VITEK REVEAL GN AST Assay and VITEK REVEAL AST System
Device Facts
| Record ID | K230675 |
|---|---|
| Device Name | VITEK REVEAL GN AST Assay and VITEK REVEAL AST System |
| Applicant | Specific Diagnostics, LLC |
| Product Code | SAN · Microbiology |
| Decision Date | Jun 20, 2024 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 866.1650 |
| Device Class | Class 2 |
Indications for Use
The VITEK® REVEAL™ AST System is an automated system for quantitative and qualitative antimicrobial susceptibility testing (AST) of organisms direct from positive blood culture. The VITEK® REVEAL™ AST System does not provide organism identification. The VITEK® REVEAL™ AST System is an automated system that uses an array of sensors to detect volatile organic compounds emitted by growing bacteria for the in vitro diagnostic quantitative and qualitative determination of antimicrobial susceptibility. The VITEK® REVEAL™ GN AST Assay is indicated for susceptibility testing direct from positive blood culture samples signaled positive by a continuous monitoring blood culture system and confirmed to contain gram-negative bacilli by Gram stain. Organism identification is required for the AST result interpretation and reporting. This test is performed by laboratory health professionals in a clinical diagnostic setting. Results may be used as an aid to clinicians in determining appropriate antimicrobial therapy. Test results from the VITEK® REVEAL™ AST System should be interpreted in conjunction with other clinical and laboratory findings. Standard laboratory protocols for processing positive blood cultures should be followed to ensure availability of isolates for supplemental testing. Subculturing is necessary to support further testing for: bacteria and antimicrobials not on the VITEK® REVEAL™ GN AST Assay panel, inconclusive results, epidemiologic testing, recovery of organisms present in positive blood cultures samples, and susceptibility testing of bacteria in polymicrobial samples.
Device Story
VITEK REVEAL AST System performs rapid phenotypic antimicrobial susceptibility testing (AST) on positive blood culture samples. Input: aliquot from positive blood culture (confirmed Gram-negative, monomicrobial). Process: sample diluted in Pluronic water, dispensed into 96-well antibiotic panel, sealed with sensor panel containing chemical Small Molecule Sensors (SMS). Instrument monitors color changes in SMS array caused by volatile organic compounds (VOCs) emitted by bacterial metabolism during incubation. Output: MIC values, SIR interpretations, and ESBL status (after user enters species ID). Used in clinical labs; results aid clinicians in selecting antimicrobial therapy. Benefits: rapid AST results (approx. 8 hours) compared to traditional methods, enabling faster targeted therapy.
Clinical Evidence
Clinical performance was evaluated across seven US sites using 1,115 samples (424 fresh prospective, 101 clinical stock, 590 challenge). Performance was compared to reference frozen broth microdilution (BMD) per CLSI M07. Overall essential agreement (EA) and categorical agreement (CA) were high, meeting acceptance criteria for most antimicrobial agents. Trending analyses were performed to identify systematic MIC differences. Reproducibility, bottle equivalency, sample stability (up to 16 hours), and interference studies were conducted to support performance claims.
Technological Characteristics
The system utilizes colorimetric Small Molecule Sensors (SMS) to detect VOCs emitted by bacterial metabolism. It includes a sealer, instrument, and master controller. The assay uses broth microdilution in a 96-well format. Connectivity is via a touchscreen interface/master controller. Software performs real-time growth monitoring and MIC calculation. Sterilization and material standards are not explicitly detailed beyond the use of proprietary SMS arrays.
Indications for Use
Indicated for quantitative and qualitative antimicrobial susceptibility testing (AST) of Gram-negative bacilli directly from monomicrobial positive blood culture samples. Requires prior organism identification. For use by laboratory professionals in clinical diagnostic settings. Contraindicated for polymicrobial samples.
Regulatory Classification
Identification
A cellular analysis system for multiplexed antimicrobial susceptibility testing is a multiplex qualitative and/or quantitative in vitro diagnostic device intended for the identification and determination of the antimicrobial susceptibility results of organisms detected in samples from patients with suspected microbial infections. This device is intended to aid in the determination of antimicrobial susceptibility or resistance when used in conjunction with other laboratory findings.
Special Controls
*Classification.* Class II (special controls). The special controls for this device are:(1) Design verification and validation must include: (i) Detailed device description documentation, including the device components, ancillary reagents required but not provided, a detailed explanation of the methodology, including primer/probe sequence, design, rationale for sequence selection, and details of the antimicrobial agents, as applicable. (ii) Detailed documentation from the following analytical and clinical performance studies: limit of detection, inclusivity, precision, reproducibility, interference, cross-reactivity, carryover, and cross-contamination, quality control and additional studies, as applicable to specimen type and assay intended use. (iii) Detailed documentation from an appropriate clinical study. The study, performed on a study population consistent with the intended use population, must compare the device performance to results obtained from well-accepted reference methods. (iv) Detailed documentation for device software, including software applications and hardware-based devices that incorporate software. (2) The labeling required under § 809.10(b) of this chapter must include: (i) Limitations and protocols regarding the need for correlation of results by standard laboratory procedures, as applicable. (ii) A detailed explanation of the interpretation of results and acceptance criteria. (iii) A detailed explanation of the principles of operation and procedures for assay performance and troubleshooting.
Predicate Devices
- Accelerate Pheno system, Accelerate Phenotest BC Kit (K192665)
Submission Summary (Full Text)
{0}
**FDA** U.S. FOOD & DRUG
ADMINISTRATION
# **510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION
DECISION SUMMARY
ASSAY AND INSTRUMENT**
# **I Background Information:**
# **A 510(k) Number**
K230675
# **B Applicant**
Specific Diagnostics, LLC
# **C Proprietary and Established Names**
VITEK REVEAL GN AST Assay and VITEK REVEAL AST System
# **D Regulatory Information**
| Product Code(s) | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| SAN | Class II | 21 CFR 866.1650 - A Cellular Analysis System For Multiplexed Antimicrobial Susceptibility Testing | MI - Microbiology |
| LON | Class II | 21 CFR 866.1645 - Fully automated short-term incubation cycle antimicrobial susceptibility system | MI - Microbiology |
# **II Submission/Device Overview:**
# **A Purpose for Submission:**
To obtain substantial equivalence determination for use of the VITEK REVEAL AST System and VITEK REVEAL GN AST Assay for testing positive blood culture samples to determine the minimum inhibitory concentration of specific antimicrobials with specific Gram-negative organisms.
Food and Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993-0002
www.fda.gov
{1}
# **B Measurand:**
| Antimicrobial | Reporting Range |
| --- | --- |
| Amikacin | ≤0.5 to >128 μg/mL |
| Amoxicillin/clavulanate | ≤2/1 to >64/32 μg/mL |
| Ampicillin/sulbactam | ≤2/1 to >64/32 μg/mL |
| Aztreonam | ≤0.25 to >64 μg/mL |
| Cefepime | ≤0.125 to >64 μg/mL |
| Cefotaxime | ≤0.25 to >128 μg/mL |
| Ceftazidime | ≤0.125 to >64 μg/mL |
| Ceftazidime/Avibactam | ≤0.0625/4 to >32/4 μg/mL |
| Ceftolozane/Tazobactam | ≤0.0625/4 to >32/4 μg/mL |
| Ceftriaxone | ≤0.25 to >16 μg/mL |
| Cefuroxime | ≤1 to >32 μg/mL |
| Ciprofloxacin | ≤0.0625 to >8 μg/mL |
| Ertapenem | ≤0.125 to >16 μg/mL |
| Gentamicin | ≤0.25 to >32 μg/mL |
| Imipenem | ≤0.25 to >16 μg/mL |
| Levofloxacin | ≤0.125 to >16 μg/mL |
| Meropenem | ≤0.0625 to >32 μg/mL |
| Meropenem/Vaborbactam | ≤0.0625/8 to >32/8 μg/mL |
| Piperacillin/Tazobactam | ≤2/4 to >256/4 μg/mL |
| Tetracycline | ≤1 to >64 μg/mL |
| Tobramycin | ≤0.125 to >32 μg/mL |
| Trimethoprim/Sulfamethoxazole | ≤0.5/9.5 to >64/1216 μg/mL |
| ESBL | POS/NEG |
# **C Type of Test:**
Quantitative and qualitative antimicrobial susceptibility test (AST) system that utilizes sensors to detect metabolic byproducts of microbial growth from positive blood culture samples to determine the minimum inhibitory concentration (MIC) of specific antimicrobial-organism combinations.
# **III Intended Use/Indications for Use:**
# **A Intended Use(s):**
See Indications for Use.
# **B Indication(s) for Use:**
The VITEK REVEAL AST System is an automated system for quantitative and qualitative antimicrobial susceptibility testing (AST) of organisms direct from positive blood culture. The VITEK REVEAL AST System does not provide organism identification.
The VITEK REVEAL AST System is an automated system that uses an array of sensors to detect volatile organic compounds emitted by growing bacteria for the *in vitro* quantitative and qualitative determination of antimicrobial susceptibility. The VITEK REVEAL GN AST Assay is indicated for susceptibility testing direct from positive blood culture samples signaled as positive by a continuous monitoring blood culture system and confirmed to contain gram-
K230675 - Page 2 of 47
{2}
negative bacilli by Gram stain. Organism identification is required for AST result interpretation and reporting.
This test is performed by laboratory health professionals in a clinical diagnostic setting. Results may be used as an aid to clinicians in determining appropriate antimicrobial therapy. Test results from the VITEK REVEAL AST System should be interpreted in conjunction with other clinical and laboratory findings. Standard laboratory protocols for processing positive blood cultures should be followed to ensure availability of isolates for supplemental testing. Sub-culturing is necessary to support further testing for: bacteria and antimicrobials not on the VITEK REVEAL GN AST Assay panel, inconclusive results, epidemiologic testing, recovery of organisms present in positive blood cultures samples, and susceptibility testing of bacteria in polymicrobial samples.
The VITEK REVEAL GN AST Assay tests the following antimicrobial agents with the specific target organisms identified below:
Amikacin: *Acinetobacter baumannii-calcoaceticus* complex, *Citrobacter freundii* (including *Citrobacter freundii* complex), *Enterobacter cloacae* complex, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group, *Proteus mirabilis*, *Pseudomonas aeruginosa*, *Serratia marcescens*
Amoxicillin/clavulanate: *Escherichia coli*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group, *Proteus mirabilis*
Ampicillin/sulbactam: *Escherichia coli*, *Klebsiella oxytoca*, *Proteus mirabilis*
Aztreonam: *Citrobacter freundii* (including *C. freundii* complex), *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Pseudomonas aeruginosa*
Cefepime: *Citrobacter koseri* (syn. *C. diversus*), *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella* species (including *K. pneumoniae* group and *K. aerogenes*), *Klebsiella oxytoca*, *Pseudomonas aeruginosa*
Cefotaxime: *Acinetobacter baumannii-calcoaceticus* complex, *Enterobacter cloacae* complex, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group
Ceftazidime: *Acinetobacter baumannii-calcoaceticus* complex, *Citrobacter koseri*, *Enterobacter cloacae* complex, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group
Ceftazidime/avibactam: *Citrobacter freundii* complex, *Citrobacter koseri*, *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*, *Pseudomonas aeruginosa*
Ceftolozane/tazobactam: *Citrobacter koseri*, *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Proteus mirabilis*, *Proteus vulgaris*, *Pseudomonas aeruginosa*
K230675 - Page 3 of 47
{3}
Ceftriaxone: *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*
Cefuroxime: *Citrobacter koseri*, *Escherichia coli*, *Klebsiella pneumoniae* group, *Klebsiella oxytoca*, *Proteus mirabilis*
Ciprofloxacin: *Citrobacter freundii* (including *C. freundii* complex), *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*, *Proteus vulgaris*, *Pseudomonas aeruginosa*, *Serratia marcescens*
Ertapenem: *Escherichia coli*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*, *Proteus vulgaris*
Gentamicin: *Citrobacter freundii* complex, *Citrobacter koseri*, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group, *Proteus mirabilis*, *Proteus vulgaris*, *Pseudomonas aeruginosa*, *Serratia marcescens*
Imipenem: *Acinetobacter baumannii-calcoaceticus* complex, *Citrobacter koseri*, *Enterobacter cloacae* complex, *Escherichia coli*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group, *Pseudomonas aeruginosa*, *Serratia marcescens*
Levofloxacin: *Citrobacter koseri*, *Citrobacter freundii* (including *C. freundii* complex), *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*, *Proteus vulgaris*, *Pseudomonas aeruginosa*, *Serratia marcescens*
Meropenem: *Acinetobacter baumannii-calcoaceticus* complex, *Enterobacter cloacae* (including *E. cloacae* complex), *Escherichia coli*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*, *Proteus vulgaris*, *Pseudomonas aeruginosa*, *Serratia marcescens*
Meropenem/vaborbactam: *Citrobacter freundii* (including *C. freundii* complex), *Citrobacter koseri*, *Enterobacter cloacae* complex, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus mirabilis*
Piperacillin/tazobactam: *Citrobacter koseri*, *Escherichia coli*, *Klebsiella pneumoniae* (including *K. pneumoniae* group), *Proteus vulgaris*
Tetracycline: *Acinetobacter baumannii-calcoaceticus* complex, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group
Tobramycin: *Citrobacter freundii* complex, *Citrobacter koseri*, *Enterobacter cloacae* complex, *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group, *Proteus mirabilis*, *Pseudomonas aeruginosa*, *Serratia marcescens*
Trimethoprim/sulfamethoxazole: *Escherichia coli*, *Klebsiella aerogenes*, *Klebsiella pneumoniae* group
ESBL Confirmation test: *Escherichia coli*, *Klebsiella oxytoca*, *Klebsiella pneumoniae* group
K230675 - Page 4 of 47
{4}
# C Special Conditions for Use Statement(s):
Rx - For Prescription Use Only
The VITEK REVEAL GN AST Assay can only be used with the VITEK REVEAL AST System.
The VITEK REVEAL GN AST Assay should not be used for any clinical specimens other than monomicrobial positive blood cultures containing Gram-negative bacteria.
If the subculture (purity) plate indicates the sample is polymicrobial, the AST results should be voided, and susceptibility testing on each isolate type using an alternative method with standard inoculum preparation should be performed.
Positive blood cultures should be tested immediately after a positive flag, where possible. A 16-hour sample stability claim is included in case of instrument errors or if re-testing is needed.
The performance of the VITEK REVEAL AST Assay has only been evaluated using the following blood culture bottles:
BD BACTEC Plus Aerobic
BD BACTEC Plus Anaerobic
BD BACTEC Standard Aerobic
BD BACTEC Standard Anaerobic
BD BACTEC Lytic Anaerobic
BD BACTEC Peds Plus
bioMérieux BACT/ALERT FA Plus
bioMérieux BACT/ALERT FN Plus
bioMérieux BACT/ALERT PF Plus
bioMérieux BACT/ALERT SA
bioMérieux BACT/ALERT SN
The following limitations were added to the device labeling based on performance demonstrated in the current submission:
For amikacin, perform an alternative method of testing prior to reporting of results for A. baumannii-calcoaceticus complex when the MIC is 32 μg/mL due to the occurrence of minor errors, that were in essential agreement, resulting in a category agreement below 90%.
For amoxicillin/clavulanate, perform an alternative method of testing prior to reporting of results for E. coli when the MIC is 16 μg/mL due to the occurrence of minor errors, that were in essential agreement, resulting in a category agreement below 90%.
Due to the occurrence of a major errors with cefuroxime, isolates of K. pneumoniae group that provide a MIC of 16 μg/mL should be retested by an alternate method.
Due to the occurrence of a major errors with cefuroxime, isolates of K. oxytoca that provide a MIC of 32 μg/mL should be retested by an alternate method.
Due to the occurrence of a major error with cefuroxime, isolates of C. koseri that provide a MIC of > 32 μg/mL should be retested by an alternate method.
K230675 - Page 5 of 47
{5}
Due to the occurrence of a very major error with ciprofloxacin, isolates of P. mirabilis that provide a MIC of 0.25 μg/mL should be retested by an alternate method.
Due to the occurrence of a very major error with gentamicin, isolates of E. coli that provide a MIC of 4 μg/mL should be retested by an alternate method.
Due to the occurrence of very major errors with imipenem, isolates of P. aeruginosa that provide a MIC of 2 μg/mL should be retested by an alternate method.
Due to the occurrence of a very major error with levofloxacin, isolates of P. mirabilis that provide a MIC of 0.5 μg/mL should be retested by an alternate method.
Due to the occurrence of a very major error with piperacillin/tazobactam, isolates of E. coli that provide a MIC of 8 μg/mL should be retested by an alternate method.
Due to the occurrence of very major errors with tobramycin, isolates of E. coli that provide a MIC of 4 μg/mL should be retested by an alternate method.
Tobramycin with S. marcescens may produce a resistant result that can be found susceptible by the reference method. If critical to patient care, confirm these results with an alternate method.
Due to the occurrence of major error with Trimethoprim/sulfamethoxazole, isolates of E. coli that provide a MIC of 4-64 μg/mL should be retested by an alternate method.
Isolates of K. oxytoca that test as ESBL positive should be retested by an alternate method to confirm the presence of ESBL.
Interference has not been established for the following drug/organism combination for all interferents, except platelets: amoxicillin-clavulanate/Enterobacterales, aztreonam/Enterobacterales, cefepime/Enterobacterales, ceftazidime/Enterobacterales, ceftriaxone/Enterobacterales, ciprofloxacin/P. aeruginosa, levofloxacin/P. aeruginosa, ertapenem/Enterobacterales, imipenem/Enterobacterales.
During clinical studies, it was observed that mishandling of the sealed plates may cause the sample to wet the sensor. This may result in abnormal sensor responses contributing to inaccurate growth detection.
# D Special Instrument Requirements:
VITEK REVEAL GN AST Assay must be used with the VITEK REVEAL AST System, Software Version 1.2.5 or higher.
# IV Device/System Characteristics:
# A Device Description:
The VITEK REVEAL AST System is an in vitro diagnostic (IVD) automated platform for phenotypic Antimicrobial Susceptibility Testing (AST) of bacterial samples, directly from positive blood cultures. The System utilizes growth-based broth microdilution (BMD) principles to rapidly determine Minimum Inhibitory Concentrations (MIC) for the drugs on the VITEK REVEAL GN AST Assay. In combination with species identification (obtained from an FDA-cleared rapid bacterial identification method), the system will provide a Susceptible /
K230675 - Page 6 of 47
{6}
Intermediate / Resistant (“SIR”) and/or extended-spectrum β-lactamase (ESBL) determination for the species tested. The VITEK REVEAL AST System is indicated for susceptibility testing of specific pathogenic bacteria commonly associated with bacteremia.
The VITEK REVEAL AST System detects bacterial growth using an array of chemical Small Molecule Sensors (SMS), which change color in the presence of various metabolic gases (VOC; volatile organic compounds) emitted by growing bacteria during incubation. The SMS arrays, printed onto a VITEK REVEAL Sensor Panel, are positioned atop each well of an inoculated VITEK REVEAL Antibiotic Panel in an AST disposable assembly comprising a VITEK REVEAL GN AST Assay.
There are four key components unique to the VITEK REVEAL AST System: 1) VITEK REVEAL Antibiotic Panels; 2) VITEK REVEAL Sensor Panel; 3) VITEK REVEAL Sealer; 4) VITEK REVEAL Instrument. In addition, the provided inoculator is required for inoculation of the VITEK REVEAL Antibiotic Panels.
Reporting of VITEK REVEAL AST results requires a species identification, which can be obtained by using an FDA-cleared bacterial identification method.
### B Principle of Operation:
The VITEK REVEAL sensor technology is based on novel, proprietary chemical Small Molecule Sensors (SMS) that sensitively register a “fingerprint” of complex volatile compound mixtures. The sensors comprising the array have distinct chemical reactivity with volatiles and changes color upon exposure to low concentrations of volatile organic compounds (VOCs) emitted by populations of microorganisms during growth.
The VITEK REVEAL AST System leverages this sensitive capability to detect growth, using an array of seven sensors positioned over each well of a 96-well antibiotic panel. Thus, the VITEK REVEAL Sensor Panels consist of a sheet of 96, 7-sensor arrays heat-sealed to a 96-well Antibiotic Panel so that when inoculated with bacteria, each array individually responds to the volatiles emitted in that well to sensitively register growth.
Bacterial growth or inhibition in each antimicrobial-containing well is determined by the VITEK REVEAL AST System based on the change in color intensity of the corresponding SMS array compared to the sensor responses in the positive control (no antimicrobials) and negative control (no growth media) wells. An algorithm detects the divergence between the compared SMS responses and rapidly determines growth (indicating resistance) or inhibition (indicating susceptibility) for each two-fold doubling dilution of each antimicrobial thereby enabling a quantitative MIC determination directly analogous to BMD. Once the identification (ID) using a result of an FDA-cleared method is furnished to the system, the MIC result enables the system to generate an interpretation (SIR/ESBL result) based on the FDA-recognized breakpoints. MICs and interpretations are displayed only after the species ID has been entered into the system.
### C Instrument Description Information:
1. Instrument Name:
VITEK REVEAL AST System
K230675 - Page 7 of 47
{7}
# 2. Specimen Identification:
The user enters sample information into the user interface or sample information is transferred to the VITEK REVEAL system via an LIS connection. To ensure sample traceability, the user prints a sample barcode label and places the barcode label on the area of the Sensor Panel where indicated. The sample barcode encodes the sample ID and associated information. There is a separate sensor barcode which encodes the sensor/array information.
# 3. Specimen Sampling and Handling:
The workflow requires an aliquot from a positive blood culture sample that has been confirmed to be Gram-negative and monomicrobial by a Gram stain. The aliquot is diluted into a tube of Pluronic water and the Pluronic suspension is poured into the provided inoculator tray. The provided inoculator is used to dispense the suspension into each well of the 96-well VITEK REVEAL Antibiotic Panel. A VITEK REVEAL Sensor Panel is then placed onto the Antibiotic Panel, and the VITEK REVEAL Sealer seals the Sensor Panel onto the Antibiotic Panel such that an array of seven (7) sensors is positioned over each well. The sealed Antibiotic Panel is then loaded on the VITEK REVEAL Instrument. The VITEK REVEAL Instrument will automatically begin the run. Any time after the run has started, the species ID may be entered into the system. The MIC determinations and SIR/ESBL interpretations are visible on the user interface.
# 4. Calibration:
The VITEK REVEAL Instrument and software has the following internal Quality Control (QC) checks:
- • VITEK REVEAL Instrument drawer incubation temperature has low and high limits that, when exceeded, will display alarms on the user interface.
- • Should either the sensor barcode or sample barcode be unreadable, a default artificial barcode would be assigned, using the instrument ID, plate location, and the current timestamp. An alert will be displayed on the user interface, and the user will have the option to enter the information manually.
- • If the instrument does not identify or cannot locate the 96 well plate, an alert is provided to the user to examine the plate to confirm it is placed correctly in the instrument.
- • If the initial intensity of a sensor is above a certain threshold, it suggests poor quality of the sensor and the user is alerted to retest the sample using a sensor from a new lot. If sensor quality is affected only in certain wells, then the result for the affected antibiotic alone will be suppressed.
- • If there is insufficient growth in the positive control well, then no results are reported, the user is alerted to the possibility of insufficient inoculum or a slow growing organism, and the user is advised to retest the sample.
- • If there is growth detected in the negative control well, then a warning message is displayed on the user interface to alert the user.
- • Each VOC sensor has a QC check to ensure that the sensor quality is acceptable. If a particular sensor fails this check in any well, then that sensor is not used.
# 5. Quality Control:
In addition to the above controls, QC testing of the VITEK REVEAL Instrument and the Sealer should be performed as dictated by the laboratory's protocols. The purpose of external Quality Control (QC) testing is to monitor performance of the VITEK REVEAL AST
K230675 - Page 8 of 47
{8}
System (including the Sensor Panels and Antibiotic Panels) and the VITEK REVEAL Sealer, as well as the proficiency of the laboratory personnel who use the system.
VITEK REVEAL AST System QC is performed by testing the manufacturer recommended QC strains. The QC workflow follows the same steps as the sample workflow, with the exception that provided QC sample barcodes are placed on the GN AST assay, which automatically instructs the instrument to operate in QC mode. The QC results are generated and displayed on the user interface indicating the expected QC MIC range, the VITEK REVEAL MIC call, and whether the relevant antimicrobials for the organism have passed or failed. See more details about quality control in section VII.A. below.
## V Substantial Equivalence Information:
### A Predicate Device Name(s):
Accelerate Pheno system, Accelerate Phenotest BC Kit
### B Predicate 510(k) Number(s):
K192665
### C Comparison with Predicate(s):
| Device & Predicate Device(s): | VITEK REVEAL AST System and VITEK REVEAL GN AST Assay K230675 | Accelerate Pheno System and PhenoTest BC Kit K192665 |
| --- | --- | --- |
| Device Trade Name | VITEK REVEAL GN AST Assay and VITEK REVEAL AST System | Accelerate Pheno System and PhenoTest BC Kit |
| **General Device Characteristic Similarities** | | |
| Intended Use/Indications For Use | The VITEK REVEAL AST System is an *in vitro* diagnostic (IVD) automated system for quantitative and qualitative antimicrobial susceptibility testing (AST) of organisms direct from positive blood culture. The VITEK REVEAL AST System does not provide organism identification. | The Accelerate PhenoTest BC kit is a multiplexed *in vitro* diagnostic test utilizing both qualitative nucleic acid fluorescence in situ hybridization (FISH) identification and quantitative, antimicrobial susceptibility testing (AST) methods and is intended for use with the Accelerate Pheno system. The Accelerate PhenoTest BC kit is capable of simultaneous detection and identification of multiple microbial targets followed by susceptibility testing of the appropriate detected bacterial organisms. The Accelerate PhenoTest BC |
K230675 - Page 9 of 47
{9}
| Device & Predicate Device(s): | VITEK REVEAL AST System and VITEK REVEAL GN AST Assay K230675 | Accelerate Pheno System and PhenoTest BC Kit K192665 |
| --- | --- | --- |
| | | kit is performed directly on blood culture samples identified as positive by a continuous monitoring blood culture system. Results are intended to be interpreted in conjunction with Gram stain results. |
| Indicated Organisms | Gram-negative organisms | Same |
| Type of Test | Automated incubation and reading | Same |
| Sample | Dilution (aliquot) from a positive blood culture as identified by a continuous monitoring blood culture system | Same |
| Inoculum Method | Manual | Same |
| General Device Characteristic Differences | | |
| Time to AST Result | Approximately 8 hours | Approximately 7 hours |
| IVD Function | AST | ID and AST |
| AST Panel Preparation | Manual | Automated |
| Antimicrobial Agents | Amikacin Amoxicillin/clavulanate Ampicillin/sulbactam Aztreonam Cefepime Cefotaxime Cefotaxime/clavulanate Ceftazidime Ceftazidime/avibactam Ceftazidime/clavulanate Ceftolozane/tazobactam Ceftriaxone Cefuroxime Ciprofloxacin Ertapenem Gentamicin Imipenem | Amikacin Ampicillin/sulbactam Aztreonam Cefepime Ceftazidime Ceftriaxone Ciprofloxacin Ertapenem Gentamicin Meropenem Piperacillin/tazobactam Tobramycin |
K230675 - Page 10 of 47
{10}
| Device & Predicate Device(s): | VITEK REVEAL AST System and VITEK REVEAL GN AST Assay K230675 | Accelerate Pheno System and PhenoTest BC Kit K192665 |
| --- | --- | --- |
| | Levofloxacin Meropenem Meropenem/vaborbactam Piperacillin/tazobactam Tetracycline Tobramycin Trimethoprim/sulfamethoxazole | |
| Technology | Growth based analysis, using detection of metabolic byproducts | Morphokinetic cellular analysis (MCA) |
| Results | Report results as minimum inhibitory concentration (MIC), categorical interpretation, and ESBL determination | Report results as minimum inhibitory concentration (MIC), categorical interpretation |
# VI Standards/Guidance Documents Referenced:
1. CLSI Standard M07 11th Ed. Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically (2018)
2. IEC 61326-1:2020 Electromagnetic Immunity, Conducted Immunity, and Class A Electromagnetic Radiation and Conducted Emissions
3. IEC 60601-1-2:2014+AMD1:2020 Electromagnetic Immunity, Medical Equipment
4. IEC 61326-2-6:2020 - Electrical equipment for measurement, control and laboratory use - EMC requirements – Part 2-6
5. IEC 61010-1: 2010 3rd Edition - Safety requirements for electrical equipment for measurement, control, and laboratory use - Part 1
6. IEC 61010-2-101:2018 3rd Edition - Safety requirements for electrical equipment for measurement, control, and laboratory use
7. IEC 61010-2-010:2019 4th Edition - Safety requirements for electrical equipment for measurement, control and laboratory use
8. FCC Part 15 Subpart B Electromagnetic Radiation and Conducted Emissions
9. CLSI supplement EP37. Supplemental Tables for Interference Testing in Clinical Chemistry 1st ed; 2018
10. CLSI supplement M100 32nd, 33rd, and 34th Ed. Performance Standards for Antimicrobial Susceptibility Testing; 2022, 2023, 2024
11. FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility (AST) Systems: Guidance for Industry and FDA (Issued August 28, 2009). General Principles of Software Validation; Final Guidance for Industry and FDA Staff
K230675 - Page 11 of 47
{11}
1. 12. Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices. Issued May 11, 2005.
2. 13. Electromagnetic Compatibility (EMC) of Medical Devices: Guidance for Industry and Food and Drug Administration Staff. Issued June 6, 2022.
3. 14. Guidance for Industry: Cybersecurity for Networked Medical Devices Containing Off-the-Shelf (OTS) Software. Issued January 14, 2005
4. 15. Content of Premarket Submissions for Management of Cybersecurity in Medical Devices: Guidance for Industry and Food and Drug Administration Staff. Issued October 2, 2014
5. 16. Post market Management of Cybersecurity in Medical Devices: Guidance for Industry and Food and Drug Administration Staff. Issued December 28, 2016.
6. 17. Off-The-Shelf Software Use in Medical Devices: Guidance for Industry and Food and Drug Administration Staff. Issued September 27, 2019.
## VII Performance Characteristics (if/when applicable):
### A Analytical Performance:
#### 1. Precision/Reproducibility:
Reproducibility testing for the VITEK REVEAL GN AST Assay was conducted at three sites (two external and one internal site) by evaluating eighty-two (82) Gram-negative isolates, generally representing indicated organisms, that provided at least 10 organisms with on-scale MIC results for each antibiotic on the VITEK REVEAL Antibiotic panels. Isolates were tested in one of three VITEK REVEAL antibiotic panels (VITEK REVEAL SGN1, VITEK REVEAL SGN2, or VITEK REVEAL SGN3) as shown in **Table 1**. Each isolate was tested in triplicate over three days ($\geq 10$ isolates x 3 sites x 3 replicates x 3 days = $\geq 270$ results per antibiotic). Isolates were spiked into blood culture bottles containing human blood and incubated until positivity. Three inoculum dilutions were prepared from each positive blood culture aliquot and used to inoculate the three VITEK REVEAL Antibiotic Panels. The mode of MIC values was determined for each isolate. Reproducibility was determined from the total number (and percent) of results that were within one dilution (+/- one doubling dilution) of the modal MIC result divided by the total number of results.
For trimethoprim/sulfamethoxazole, only five isolates were tested due to the lack of isolates with on-scale MICs; however, the five isolates were tested on six days rather than three to achieve the appropriate number of replicates.
Both best-case (assumes that off-scale results are less than one dilution from the mode) and worst-case (assumes that off-scale results are more than one dilution from the mode) performance was determined for each antimicrobial agent, as outlined in the AST Special Controls Guidance. The best-case reproducibility for each antimicrobial was $\geq 95\%$, which is acceptable. Worst-case reproducibility was $\geq 89\%$ for all antibiotics, which is acceptable. Results of the reproducibility are summarized in **Table 2**.
K230675 - Page 12 of 47
{12}
Table 1. Plate configuration for the VITEK REVEAL AST System
| VITEK REVEAL SGN1 Antibiotics | VITEK REVEAL SGN2 Antibiotics | VITEK REVEAL SGN3 Antibiotics |
| --- | --- | --- |
| Ampicillin/sulbactam | Amikacin | Amoxicillin/clavulanate |
| Cefotaxime | Gentamicin | Cefepime |
| Ceftazidime | Tobramycin | Tetracycline |
| Ceftazidime/avibactam | Aztreonam | Ciprofloxacin |
| Ceftolozane/tazobactam | Ertapenem | Levofloxacin |
| Cefuroxime | Imipenem | |
| Ceftriaxone | Meropenem | |
| ESBL* | Meropenem/vaborbactam | |
| | Piperacillin/tazobactam | |
| | Trimethoprim/sulfamethoxazole | |
*Assay used to determine extended-spectrum β-lactamase (ESBL) status for the species tested.
Table 2. Summary of results by antibiotic with best and worst-case reproducibility across all sites.
| Antibiotic | Best case # | Best case % | Worst case # | Worst case % |
| --- | --- | --- | --- | --- |
| Ampicillin/sulbactam* | 269/270 | 99.6% | 266/270 | 98.5% |
| Cefotaxime | 342/351 | 97.4% | 342/351 | 97.4% |
| Ceftazidime* | 395/396 | 99.7% | 395/396 | 99.7% |
| Ceftazidime/avibactam* | 345/350 | 98.6% | 345/350 | 98.6% |
| Ceftolozane/tazobactam* | 564/565 | 99.8% | 564/565 | 99.8% |
| Cefuroxime | 429/429 | 100.0% | 427/429 | 99.5% |
| Ceftriaxone | 267/267^ | 100.0% | 259/267 | 97.0% |
| ESBL confirmation | 529/540 | 98.0% | N/A | N/A |
| Amikacin | 891/891 | 100.0% | 870/891 | 97.6% |
| Gentamicin | 538/538 | 100.0% | 523/538 | 97.2% |
| Tobramycin | 808/809 | 99.9% | 807/809 | 99.8% |
| Aztreonam* | 287/296 | 97.0% | 287/296 | 97.0% |
| Ertapenem* | 291/297 | 98.0% | 291/297 | 98.0% |
| Imipenem | 397/397 | 100.0% | 364/397 | 91.7% |
| Meropenem | 404/405 | 99.8% | 395/405 | 97.5% |
| Meropenem/vaborbactam | 285/297 | 96.0% | 285/297 | 96.0% |
| Piperacillin/tazobactam | 377/377 | 100.0% | 368/377 | 97.6% |
| Trimethoprim/sulfamethoxazole | 269/269^ | 100.0% | 263/269 | 97.8% |
K230675 - Page 13 of 47
{13}
| Antibiotic | Best case # | Best case % | Worst case # | Worst case % |
| --- | --- | --- | --- | --- |
| Amoxicillin/clavulanate | 324/324 | 100.0% | 323/324 | 99.7% |
| Cefepime | 371/377 | 98.4% | 360/377 | 95.5% |
| Tetracycline | 297/297 | 100.0% | 291/297 | 98.0% |
| Ciprofloxacin | 319/324 | 98.5% | 319/324 | 98.5% |
| Levofloxacin | 323/323 | 100.0% | 323/323 | 100.0% |
*Analysis includes non-indicated species.
^ Indeterminate results generated from one or more isolates were excluded from the analysis.
# 2. Linearity:
Not applicable
# 3. Analytical Specificity/Interference:
# Exogenous/Exogenous Interference Studies
An interfering substances study was performed to evaluate if substances naturally present or artificially introduced into blood culture bottles affect VITEK REVEAL GN AST Assay and VITEK REVEAL AST System performance. Organisms evaluated included representative strains of each indicated organism group: Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacter cloacae. Potential interferents were spiked into BD BACTEC Aerobic Plus blood culture bottles at or above clinically relevant concentrations along with representative organisms. Control bottles were seeded with organism and no potential interferent. Bottles were incubated in a continuous monitoring blood culture system until positivity. As this is a method-to-method comparison, determined by comparing MIC results from the interferent-containing samples with the modal MIC of the control samples, and essential agreement (EA) of ≥95% was deemed acceptable.
A total of 184 interferent-antibiotic combinations were tested on the VITEK REVEAL AST system. Overall, the presence of high concentrations of these interferents in blood cultures does not interfere with the results of the VITEK REVEAL AST system (Tables 3 & 4). There were a few instances in which EA was <95% for specific interferents, discussed below:
Ceftazidime in the presence of hemolysate (RBC), sodium citrate, and triglycerides (LPD) (tested individually) had an EA < 95% due to one replicate of K. pneumoniae being out of EA. In each instance, one replicate of K. pneumoniae was out of EA yet was within category agreement (CA), and thus is not expected to impact patient care. In addition, variable MIC values were attributed to this strain's growth pattern detection by the system. This is noted in a footnote in the device labeling.
Meropenem in the presence of heparin had an EA < 95% for K. pneumoniae due to one replicate being out of EA. However, this result is within category agreement (CA), and thus is not expected to impact patient care. This is noted in a footnote in the device labeling.
K230675 - Page 14 of 47
{14}
Meropenem/Vaborbactam in the presence of triglycerides (LPD) had an EA <95% for E. cloacae due to one replicate being out of EA. Upon repeat testing, the EA was found to be 100% This is noted in a footnote in the device labeling.
Meropenem/Vaborbactam in the presence of heparin had an EA <95% for K. pneumoniae due to one replicate being out of EA. However, this result is within category agreement (CA), and thus is not expected to impact patient care. This is noted in a footnote in the device labeling.
Ceftazidime/Avibactam in the presence of hemolysate (RBC) had an EA <95% for P. aeruginosa due to one replicate being out of EA. However, this result is within category agreement (CA), and thus is not expected to impact patient care. This is noted in a footnote in the device labeling.
Ceftriaxone in the presence of heparin had an EA <95% for K. pneumoniae. The low EA was due to one replicate being out of EA. Upon repeat testing, the EA was found to be 100%. This is noted in a footnote in the device labeling.
In addition, organisms with on-scale MIC values were not tested for several antibiotic/organism group combinations with all the potential interfering substances, except platelets. The following limitation is included in the device labeling:
Interference has not been established for the following drug/organism combination for all interferents, except platelets: amoxicillin-clavulanate/Enterobacterales, aztreonam/Enterobacterales, cefepime/Enterobacterales, ceftazidime/Enterobacterales, ceftriaxone/Enterobacterales, ciprofloxacin/P. aeruginosa, levofloxacin/P. aeruginosa, ertapenem/Enterobacterales, imipenem/Enterobacterales.
Table 3. Overall Performance with Potential Interferents (part 1).
| Antimicrobial | Red Blood Cells (≥200 mg/mL) | | White Blood Cells (≥ 1.2 x 10⁷/mL) | | Platelets (>400,000/μL) | | Gamma Globulins (≥ 20 mg/mL) | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | # EA / Total | % EA | # EA / Total | % EA | # EA / Total | % EA | # EA / Total | % EA |
| Amikacin | 15/15 | 100.0% | 15/15 | 100.0% | 48/48 | 100.0% | 15/15 | 100.0% |
| Amoxicillin-Clavulanate | 9/9 | 100.0% | 9/9 | 100.0% | 36/36 | 100.0% | 9/9 | 100.0% |
| Ampicillin-Sulbactam | 9/9 | 100.0% | 9/9 | 100.0% | 36/36 | 100.0% | 9/9 | 100.0% |
| Aztreonam | 12/12 | 100.0% | 12/12 | 100.0% | 45/45 | 100.0% | 12/12 | 100.0% |
| Cefepime | 12/12 | 100.0% | 12/12 | 100.0% | 42/42 | 100.0% | 12/12 | 100.0% |
| Cefotaxime | 12/12 | 100.0% | 12/12 | 100.0% | 42/42 | 100.0% | 12/12 | 100.0% |
| Ceftazidime | 14/15 | 93.3%* | 15/15 | 100.0% | 48/48 | 100.0% | 15/15 | 100.0% |
| Ceftazidime/Avibactam | 11/12 | 91.7%* | 12/12 | 100.0% | 45/45 | 100.0% | 11/11 | 100.0% |
| Ceftolozane/Tazobactam | 12/12 | 100.0% | 12/12 | 100.0% | 45/45 | 100.0% | 12/12 | 100.0% |
| Ceftriaxone | 9/9 | 100.0% | 8/8 | 100.0% | 39/39 | 100.0% | 9/9 | 100.0% |
| Cefuroxime | 6/6 | 100.0% | 6/6 | 100.0% | 33/33 | 100.0% | 6/6 | 100.0% |
| Ciprofloxacin | 12/12 | 100.0% | 12/12 | 100.0% | 42/42 | 100.0% | 12/12 | 100.0% |
| Ertapenem | 9/9 | 100.0% | 8/8 | 100.0% | 40/42 | 95.2% | 9/9 | 100.0% |
| ESBL** | 6/6 | 100.0% | 6/6 | 100.0% | 33/33 | 100.0% | 6/6 | 100.0% |
| Gentamicin | 12/12 | 100.0% | 12/12 | 100.0% | 45/45 | 100.0% | 12/12 | 100.0% |
| Imipenem | 15/15 | 100.0% | 15/15 | 100.0% | 48/48 | 100.0% | 15/15 | 100.0% |
| Levofloxacin | 12/12 | 100.0% | 12/12 | 100.0% | 42/42 | 100.0% | 12/12 | 100.0% |
| Meropenem | 15/15 | 100.0% | 15/15 | 100.0% | 48/48 | 100.0% | 15/15 | 100.0% |
K230675 - Page 15 of 47
{15}
| Antimicrobial | Red Blood Cells (≥200 mg/mL) | | White Blood Cells (≥ 1.2 x 10⁹/mL) | | Platelets (>400,000/μL) | | Gamma Globulins (≥ 20 mg/mL) | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | # EA / Total | % EA | # EA / Total | % EA | # EA / Total | % EA | # EA / Total | % EA |
| Meropenem/Vaborbactam | 9/9 | 100.0% | 9/9 | 100.0% | 42/42 | 100.0% | 9/9 | 100.0% |
| Piperacillin/Tazobactam | 15/15 | 100.0% | 15/15 | 100.0% | 48/48 | 100.0% | 15/15 | 100.0% |
| Tetracycline | 9/9 | 100.0% | 9/9 | 100.0% | 42/42 | 100.0% | 9/9 | 100.0% |
| Tobramycin | 12/12 | 100.0% | 12/12 | 100.0% | 45/45 | 100.0% | 12/12 | 100.0% |
| Trimethoprim/Sulfamethoxazole | 9/9 | 100.0% | 9/9 | 100.0% | 42/42 | 100.0% | 9/9 | 100.0% |
| * Low EA was due to one replicate being out of EA yet was within category agreement (CA). |
| --- |
| **Assay is qualitative. Values reported in the table are %CA. |
* Low EA was due to one replicate being out of EA yet was within category agreement (CA).
**Assay is qualitative. Values reported in the table are %CA.
Table 4. Overall Performance with Potential Interferents (part 2)
| Antimicrobial | Conjugated bilirubin (≥ 0.02 mg/mL) | | Triglycerides (≥ 15 mg/mL) | | Heparin (≥ 3 units/mL) | | Sodium Citrate (> 6% w/v) | | Sodium Polyanetholsulfonate (> 2% w/v) | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| | # EA / Total | % EA | # EA / Total | % EA | #EA/ Total | % EA | #EA/ Total | % EA | #EA/ Total | % EA |
| Amikacin | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% |
| Amoxicillin-Clavulanate | 9/9 | 100.0% | 9/9 | 100.0% | 5/5 | 100.0% | 5/5 | 100.0% | 9/9 | 100.0% |
| Ampicillin-Sulbactam | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% |
| Aztreonam | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% |
| Cefepime | 12/12 | 100.0% | 12/12 | 100.0% | 11/11 | 100.0% | 11/11 | 100.0% | 12/12 | 100.0% |
| Cefotaxime | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% |
| Ceftazidime | 15/15 | 100.0% | 13/15 | 86.7%* | 15/15 | 100.0% | 12/15 | 80.0%* | 15/15 | 100.0% |
| Ceftazidime/Avibactam | 11/11 | 100.0% | 11/11 | 100.0% | 11/11 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% |
| Ceftoazone/Tazobactam | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% |
| Ceftriaxone | 9/9 | 100.0% | 9/9 | 100.0% | 8/9 | 88.9%^ | 9/9 | 100.0% | 9/9 | 100.0% |
| Cefuroxime | 6/6 | 100.0% | 6/6 | 100.0% | 6/6 | 100.0% | 6/6 | 100.0% | 6/6 | 100.0% |
| Ciprofloxacin | 12/12 | 100.0% | 12/12 | 100.0% | 11/11 | 100.0% | 11/11 | 100.0% | 12/12 | 100.0% |
| Ertapenem | 9/9 | 100.0% | 8/8 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% |
| ESBL** | 6/6 | 100.0% | 6/6 | 100.0% | 6/6 | 100.0% | 6/6 | 100.0% | 6/6 | 100.0% |
| Gentamicin | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% |
| Imipenem | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% |
| Levofloxacin | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 11/11 | 100.0% | 10/10 | 100.0% |
| Meropenem | 15/15 | 100.0% | 15/15 | 100.0% | 14/15 | 93.3%* | 15/15 | 100.0% | 15/15 | 100.0% |
| Meropenem/Vaborbactam | 15/15 | 100.0% | 8/9 | 88.9%^ | 8/9 | 88.9%* | 9/9 | 100.0% | 9/9 | 100.0% |
| Piperacillin/Tazobactam | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% | 15/15 | 100.0% |
| Tetracycline | 9/9 | 100.0% | 9/9 | 100.0% | 8/8 | 100.0% | 8/8 | 100.0% | 9/9 | 100.0% |
| Tobramycin | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% | 12/12 | 100.0% |
| Trimethoprim/Sulfamethoxazole | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% | 9/9 | 100.0% |
* Low EA was due to one replicate being out of EA yet was within category agreement (CA).
** Assay is qualitative. Values reported in the table is %CA.
^ Upon repeat testing, %EA was 100%.
### Antimicrobial Interference Studies:
VITEK REVEAL GN AST Assay and VITEK REVEAL AST System performance was assessed using seeded positive blood culture samples with and without interfering antimicrobials. At least one representative organism from each claimed organism reporting group (i.e., Proteus mirabilis, Escherichia coli, Acinetobacter baumannii, Enterobacter cloacae, Citrobacter freundii, and Serratia marcescens) were evaluated with each claimed antimicrobial. One (1) antibiotic from nine (9) of the main classes of antibiotics that target Gram-negative organisms was tested as the interfering agent (i.e., ampicillin, ampicillin/sulbactam, aztreonam, cefotaxime, meropenem, ciprofloxacin, trimethoprim/sulfamethoxazole, tetracycline, and gentamicin). Antimicrobial interferents were spiked into blood culture bottles at or above clinically relevant concentrations along
K230675 - Page 16 of 47
{16}
with relevant organisms. A minimum of one (1) Gram-negative strain resistant to each interfering antimicrobial was tested in triplicate in BD BACTEC Standard aerobic bottles, which do not contain resins and do not have neutralization capabilities. Control bottles were seeded with organism and no antimicrobial interferent. Bottles were incubated in a continuous monitoring blood culture system until positivity. As this is a method-to-method comparison, essential agreement (EA) of ≥95% was deemed acceptable.
A total of 229 antimicrobial interferent-antibiotic combinations were tested on the VITEK REVEAL AST System. In general, the data were acceptable with 100% EA. There was one instance in which EA was <95% for a specific interferent, discussed below:
When the interferent ampicillin/sulbactam (150/88 μg/ml) was incubated with E. coli, ertapenem (EA 50%), meropenem (EA 66.7%), piperacillin/tazobactam (EA 66.7%), and trimethoprim/sulfamethoxazole (EA 83.3%) demonstrated an EA less than 95%. Based on growth patterns for these instances, it appears the ampicillin/sulbactam was interfering with the growth of the E. coli. Testing was repeated with a lower concentration of ampicillin/sulbactam (75/44 μg/ml) and the interference was not observed. In addition, a second E. coli strain was tested and the interference was not observed. This suggests that interference from ampicillin/sulbactam is possible for some E. coli strains and may be strain specific. This is noted in a footnote in the device labeling.
The following antibiotic pairs were not evaluated due to intrinsic resistance of the strains tested or the test was not indicted: ampicillin with tetracycline, imipenem, and trimethoprim/sulfamethoxazole; cefotaxime with ESBL; meropenem with ESBL; gentamicin with amoxicillin/clavulanate, ampicillin/sulbactam, cefuroxime, ESBL, piperacillin/tazobactam, imipenem, and ceftolozane/tazobactam; tetracycline with amoxicillin/clavulanate, ampicillin/sulbactam, ceftolozane/tazobactam, cefuroxime, and ESBL; trimethoprim/sulfamethoxazole and ESBL; and ciprofloxacin with ESBL.
# 4. Assay Reportable Range:
Not applicable
# 5. Traceability, Stability, Expected Values (Controls, Calibrators, or Methods):
Quality Control Testing. Quality control testing was performed each day that testing was conducted. CLSI recommended or independently validated QC strains for each antimicrobial were tested a sufficient number of times (i.e., at least 20 times/site) at each testing site using the VITEK REVEAL AST System and at the reference site using the broth microdilution reference method.
For all antimicrobials, greater than 95% of results were within the expected range, which is acceptable (Table 5.).
K230675 - Page 17 of 47
{17}
Table 5. QC Expected Ranges and Results for the VITEK REVEAL GN AST Assay
| Antimicrobial | QC Organism | VITEK REVEAL Expected Range (μg/mL) | No. in Range (%) | |
| --- | --- | --- | --- | --- |
| | | | Reference | VITEK REVEAL AST |
| Amikacin | *E. coli* ATCC 25922 | ≤ 0.5-4 | 104/104 (100%) | 179/183 (97.8%) |
| | *P. aeruginosa* ATCC 27853 | 1-4 | 105/105 (100%) | 176/176 (100%) |
| Amoxicillin-Clavulanate | *E. coli* ATCC 25922* | ≤2/1-8/4 | 95/95 (100%) | 175/178 (98.3%) |
| | *K. pneumoniae* ATCC 700603 | 4/4-16/8 | 92/92 (100%) | 166/166 (100%) |
| Ampicillin-Sulbactam | *E. coli* ATCC 25922* | ≤2/1-8/4 | 98/98 (100%) | 183/186 (98.4%) |
| | *K. pneumoniae* ATCC 700603 | 8/4-32/16 | 92/92 (100%) | 165/165 (100%) |
| Aztreonam | *E. coli* ATCC 25922* | ≤0.25 | 103/104 (99.0%) | 176/179 (98.3%) |
| | *P. aeruginosa* ATCC 27853 | 2-8 | 101/105 (96.2%) | 177/177 (100%) |
| | *K. pneumoniae* ATCC 700603 | 8-64 | 99/101 (98.0%) | 163/164 (99.3%) |
| Cefepime | *E. coli* ATCC 25922* | ≤0.125 | 110/113 (97.3%) | 174/177 (98.3%) |
| | *P. aeruginosa* ATCC 27853 | 0.5-4 | 113/113 (100%) | 181/181 (100%) |
| | *K. pneumoniae* ATCC 700603 | 0.5-2 | 108/109 (99.1%) | 165/165 (100%) |
| Cefotaxime | *E. coli* ATCC 25922* | ≤0.25 | 113/116 (97.4%) | 183/186 (98.4%) |
| | *P. aeruginosa* ATCC 27853 | 8-32 | 108/114 (94.7%) | 171/174 (98.3%) |
| Ceftazidime | *E. coli* ATCC 25922* | ≤0.125-0.5 | 114/116 (98.3%) | 184/187 (98.4%) |
| | *P. aeruginosa* ATCC 27853 | 1-4 | 112/114 (98.2%) | 170/171 (99.4%) |
| | *K. pneumoniae* ATCC 700603 | 16-64 | 109/109 (100%) | 163/164 (99.4%) |
| Ceftazidime-Avibactam | *E. coli* ATCC 25922* | ≤0.06/4-0.5/4 | 115/116 (99.1%) | 184/187 (98.4%) |
| | *P. aeruginosa* ATCC 27853 | 0.5/4-4/4 | 113/114 (99.1%) | 175/175 (100%) |
| | *K. pneumoniae* ATCC 700603 | 0.25/4-2/4 | 107/109 (98.2%) | 164/165 (99.4%) |
K230675 - Page 18 of 47
{18}
| Antimicrobial | QC Organism | VITEK REVEAL Expected Range (μg/mL) | No. in Range (%) | |
| --- | --- | --- | --- | --- |
| | | | Reference | VITEK REVEAL AST |
| Ceftolozane-Tazobactam | *E. coli* ATCC 25922 | 0.125/4-0.5/4 | 125/128 (97.7%) | 183/186 (98.4%) |
| | *P. aeruginosa* ATCC 27853 | 0.25/4-1/4 | 121/126 (96.0%) | 175/175 (100%) |
| | *K. pneumoniae* ATCC 700603 | 0.5/4-2/4 | 117/120 (97.5%) | 164/164 (100%) |
| Ceftriaxone | *P. aeruginosa* ATCC 27853* | 8->16 | 114/114 (100%) | 174/174 (100%) |
| | *K. pneumoniae* ATCC 700603** | 2-8 | 103/107 (96.3%) | 163/163 (100%) |
| Cefuroxime | *E. coli* ATCC 25922 | 2-8 | 106/106 (100%) | 182/186 (97.8%) |
| Ciprofloxacin | *E. coli* ATCC 25922* | ≤0.0625 | 110/113 (97.3%) | 175/178 (98.3%) |
| | *P. aeruginosa* ATCC 27853 | 0.125-1 | 111/113 (98.2%) | 177/182 (97.3%) |
| Ertapenem | *E. coli* ATCC 25922* | ≤0.125 | 111/113 (98.2%) | 178/182 (97.8%) |
| | *P. aeruginosa* ATCC 27853 | 2-8 | 108/114 (94.7%) | 175/176 (99.4%) |
| Gentamicin | *E. coli* ATCC 25922* | ≤0.25-1 | 103/104 (99.0%) | 183/183 (100%) |
| | *P. aeruginosa* ATCC 27853 | 0.5-2 | 104/105 (99.0%) | 177/177 (100%) |
| Imipenem | *E. coli* ATCC 25922* | ≤0.25-0.5 | 103/104 (99.0%) | 178/182 (97.8%) |
| | *P. aeruginosa* ATCC 27853 | 1-4 | 104/105 (99.0%) | 174/175 (99.4%) |
| | *K. pneumoniae* ATCC 700603* | ≤0.25-0.5 | 100/101 (99.0%) | 164/164 (100%) |
| Levofloxacin | *E. coli* ATCC 25922* | ≤0.125 | 111/113 (98.2%) | 176/178 (98.8%) |
| | *P. aeruginosa* ATCC 27853 | 0.5-4 | 111/113 (98.2%) | 174/182 (95.6%) |
| Meropenem | *E. coli* ATCC 25922* | ≤0.0625 | 104/104 (100%) | 179/183 (97.8%) |
| | *P. aeruginosa* ATCC 27853 | 0.125-1 | 104/105 (99.0%) | 175/176 (99.4%) |
| | *K. pneumoniae* ATCC BAA-2814* | ≥32 | 98/98 (100%) | 196/197 (99.4%) |
| Meropenem-Vaborbactam | *E. coli* ATCC 25922* | ≤0.0625/8 | 103/104 (99.0%) | 179/183 (97.8%) |
K230675 - Page 19 of 47
{19}
| Antimicrobial | QC Organism | VITEK REVEAL Expected Range (μg/mL) | No. in Range (%) | |
| --- | --- | --- | --- | --- |
| | | | Reference | VITEK REVEAL AST |
| | *P. aeruginosa* ATCC 27853 | 0.125/8-1/8 | 103/105 (98.1%) | 177/178 (99.4%) |
| | *K. pneumoniae* ATCC 700603* | ≤0.0625/8 | 100/101 (99.0%) | 165/165 (100%) |
| | *K. pneumoniae* ATCC BAA-2814 | 0.125/8-0.5/8 | 89/98^ (90.8%) | 190/197 (96.4%) |
| Piperacillin-Tazobactam | *E. coli* ATCC 25922* | ≤2/4-8/4 | 111/112 (99.1%) | 178/183 (95.7%) |
| | *P. aeruginosa* ATCC 27853* | ≤2/4-8/4 | 112/114 (98.2%) | 177/177 (100%) |
| | *K. pneumoniae* ATCC 700603 | 8/4-32/4 | 107/109 (98.2%) | 165/165 (100%) |
| Tetracycline | *E. coli* ATCC 25922* | ≤1-2 | 95/95 (100%) | 178/178 (100%) |
| | *P. aeruginosa* ATCC 27853 | 8-32 | 95/95 (100%) | 173/181 (95.5%) |
| Tobramycin | *E. coli* ATCC 25922 | 0.25-1 | 102/104 (98.1%) | 179/184 (97.3%) |
| | *P. aeruginosa* ATCC 27853 | 0.25-1 | 105/105 (100%) | 177/177 (100%) |
| Trimethloprim-Sulfamethoxazole | *E. coli* ATCC 25922 | ≤0.5/9.5 | 102/104 (98.1%) | 182/182 (100%) |
| | *P. aeruginosa* ATCC 27853 | 8/52-32/608 | 102/105 (97.1%) | 174/177 (98.3%) |
*VITEK REVEAL expected results are partially or entirely off-scale. Off-scale results were considered acceptable.
** Validation performed for non-CLSI recommended QC strain.
^ Clinical data on days with out-of-range QC results was considered acceptable due to alternative QC strains that tested in-range on the same day.
QC expected and actual results for ESBL determination are summarized in Table 6. The VITEK REVEAL AST System demonstrated 100% concordance with expected results. Overall, QC was determined to be acceptable.
Table 6. QC Results for the VITEK REVEAL AST System for ESBL Determination
| Antimicrobial | QC Organism | Expected Result | No. Correct (%) | |
| --- | --- | --- | --- | --- |
| | | | Reference | REVEAL |
| ESBL Screen | *E. coli* ATCC 25922 | Negative | 94/94 (100) | 183/183 (100) |
| ESBL Screen | *K. pneumoniae* ATCC 700603 | Positive | 88/88 (100) | 157/157 (100) |
### Validation of *K. pneumoniae* ATCC 700603 as an Additional QC Organism for Ceftriaxone on the VITEK REVEAL
To validate the use of *K. pneumoniae* ATCC 700603 as a QC organism with the VITEK REVEAL, 24 replicates of *K. pneumoniae* ATCC 700603 were tested per two lots of the
K230675 - Page 20 of 47
{20}
antimicrobial reagents over two days resulting in 96 data points to determine the BMD range for this combination. All data points fell between 2-8 μg/ml. In the clinical study, an additional 107 data points were tested by BMD for a total of 203 data points with >95% in-range, which supported a QC range of 2-8 μg/ml in the VITEK REVEAL clinical study. When K. pneumoniae ATCC 700603 was tested on the VITEK REVEAL, 217/217 (100%) of the results fell within the QC range of 2-8 μg/ml. Taken together, these data are acceptable to support the use of K. pneumoniae ATCC 700603 as a QC organism when testing ceftriaxone on the VITEK REVEAL.
## Purity Check
Purity plates were prepared from the positive blood cultures of every sample tested. AST results were only reported for pure isolates; data generated from plates that generated multiple colony morphologies was excluded from analyses.
## Device Failure
Seven device failures were observed during validation studies. All were detected at the time of failure by the system and resulted in error messages, thus had no impact on results. Two failures were due to undefined internal system failures resulting in no result reports generated. Three failures were due to no MIC calls due to the system timing out without a result reported. Two failures were technical errors due to a suspected sample switch.
## Growth Failure Rate
There were four growth failures (failed on all three antibiotic panels) on the VITEK REVEAL AST System and one partial growth failure (failed on only one of the three antibiotic panels).
## Specimen Stability
The purpose of this study was to demonstrate that positive blood cultures tested up to 16 hours post positivity (T16) and held at room temperature (RT) or in the blood culture instrument (36°C-37°C) provide accurate results.
Contrived positive blood culture specimens (prepared in BD BACTEC Plus Aerobic/F blood culture bottles and BACT/ALERT FA PLUS Aerobic bottles) containing the recommended blood volume were tested at T0, T8 (eight-ten hours post-positivity), and T16 (16-18 hours post-positivity). Testing up to 18 hours was performed to support the stability at 16 hours post-positivity. Testing was performed in triplicate for each sample at each timepoint and each temperature condition. Resulting MICs were compared to the historical modal broth microdilution MIC. The acceptance criterion was ≥ 89% agreement for EA when compared to the modal MIC of the broth microdilution method. When the EA was below 89%, the modal MIC for the incubation condition and time points was compared to the T0 MIC result to assess the discrepancy. QC was performed each day of testing.
A total of 25 gram-negative isolates with known MICs as determined by broth microdilution testing were evaluated. Species tested included Acinetobacter baumannii (1), E. coli (6), K. pneumoniae (2), K. aerogenes (5), K. oxytoca (3), P. mirabilis (2), S. marcescens (1) and P. aeruginosa (5). Results for all antimicrobials tested were acceptable for stability up to 16 hours when applying the acceptance criteria (Tables 7 & 8) except for the instances below:
K230675 - Page 21 of 47
{21}
- Cefuroxime and *E. coli* at T8 (36°C-37°C) in the BD BACTEC Plus Aerobic/F blood culture bottles,
- Cefuroxime and *E. coli* at T0 (36°C-37°C and RT), T8 (RT) and T16 (RT) in the BACT/ALERT FA PLUS Aerobic bottles, and
- ESBL analysis (CA) and *E. coli* for all conditions except T8 (RT) in the BD BACTEC Plus Aerobic/F bottles.
All instances resulted in an EA/CA of 100% based on comparisons between the T0 and other timepoints obtained by the VITEK REVEAL system. This is noted in a footnote in the device labeling.
As noted in the instructions for use, all blood culture bottle samples should be tested promptly after ringing positive on a continuous monitoring system. In the case of unavoidable delays or if the need for re-testing arises, positive blood culture bottles may be tested up to 16 hours post ring.
**Table 7.** Summary of Sample Stability AST Results at T0, T8, and T16 as compared to the BMD Mode for BD BACTEC Plus Aerobic/F.
| Antimicrobial | Instrument (36°C-37°C) No. EA/Total Tested (EA%) | | | Bench (RT) No. EA/Total Tested (EA%) | | |
| --- | --- | --- | --- | --- | --- | --- |
| | T0 | T8 | T16 | T0 | T8 | T16 |
| Ampicillin/Sulbactam | 18/18 (100%) | 16/16 (100%) | 18/18 (100%) | 18/18 (100%) | 18/18 (100%) | 18/18 (100%) |
| Cefotaxime | 27/27 (100%) | 25/25 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) |
| Ceftazidime | 28/29 (96.5%) | 29/29 (100%) | 30/30 (100%) | 28/29 (96.5%) | 30/30 (100%) | 30/30 (100%) |
| Ceftazidime/Avibactam | 27/27 (100%) | 26/26 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) |
| Ceftolozane/Tazobactam | 27/27 (100%) | 26/26 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) |
| Ceftriaxone | 22/24 (91.7%) | 24/24 (100%) | 24/24 (100%) | 22/24 (91.7%) | 24/24 (100%) | 24/24 (100%) |
| Cefuroxime | 15/15 (100%) | 12/14* (85.7%) | 14/15 (93.3%) | 15/15 (100%) | 15/15 (100%) | 15/15 (100%) |
| ESBL** | 11/14* (78.6%) | 12/14* (85.7%) | 13/15* (86.6%) | 11/14* (78.6%) | 15/15 (100%) | 12/15* (80.0%) |
| Amikacin | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) |
| Aztreonam | 29/30 (96.7%) | 29/30 (96.7%) | 30/30 (100%) | 29/30 (96.7%) | 27/29 (93.1%) | 30/30 (100%) |
| Ertapenem | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) |
| Gentamicin | 30/30 (100%) | 28/30 (93.3%) | 30/30 (100%) | 30/30 (100%) | 28/30 (93.3%) | 29/30 (96.7%) |
| Imipenem | 27/27 (100%) | 26/26 (100%) | 26/26 (100%) | 27/27 (100%) | 25/26 (96.1%) | 26/26 (100%) |
K230675 - Page 22 of 47
{22}
| Antimicrobial | Instrument (36°C-37°C) No. EA/Total Tested (EA%) | | | Bench (RT) No. EA/Total Tested (EA%) | | |
| --- | --- | --- | --- | --- | --- | --- |
| | T0 | T8 | T16 | T0 | T8 | T16 |
| Meropenem | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 29/30 (96.7%) | 29/29 (100%) |
| Meropenem/Vaborbactam | 24/24 (100%) | 23/24 (95.8%) | 24/24 (100%) | 24/24 (100%) | 22/23 (95.6%) | 23/23 (100%) |
| Piperacillin/Tazobactam | 28/30 (93.3%) | 30/30 (100%) | 30/30 (100%) | 28/30 (93.3%) | 29/30 (96.7%) | 30/30 (100%) |
| Tobramycin | 30/30 (100%) | 27/30 (90.0%) | 30/30 (100%) | 30/30 (100%) | 29/30 (96.7%) | 30/30 (100%) |
| Trimethoprim/ Sulfamethoxazole | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) |
| Amoxicillin/Clavulanate | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 11/11 (100%) | 12/12 (100%) |
| Cefepime | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) |
| Ciprofloxacin | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) |
| Levofloxacin | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) |
| Tetracycline | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) |
* As described above, comparison to T0 and other timepoints resulted in an EA/CA of 100%.
** Assay is qualitative. Values reported in the table is %CA.
Table 8. Summary of Sample Stability AST Results at T0, T8, and T16 as compared to the BMD Mode for BACT/ALERT FA PLUS Aerobic.
| Antimicrobial | Instrument (36°C-37°C) No. EA/Total Tested (EA%) | | | Bench (RT) No. EA/Total Tested (EA%) | | |
| --- | --- | --- | --- | --- | --- | --- |
| | T0 | T8 | T16 | T0 | T8 | T16 |
| Ampicillin/Sulbactam | 18/18 (100%) | 18/18 (100%) | 18/18 (100%) | 18/18 (100%) | 18/18 (100%) | 18/18 (100%) |
| Cefotaxime | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) |
| Ceftazidime | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) |
| Ceftazidime/Avibactam | 27/27 (100%) | 27/27 (100%) | 26/27 (96.3%) | 27/27 (100%) | 26/27 (96.3%) | 27/27 (100%) |
| Ceftolozane/Tazobactam | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 26/27 (96.3%) | 26/26 (100%) |
| Ceftriaxone | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) |
| Cefuroxime | 12/15* (80.0%) | 15/15 (100%) | 14/15 (93.3%) | 12/15* (80.0%) | 13/15 (86.7%) | 12/15 (80.0%) |
| ESBL** | 15/15 (100%) | 15/15 (100%) | 14/15 (93.3%) | 15/15 (100%) | 15/15 (100%) | 15/15 (100%) |
K230675 - Page 23 of 47
{23}
| Antimicrobial | Instrument (36°C-37°C) No. EA/Total Tested (EA%) | | | Bench (RT) No. EA/Total Tested (EA%) | | |
| --- | --- | --- | --- | --- | --- | --- |
| | T0 | T8 | T16 | T0 | T8 | T16 |
| Amikacin | 30/30 (100%) | 30/30 (100%) | 27/30 (90.0%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) |
| Aztreonam | 27/30 (90.0%) | 30/30 (100%) | 30/30 (100%) | 27/30 (90.0%) | 30/30 (100%) | 29/29 (100%) |
| Ertapenem | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) |
| Gentamicin | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) |
| Imipenem | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) | 27/27 (100%) |
| Meropenem | 30/30 (100%) | 29/30 (96.7%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) |
| Meropenem/Vaborbactam | 22/24 (91.7%) | 24/24 (100%) | 24/24 (100%) | 22/24 (91.7%) | 24/24 (100%) | 24/24 (100%) |
| Piperacillin/Tazobactam | 30/30 (100%) | 29/30 (96.7%) | 27/30 (90.0%) | 30/30 (100%) | 30/30 (100%) | 27/30 (90.0%) |
| Tobramycin | 29/29 (100%) | 28/30 (93.3%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) | 30/30 (100%) |
| Trimethoprim/ Sulfamethoxazole | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) |
| Amoxicillin/Clavulanate | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) |
| Cefepime | 24/24 (100%) | 23/23 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 23/23 (100%) |
| Ciprofloxacin | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) |
| Levofloxacin | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) | 24/24 (100%) |
| Tetracycline | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) | 12/12 (100%) |
* As described above, comparison to T0 and other timepoints resulted in an EA/CA of 100%.
** Assay is qualitative. Values reported in the table is %CA.
# 6. Detection Limit:
Not applicable
# 7. Assay Cut-Off:
Not applicable
# 8. Accuracy (Instrument):
Not applicable
K230675 - Page 24 of 47
{24}
# 9. Carry-Over:
# **Crosstalk Study:**
The purpose of this study was to assess whether volatile organic compounds (VOC's) emitted by growing bacteria are exchanged between adjacent wells on the same panel during testing with the VITEK REVEAL GN Assay and the VITEK REVEAL AST System. Contrived positive blood cultures containing one of five organisms (*E. coli*, *K. pneumoniae*, *P. aeruginosa*, *P. mirabilis*, and *A. baumannii*) were tested in a checkerboard pattern with media-only. The five organisms were rotated over 20 days to generate 4 replicate plates for each bacterial organism using a different analyzer and sealer each day of testing. VOC's were detected in the media-only wells one time (1) out of 960 wells tested for a contamination rate of 0.1%, which is acceptable.
# **Carryover Study:**
The purpose of this study was to evaluate the potential for organism or VOC carryover between VITEK REVEAL GN Assay panels run on the same VITEK REVEAL AST System. Following the processing of a contrived positive blood culture panel, a media-only panel was processed on the same instrument and sealer. Twenty (20) media only panels were processed and VOC's were detected in one (1) out of 1920 wells tested. This is a contamination rate of less than 0.1%, which is acceptable.
# **B Comparison Studies:**
# 1. Method Comparison with Predicate Device:
Clinical performance testing on the VITEK REVEAL AST System using the VITEK REVEAL GN Assay was performed at five external, geographically diverse, U.S. clinical test sites. The broth microdilution testing was performed at a single reference site. Challenge isolate testing was performed at two internal sites. Performance was evaluated using fresh (prospective) positive blood cultures, as well as positive blood culture samples contrived with clinical stock isolates and challenge isolates. The challenge isolates were selected for their resistance profiles. Positive blood cultures confirmed by Gram stain to contain only Gram-negative rods were enrolled into the study.
Organism identification was obtained from an FDA cleared molecular bacterial identification method and/or FDA cleared MALDI TOF method for input into the VITEK REVEAL AST System. The species identification provided by the clinical site was confirmed at the reference site using an FDA-cleared MALDI identification method. Any samples with a species identification at the reference site not matching the expected ID or found to be polymicrobial did not proceed to BMD testing.
A total of 1,115 positive blood cultures (424 fresh (prospective), 101 seeded with stock organisms, and 590 seeded with challenge organisms) were tested to evaluate the VITEK REVEAL AST System performance for 22 antimicrobials and one screening test, ESBL, using the VITEK REVEAL GN Assay. Depending on the spectrum of activity, breakpoints, and the claimed organisms (species/group) for each antimicrobial on the panel, the number of datapoints for the various antimicrobial-organisms tested varied. VITEK REVEAL results were compared to the modal value of triplicate broth microdilution reference results performed at an independent reference laboratory.
K230675 - Page 25 of 47
{25}
Performance was determined generally based on criteria outlined in the Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems including essential agreement (EA), categorical agreement (CA), and categorical errors (minor, major and very major errors). EA was calculated as the percentage of VITEK REVEAL MIC results that were within plus or minus one serial two-fold dilution of the reference result. CA was calculated as the percentage of VITEK REVEAL interpretive results (S/I/R) that were identical to the interpretive results of the reference result. EA of evaluable results (on-scale VITEK REVEAL and reference results or results in which an off-scale result was at least two doubling dilutions from the on-scale result) were also calculated. Performance was considered acceptable if the EA and CA were ≥90%, major error rate was ≤3%, and very major error rate was ≤2%. For antimicrobials that lack an intermediate interpretive result, further analysis of the category errors was performed, and adjustments were made by considering the MIC values that were one doubling dilution from the reference MIC value.
A high-level summary of the performance of the VITEK REVEAL AST System is described below for each antimicrobial and indicated species. Complete details and results including EA, CA and error rate analyses are summarized below in Tables 9 and 10.
Amikacin. A total of 756 specimens (299 E. coli, 123 K. pneumoniae group, 40 K. oxytoca, 48 K. aerogenes, 39 E. cloacae complex, 23 C. freundii complex, 31 P. mirabilis, 28 S. marcescens, 60 A. baumannii-calcoaceticus complex, and 65 P. aeruginosa) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 98.1% and CA of 99.4%. There were four (4) minor (0.6%), no major and no very major errors. Overall, performance is acceptable.
The A. baumannii-calcoaceticus results from clinical and challenge testing demonstrated an EA of 90% and CA of 88.3%. There were seven (7) minor (11.7%), no major and no very major errors. The low CA was due to seven (7) minor errors with six (6) of the minor errors being in essential agreement. The following statement is included as a limitation in the device labeling to address the minor errors:
For amikacin, perform an alternative method of testing prior to reporting of results for A. baumannii-calcoaceticus complex when the MIC is 32 μg/mL due to the occurrence of minor errors, that were in essential agreement, resulting in a category agreement below 90%.
The P. aeruginosa results from clinical and challenge testing demonstrated an EA of 95.4% and CA of 95.4%. There were three (3) minor (4.6%), no major and no very major errors. Overall, performance is acceptable.
Amoxicillin/Clavulanate. A total of 500 Enterobacterales specimens (302 E. coli, 124 K. pneumoniae group, 41 K. oxytoca, and 33 P. mirabilis) were evaluated. The results from clinical and challenge testing demonstrated an EA of 95% and CA of 90.8%. There were 43 minor (8.6%), 3 major (0.7%) and no very major errors. Overall, performance is acceptable.
When evaluating results by individual species, thirty-five (35) of the minor errors were due to E. coli. The EA was 94.4% and the CA was 88%. There were 35 minor (11.6%), one (1) major (0.4%) and no very major errors. The low CA was due to the 35 minor errors with 29
K230675 - Page 26 of 47
{26}
of the minor errors being in essential agreement. The following statement is included as a limitation in the device labeling to address the minor errors:
For amoxicillin/clavulanate, perform an alternative method of testing prior to reporting of results for *E. coli* when the MIC is 16 µg/mL due to the occurrence of minor errors, that were in essential agreement, resulting in a category agreement below 90%.
**Ampicillin/Sulbactam.** A total of 372 Enterobacterales specimens (300 *E. coli*, 40 *K. oxytoca*, and 32 *P. mirabilis*) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 97.8% and CA of 77.2%. According to the AST Special Controls document, a CA <90.0% caused by a high number of minor errors is acceptable when very good EA of evaluable results are observed. The EA of evaluable results was high at 95.6%. There were 82 minor (22.0%), three (3) major (1.2%) and no very major errors. Overall, performance is acceptable.
To address the low CA, the following statement is included as a footnote to the AST performance table:
The majority of ampicillin/sulbactam CA errors for Enterobacterales were minor errors.
When evaluating results by individual species, sixty-six (66) of the minor errors (22.0%) were due to *E. coli*, which demonstrated an EA of 97.3% and the CA of 77.1%. There were three (3) major (1.5%) and no very major errors. The EA of evaluable results was 94.3%. In addition, fourteen (14) of the minor errors (35.0%) were due to *K. oxytoca*. There were no major and no very major errors. The EA is 100% and the CA is 65% with an EA of evaluable isolates at 100%. There were no major and no very major errors. According to the AST Special Controls document, a CA <90.0% caused by a high number of minor errors is acceptable when very good EA of evaluable results are observed; therefore, performance for *E. coli* and *K. oxytoca* is acceptable.
**Aztreonam.** A total of 595 specimens (295 *E. coli*, 127 *K. pneumoniae* group, 43 *K. oxytoca*, 39 *E. cloacae* complex, 26 *C. freundii* complex and 65 *P. aeruginosa*) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 97.4% and CA of 96.0%. There were 18 minor (3.4%), 3 major (0.8%) and no very major errors. Overall, performance is acceptable.
The *P. aeruginosa* results from clinical and challenge testing demonstrated an EA of 96.9% and CA of 86.2%. According to the AST Special Controls document, a CA <90.0% caused by a high number of minor errors is acceptable when very good EA of evaluable results are observed. The EA of evaluable results was high at 96.1%, which is acceptable. There were nine (9) minor (13.8%), no major and no very major errors. Overall, performance is acceptable.
To address the low CA, the following statement is included as a footnote to the AST performance table:
All aztreonam CA errors for *P. aeruginosa* were minor errors.
**Cefepime.** A total of 645 specimens (301 *E. coli*, 121 *K. pneumoniae* group, 40 *K. oxytoca*, 46 *K. aerogenes*, 35 *E. cloacae* complex, 36 *C. koseri* and 66 *P. aeruginosa*) were evaluated.
K230675 - Page 27 of 47
{27}
The Enterobacterales results from clinical and challenge testing demonstrated an EA of 96.0% and CA of 95.9%. There were 21 minor (3.6%), 3 major (0.7%) and no very major errors. Overall, performance is acceptable.
When evaluating results by individual species, E. cloacae complex results from clinical and challenge testing demonstrated an EA of 97.2% and CA of 88.9%. There were four (4) minor (11.4%), no major and no very major errors. According to the AST Special Controls document, a CA <90.0% caused by a high number of minor errors is acceptable when very good EA of evaluable results are observed. The EA of evaluable results was high at 94.4%, which is acceptable.
The P. aeruginosa results from clinical and challenge testing demonstrated an EA of 97.0% and CA of 97.0%. There were two (2) major (6.1%) errors and no very major errors. The two major errors had an MIC value that was in essential agreement with the reference MIC. Therefore, due to the lack of an intermediate interpretive criterion, the adjusted major error rate was 0%, which is acceptable. Overall, performance is acceptable.
Cefotaxime. A total of 592 specimens (303 E. coli, 123 K. pneumoniae group, 42 K. oxytoca, 47 K. aerogenes, 39 E. cloacae complex, and 38 A. baumannii-calcoaceticus) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 97.3% and CA of 99.1%. There were three (3) minor (0.5%), two (2) major (0.5%) and no very major errors. Overall, performance is acceptable.
The A. baumannii-calcoaceticus results from clinical and challenge testing demonstrated an EA of 100% and CA of 100%. There were no minor, no major errors, and no very major errors. Overall, performance is acceptable. The following statement is included as a footnote to the AST performance table to address the lack of testing susceptible isolates:
No cefotaxime susceptible strains were evaluated for A. baumannii-calcoaceticus complex. Cefotaxime susceptibility is rare in A. baumannii-calcoaceticus complex.
Ceftazidime. A total of 619 specimens (302 E. coli, 123 K. pneumoniae group, 40 K. oxytoca, 47 K. aerogenes, 38 E. cloacae complex, 30 C. koseri and 39 A. baumannii-calcoaceticus) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 95.3% and CA of 97.1%. There were 16 minor (2.8%), one (1) major (0.2%) and no very major errors. Overall, performance is acceptable.
The A. baumannii-calcoaceticus results from clinical and challenge testing demonstrated an EA of 97.4% and CA of 94.9%. There were two (2) minor (5.1%), no major errors and no very major errors. Overall, performance is acceptable.
Ceftazidime/Avibactam. A total of 717 clinical specimens (301 E. coli, 124 K. pneumoniae group, 67 K. aerogenes, 39 E. cloacae complex, 24 C. freundii complex, 30 C. koseri, 39 P. mirabilis and 93 P. aeruginosa) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 95.7% and CA of 99.7%. There were one (1) major (0.2%) error and one (1) very major (1.9%) error. Overall, performance is acceptable.
When evaluating results by individual species, K. aerogenes demonstrated an EA of 91.0% and CA of 98.5%. There were no major errors and one (1) very major (33.3%) error. The one
K230675 - Page 28 of 47
{28}
(1) very major error had an MIC value that was in essential agreement with the reference MIC. Therefore, due to the lack of an intermediate interpretive criterion, the adjusted very major error rate was 0%, which is acceptable. Overall, performance is acceptable.
The *P. aeruginosa* results from clinical and challenge testing demonstrated an EA of 97.8% and CA of 97.8%. There were no minor, two (2) major (3%) errors and no very major errors. Overall, performance is acceptable.
**Ceftolozane/Tazobactam.** A total of 576 specimens (293 *E. coli*, 40 *K. oxytoca*, 45 *K. aerogenes*, 37 *E. cloacae complex*, 42 *C. koseri*, 31 *P. mirabilis*, 22 *P. vulgaris* and 66 *P. aeruginosa*) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 92.9% and CA of 97.6%, which is acceptable. There were 10 minor errors (2.0%), one (1) major (0.2%) error and one (1) very major (1.5%) error. Overall, performance is acceptable.
When evaluating results by individual species, for *K. aerogenes* the EA was 93.3% and CA was 88.9%. There were five (5) minor (11.0%), no major and no very major errors. According to the AST Special Controls document, a CA <90.0% caused by a high number of minor errors is acceptable when very good EA of evaluable results are observed. The EA of evaluable results was 92.3%, which is acceptable.
For *K. oxytoca*, the EA was 95% and the CA was 97.5%. There were no minor, no major and one (1) very major (33%) error. The one (1) very major error was considered a random error due to the limited number of resistant isolates tested. This performance is acceptable.
For *P. aeruginosa* the results from clinical and challenge testing demonstrated an EA of 100% and CA of 98.5%. There were one (1) minor (1.5%), no major and no very major errors. Overall, performance is acceptable.
**Ceftriaxone.** A total of 626 specimens (294 *E. coli*, 132 *K. pneumoniae* group, 47 *K. oxytoca*, 52 *K. aerogenes*, 46 *E. cloacae* complex, and 55 *P. mirabilis*) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 97.1% and CA of 96.6%. There were 18 minor (2.9%), three (3) major (0.7%) and no very major errors. Overall, performance is acceptable.
**Cefuroxime.** A total of 522 specimens (300 *E. coli*, 119 *K. pneumoniae* group, 40 *K. oxytoca*, 27 *C. koseri*, and 36 *P. mirabilis*) were evaluated. The Enterobacterales results from clinical and challenge testing demonstrated an EA of 95.8% and CA of 97.3%. There were no minor, 13 major (3.5%) errors and one (1) very major (0.7%) error. Four (4) major errors had an MIC value that was in essential agreement with the reference MIC. Therefore, due to the lack of an intermediate interpretive criterion, the adjusted major error rate was 2.4%. Overall, performance is acceptable.
When evaluating results by individual species, for *K. pneumoniae* group, the EA was 97.4% and the CA was 100%. There were no minor, five (5) major (7.1%) and no very major errors. The following statement is included as a limitation in the device labeling to address the major errors:
K230675 - Page 29 of 47
{29}
Due to the occurrence of a major errors with cefuroxime, isolates of K. pneumoniae group that provide a MIC of 16 μg/mL should be retested by an alternate method.
For K. oxytoca, the EA was 97.5% and the CA was 90%. There were no minor, four (4) major (14.8%) errors and no very major errors. The following statement is included as a limitation in the device labeling to address the major errors:
Due to the occurrence of a major errors with cefuroxime, isolates of K. oxytoca that provide a MIC of 32 μg/mL should be retested by an alternate method.
For C. koseri, the EA was 92.6% and the CA was 96.3%. There were no minor, one (1) major (4.3%) error and…
