K Number

Device Name

Manufacturer

Cepheid

Date Cleared

2024-06-27

(72 days)

Product Code

Regulation Number

Type

Panel

Reference & Predicate Devices

N/A

Predicate For

N/A

Intended Use

The Xpert HCV test, performed on the GeneXpert Xpress System, is an automated in vitro reverse transcription polymerase chain reaction (RT-PCR) test for the qualitative detection of hepatitis C virus (HCV) RNA in human fingerstick K2-EDTA whole blood from adult individuals at risk and/or with signs and symptoms of HCV infection with or without antibody evidence of HCV infection. Detection of HCV RNA indicates that the virus is replicating and therefore is evidence of active infection. Detection of HCV RNA does not discriminate between acute and chronic states of infection.

The Xpert HCV test is not intended for monitoring patients undergoing treatment or for use in screening blood, plasma, or tissue donors.

Device Description

The Xpert HCV test, is an automated qualitative in vitro reverse transcription polymerase chain reaction (RT-PCR) test. The Xpert HCV test is performed on the GeneXpert Xpress System. With this system an operator can run the test by performing four steps: 1) mix the specimen. 2) transfer the liquid sample to the cartridge with a transfer pipette, 3) run the test on the instrument, and 4) read the results.

The GeneXpert Xpress System (Hub configuration) consists of a GeneXpert IV instrument that conducts the sample preparation, nucleic acid amplification and real-time fluorescent signal detection for the test, and a GeneXpert Hub with preloaded GeneXpert Xpress software for running the tests and viewing the results. The GeneXpert Hub accessory integrates the computer, touchscreen monitor and barcode scanner. Each of the GeneXpert modules in the GeneXpert IV instrument can perform separate sample preparation and testing. The module contains a syringe drive for dispensing fluids (i.e., the syringe drive activates the plunger that works in concert with the rotary valve in the cartridge to move fluids between chambers), an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE (Intelligent Cooling/Heating Optical Reaction) thermocycler for performing real-time PCR and RT-PCR and detection.

The Xpert HCV test requires the use of a single-use disposable GeneXpert cartridge that contains all necessary reagents for the detection of HCV RNA. Because the cartridges are self-contained, the risk of cross-contamination between samples is minimized. The Xpert HCV test includes reagents for the detection of HCV RNA in clinical specimens as well as a sample processing control (SPC) and internal control high (IC-H) used to control for adequate processing of the target and to monitor the presence of inhibitor(s) in the RT and PCR reactions. The Probe Check Control (PCC) verifies reagent rehydration. PCR tube filling in the cartridge, probe integrity, and dye stability. The Sample Volume Adequacy (SVA) control ensures the sample was correctly added to the cartridge and verifies that the correct volume of sample has been added to the sample chamber.

The Xpert HCV test is designed for use with human K2-fingerstick EDTA whole blood. The BD Microtainer for capillary whole blood collection was validated for use with the Xpert HCV test. After collecting human fingerstick EDTA whole blood in the BD Microtainer, a 100μl aliquot of the specimen is transferred to the sample chamber of the Xpert HCV cartridge using the transfer pipette supplied in the Xpert HCV kit.

The sample results are interpreted by the GeneXpert Xpress System from measured fluorescent signals and embedded calculation algorithms and are shown in the View Results window. It also reports if the test has encountered an instrument error or produces no result and needs to be repeated.

AI/ML Overview

This document describes the evaluation of the Xpert HCV test for an automatic Class III designation. The test is an automated qualitative reverse transcription polymerase chain reaction (RT-PCR) test for the qualitative detection of hepatitis C virus (HCV) RNA.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for the Xpert HCV test are implied by the reported performance in both analytical and clinical studies. For analytical performance, the agreement rates for precision and reproducibility are presented. For clinical performance, Positive Percent Agreement (PPA) and Negative Percent Agreement (NPA) compared to a Patient Infected Status (PIS) algorithm are key metrics.

Acceptance Criteria (Implied)	Reported Device Performance
Analytical Performance
Precision Percent Agreement (e.g., for 1.5x LoD and 3.0x LoD)	Range: 95.0% - 100% (Table 2, Precision Study)
Reproducibility Percent Agreement (e.g., for 1.5x LoD and 3.0x LoD)	Range: 96.7% - 100% (Table 4, Multi-Site Reproducibility)
Analytical Specificity: No cross-reactivity with common organisms	None of 27 tested organisms showed cross-reactivity.
Interference: No interference from common endogenous/exogenous substances or autoimmune conditions	None of the tested substances or conditions interfered.
Limit of Detection (LoD)	Genotype 1a: 35.0 IU/mL; Genotype 1b: 41.5 IU/mL; etc. (Table 10)
Non-determinate rate	Initial: 6.0%; Overall (after retest): 1.2%
Clinical Performance
Positive Percent Agreement (PPA)	93.44% (95% CI: 87.59% – 96.64%) (Table 14)
Negative Percent Agreement (NPA)	99.77% (95% CI: 99.16% – 99.94%) (Table 14)

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

Precision Study Test Set: The precision study used a total of 60 replicates per panel member (e.g., negative, GT1a 1.5x LoD, etc.). The study was conducted in a blinded and randomized manner.
Multi-Site Reproducibility Study Test Set: A total of 90 replicates per panel member were tested across three sites. The study was blinded and randomized.
Clinical Study Test Set: 1,012 fingerstick whole blood (FS) specimens were initially collected. After exclusions due to protocol deviations, unresolved non-determinate results, and non-evaluable comparator test results, 982 FS samples were included in the performance calculations (Table 13, 14).
Non-Viral Hepatitis Samples Study: 78 FS samples from individuals with non-viral hepatitis were included, with 68 being evaluable for performance comparison (Table 15).
Data Provenance for Clinical Study: Prospective, all-comers blinded clinical study conducted at 15 CLIA waived sites located in the US.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

The document does not specify the number or qualifications of experts used to establish the ground truth for the test set. Instead, it states that the "patient infected status (PIS) algorithm based on results from an FDA approved HCV RNA test and an antibody test" served as the comparator/ground truth for the clinical study. This implies that the ground truth was established by the performance of these approved reference tests, rather than by a panel of human experts directly reviewing the samples.

4. Adjudication Method for the Test Set

The document does not describe an explicit adjudication method (e.g., 2+1, 3+1) involving human experts for the test set. The clinical study's ground truth was established by comparing the Xpert HCV test results to the "patient infected status (PIS) algorithm based on results from an FDA approved HCV RNA test and an antibody test." Any discrepancies would likely be resolved by the established reference method rather than expert adjudication of the fingerstick samples themselves. The retesting of "Two (2) specimens (1 false positive and 1 false negative) with suspicion of specimen handling and testing errors" suggests a method for investigating discrepancies, but not a general expert adjudication for all cases.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

A Multi-Reader Multi-Case (MRMC) comparative effectiveness study comparing human readers with and without AI assistance was not done. This device is an automated qualitative RT-PCR test, and its output (HCV DETECTED/NOT DETECTED) is a direct result from the instrument, not interpreted by human readers in the traditional sense that an AI would assist. The "operators" mentioned in the analytical studies are those performing the physical test steps, not interpreting diagnostic images or complex medical data.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done

Yes, a standalone performance evaluation was done. The Xpert HCV test is an automated system where the "sample results are interpreted by the GeneXpert Xpress System from measured fluorescent signals and embedded calculation algorithms" and results are "displayed in the View Results window." The clinical study (Section VI.C.3) directly evaluates the performance of this automated system against the patient infected status algorithm. The operators in the study are described as "untrained," further emphasizing the standalone nature of the device's interpretation.

7. The Type of Ground Truth Used

The ground truth used for the clinical study was the Patient Infected Status (PIS) algorithm, which was "based on results from an FDA approved HCV RNA test and an FDA approved HCV antibody test." This constitutes a form of established clinical diagnosis reference standard (or "outcomes data" in a broader sense of established clinical status).

8. The Sample Size for the Training Set

The document does not specify a sample size for a training set. As an RT-PCR diagnostic device, the "training" of the device involves the internal development and calibration of the assay (e.g., primer and probe design, thermal cycling conditions, fluorescent signal thresholds, embedded calculation algorithms) by the manufacturer based on analytical studies and known HCV characteristics, rather than a classical machine learning training phase on a large clinical dataset.

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

Since no explicit training set is mentioned in the context of machine learning, there is no description of how ground truth for a training set was established. The development of the assay likely involved extensive analytical studies (e.g., determining LoD for various genotypes, specificity, interference) using well-characterized HCV strains and clinical samples to establish the assay's performance parameters and the embedded algorithms' decision rules. These characterization efforts would form the basis of the device's "knowledge," but it's not a "training set" in the sense of supervised learning for an AI algorithm that learns from labeled data.

Summary

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EVALUATION OF AUTOMATIC CLASS III DESIGNATION FOR Xpert HCV; GeneXpert Xpress System DECISION SUMMARY

I Background Information:

A De Novo Number

DEN240016

B Applicant

Cepheid

C Proprietary and Established Names

Xpert HCV; GeneXpert Xpress System

D Regulatory Information

ProductCode(s)	Classification	RegulationSection	Panel
SBP	Class II	21 CFR 866.3171 - Simplepoint-of-care nucleic acid-based hepatitis C virusribonucleic acid test	MI - Microbiology

II Submission/Device Overview:

A Purpose for Submission:

De Novo request for evaluation of automatic class III designation for Xpert HCV test and GeneXpert Xpress System.

B Measurand:

Hepatitis C Virus RNA in human fingerstick whole blood.

C Type of Test:

Automated qualitative reverse transcription polymerase chain reaction (RT-PCR).

III Indications for Use:

Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993-0002

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A Intended Use(s):

The Xpert HCV test is not intended for monitoring patients undergoing treatment or for use in screening blood, plasma, or tissue donors.

B Indication(s) for Use:

See Intended Use above.

C Special Conditions for Use Statement(s):

Rx - For Prescription Use Only

D Special Instrument Requirements:

GeneXpert Xpress System

IV Device/System Characteristics:

A Device Description:

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control (SPC) and internal control high (IC-H) used to control for adequate processing of the target and to monitor the presence of inhibitor(s) in the RT and PCR reactions. The Probe Check Control (PCC) verifies reagent rehydration. PCR tube filling in the cartridge, probe integrity, and dye stability. The Sample Volume Adequacy (SVA) control ensures the sample was correctly added to the cartridge and verifies that the correct volume of sample has been added to the sample chamber.

Materials Provided in the Xpert HCV Test:

The Xpert HCV test Kit contains sufficient cartridges to process 10 patients or quality control samples. Each kit contains the following:

Xpert HCV cartridges with integrated reaction tubes	10 per kit
• Bead 1, Bead 2 and Bead 3 (freeze-dried)	1 of each per cartridge
• Lysis Reagent (Guanidinium Thiocyanate)	1.0 mL per cartridge
• Rinse Reagent	0.5 mL per cartridge
• Binding Reagent	1.5 mL per cartridge
• Elution Reagent	1.5 mL per cartridge
Disposable 100 µL Transfer Pipettes	20 per kit
Instructions for Use(For use with the GeneXpert Xpress System)	1 per kit
Quick Reference Instructions(For use with the GeneXpert Xpress System)	1 per kit
CD• Assay Definition File (ADF)	1 per kit

Instructions to import ADF into GenXpert Xpress System

Material required but not provided with the kit:

GeneXpert Xpress System (catalog number: GXIV-2-CLIA or GXIV-4-CLIA): ● GeneXpert Hub with integrated computer running proprietary GeneXpert Xpress software version 6.4a or higher, touchscreen monitor and barcode scanner, external CD drive, Getting Started Guide, and GeneXpert Xpress System User's Guide.
High-flow lancet or equivalent (2 mm minimum depth, capable of yielding at least 250 ● uL of capillary whole blood). Please note that sample collection might be difficult in individuals with callused fingers, and a deeper lancet might be needed.
. EDTA-containing capillary collection tubes for small volumes (K2 EDTA microtainer BD part number: 365974).

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NAT troll Hepatitis C Virus Positive and Negative controls ●
Alcohol wipes ●
Gauze pad ●
Bandage ●
Warm pack

B Principle of Operation

The Xpert HCV test, performed on the GeneXpert Xpress System, is an automated qualitative in vitro reverse transcription polymerase chain reaction (RT-PCR) test for the detection of hepatitis C Virus (HCV) RNA in human K2-EDTA fingerstick whole blood. The Xpert HCV test singleuse disposable cartridge includes reagents for the detection of HCV RNA in clinical specimens as well as a sample processing control (SPC), internal control high (IC-H), the Probe Check Control (PCC), and the Sample Volume Adequacy (SVA). After collecting human K2-EDTA fingerstick whole blood in the BD Microtainer, a 100ul aliquot of the specimen is transferred to the sample chamber of the Xpert HCV cartridge using the transfer pipette supplied in the Xpert HCV kit. The cartridge is loaded onto the GeneXpert Xpress System platform. The instrument then performs automated sample processing followed by amplification, detection, and reporting of results. The Xpert HCV test uses three channels to detect target organism and two internal controls (SPC and IC-H). The results are interpreted automatically by the GeneXpert Xpress System from measured fluorescent signals and embedded calculation algorithms. The GeneXpert Xpress System displays results in the View Results window. It also reports if the test has encountered an instrument error or produces no result and needs to be repeated. Test results are obtained in approximately 56 minutes.

Result	Interpretation
HCV DETECTED	HCV RNA is detected
HCV NOT DETECTED	HCV RNA is not detected.
NO RESULT - REPEATTEST	If the result is NO RESULT - REPEAT TEST, then retestwith a new cartridge using a new transfer pipette.*
INSTRUMENT ERROR	Result is an instrument error. Touch CLEAR ERROR andfollow the on-screen instructions. When the Home screenappears, repeat the test using a new cartridge and a newtransfer pipette.*

Table 1. Xpert HCV test Results and interpretation.

*Do not perform more than one retest of the sample

C Instrument Description Information

1. Instrument Name:

The Xpert HCV test is performed on the Gene Xpert Xpress System (Hub Configuration) with GeneXpert Xpress Software Version 6.4a or higher.

The GeneXpert Xpress System (Hub configuration) consists of a GeneXpert IV instrument with the capability of running 2 or 4 modules and a single-unit accessory called the GeneXpert Hub that integrates the computer, touchscreen monitor and barcode scanner. The

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GeneXpert Xpress System contains preloaded GeneXpert Xpress software for running the tests and viewing the results (executes the sample preparation, nucleic acid amplification, and real-time fluorescent signal detection for the test). Simple instructions (GeneXpert Xpress Getting Started Guide) are provided for attaching the Hub and the GeneXpert System. The system is capable of bi-directional connectivity (upload and download) with the Laboratory Information System (LIS).

The GeneXpert module is the basic functional operation unit common to all GeneXpert Systems including the GeneXpert Xpress System. Each GeneXpert module is identical and operates independently. Each module consists of a syringe pump drive for dispensing fluids, an ultrasonic horn for lysing cells or spores, a valve drive to rotate the cartridge valve body for sample movement across the different cartridge chambers, and a proprietary microprocessor controlled I-CORE (Intelligent Cooling/Heating Optical Reaction) thermocycler for performing real-time PCR amplification and fluorescence signal detection.

1. Specimen Identification:
  To perform a test, the user touches the 'NEW TEST' icon on the Home Screen. Either patient information must be entered if configured by an administrator or the Sample ID screen appears.
If the Patient Information screen appears, the operator manually enters the patient ID or scans the patient ID barcode for the patient's specimen.
If the Sample ID screen appears, the operator scans the sample ID barcode or manually enter the Sample ID for the patient specimen.

The user is then instructed to scan the cartridge barcode and confirm that the appropriate cartridge for the Xpert Xpress HCV test has been selected. The test cartridge is prepared and loaded into an available instrument module that has a flashing green light which initiates the test.

1. Specimen Sampling and Handling:
  The Xpert HCV test is designed for use with human K2- EDTA fingerstick whole blood. The BD Microtainer for capillary whole blood collection was validated for use with the Xpert HCV test. The fingerstick whole blood collection should follow the package insert provided in the BD Microtainer kit. In addition, the fingerstick whole blood collection instructions are also provided in the Xpert HCV package insert, and a fingerstick whole blood collection instruction video can be accessed by scanning the QR code provided in the Xpert HCV package insert and Quick Reference Instructions (QRI). This video must be viewed before collecting the first patient sample. The video should be viewed again if sample collection issues are experienced.
1. Calibration:
  Cepheid performs all necessary optical and thermal calibrations of the GeneXpert Xpress instrument at the time of manufacture, prior to customer installation; therefore, calibration of the instrument is not required during initial system startup. Cepheid recommends that the system be checked for proper calibration on an annual basis from the point of initial use. A

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GeneXpert operator or Cepheid Field Service Engineer with Administrator user permissions can perform calibration checks during annual maintenance.

5. Quality Control:

Internal controls:

Each test includes a Sample Volume Adequacy (SVA) control, sample processing control (SPC), an internal control high (IC-H), and a Probe Check Control (PCC).

· Sample Volume Adequacy (SVA) Ensures the sample was correctly added to the cartridge. The SVA verifies that the correct volume of sample has been added in the sample chamber. The SVA passes if it meets the validated acceptance criteria. If the SVA does not pass, NO RESULT-REPEAT TESTING will be displayed. The SVA error can be caused by cartridge-related error associated with insufficient sample volume. The system will prevent the test from being processed.
· Sample Processing Control (SPC) and Internal Control High (IC-H) The SPC and IC-H are two RNA controls unrelated to HCV that are included in each cartridge and go through the whole test process. They ensure that the sample was correctly processed and detect specimen-associated inhibition of the RT-PCR. The SPC and IC-H should PASS in a negative sample and be N/A in a positive sample. The SPC and IC-H pass if they meet the validated acceptance criteria. For SPC, the valid Ct range is 31.0 to 37.0. For IC-H, the valid Ct range is 20.0 to 26.0.
· Probe Check Control (PCC) Before the start of the PCR, the GeneXpert Xpress System measures the fluorescence signal from the probes to monitor bead rehydration, reaction tube filling, probe integrity and dye stability. The PCC passes if it meets the validated acceptance criteria.

External Controls:

Additionally, external positive and negative quality controls are available but not provided with the kit:

NAT troll Hepatitis C Virus Positive Control (ZeptoMetrix Corporation, NATHCV-● 6C-IVD).
NAT troll Hepatitis C Virus Negative Control (ZeptoMetrix Corporation, NATHCVNEG-6C-IVD).

V Standards/Guidance Documents Referenced:

Standards

CLSI EP05-A3. Evaluation of Precision of Quantitative Measurement Procedures; Approved Guideline-Third Edition. CLSI document EP05-A3. Wayne, PA: Clinical and Laboratory Standards Institute; 2014.

CLSI EP07-3rd Ed. Interference Testing in Clinical Chemistry, 3rd Edition. CLSI guideline EP07. Wayne, PA. Clinical and Laboratory Standards Institute; 2018.

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CLSI EP09c- 3rd Ed. Measurement Procedure Comparison and Bias Estimation Using Patient Samples, 3rd Ed. CLSI guideline EP09c. Wayne, PA. Clinical and Laboratory Standards Institute: 2018.

CLSI EP12-A2. User Protocol for Evaluation of Qualitative Test Performance, Approved Guidance - Second edition. CLSI document EP12-A2. Wayne, PA: Clinical and Laboratory Standards Institute; 2008.

CLAI EP 17-A2. Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures, Approved Guideline - 2nd Edition. CLSI document EP17-A2. Clinical and Laboratory Standards Institute; 2012.

CLSI EP25-A. Evaluation of Stability of In Vitro Medical Laboratory Test Reagents; Approved Guideline. CLSI document EP25-A. Wayne, PA: Clinical and Laboratory Standards Institute; 2009.

CLSI MM03 3rd Ed. Molecular Diagnostic Methods for Infectious Diseases, 3rd Edition. CLSI document MM03. Clinical and Laboratory Standards Institute; 2015.

CLSI MM13 2nd Ed. Collection, Transport, Preparation, and Storage of Specimens for Molecular Methods, 2nd Edition. CLSI guideline MM13. Clinical and Laboratory Standards Institute; 2020.

ISO 14971:2019-12. Medical Devices - Application of Risk Management to Medical Devices. Third Edition.

ISO 13485:2016. Medical devices - Quality management systems - Requirements for regulatory purposes.

ANSI AAMI IEC 62304:2006/A1:2016: Medical device software - Software life cycle processes.

IEC 60601-1-2. Edition 4.1 2020-09. Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance - Collateral Standard: Electromagnetic disturbances - Requirements and tests.

IEC 61326-1, Edition 3.0 2020-10. Electrical equipment for measurement, control and laboratory use - EMC requirements - Part 1: General requirements.

IEC 61326-2-6, Edition 3.0 2020-10. Electrical equipment for measurement, control and laboratory use - EMC requirements - Part 2-6: Particular requirements - In vitro diagnostic (IVD) medical equipment.

Guidance documents

Acceptance Review for De Novo Classification Requests: Guidance for Industry and Food and Drug Administration Staff, issued October 5, 2021.

De Novo Classification Process (Evaluation of Automatic Class III Designation): Guidance for Industry and Food and Drug Administration Staff, issued October 5, 2021.

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Consideration of Uncertainty in Making Benefit-Risk Determinations in Medical Device Premarket Approvals, De Novo Classifications, and Humanitarian Device Exemptions: Guidance for Industry and Food and Drug Administration Staff, issued August 30, 2019.

Factors to Consider When Making Benefit-Risk Determinations in Medical Device Premarket Approval and De Novo Classifications: Guidance for Industry and Food and Drug Administration Staff, issued August 30, 2019.

eCopy Program for Medical Device Submissions: Guidance for Industry and Food and Drug Administration Staff, issued April 27, 2020.

Appropriate Use of Voluntary Consensus Standards in Premarket Submissions for Medical Devices: Guidance for Industry and Food and Drug Administration Staff, issued September 14, 2018.

Off-The-Shelf Software Use in Medical Devices: Guidance for Industry and Food and Drug Administration Staff, issued August 11, 2023.

Content of Premarket Submissions for Device Software Functions: Guidance for Industry and Food and Drug Administration Staff, issued June 14, 2023.

General Principles of Software Validation: Guidance for Industry and FDA Staff, issued January 11,2002.

Cybersecurity in Medical Devices: Quality System Considerations and Content of Premarket Submissions: Guidance for Industry and Food and Drug Administration Staff, issued on September 27, 2023.

Cybersecurity for Networked Medical Devices Containing Off-the-Shelf (OTS) Software: Guidance for Industry, issued January 14, 2005.

Guidance on Informed Consent for In Vitro Diagnostic Device Studies Using Leftover Human Specimens that are Not Individually Identifiable: Guidance for Sponsors, Institutional Review Boards, and Food and Drug Administration Staff, issued April 25, 2006.

Electromagnetic Compatibility (EMC) of Medical Devices: Guidance for Industry and Food and Drug Administration Staff, issued June 6, 2022.

Performance Characteristics: VI

A Analytical Performance:

1. Precision/Reproducibility:

Precision Study: The lot-to-lot variability of the Xpert HCV test was established through a single site, blinded, and randomized precision study using three lots of the Xpert HCV cartridges. The study tested three clinical HCV strains from Genotype (GT) 1a, GT2b, and

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GT3a and external controls (one positive and one negative). Three analyte levels were tested for each genotype: negative, ~1.5x LoD, and ~3.0x LoD. The study was conducted with two trained operators, during 5 independent days of testing, with two runs per day (1 run per operator per day), and two replicates per sample per run, using one GeneXpert Xpress System (four module system) with the Hub configuration (GeneXpert Xpress software version 6.4a or higher). The total number of replicates per sample tested was 60. Table 2 summarizes the percent correct for each panel level and 95% CI using the Wilson score method.

Panel Member	% Agreementa	95% CI
Negative	100% (60/60)	94.0% - 100%
GT1a 1.5 x LoD	100% (60/60)	94.0% - 100%
GT1a 3.0 x LoD	100% (60/60)	94.0% - 100%
GT2b 1.5 x LoD	95.0% (57/60)	86.3% - 98.3%
GT2b 3.0 x LoD	100% (60/60)	94.0% - 100%
GT3a 1.5 x LoD	100% (59/59)b	93.9% - 100%
GT3a 3.0 x LoD	100% (60/60)	94.0% - 100%

Table 2. Summary of Precision Percent Agreement Results for the Xpert HCV test.

4Number of Replicates with Expected Results / Number of Valid Replicates. All replicates provided valid results.

bone (1) samples yielded non-determinate results on initial and retesting.

The precision of the Xpert HCV test was also evaluated in terms of the fluorescence signal expressed in Ct values for each target detected. The mean, standard deviation (SD) and coefficient of variation (CV) are provided for each covariate: within-run (repeatability), between-run, between-days, between-lots, and total precision for each panel member are presented in Table 3.

Table 3. Summary of Ct Variance Components Observed in the Precision Study.

Target and Level	Analyte ofCt Values	Na	Mean Ct	Repeatability(Within run)		Between Runs		Between Days		Between Lots		Total Variance(Within-Laboratory)
				SD	CV (%)	SD	CV (%)	SD	CV (%)	SD	CV (%)	SD	CV (%)
Negative	SPC	60	35.09	0.43	1.23	0.00	0.00	0.22	0.64	0.35	0.99	0.60	1.70
GT1a 1.5 x LoD	HCV	60	38.43	0.91	2.36	0.25	0.64	0.00	0.00	0.35	0.92	1.00	2.61
GT1a 3.0 x LoD	HCV	60	37.89	0.71	1.87	0.22	0.58	0.35	0.93	0.29	0.76	0.87	2.30
GT2b 1.5 x LoD	HCV	57	39.77	1.20	3.02	0.00	0.00	0.35	0.88	0.52	1.30	1.35	3.40
GT2b) 3.0 x LoD	HCV	60	38.44	0.70	1.82	0.47	1.23	0.00	0.00	0.16	0.41	0.86	2.23
GT3a 1.5 x LoD	HCV	59	38.43	0.87	2.27	0.00	0.00	0.14	0.36	0.43	1.13	0.99	2.56
GT3a 3.0 x LoD	HCV	60	37.27	0.53	1.41	0.00	0.00	0.22	0.59	0.00	0.00	0.57	1.53

ªN is the total number of non-zero Ct values bCV (%) = SD/Mean Ct * 100

Multi-Site Reproducibility Study: The reproducibility of the Xpert HCV test was established through a multicenter (3 CLIA-Waived sites), blinded and randomized study, using a single reagent lot of the Xpert HCV cartridges. The study tested three clinical HCV strains from

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Genotype (GT) 1a, GT2b, and GT3a and external controls (one positive and one negative). Three analyte levels were tested for each genotype: negative, ~ 1.5x LoD, and ~3.0x LoD. The study was conducted with three untrained operators per site, during 5 independent days of testing, with one run per day (1 run per operator per day), and two replicates per sample per run, using one GeneXpert Xpress System (four module system) with the Hub configuration (GeneXpert Xpress software version 6.4a or higher). The total number of replicates per sample tested was 90. Table 4 summarizes the percent correct for each panel level, and 95% CI using the Wilson score method.

Target andLevel	Site 1				Site 2				Site 3				Agreement byTarget
	Op1	Op2	Op3	SiteTotal	Op1	Op2	Op3	SiteTotal	Op1	Op2	Op3	SiteTotal	(%; 95%CI)
Negative	100%	100%	90%	96.7%	100%	100%	100%	100%	100%	100%	100%	100%	98.9%(94.0% - 99.8%)
	10/10	10/10	9/10	29/30	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	89/90
GT1a 1.5 x LoD	100%	90%	100%	96.7%	100%	100%	100%	100%	100%	100%	100%	100%	98.9%(94.0% - 99.8%)
	10/10	9/10	10/10	29/30	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	89/90
GT1a 3.0 x LoD	100%	100%	90%	96.7%	100%	100%	100%	100%	100%	100%	100%	100%	98.9%(94.0% - 99.8%)
	10/10	10/10	9/10	29/30	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	89/90
GT2b 1.5 x LoD	100%	90%	100%	96.7%	100%	90%	100%	96.7%	100%	90%	100%	96.7%	96.7%(90.7% - 98.9%)
	10/10	9/10	10/10	29/30	10/10	9/10	10/10	29/30	10/10	9/10	10/10	29/30	87/90
GT2b 3.0 x LoD	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%(95.9% - 100%)
	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	90/90
GT3a 1.5 x LoD	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%(95.9% - 100%)
	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	90/90
GT3a 3.0 x LoD	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%(95.9% - 100%)
	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	10/10	10/10	10/10	30/30	90/90

Table 4. Summary of Reproducibility Percent Agreement Results for the Xpert HCV test

The reproducibility of the Xpert HCV test was also evaluated in terms of the fluorescence signal expressed in Ct values for each target detected. The mean, standard deviation (SD), and coefficient of variation (CV) are provided for each covariate: within-run (repeatability), between-operators, between-days, between-sites, and total reproducibility for each panel member are presented in Table 5.

Table 5. Summary of Ct Variance Components Observed in the Reproducibility Study.

Target and Level	Analyte of Ct Values	Na	Mean Ct	Repeatability (Within Run)		Between Days		Between Operators		Between Sites		Reproducibility
				SD	CV (%)b	SD	CV (%)	SD	CV (%)	SD	CV (%)	SD	CV (%)
Negative	SPC	90	35.05	0.44	1.25	0.00	0.00	0.27	0.76	0.00	0.00	0.51	1.46
GT1a 1.5x LoD	HCV	89	38.42	0.90	2.33	0.00	0.00	0.36	0.95	0.00	0.00	0.97	2.52
GT1a 3.0x LoD	HCV	89	37.63	0.68	1.82	0.00	0.00	0.28	0.74	0.00	0.00	0.74	1.96
GT2b 1.5x LoD	HCV	87	39.53	0.91	2.31	0.45	1.14	0.00	0.00	0.43	1.08	1.10	2.79
GT2b 3.0x LoD	HCV	90	38.43	0.73	1.90	0.08	0.20	0.06	0.17	0.22	0.57	0.77	2.00
GT3a 1.5x LoD	HCV	90	38.18	0.82	2.15	0.20	0.52	0.25	0.67	0.00	0.00	0.88	2.31

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GT3a 3.0x LoD	HCV	90	37.14	0.74	1.99	0.00	0.00	0.22	0.58	0.00	0.00	0.77	2.07
---------------	-----	----	-------	------	------	------	------	------	------	------	------	------	------

aN is the total number of non-zero Ct values

The Xpert HCV test demonstrated acceptable reproducibility across sites, operators, and panel members when testing was performed in a CLIA-waived environment.

1. Linearity:
  Not Applicable.1
1. Analytical Specificity/Interference:
  Analytical Specificity: The analytical specificity of the Xpert HCV test was evaluated by testing a panel of 27 organisms that can be encountered in samples drawn for HCV testing. These organisms were tested at a concentration of 100,000 CFU/mL, copies/mL, or TCID50/mL as applicable. Each organism in the panel was tested in the presence (3-time Limit of Detection (LoD)) and absence of HCV RNA in replicates of 6. Positive and Negative HCV controls tested in replicates of 6 were also included in the study. The study was completed using a single kit lot.

None of the organisms tested in this study (Table 6) showed cross reactivity with the HCV detection using the Xpert HCV test in HCV-positive and HCV-negative samples.

Virus	Bacteria	Fungus
Human Immunodeficiency virus 1 (HIV-1)	Staphylococcus aureus	Candida albicans
Human Immunodeficiency virus 2 (HIV-2)	Streptococcus epidermidis
Human T-cell Lymphotropic virus Type 1(HTLV-I)

Human T-cell Lymphotropic virus Type 2(HTLV-II)

Dengue Virus
West Nile Virus
Zika Virus
Banzi Virus
Ilheus Virus
Yellow Fever Virus
Cytomegalovirus
Epstein-Barr Virus (EBV)
Hepatitis A Virus (HAV)
Hepatitis B virus (HBV)
Herpes simplex Virus 1 (HSV-1)
Herpes simplex Virus 2 (HSV-2)
Herpes simplex Virus 6 (HHV-6)
Herpes simplex Virus 8 (HHV-8)
Varicella Zoster Virus (VZV)
BK Human Polyoma Virus

Table 6. List of organisms tested in the analytical specificity study.

1 Linearity study is not applicable to Xpert HCV test because the device is qualitative. Special control (b) (5) (i) applies to quantitative devices only.

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Human papilloma Virus 16 (HPV-16)
Human papilloma Virus 18 (HPV-18)
St. Louis Encephalitis Virus
Vaccinia Virus

Interference Study: The Xpert HCV test was evaluated for interference in the presence of elevated levels of endogenous and exogenous substances commonly found in fingerstick whole blood specimens from individuals in the intended use population. Endogenous substances, exogenous substances, and autoimmune disease specimens were tested in the presence (300 IU/mL) and absence of HCV RNA. Each endogenous and exogenous substance was tested in replicates of six, and the autoimmune disease specimens in replicates of three. Two controls without any endogenous substance consisting of HCV negative EDTA venous whole blood and HCV negative EDTA venous whole blood spiked with HCV to 300 IU/ml was included and tested in replicates of six. This study was conducted using one kit lot.

None of the substances and autoimmune conditions tested in this study interfere with the Xpert HCV test at the concentrations listed in the tables below.

Endogenous Substance	Concentration forTesting
Albumin	9 g/dL
Bilirubin	20 mg/dL
Hemoglobin	500 mg/dL
Human DNA	0.4 mg/dL
Triglycerides	3,000 mg/dL

Table 7. Endogenous interferents evaluated with the Xpert HCV test.

	Table 8. Exogenous interferent pools evaluated with the Xpert HCV test.
--	-------------------------------------------------------------------------	--

Drug Pool	Generic Name	Concentration forTesting (3xCmax)	Tested as*:
Pool 1	Zidovudine	6.00 µg/ml	Drug
	Abacavir sulfate	11.67 µg/ml	Drug
	Saquinavir	0.59 µg/ml	Drug
	Ritonavir	44.40 µg/ml	Drug
	Interferon 2b	819.00 IU/ml	Drug
Pool 1	Ombitasvir	0.20 µg/ml	API
	Paritaprevir	0.79 µg/ml	API
	Dasabuvir	2.00 µg/ml	API
	Fosamprenavir	17.16 µg/ml	Drug
Pool 2	Peginterferon alfa-2a	0.08 µg/ml	Drug
	Peginterferon alfa-2b	0.00032 µg/ml	Drug
	Ribavirin	10.70 µg/ml	Drug
	Ledipsavir	0.97 µg/ml	API
	Sofosbuvir	1.85 µg/ml	API
	Daclatasvir	4.60 µg/ml	API
	Simeprevir	5.81 µg/ml	API

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Pool 3	Tenofovir disoproxilfumarate	1.17 µg/ml	Drug
	Lamivudine	6.00 µg/ml	Drug
	Indinavir sulfate	35.57 µg/ml	Drug
	Ganciclovir	31.20 µg/ml	Drug
	Acyclovir	68.70 µg/ml	Drug
	Valganciclovir HCl	34.44 µg/ml	Drug
Pool 4	Stavudine	2.05 µg/ml	Drug
	Efavirenz	15.72 µg/ml	Drug
	Lopinavir	40.50 µg/ml	Drug
	Enfuvirtide	18.27 µg/ml	Drug
	Ciprofloxacin	4.77 µg/ml	API
	Clarithromycin	5.10 µg/ml	Drug
Pool 5	Maraviroc	1.00 µg/ml	Drug
	Nevirapine	7.20 µg/ml	Drug
	Nelfinavir	14100.00 µg/ml	API
	Azithromycin	2.10 µg/ml	Drug
	Valacyclovir	24.06 µg/ml	Drug

*API: Active Pharmaceutical Ingredient

Table 9. Autoimmune disease samples evaluated with the Xpert HCV test.

Condition	Number of Specimens
SLE / ANA positive	7
SLE /ANA negative	2
SLE / ANA unknown	3
RA / RF positive	8

SLE: Systemic Lupus Erythematosus, ANA: Anti-Nuclear Antibodies RA: Rheumatoid Arthritis, RF: Rheumatoid Factor

4. Assay Reportable Range:

Not applicable

5. Traceability, Stability, Expected Values (Controls, Calibrators, or Methods):

Fingerstick Whole Blood specimen stability: The stability of hepatitis C virus genotype 1a in fingerstick whole blood (FS) was evaluated after storage at 2°C and 30°C for up to five hours. Freshly drawn FS collected from 6 individuals were included in the study. Individuals providing the FS were confirmed HCV-negative using cobas HCV assay. Each individual provided three 250 – 500 µl samples of FS in K2 EDTA microtainer tubes. FS samples from five individual were spiked at a final concentration of 3x LoD with contrived HCV-positive venous whole blood (VWB) samples. FS samples from one individual were spiked with HCV-negative VWB to generate HCV-negative samples.

Samples were stored at 2℃ or 30℃ and tested in singlicate at baseline (T=0 hours), 2 hours, 4 hours, and 5 hours. For each sample at each timepoint, test results were reported as HCV DETECTED and HCV NOT DETECTED.

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The study results support the stability of FS stored for up to 4 hours at 2ºC and 30ºC.

External Controls: the external positive and negative controls are available but not provided with the Xpert HCV test. The external controls for use with the Xpert HCV test include:

NAT troll Hepatitis C Virus Positive Control (ZeptoMetrix Corporation, NATHCV-● 6C-IVD).
NAT troll Hepatitis C Virus Negative Control (ZeptoMetrix Corporation, ● NATHCVNEG-6C-IVD).

The instruction for use recommends that external controls be tested at the frequency noted below:

Each time a new lot of Xpert HCV kits is received. ●
Each time a new shipment of Xpert HCV kits is received even if it is the same lot ● previously received.
. Each time a new operator is performing the test (i.e., operator who has not performed the test recently).
When problems (storage, operator, instrument, or other) are suspected or identified. ●
If otherwise required by your institution's standard Quality Control (OC) procedures.
1. Detection Limit:

The LoD of the Xpert HCV test was determined by testing dilutions of hepatitis C virus RNA for genotypes 1a, 1b, 2b, 3a, 4, 5 and 6 in HCV negative human K2-EDTA fingerstick whole blood. Each panel was tested following the package insert. Probit analysis was used to determine the LoD. Table 10 below summarizes the LoD for each genotype in fingerstick whole blood.

Table 10. Summary of Xpert HCV LoD for genotypes 1a, 1b, 2b, 3a, 4, 5, and 6 in Fingerstick Whole Blood.

Genotype	Fingerstick whole bloodLoD (IU/mL)	95% Confidence Interval(IU/mL)
1a	35.0	(22.3 - 54.9)
1b	41.5	(29.8 - 57.9)
2b	89.2	(47.7 - 166.8)
3a	58.2	(39.0 - 86.7)
4	32.2	(21.1 - 49.1)
5	136.4	(83.2 - 223.4)
6	83.8	(57.2 - 122.8)

7. Assay Cut-Off:

Not Applicable

1. Accuracy (Instrument):
  Not Applicable

9. Carry-Over:

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Not Applicable

B Comparison Studies:

1. Method Comparison:
  Not Applicable
1. Matrix Comparison:
  Not applicable

C Clinical Studies:

1. Clinical Sensitivity:
  Not Applicable
1. Clinical Specificity:
  Not Applicable

3. Other Clinical Supportive Data (When 1. and 2. Are Not Applicable):

Prospective all-comers blinded clinical study was conducted to evaluate the performance of the Xpert HCV test. The study was conducted at 15 CLIA waived sites from geographically diverse locations in the US with 32 untrained operators. Participants included individuals ≥ 22 years of age who were at risk and/or with signs and symptoms for HCV infection. A total of 1,012 fingerstick whole blood (FS) specimens were obtained from eligible participants for testing with the Xpert HCV test. In addition, serum specimens were tested on an FDA approved HCV RNA test and an FDA approved HCV antibody test to establish the patient infected status (PIS). Patient management continued at the site per the standard practice, independent of investigational test results.

Table 11 below summarizes the total number of participants by risk factor. Available demographic data collected from study participants are presented Table 12.

Risk Factora	n/N (%)
Intravenous drug use	422 / 1012 (41.7%)
Persons who are HIV-positive	148 / 1012 (14.6%)
Blood transfusion or organ transplant received prior to 1992	12 / 1012 (1.2%)
Blood clotting factor for hemophilia received prior to 1987	1 / 1012 (0.1%)
Born between 1945 and 1965	406 / 1012 (40.1%)
Born to an HCV-infected mother	5 / 1012 (0.5%)

Table 11. Categorization of Risk Factors for the Eligible Participants

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Chronic hemodialysis patients	3 / 1012 (0.3%)
Persons who engage in high-risk sexual behavior	111 / 1012 (11.0%)
Persons with known exposure to HCV, such as Healthcare workers after needle sticks involving HCV-positive blood and Recipients of blood or organs from a donor who tested HCV-positive	53 / 1012 (5.2%)

4 Participants may have reported multiple risk factors.

Demographic Characteristics	Overall(N=1012)
Age	>=22 years old <=60>60	646 (63.8%)366 (36.2%)
Gender	MaleFemale	544 (53.8%)468 (46.2%)
Racea	Black/African American	369 (36.5%)
	White	521 (51.5%)
	Asian	10 (1.0%)
	Otherb	93 (9.2%)
	Unknown/Prefer not to answerMissing	18 (1.8%)1 (0.1%)
Ethnicity	Hispanic Latino	130 (12.8%)
	Not Hispanic Latino	862 (85.2%)
	Unknown/Prefer not to answerNot Available /Missing	16 (1.6%)4 (0.4%)
History of HCV infection	Yes	293 (29.0%)
	No	717 (70.8%)
	Missing	2 (0.2%)
Recent HCV antibody test	Yes	544 (53.8%)
	NA	158 (15.6%)
	Never had an HCV antibody testMissing	308 (30.4%)2 (0.2%)
Results of recent HCV antibodytest	Reactive	164 (16.2%)
	Not Reactive	376 (37.2%)
	Invalid	3 (0.3%)
	No Resultc	469 (46.3%)
Recent HCV NAAT test	Yes	204 (20.2%)
	Not Available	196 (19.4%)
	Never had an HCV NAAT testMissing	611 (60.4%)1 (0.1%)
Result of recent HCV NAATTest	Positive	34 (3.4%)
	Negative	170 (16.8%)
	No Resultd	808 (79.8%)
	Yes	46 (4.5%)
HCV Genotype Test	NA	246 (24.3%)
	Never had a HCV genotyping testMissing	719 (71.0%)1 (0.1%)
	Genotype Result	1a1b

Table 12. Demographic Data Summary of Participants

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Demographic Characteristics	Overall(N=1012)
1c	2 (0.2%)
2b	2 (0.2%)
3a	5 (0.5%)
No Resulte	967 (95.6%)
Treatment HistoryNot currently treated	175 (17.3%)
Treatment HistoryNever been treated	836 (82.6%)
Treatment HistoryMissing	1 (0.1%)
SymptomaticYes	373 (36.9%)
SymptomaticNo	639 (63.1%)
At riskYes	934 (92.3%)
At riskNo	78 (7.7%)
Symptomatic and at riskYes	295 (29.2%)
Symptomatic and at riskNo	717 (70.8%)
History of injection drug useYes	437 (43.2%)
History of injection drug useNo	575 (56.8%)
History of Non-HCV liverdisease Yes	68 (6.7%)
History of Non-HCV liverdisease No	943 (93.2%)
History of Non-HCV liverdisease Missing	1 (0.1%)
HIV Status Positive	154 (15.2%)
HIV Status Negative	799 (79.0%)
HIV Status Unknown (Never tested)	59 (5.8%)
HBV Status Positive	16 (1.6%)
HBV Status Negative	684 (67.6%)
HBV Status Unknown (Never tested)	311 (30.7%)
HBV Status Missing	1 (0.1%)

a If more than one race is reported for a participant, they are only captured in one category.

b Other race group includes "American-Indian or Alaskan Native", "More than one race", "Native Hawaiian or Pacific Islander" and "Other"

& Combined category of "Not Available", "Never had a HCV Antibody Test" and "Missing"

d A combined category of "Not Available", "Never had a HCV NAAT Test" and "Missing"

e A combined category of "Not Available", Never had a HCV Genotyping Test" and "Missing"

Of the 1,012 eligible samples, 30 samples were excluded due to the following reasons: 1) protocol deviations (n=15); 2) unresolved ND results for Xpert HCV test (n=11); and 3) nonevaluable comparator test results (n=4). A total of 982 FS samples tested were included in the Xpert HCV test performance calculations. Table 13 summarizes the Xpert HCV test results by patient infected status (PIS).

HCV Ab	HCV RNANAAT	Patient Infectionstatus	Xpert HCV	N
Reactive	Reactive	Active chronicinfection	HCVDETECTED	111
			HCV NOTDETECTED	6
	Non-reactive	Past/resolvedinfection	HCVDETECTED	1
			HCV NOTDETECTED	223

Table 13. Summary of samples by infected status (PIS)

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Reactive	Active acuteinfection	HCVDETECTED	3
		HCV NOTDETECTED	2
Non-reactive	Not infected	HCVDETECTED	1
		HCVDETECTED	635

The Xpert HCV test performance was compared to a patient infected status (PIS) algorithm based on results from an FDA approved HCV RNA test and an antibody test. Table 14 below summarize the Xpert HCV test performance. The Xpert HCV test demonstrated positive percent agreement (PPA) and negative percent agreement (NPA) of 93.44% and 99.77%, respectively when compared to the PIS.

		Patient Infection Status
		HCV Positivea	HCV Negativeb	Total
XpertHCVtest	HCV detected	114	2	116
	HCV notdetected	8	858	866
	Total	122	860	982
	PPA*	93.44%; 95% CI (87.59% – 96.64%)
	NPA*	99.77%; 95% CI (99.16% – 99.94%)

Table 14. Xpert HCV test result according to PIS

ª Active chronic or acute infection.

b Past/resolved infection or not infected.

Two (2) specimens (1 false positive and 1 false negative) with suspicion of specimen handling and testing errors were retested along with 110 additional serum specimens on the HCV RNA NAAT comparator test (15 positive and 95 negative). Retesting confirmed the specimen handling and testing error at the reference laboratory.

4. Non-Determinate Rate

Of the 1,012 Xpert HCV runs performed in the clinical study, 61 resulted in non-determinate ("INSTRUMENT ERROR" or "NO RESULT - REPEAT TEST") results on first attempt. Upon retest of these 61 specimens, 12 remained non-determinate. The initial nondeterminate rate was 6.0 % (61/1,012) and the overall non-determinate rate was 1.2 % (12/1,012).

5. Testing non-viral hepatitis samples

FS samples from individuals with other liver diseases (where active HCV infection was not indicated as the underlying cause) were collected during the clinical study. Samples were tested with an FDA-approved anti-HCV test and an FDA-approved HCV molecular test to confirm the samples were HCV negative. Seventy-eight (78) samples from individuals with non-viral hepatitis were included in the study.

The table below shows subject demographics and liver disease status for the 78 evaluable subjects.

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Table 15: Non-viral Hepatitis Disease Group Clinical Performance by Disease

Non-viralLiver Diseasea	N of Xpert Testby DiseaseOccurrence	N of XpertTestComparedto PISb	TP	TN	PPA with 95% CI (%)	NPA with 95% CI(%)
MetabolicDysfunction-AssociatedSteatotic LiverDisease(MASLD)	28	24	1	23	100.0%(95% CI: 20.7 - 100.0)	100.0%(95% CI: 85.7- 100.0)
NASH	2	1	0	1	N/A	100.0%(95% CI: 20.7 - 100.0)
Primary biliarycirrhosis	15	13	2	11	100.0%(95% CI: 34.2 - 100.0)	100.0%(95% CI: 74.1 - 100.0)
Chronic HBV	3	2	0	2	N/A	100.0%(95% CI: 34.2 - 100.0)
Alcoholic liverdisease	11	10	0	10	N/A	100.0%(95% CI: 72.2 - 100.0)
Autoimmunehepatitis	3	3	0	3	N/A	100.0%(95% CI: 43.9 - 100.0)
Other	16	15	1	14	100.0%(95% CI: 20.7 - 100.0)	100.0%(95% CI: 78.5 - 100.0)
Total	78	68	4	64	100.0%(95% CI: 51.0 - 100.0)	100.0%(95% CI: 94.3 - 100.0)

ª Patients may have multiple non-viral liver diseases

b With both valid Xpert test result and valid PIS results

D Clinical Cut-Off:

Not Applicable

Expected Values/Reference Range: E

Not Applicable

Other Supportive Performance Characteristics Data: F

Not Applicable

Proposed Labeling: VII

The labeling supports the decision to grant the De Novo request for this device.

Identified Risks and Mitigations: VIII

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Identified Risks to Health	Mitigation Measures
Risks of false test results	Certain labeling information, includinglimitations, device descriptions, explanationof procedures, and results interpretationinformation.
	Certain design verification and validationinformation, certain analytical studies andclinical studies, risk analysis strategies, lotrelease criteria, flex studies, and stabilitystudies.
Failure to correctly interpret the results	Certain labeling information, includinglimitations, device descriptions, explanationof procedures, and results interpretationinformation.
	Certain design verification and validationinformation, including critical reagentinformation, risk analysis strategies, lotrelease criteria, flex studies, and stabilitystudies and protocols.
Failure to correctly operate the device	Certain labeling information, includinglimitations, device descriptions, andexplanation of procedures.
	Certain design verification and validationinformation including critical reagentinformation, risk analysis strategies, lotrelease criteria, flex studies, and stabilitystudies.

IX Benefit/Risk Assessment:

A Summary of the Assessment of Benefit:

The benefit of the assay is the ability to detect HCV RNA to aid a clinician in the diagnosis of hepatitis C virus (HCV) infection in individuals with signs and symptoms or risk factors for HCV infection without needing an HCV antibody result. Diagnosis of HCV infection with the aid of this device can occur within one encounter with the healthcare system. Individuals diagnosed with HCV infection with the aid of the candidate device can be treated with indicated antiviral treatment. Treatment of HCV infection helps prevent known complications of undiagnosed and untreated HCV infection, including by symptom alleviation, decreases in allcause mortality, liver disease-related complications and death, hepatocellular carcinoma rates, and need for liver transplantation. Diagnosis of HCV infection can improve patient knowledge of the condition, inform prognosis, and guide the need for additional imaging or laboratory testing. Diagnosis of HCV infection also leads clinicians to evaluate and subsequently treat patients for human immunodeficiency virus (HIV) and hepatitis B virus (HBV), if indicated, as these viruses share common modes of transmission with HCV, and co-infection is widely documented.

{20}------------------------------------------------

Diagnosis could also decrease community transmission among other individuals at risk for HCV infection.

B Summary of the Assessment of Risk:

The risks associated with the device, when used as intended, are those related to the risk of false test results (false positive and false negative), failure to correctly interpret the test results, and failure to correctly operate the instrument.

Risks of a false positive test include unnecessary imaging, laboratory testing, and treatment. repeating hepatitis C testing and additional imaging and laboratory evaluations. False positive test results may have psychosocial implications for those tested.

Risks of false negative test results include missed diagnosis of HCV infection. Risks of a false negative test include the failure to treat HCV infection. Failure to diagnose and treat HCV infection will lead to increased all-cause mortality and increased likelihood of liver diseaserelated complications, including cirrhosis, hepatocellular carcinoma, and the need for liver transplantation. A failure to diagnose HCV infection could also lead to increased community transmission and disease burden in individuals at risk for infection. A false negative result may deny a clinician the opportunity to evaluate and treat a patient who is co-infected with HIV or HBV, as these viruses share common modes of transmission with HCV, and patients are often co-infected. Additional risks of false negative test results are unnecessary additional diagnostic procedures in pursuit of a different cause for the patient's hepatitis, which bear known risks such as bleeding and infection for liver biopsies and pharmacological treatment for other etiologies, which have known adverse effects such as hypersensitivity reactions.

Failure to correctly operate the device could lead to invalid results requiring retesting and leading to delayed test results. The risk of a delayed result is minimal, given the short time to results with the device. Failure to correctly interpret results carries the same risks as false results.

C Patient Perspectives:

This submission did not include specific information on patient perspectives for this device.

D Summary of the Assessment of Benefit-Risk:

The risks associated with the device (risk of false test results, failure to correctly interpret the results, and failure to correctly operate the device) are mitigated by labeling information, which will assist the operator in correctly performing the test and will assist healthcare providers in understanding the intended use of the test and evaluating the predictive value of a result based on the analytical and clinical performance of the test. In addition, the risks of false test results and failure to correctly interpret the results are mitigated by certain design verification and validation activities, including analytical and clinical studies and risk analysis strategies to reduce the likelihood of such errors. Such measures help to ensure that errors will be uncommon and will facilitate accurate assay implementation and interpretation of results. In addition, the device's performance observed in the clinical study suggests that errors will be uncommon and that the assay will provide substantial benefits to patients as an aid in the diagnosis of HCV infection in individuals at risk and/or with signs and symptoms of HCV infection with or without antibodies to HCV. There is significant morbidity and mortality associated with the natural history of disease progression of undiagnosed HCV, and barriers exist to initiation of antiviral treatment due to loss-to-follow up with current multi-step HCV testing algorithms over multiple encounters with the healthcare system. Because this test can be used at the point of care and can return a

{21}------------------------------------------------

result in approximately 60 minutes, the diagnosis of HCV can occur in one encounter with the healthcare system. Risks can be further mitigated by labeling the device as "prescription use only" and by including additional warnings noting limitations of safety information, including populations or situations for which the safety and efficacy of the device has not been evaluated. While general controls alone are insufficient to mitigate the risks associated with the device, given the special controls, the benefits outweigh the risks.

X Conclusion:

The De Novo request is granted, and the device is classified under the following, and subject to the special controls identified in the letter granting the De Novo request:

Product Code(s):	SBP
Device Type:	Simple point-of-care nucleic acid-based hepatitis C virus ribonucleic acidtest
Class:	Class II
Regulation:	21 CFR 866.3171

Regulation Number and Section

N/A