assay. The panel of 31 human pathogens tested in the cross-reactivity study was tested for potential interference. Bacteria were tested at 10-106 CFU/mL and viruses were tested at 103-105 TCID50/mL in the presence of either A/Brisbane/59/2007 or B/Malaysia/2506/04 at 3x LOD concentration in negative NPS matrix. Results show that the presence of the tested microorganisms did not interfere with the detection of Inf A or Inf B.

{8}------------------------------------------------

Interfering Substances

The Liat Influenza A/B Assay was evaluated with potentially interfering substances that may be encountered in respiratory specimens. Medically and/or physiologically relevant concentrations of potential interferents were tested with 2 influenza A strains and 2 influenza B strains at 3x LOD (10-10-2 TCID50/mL). Results showed that substances tested did not interfere in the detection of influenza A and B strains.

Potential Interferent	Active Ingredient	Concentration.
MucinBovine submaxillary gland, type I-S	Purified mucin protein	0.1 mg/ml and25 mg/ml
Blood	-	5% (v/v)
Nasal spray - Afrin	Oxymetazoline	5% (v/v)
Nasal corticosteroids - Veramyst	Fluticasone	5% (v/v)
Nasal gel – Zicam	Galphimia glauca, Histaminumhydrochloricum, Luffa operculata, Sulphur	5% (v/v)
Throat lozenges, oral anesthetic andanalgesic - Cepacol	Benzocaine, Menthol	5 mg/ml
Antibiotic, nasal ointment - Bactroban	Mupirocin	5 mg/ml
Antiviral drug – Relenza	Zanamivir	5 mg/ml
Antiviral drug - Tamiflu	Oseltamivir	7.5 mg/ml
Antimicrobial, systemic	Tobramycin	4 µg/ml

Inter-lot Precision

Inter-lot precision assesses the Liat tube manufacturing process as a potential source of assay variability. Three lots of Liat Influenza Assay tubes were tested with 1 Influenza A strain at C95 (LOD, n=180), C100 (4xLOD, n=60) and C0 (negative NPS matrix, n=60). Results from all runs agreed with expected results. Imprecision in Ct from inter-lot variability was <1.8%.

Inf A	n	%Agreement	Avg Ct	StdevInter-lot	%CVInter-lot
C100	60	100%	29.6	0.49	1.6%
C95	180	100%	32.0	0.59	1.8%
CO	60	100%	42.0	0.00	0.0%

Reproducibility

Reproducibility study assesses the total variability of the Liat Influenza A/B Assay across operators, study sites, testing days. Liat Analyzers, and Liat assay tube lots. The Liat assay was evaluated at 3 sites, including 2 CLIA waived sites. Two operators at each of the 3 sites tested an 8 member reproducibility panel in triplicate on 5 different days, for a total of 720 runs (8 panel members × 3 replicates × 2 operators × 5 days × 3 sites). Fifteen (15) Liat Analyzers and 3 Liat Influenza A/B Assay tube lots were used. The reproducibility panel comprises a high negative, a low positive and a medium positive of each of Influenza A and B, and the assay positive and negative controls. Percent agreement with expected result, mean Ct, and Ct %CV for each site are show in tables below. %CV for Influenza A ranged between 1.3% and 3.8% and that for Influenza B ranged between 1.1% and 3.4%. Total percent agreement was ≥99.9%.

{9}------------------------------------------------

	Site 1			Site 2			Site 3			Total
Sample	Agree-ment w/expectedresult	AvgCt	Total%CV	Agree-ment w/expectedresult	AvgCt	Total%CV	Agree-ment w/expectedresult	AvgCt	Total%CV	Agree-ment w/expectedresult	95% CI
PositiveControl	30/30	32.0	1.4%	30/30	32.0	2.2%	30/30	31.5	1.3%	90/90(100%)	95.9%-100.0%
NegativeControl	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu A HighNegative	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu A LowPositive	30/30	32.1	3.8%	30/30	32.0	2.1%	30/30	31.8	1.8%	90/90(100%)	95.9%-100.0%
Flu A Med.Positive	30/30	29.9	2.0%	30/30	29.6	2.0%	30/30	29.3	1.9%	90/90(100%)	95.9%-100.0%
Flu B HighNegative	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu B LowPositive	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu B Med.Positive	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
TotalAgreement	240/240 (100%)			240/240 (100%)			240/240 (100%)			720/720(100%)	99.5%-100.0%

Influenza A Reproducibility

Influenza B Reproducibility

	Site 1			Site 2			Site 3			Total
Sample	Agree-ment w/expectedresult	AvgCt	Total%CV	Agree-ment w/expectedresult	AvgCt	Total%CV	Agree-ment w/expectedresult	AvgCt	Total%CV	Agree-ment w/expectedresult	95% Cl
PositiveControl	30/30	31.2	1.5%	30/30	31.0	2.2%	30/30	30.6	1.1%	90/90(100%)	95.9%-100.0%
NegativeControl	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu A HighNegative	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu A LowPositive	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu A Med.Positive	30/30	39.0	0.0%	30/30	39.0	0.0%	30/30	39.0	0.0%	90/90(100%)	95.9%-100.0%
Flu B HighNegative	30/30	39.0	0.0%	29/30	38.9	1.7%	30/30	39.0	0.0%	89/90(98.9%)	94.0%-99.8%
Flu B LowPositive	30/30	31.3	2.3%	30/30	31.0	3.4%	30/30	30.9	1.7%	90/90(100%)	95.9%-100.0%
Flu B Med.Positive	30/30	29.4	2.6%	30/30	29.5	3.0%	30/30	28.6	3.3%	90/90(100%)	95.9%-100.0%
TotalAgreement	240/240 (100%)			239/240 (99.6%)			240/240 (100%)			719/720(99.9%)	99.2%-100.0%

{10}------------------------------------------------

Performance using Fresh vs. Frozen Samples

The Liat Influenza A/B Assay was tested by comparing its performance using fresh and frozen specimens. One influenza A strain and one influenza B strain were individually spiked into NPS matrix at different viral loads, including levels near LOD and levels reflecting the clinical range. For each strain, 60 samples were tested immediately while another 60 samples were frozen at -80°C for 7 days, thawed and then tested. Fresh and frozen samples demonstrated 100% detection across all levels of viral load, demonstrating that the Liat Influenza A/B Assay had equivalent performance for fresh and frozen samples.

Clinical Agreement

Three sites participated in the clinical study for the Liat Influenza A/B Assay. A total of 615 clinical specimens were tested including 435 prospectively collected samples and 180 retrospective samples. Prospective samples were collected from patients with signs and symptoms of influenza in the Eastern and Southwestern US from 12 February 2009 to 26 March 2009. Viral culture and IFA staining was used as the reference method for these prospectively collected samples. Discordance results were investigated using PCR and bi-directional sequencing.

Due to the low prevalence of influenza during the collection period as well as the subsequent emergence of the 2009 H1N1 virus, retrospective samples collected between 2008-2010, including 2009 H1N1 samples from the 2009-2010 flu season, were tested. Reference testing for these samples was performed by PCR and bi-directional sequencing based on published methods (Ghedin et al. 2005; Ghedin et al. 2009; World Health Organization Sequencing Primers and Protocols, 2009). Of the 180 samples, 1 sample was indeterminate by PCR/sequencing, and remained indeterminate upon retest; this sample was excluded from the analysis.

Clinical sample testing was performed at 3 sites in April-May 2011 using 30 Liat Analyzers in total. Tables below summarize the clinical performance of the Liat Influenza A/B Assay.

	Viral Culture
Influenza A	Positive	Negative	Total
Liat	Positive	34	13a	47
	Negative	0	388	388
	Total	34	401	435

	Liat Influenza A/B Assay Clinical Performance – Prospective Samples
--	---------------------------------------------------------------------	--

	%	95% CI
Sensitivity	100.0%	(89.8% - 100.0%)
Specificity	96.8%	(94.5% - 98.1%)

a Of 13 false positive samples, 8 were Influenza A positive by PCR/sequencing, 4 were negative by PCR/sequencing, and 1 was indeterminate by PCR/sequencing due to low sequence quality score.

Influenza B		Viral Culture
		Positive	Negative	Total
Liat	Positive	30	24b	54
	Negative	0	381	381
	Total	30	405	435

	%	95% Cl
Sensitivity	100.0%	(88.6% - 100.0%)
Specificity	94.1%	(91.3% - 96.0%)

b Of 24 false positive samples, 13 were Influenza B positive by PCR/sequencing, 3 were negative by PCR/sequencing, and 8 samples were indeterminate by PCR/sequencing due to low sequence

{11}------------------------------------------------

quality score.

Liat Influenza A/B Assay Clinical Performance - Retrospective Samples

Influenza A		PCR/Sequencing
		Positive	Negative	Total
Liat	Positive	74c	3	77
	Negative	0	102	102
	Total	74	105	179

	%	95% CI
PositiveAgreement	100.0%	(95.1% - 100.0%)
NegativeAgreement	97.1%	(91.9% - 99.0%)

^ Of 74 Influenza A positive retrospective samples, 44 were 2009 H1N1 positive, and 20 were A/H3 positive by PCR/sequencing. The 10 remaining samples were verified to be Influenza A however, no further subtyping analysis was done.

Influenza B		PCR/Sequencing
		Positive	Negative	Total
Liat	Positive	7	1	8
	Negative	0	171	171
	Total	7	172	179

	%	95% CI
PositiveAgreement	100.0%	(64.6% - 100.0%)
NegativeAgreement	99.4%	(96.8% - 99.9%)

Conclusion

The results of the analytical and clinical performance studies submitted in this premarket notification are complete and demonstrate that the Liat Influenza A/B assay on the Liat Analyzer are substantially equivalent to the predicate device.

{12}------------------------------------------------

Image /page/12/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of two main elements: a circular text element and an emblem. The text element reads "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged in a circular fashion. The emblem is a stylized representation of a bird-like figure, with flowing lines suggesting wings or movement.

Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993

IQuum Inc. c/o Lingjun Chen Vice President, Operations and Business Development 700 Nickerson Road Marlborough, MA 01752

AUG - 4 2011

Re: K111387

Trade/Device Name: Liat Influenza A/B Assay, Liat Analyzer Regulation Number: 21 CFR§ 866.3980 Regulation Name: Respiratory Viral Panel Multiplex Nucleic Acid Assay Regulatory Class: Class II Product Code: OCC. OOI Dated: May 16, 2011 Received: May 18, 2011

Dear Dr. Chen:

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

If your device is classified (see above) into class II (Special Controls), 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); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). This letter will allow you to begin marketing your device as described in your Section 510(k) premarket

{13}------------------------------------------------

Page 2 - Lingjun Chen

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 Parts 801 and 809), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 796-5450. 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/ReportalProblem/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 Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.

Sincerely yours.

Hay atoyns

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

{14}------------------------------------------------

Indications for Use

510(k) Number (if known): K111387

Device Name: Liat™ Influenza A/B Assay, Liat™ Analyzer

Indications for Use:

Prescription Use _____________________________________________________________________________________________________________________________________________________________ (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 IF NEEDED)

Concurrence of CDRH, Office of In Vitro Diagnostics (OIVD)

Tamar Feldblum
Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

Page 1 of 1

510(k) K///3827

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.