ASTar BC G- Kit and ASTar Instrument

• K Number: K221688
• Device Name: ASTar BC G- Kit and ASTar Instrument
• Manufacturer: Q-linea AB
• Date Cleared: 2024-04-26 ( 686 days)
• Product Code: SAN LON
• Regulation Number: 866.1650

Intended Use

Intended Use: The ASTar System is intended to be used for the automated quantitative susceptibility testing for most clinically significant microorganisms. The ASTar System does not provide organism identification. Indications for Use: The ASTar System, comprised of the ASTar Instrument with the ASTar BC G- Kit (ASTar BC G- Consumable kit, ASTar BC G- Frozen insert, and ASTar BC G-Kit software), utilizes high-speed, time-lapse microscopy imaging of bacteria for the in vitro, quantitative determination of antimicrobial susceptibility of on-panel gram-negative bacteria. The test is performed directly on positive blood culture samples signaled as positive by a continuous monitoring blood culture system and confirmed to contain gram-negative bacilli by Gram stain. Organism identification is required for AST result interpretation and reporting. Test results from the ASTar BC G- Kit 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 ASTar BC G- panel, where inconclusive results are obtained, epidemiologic testing, recovery of organisms present in microbial samples, and susceptibility testing of bacteria in polymicrobial samples. The ASTar BC G- Kit tests the following antimicrobial agents with the following bacterial species: Amikacin: Citrobacter freundii, Enterobacter cloacae complex, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens Ampicillin: Escherichia coli, Proteus mirabilis Ampicillin-sulbactam: Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris Aztreonam: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens Cefazolin: Klebsiella pneumoniae Cefepime: Citrobacter freundii, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens Ceftazidime: Enterobacter cloacae complex, Escherichia oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens Ceftazidime-avibactam: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Klebsiella oxytoca, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens Cefuroxime: Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis Ciprofloxacin: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens Gentamicin: Citrobacter freundii, Citrobacter koseri, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens Levofloxacin: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens Meropenem: Acinetobacter baumannii, Citrobacter freundii, Citrobacter koseri, Escherichia coli, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens Meropenem-vaborbactam: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens Piperacillin-tazobactam: Citrobacter koseri, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens Tigecycline: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Serratia marcescens Tobramycin: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens Trimethoprim-sulfamethoxazole: Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus vulgaris

Device Description

ASTar System is a fully automated system for antimicrobial susceptibility testing (AST). It consists of the ASTar Instrument which is used in combination with dedicated application kits. The ASTar BC G- Kit consists of the ASTar BC G- Consumable kit, ASTar BC G- Frozen insert, and ASTar BC G-Kit software which must be installed on the instrument to process the kit. The system provides robust and consistent inoculum preparation for AST and utilizes high-speed, time-lapse microscopy imaging of pathogens in broth microdilution to determine minimum inhibitory concentration (MIC) and qualitative susceptibility results. Organism identification using an approved method is required to be entered into the ASTar Instrument for results to be reported. The instrument is designed to carry out sample preparation of up to six samples in parallel, using a dedicated ASTar Cartridge consumable for each sample. In the subsequent AST culturing step, the instrument transfers the prepared sample into a second dedicated consumable, referred to as the ASTar Disc. Up to 12 Discs can be incubated simultaneously in the system. The processed samples can be in different stages of the processing protocol. New samples can be loaded in a random-access manner when there are available slots. Processing of loaded samples will, in most cases, start shortly after loading. If six samples are started at the same time limitations given by the sample scheduler will result in a queue. The operator interacts with the instrument via the touchscreen display by which the operator controls the instrument. ASTar BC G- Kit is used for in vitro determination of antimicrobial susceptibility testing of commonly isolated bacteria derived from positive blood culture samples confirmed positive for Gram-negative bacteria by Gram stain. The antimicrobial and organism combinations are listed in Table 1. Reportable ranges for each antimicrobial are listed in Table 2. To start an analysis approximately 1 mL of a positive blood culture, confirmed Gram-negative by Gram stain is pipetted into the ASTar Cartridge by the operator and loaded into the system, from which the system purifies and quantifies the bacterial concentration is adjusted to the appropriate inoculum concentration and produces an inoculum for analysis of non-fastidious organisms. The bacterial suspensions are transferred automatically to the ASTar Disc and antimicrobial susceptibility testing is performed based on a defined short-term protocol. Results are available within approximately six hours. Bacterial growth and response to relevant concentrations of different antimicrobial drugs are measured throughout the incubation period, using a high-performance optical detection system in combination with image analysis algorithms. The system generates an MIC and further qualitative susceptibility results (i.e., S, I, R) for the tested antimicrobials when applicable. The qualitative results are determined based on established breakpoints stipulated by applicable authorities, i.e., FDA, CLSI or EUCAST. FDA Susceptibility Testing Interpretive Criteria (STIC), aka "breakpoints" are found in Table 3.

Predicate Devices

DEN160032

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The document mentions "image analysis algorithms" but does not explicitly state or imply the use of AI or ML for these algorithms or any other part of the system.

Therapeutic

No
The device is an in vitro diagnostic (IVD) system used for automated quantitative antimicrobial susceptibility testing, which provides information for clinicians to determine treatment, but does not directly deliver therapy or perform a therapeutic function.

Diagnostic

Yes

The ASTar System is intended for the automated quantitative susceptibility testing for clinically significant microorganisms, which is a diagnostic purpose to determine how effective antimicrobial agents are against specific bacterial species. It provides quantifiable results (MIC) and qualitative susceptibility results (S, I, R) that are used in conjunction with other clinical and laboratory findings to aid in patient treatment decisions.

SaMD (Software as a Medical Device)

No

The device is described as a "fully automated system" consisting of an "ASTar Instrument" used in combination with "dedicated application kits" and consumables (Cartridge, Disc). While it includes "ASTar BC G-Kit software," the system clearly involves significant hardware components for sample preparation, incubation, and high-speed, time-lapse microscopy imaging.

IVD (In Vitro Diagnostic)

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

Here's why:

• Intended Use: The Intended Use statement explicitly states that the ASTar System is intended for "in vitro, quantitative determination of antimicrobial susceptibility". The term "in vitro" is a key indicator of an IVD.
• Indications for Use: The Indications for Use further clarifies that the test is performed "in vitro" on positive blood culture samples.
• Device Description: The Device Description mentions that the ASTar BC G- Kit is used for "in vitro determination of antimicrobial susceptibility testing".
• Clinical Study: The description of the clinical study confirms that the device is used to test patient samples (positive blood cultures) to provide results for clinical interpretation.

All of these points align with the definition of an In Vitro Diagnostic device, which is a medical device intended for use in vitro for the examination of specimens derived from the human body solely or principally for the purpose of providing information concerning a physiological or pathological state, or concerning a congenital abnormality, or to monitor therapeutic measures.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

Intended Use: The ASTar System is intended to be used for the automated quantitative susceptibility testing for most clinically significant microorganisms. The ASTar System does not provide organism identification.

Indications for Use: The ASTar System, comprised of the ASTar Instrument with the ASTar BC G- Consumable kit, ASTar BC G-Frozen insert, and ASTar BC G-Kit software), utilizes high-speed, time-lapse microscopy imaging of bacteria for the in vitro, quantitative determination of antimicrobial susceptibility of on-panel gram-negative bacteria. The test is performed directly on positive blood culture samples signaled as positive by a continuous monitoring blood culture system and confirmed to contain gram-negative bacilli by Gram stain. Organism identification is required for AST result interpretation and reporting.

Test results from the ASTar BC G-Kit 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 ASTar BC G- panel, where inconclusive results are obtained, epidemiologic testing, recovery of organisms present in microbial samples, and susceptibility testing of bacteria in polymicrobial samples.

The ASTar BC G- Kit tests the following antimicrobial agents with the following bacterial species:

Amikacin: Citrobacter freundii, Enterobacter cloacae complex, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Ampicillin: Escherichia coli, Proteus mirabilis

Ampicillin-sulbactam: Escherichia coli, Klebsiella oxytoca. Klebsiella pneumoniae. Proteus vulgaris

Aztreonam: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Cefazolin: Klebsiella pneumoniae

Cefepime: Citrobacter freundii, Escherichia coli, Klebsiella oxytoca, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Ceftazidime: Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca. Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Ceftazidime-avibactam: Citrobacter freundii, Citrobacter cloacae complex, Klebsiella oxytoca, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Cefuroxime: Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis

Ciprofloxacin: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Gentamicin: Citrobacter freundii, Citrobacter koseri, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Levofloxacin: Citrobacter freundii, Citrobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aerueinosa, Serratia marcescens

Meropenem: Acinetobacter baumanii, Citrobacter freundii, Citrobacter koseri, Escherichia coli, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Meropenem-vaborbactam: Citrobacter freundii, Citrobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens

Piperacillin-tazobactam: Citrobacter koseri, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Serratia marcescens

Tigecycline: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Serratia marcescens

Tobramycin: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens

Trimethoprim-sulfamethoxazole: Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus vulgaris

Product codes

SAN, LON

Device Description

ASTar System is a fully automated system for antimicrobial susceptibility testing (AST). It consists of the ASTar Instrument which is used in combination with dedicated application kits. The ASTar BC G- Kit consists of the ASTar BC G- Consumable kit, ASTar BC G- Frozen insert, and ASTar BC G-Kit software which must be installed on the instrument to process the kit.

The system provides robust and consistent inoculum preparation for AST and utilizes high-speed, time-lapse microscopy imaging of pathogens in broth microdilution to determine minimum inhibitory concentration (MIC) and qualitative susceptibility results. Organism identification using an approved method is required to be entered into the ASTar Instrument for results to be reported.

The instrument is designed to carry out sample preparation of up to six samples in parallel, using a dedicated ASTar Cartridge consumable for each sample. In the subsequent AST culturing step, the instrument transfers the prepared sample into a second dedicated consumable, referred to as the ASTar Disc. Up to 12 Discs can be incubated simultaneously in the system. The processed samples can be in different stages of the processing protocol. New samples can be loaded in a random-access manner when there are available slots. Processing of loaded samples will, in most cases, start shortly after loading. If six samples are started at the same time limitations given by the sample scheduler will result in a queue. The operator interacts with the instrument via the touchscreen display by which the operator controls the instrument.

ASTar BC G- Kit is used for in vitro determination of antimicrobial susceptibility testing of commonly isolated bacteria derived from positive blood culture samples confirmed positive for Gram-negative bacteria by Gram stain. The antimicrobial and organism combinations are listed in Table 1. Reportable ranges for each antimicrobial are listed in Table 2.

To start an analysis approximately 1 mL of a positive blood culture, confirmed Gram-negative by Gram stain is pipetted into the ASTar Cartridge by the operator and loaded into the system, from which the system purifies and quantifies the bacterial concentration is adjusted to the appropriate inoculum concentration and produces an inoculum for analysis of non-fastidious organisms. The bacterial suspensions are transferred automatically to the ASTar Disc and antimicrobial susceptibility testing is performed based on a defined short-term protocol. Results are available within approximately six hours. Bacterial growth and response to relevant concentrations of different antimicrobial drugs are measured throughout the incubation period, using a high-performance optical detection system in combination with image analysis algorithms. The system generates an MIC and further qualitative susceptibility results (i.e., S, I, R) for the tested antimicrobials when applicable. The qualitative results are determined based on established breakpoints stipulated by applicable authorities, i.e., FDA, CLSI or EUCAST. FDA Susceptibility Testing Interpretive Criteria (STIC), aka "breakpoints" are found in Table 3.

Mentions image processing

Yes

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

high-speed, time-lapse microscopy imaging

Anatomical Site

Not Found

Indicated Patient Age Range

Not Found

Intended User / Care Setting

Not Found

Description of the training set, sample size, data source, and annotation protocol

Not Found

Description of the test set, sample size, data source, and annotation protocol

A total of 1,068 samples were enrolled in the study, across Fresh PBC (positive blood cultures) and contrived positive blood culture with either clinical stock or challenge isolates. 188 samples were excluded due to off-panel organisms, contamination of contrived samples either due to the blood used for contriving or other sources, non-viable stock isolates, and protocol deviations. In total 880 samples were included in the performance analysis including 256 fresh, positive blood cultures, 223 contrived with clinical stock isolates and 401 contrived blood cultures with challenge isolates.

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

Reproducibility: A reproducibility study was conducted with 23 bacterial strains to obtain at least six on-scale MIC values for each antimicrobial. Triplicate samples from each contrived blood culture were tested at three separate sites on at least two separate days (supplementary testing was conducted in-house with three individual instruments). In total, all samples were tested within 16 hours of bottle positivity. The system demonstrated an overall reproducibility of ≥ 95% based on the number of results that fall within ±1 doubling dilution between the test MIC result and test MIC mode for best-case scenario calculations. For worst-case scenario calculations, all antimicrobials showed reproducibility above 89% except for Ceftazidime-avibactam at 88.8%, and Ceftazidime at 88%.

Blood Culture Bottle Compatibility: Ten (10) isolates were included in the study. All ten (10) isolates were run in triplicates in the six aerobic bottles. Eight (8) isolates, excluding A. baumannii and P. aeruginosa, were run in triplicate in the five anaerobic bottles. All bottle types had an MIC value within ±1 doubling dilution to the mode across all bottle types in >95% of all MICs evaluated, indicating similar performance.

Sample Stability: Samples were tested within different timeframes after BCB positivity for each time/incubation condition. The study included nine (9) isolates, from E. coli, K. oxytoca, K. pneumoniae, P. aeruginosa, P. mirabilis, E. cloacae, S. marcescens, C. koseri and A. baumannii. All timepoints were tested in triplicate with all organisms. Samples stored for up to 16 hours after positivity at either room temperature or at 35 °C in a blood culture cabinet produced equivalent results to samples loaded into the ASTar System within 1-hour of positivity. Pass/fail criteria were >95% of MIC values within ±1 doubling dilution of the mode MIC of initial samples (loaded 95% pass rate as compared to control samples without interfering antibiotics.

Carry Over and Cross Contamination: Evaluated using two different E. coli isolates (susceptible and resistant) run in an alternating fashion, followed by susceptible isolate samples as controls. 14 susceptible samples were evaluated. No carry over or cross contamination was observed as evidenced by 99.7% pass rate (307/308).

Set Inoculum for AST: A study was performed to assess the accuracy of the ASTar System to measure and adjust bacterial concentration. Contrived positive BCB from four different species of bacteria (E. coli, P. aeruginosa, E. cloacae and K. aerogenes) were evaluated across a 6-logarithmic dilution range in triplicate. For positive BCB and dilutions with a starting bacterial concentration >5 x 10^7 CFU/mL, the concentration was assessed and adjusted successfully by the ASTar System for 95.8% (23/24) of samples and 100% of those (23/23), produced an inoculum within the acceptance ranges for AST.

Clinical Study: The purpose was to demonstrate clinical performance for quantitative AST results direct from positive blood culture containing Gram-negative bacteria, compared to reference frozen Broth Micro-Dilution (BMD) results. Data was generated from two testing periods, initial and supplemental, at three external clinical sites in the US and one internal site in Sweden. A total of 933 valid samples were analyzed on the ASTar during the clinical study and 97.2% (907/933) of samples produced at least a partial AST result. Of the 26 samples that failed to produce an AST result, 96% (25/26) were resolved upon retesting. AST performance was generally high across most antimicrobials for Essential Agreement (EA), Category Agreement (CA), Very Major (VMJ) rates and Major (MAJ) rates.

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

Reproducibility: Overall reproducibility of ≥ 95% based on MIC values within ±1 doubling dilution from the test MIC mode.
Blood Culture Bottle Compatibility: Overall essential agreement (EA) compared to reference MIC obtained by frozen broth microdilution according to CLSI M07 shall be ≥90% for each antimicrobial, stratified by bacteria. MIC values within ±1 doubling dilution of the mode MIC for each antimicrobial/bottle were determined.
Sample Stability: Pass/fail criteria were >95% of MIC values within ±1 doubling dilution of the mode MIC of initial samples.
Interfering Substances: Pass rate of 100% for most categories, 99.1% for RBCs.
Interfering Antibiotics: Acceptance criteria of >95% pass rate.
Carry Over and Cross Contamination: 99.7% pass rate (307/308).
Set Inoculum for AST: 95.8% of samples with >5 x 10^7 CFU/mL starting concentration had successful adjustment; 100% of those produced an inoculum within acceptance ranges.

Clinical Study - Table 16: Overall AST performance of antimicrobials.

Antimicrobial	Group	Assessed	No. EA	EA %	Eval EA Tot	No. Eval EA	Eval EA %	No. CA	CA %	No. R	No. S	MIN	MAJ	VMJ
Amikacin	Enterobacterales	460	436	94.78	442	418	94.57	455	98.91	4	447	5	0	0
Amikacin	Pseudomonas aeruginosa	64	59	92.19	62	57	91.94	62	96.88	2	59	2	0	0
Ampicillin	Enterobacterales	236	230	97.46	106	100	94.34	231	97.88	115	121	3	2	0
Ampicillin-sulbactam	Enterobacterales	445	434	97.53	348	338	97.13	399	89.66	138	252	45	1	0
Aztreonam	Enterobacterales	637	615	96.55	124	102	82.26	617	96.86	150	473	16	0	4
Cefazolin	Klebsiella pneumoniae	140	135	96.43	77	72	93.51	123	87.86	69	63	15	1	1
Cefepime	Enterobacterales	632	601	95.09	125	94	75.2	608	96.2	107	503	22	2	0
Cefepime	Pseudomonas aeruginosa	64	60	93.75	58	54	93.1	57	89.06	22	42	0	3	4
Ceftazidime	Enterobacterales	549	491	89.44	208	150	72.12	531	96.72	143	394	14	2	2
Ceftazidime-avibactam	Enterobacterales	229	212	92.58	109	92	84.4	227	99.13	7	222	0	1	1
Ceftazidime-avibactam	Pseudomonas aeruginosa	28	28	100	28	28	100	28	100	1	27	0	0	0
Cefuroxime	Enterobacterales	427	403	94.38	280	256	91.43	412	96.49	142	285	0	12	3
Ciprofloxacin	Enterobacterales	693	676	97.55	87	70	80.46	667	96.25	155	521	18	6	2
Ciprofloxacin	Pseudomonas aeruginosa	28	27	96.43	12	11	91.67	23	82.14	3	21	5	0	0
Gentamicin	Enterobacterales	381	363	95.28	320	302	94.38	370	97.11	29	347	10	1	0
Gentamicin	Pseudomonas aeruginosa	64	60	93.75	60	56	93.33	62	96.88	8	54	2	0	0
Levofloxacin	Enterobacterales	683	671	98.24	160	148	92.5	649	95.02	131	531	29	3	2
Levofloxacin	Pseudomonas aeruginosa	28	26	92.86	26	24	92.31	23	82.14	3	21	5	0	0
Meropenem	Acinetobacter baumannii	46	44	95.65	40	38	95	43	93.48	19	25	3	0	0
Meropenem	Enterobacterales	340	307	90.29	59	26	44.07	334	98.24	10	328	3	0	3
Meropenem	Pseudomonas aeruginosa	24	22	91.67	23	21	91.3	24	100	1	22	0	0	0
Meropenem-vaborbactam	Enterobacterales	663	643	96.98	41	21	51.22	656	98.94	7	652	7	0	0
Piperacillin-tazobactam	Enterobacterales	494	461	93.32	398	365	91.71	466	94.33	84	396	20	5	3
Tigecycline	Enterobacterales	629	604	96.03	629	604	96.03	613	97.46	7	608	14	0	2
Tobramycin	Enterobacterales	354	328	92.66	347	321	92.51	327	92.37	48	289	24	1	2
Trimethoprim-sulfamethoxazole	Enterobacterales	542	520	95.94	193	171	88.6	536	98.89	133	409	0	5	1

Predicate Device(s)

Accelerate PhenoTest BC Kit. DEN160032

Reference Device(s)

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information

Not Found

Regulation Number and Section

§ 866.1650 A cellular analysis system for multiplexed antimicrobial susceptibility testing.

(a)
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.(b)
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.

Summary

0

Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.

April 26, 2024

Q-linea AB % Peter Trabold Regulatory Affairs Specialist MDC Associates, Inc. 48 Dunham Ridge Road Suite 4000 Beverly, Massachusetts 01915

Re: K221688

Trade/Device Name: ASTar BC G- Kit and ASTar Instrument Regulation Number: 21 CFR 866.1650 Regulation Name: A Cellular Analysis System For Multiplexed Antimicrobial Susceptibility Testing Regulatory Class: Class II Product Code: SAN, LON Dated: November 15, 2023 Received: November 15, 2023

Dear Peter Trabold:

We have reviewed your section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (the Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

1

Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review. the OS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safetyreporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

Sincerely,

Natasha Griffin -S

o.b.o. Ribhi Shawar, Ph.D. (ABMM) Branch Chief General Bacteriology and Antimicrobial Susceptibility Branch Division of Microbiology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health

2

Indications for Use

510(k) Number (if known) K221688

Device Name ASTar BC G- Kit and ASTar Instrument

Indications for Use (Describe)

Intended Use:

The ASTar System is intended to be used for the automated quantitative susceptibility testing for most clinically significant microorganisms. The ASTar System does not provide organism identification.

Indications for Use:

The ASTar System, comprised of the ASTar Instrument with the ASTar BC G- Consumable kit, ASTar BC G-Frozen insert, and ASTar BC G-Kit software), utilizes high-speed, time-lapse microscopy imaging of bacteria for the in vitro, quantitative determination of antimicrobial susceptibility of on-panel gram-negative bacteria. The test is performed directly on positive blood culture samples signaled as positive by a continuous monitoring blood culture system and confirmed to contain gram-negative bacilli by Gram stain. Organism identification is required for AST result interpretation and reporting.

Test results from the ASTar BC G-Kit 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 ASTar BC G- panel, where inconclusive results are obtained, epidemiologic testing, recovery of organisms present in microbial samples, and susceptibility testing of bacteria in polymicrobial samples.

The ASTar BC G- Kit tests the following antimicrobial agents with the following bacterial species:

Amikacin: Citrobacter freundii, Enterobacter cloacae complex, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Ampicillin: Escherichia coli, Proteus mirabilis

Ampicillin-sulbactam: Escherichia coli, Klebsiella oxytoca. Klebsiella pneumoniae. Proteus vulgaris

Aztreonam: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Cefazolin: Klebsiella pneumoniae

Cefepime: Citrobacter freundii, Escherichia coli, Klebsiella oxytoca, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Ceftazidime: Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca. Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Ceftazidime-avibactam: Citrobacter freundii, Citrobacter cloacae complex, Klebsiella oxytoca, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Cefuroxime: Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis

3

Ciprofloxacin: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Gentamicin: Citrobacter freundii, Citrobacter koseri, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Levofloxacin: Citrobacter freundii, Citrobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aerueinosa, Serratia marcescens

Meropenem: Acinetobacter baumanii, Citrobacter freundii, Citrobacter koseri, Escherichia coli, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Meropenem-vaborbactam: Citrobacter freundii, Citrobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens

Piperacillin-tazobactam: Citrobacter koseri, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Serratia marcescens

Tigecycline: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Serratia marcescens

Tobramycin: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens

Trimethoprim-sulfamethoxazole: Enterobacter cloacae complex, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus vulgaris

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

X Prescription Use (Part 21 CFR 801 Subpart D)

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

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4

8.0 510(k) Summary

Date of Submission: April 8th, 2024

• Sponsor: Q-linea Dag Hammarskjolds vag 52A Uppsala, Sweden 752 37
• Correspondent: MDC Associates, Inc. Peter Trabold, Ph.D., MBA 48 Dunham Ridge Road, Suite 4000 Beverly, MA 01915 Phone: [phone]

8.1 Device

Name of Device:	ASTar® BC G- Kit and ASTar® Instrument
Common Name:	ASTar BC G- Kit and ASTar Instrument
Regulation Number:	21 CRF 866.1650
Classification Name:	A cellular analysis system for multiplexed antimicrobial susceptibility
testing
Regulatory Class:	Class II
Product Code:	SAN, LON
Predicate Device:	Accelerate PhenoTest BC Kit. DEN160032

8.2 Device Description

ASTar System is a fully automated system for antimicrobial susceptibility testing (AST). It consists of the ASTar Instrument which is used in combination with dedicated application kits. The ASTar

5

BC G- Kit consists of the ASTar BC G- Consumable kit, ASTar BC G- Frozen insert, and ASTar BC G-Kit software which must be installed on the instrument to process the kit.

The system provides robust and consistent inoculum preparation for AST and utilizes high-speed, time-lapse microscopy imaging of pathogens in broth microdilution to determine minimum inhibitory concentration (MIC) and qualitative susceptibility results. Organism identification using an approved method is required to be entered into the ASTar Instrument for results to be reported.

The instrument is designed to carry out sample preparation of up to six samples in parallel, using a dedicated ASTar Cartridge consumable for each sample. In the subsequent AST culturing step, the instrument transfers the prepared sample into a second dedicated consumable, referred to as the ASTar Disc. Up to 12 Discs can be incubated simultaneously in the system. The processed samples can be in different stages of the processing protocol. New samples can be loaded in a random-access manner when there are available slots. Processing of loaded samples will, in most cases, start shortly after loading. If six samples are started at the same time limitations given by the sample scheduler will result in a queue. The operator interacts with the instrument via the touchscreen display by which the operator controls the instrument.

ASTar BC G- Kit is used for in vitro determination of antimicrobial susceptibility testing of commonly isolated bacteria derived from positive blood culture samples confirmed positive for Gram-negative bacteria by Gram stain. The antimicrobial and organism combinations are listed in Table 1. Reportable ranges for each antimicrobial are listed in Table 2.

To start an analysis approximately 1 mL of a positive blood culture, confirmed Gram-negative by Gram stain is pipetted into the ASTar Cartridge by the operator and loaded into the system, from which the system purifies and quantifies the bacterial concentration is adjusted to the appropriate inoculum concentration and produces an inoculum for analysis of non-fastidious organisms. The bacterial suspensions are transferred automatically to the ASTar Disc and antimicrobial susceptibility testing is performed based on a defined short-term protocol. Results are available within approximately six hours. Bacterial growth and response to relevant concentrations of different antimicrobial drugs are measured throughout the incubation period, using a high-performance optical detection system in combination with image analysis algorithms. The system generates an MIC and further qualitative susceptibility results (i.e., S, I, R) for the tested antimicrobials when applicable. The qualitative results are determined based on established breakpoints stipulated by applicable authorities, i.e., FDA, CLSI or EUCAST. FDA Susceptibility Testing Interpretive Criteria (STIC), aka "breakpoints" are found in Table 3.

6

Table 1: ASTar BC G- Kit Product Panel

Antimicrobial class	Antimicrobial agent	A. baumannii	C. freundii	C. koseri	E. cloacae complex*	E. coli	K. aerogenes	K. oxytoca	K. pneumoniae	P. aeruginosa	P. mirabilis	P. vulgaris	S. marcescens
Penicillins	Ampicillin					●
β-lactam combination agents	Ampicillin-sulbactam					●		●	●		●	●
β-lactam combination agents	Ceftazidime-avibactam		●	●	●			●		●	●		●
β-lactam combination agents	Meropenem-vaborbactam		●	●	●	●	●	●	●		●		●
β-lactam combination agents	Piperacillin-tazobactam			●		●			●		●	●	●
Cephalosporin	Cefazolin								●
Cephalosporin	Cefepime		●			●	●	●	●	●	●	●	●
Cephalosporin	Cefuroxime					●		●	●		●
Cephalosporin	Ceftazidime				●	●		●	●		●	●	●
Monobactam	Aztreonam			●	●	●	●	●	●
Carbapenem	Meropenem	●	●	●		●				●	●	●	●
Aminoglycoside	Gentamicin		●	●				●	●	●	●	●	●
Aminoglycoside	Tobramycin		●	●	●	●			●		●		●
Aminoglycoside	Amikacin		●		●		●	●	●	●	●		●
Tetracycline	Tigecycline		●	●	●	●	●	●	●
Fluoroquinolone	Ciprofloxacin			●	●	●	●	●	●	●	●	●
Fluoroquinolone	Levofloxacin		●	●	●	●	●	●	●	●	●	●	●
Miscellaneous	Trimethoprim-sulfamethoxazole			●	●	●	●	●			●

• Enterobacter cloacae complex includes E. cloacae, E. asburiae and E. hormaechei.

7

	Table 2: Organisms Antimicrobial Reportable Ranges for AST and QC, Quality Control Strains and
	Acceptable Results. All concentrations are in µg/mL.

| Antimicrobial | ASTar BC G-
Reportable
Range
(AST)5 | ASTar BC G-
Reportable
Range
(QC) | E. coli
ATCC
25922 | P.
aeruginosa
ATCC 27853 | K.
pneumoniae
ATCC
700603 | K.
pneumoniae
ATCC BAA
2814 |
|-----------------------------------|----------------------------------------------|--------------------------------------------|---------------------------------|----------------------------------------------|--------------------------------------------------|----------------------------------------------------|
| Ampicillin | ≤1 to ≥128 | ≤0.5 to ≥128 | 2-8 | | >1284 | |
| Ampicillin-sulbactam | ≤1 to ≥1283 | ≤1 to ≥128 | 2-8 | | 8-32 | |
| Ceftazidime-avibactam | ≤0.125 to ≥64 | ≤0.06 to ≥64 | | 0.5-4 | 0.25-2 | |
| Meropenem-vaborbactam | ≤0.25 to ≥64 | ≤0.06 to ≥64 | | 0.125-1 | | 0.125-0.5 |
| Piperacillin-tazobactam | ≤0.25 to ≥512 | ≤0.125 to ≥5121
≤0.25 to ≥5122 | | 1-8 | 8-32 | |
| Cefazolin | ≤0.25 to ≥32 | ≤0.125 to ≥32 | 1-4 | | | |
| Cefepime | ≤0.25 to ≥128 | ≤0.125 to ≥128 | | 0.5-4 | | |
| Cefuroxime | 256 µg/mL to ≤0.25 - ≥128 µg/mL; Ceftazidime/Escherichia coli: ≤0.03 - ≥256 µg/mL to ≤0.25 - ≥128 µg/mL; Ceftazidime/Klebsiella oxytoca: ≤0.03 - ≥256 µg/mL; Ceftazidime-avibactam/Citrobacter koseri: ≤0.015 -≥128 µg/mL to ≤0.125 - ≥64 µg/ml; Ceftazidime-avibactam/Klebsiella oxytoca: ≤0.015 - ≥128 µg/mL to ≤0.125 - ≥64 µg/mL; Meropenem/Citrobacter freundii: ≤0.004 - ≥1024 µg/mL; Meropenem/Escherichia coli: ≤0.004 - ≥1024 μg/mL to ≤0.06 - ≥128 μg/mL

8

Antimicrobial	Enterobacterales			P. aeruginosa			Acinetobacter spp.
	S	I	R	S	I	R	S	I	R
Ampicillin	≤8	16	≥32	-	-	-	-	-	-
Ampicillin-sulbactam	≤8	16	≥32	-	-	-	-	-	-
Ceftazidime-avibactam	≤8	-	≥16	≤8	-	≥16	-	-	-
Meropenem-vaborbactam	≤4	8	≥16	-	-	-	-	-	-
Piperacillin-tazobactam	≤8	16	≥32	-	-	-	-	-	-
Cefazolin	≤2	4	≥8	-	-	-	-	-	-
Cefepime	≤2	4-8	≥16	≤8	-	≥16	-	-	-
Cefuroxime	≤8	-	≥16	-	-	-	-	-	-
Ceftazidime	≤4	8	≥16	-	-	-	-	-	-
Aztreonam	≤4	8	≥16	-	-	-	-	-	-
Meropenem	≤1	2	≥4	≤2	4	≥8	≤2	4	≥8
Gentamicin	≤4	8	≥16	≤4	8	≥16	-	-	-
Tobramycin	≤4	8	≥16	-	-	-	-	-	-
Amikacin	≤16	32	≥64	≤16	32	≥64	-	-	-
Tigecycline	≤2	4	≥8	-	-	-	-	-	-
Ciprofloxacin	≤0.25	0.5	≥1	≤0.5	1	≥2	-	-	-
Levofloxacin	≤0.5	1	≥2	≤1	2	≥4	-	-	-
Trimethoprim-sulfamethoxazole	≤2	-	≥4	-	-	-	-	-	-

Table 3: FDA Recognized Susceptibility Test Interpretive Criteria (STIC) / "Breakpoints" implemented in the kit software.

8.3 Intended Use/Indications for Use

Intended Use

The ASTar System is intended to be used for the automated quantitative susceptibility testing for most clinically significant microorganisms. The ASTar System does not provide organism identification.

Indications for Use

The ASTar System, comprised of the ASTar Instrument with the ASTar BC G- Kit (ASTar BC G-Consumable kit, ASTar BC G- Frozen Insert, and ASTar BC G- Kit software), utilizes high-speed, time-lapse microscopy imaging of bacteria for the in vitro, quantitative determination of antimicrobial susceptibility of on-panel gram-negative bacteria. The test is performed directly on positive blood culture samples signaled as positive by a continuous monitoring blood culture

9

system and confirmed to contain gram-negative bacilli by Gram stain. Organism identification is required for AST result interpretation and reporting.

Test results from the ASTar BC G- Kit 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 ASTar BC G- panel, where inconclusive results are obtained, epidemiologic testing, recovery of organisms present in microbial samples, and susceptibility testing of bacteria in polymicrobial samples.

The ASTar BC G- Kit tests the following antimicrobial agents with the following bacterial species:

Amikacin: Citrobacter freundii, Enterobacter cloacae complex, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Ampicillin: Escherichia coli, Proteus mirabilis

Ampicillin-sulbactam: Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris

Aztreonam: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Cefazolin: Klebsiella pneumoniae

Cefepime: Citrobacter freundii, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Ceftazidime: Enterobacter cloacae complex, Escherichia oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Ceftazidime-avibactam: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Klebsiella oxytoca, Proteus mirabilis, Pseudomonas aeruginosa, Serratia marcescens

Cefuroxime: Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis

Ciprofloxacin: Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Gentamicin: Citrobacter freundii, Citrobacter koseri, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Levofloxacin: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

10

Page 8-7

Meropenem: Acinetobacter baumannii, Citrobacter freundii, Citrobacter koseri, Escherichia coli, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens

Meropenem-vaborbactam: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens

Piperacillin-tazobactam: Citrobacter koseri, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Serratia marcescens

Tigecycline: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Serratia marcescens

Tobramycin: Citrobacter freundii, Citrobacter koseri, Enterobacter cloacae complex, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens

Trimethoprim-sulfamethoxazole: Enterobacter cloacae complex, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, Proteus vulgaris

Special Conditions for Use Statements

• · Rx For Prescription Use Only

8.4 Comparison of Technological Characteristics with the Predicate
Device

| Description | Q-linea AB
ASTar BC G- Kit
K221688
(New Device) | Accelerate Diagnostics, Inc.
Accelerate PhenoTest BC Kit
DEN160032
(Predicate Device) |
|-----------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Product Code(s) | SAN, LON | PRH, NSU, PEO, PAM, PEN, LON |
| Primary Regulation | 21 CFR 866.1650 | 21 CFR 866.1650 |
| Device Class | II | II |
| Device Classification | Fully automated short-term
incubation cycle antimicrobial
susceptibility system | Positive Blood Culture Identification
and AST Kit |
| Intended Use/
Indication for Use | The ASTar System is intended to be
used for the automated
quantitative susceptibility testing
for most clinically significant
microorganisms. The ASTar 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 |
| Description | Q-linea AB
ASTar BC G- Kit
K221688
(New Device) | Accelerate Diagnostics, Inc.
Accelerate PhenoTest BC Kit
DEN160032
(Predicate Device) |
| | The ASTar System, comprised of the
ASTar Instrument with the ASTar BC
G- Kit (ASTar BC G- Consumable kit,
ASTar BC G- Frozen Insert, and
ASTar BC G- Kit software), utilizes
high-speed, time-lapse microscopy
imaging of bacteria for the in vitro ,
quantitative determination of
antimicrobial susceptibility of on-
panel gram-negative bacteria. The
test is performed directly on
positive blood culture samples
signaled as positive by a continuous
monitoring blood culture system
and confirmed to contain gram-
negative bacilli by Gram stain.
Organism identification is required
for AST result interpretation and
reporting.

Test results from the ASTar BC G-
Kit 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 ASTar
BC G- panel, where inconclusive
results are obtained, epidemiologic
testing, recovery of organisms
present in microbial samples, and
susceptibility testing of bacteria in
polymicrobial samples. | 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 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. |
| Instrument Required | ASTar Instrument | Accelerate Pheno System |
| Blood Culture Types
Tested | BD BACTEC: Standard/10
Aerobic, Anaerobic; Lytic/10 | BD BACTEC: Standard/10
Aerobic, Anaerobic; Lytic/10 |
| Description | Q-linea AB
ASTar BC G- Kit
K221688
(New Device) | Accelerate Diagnostics, Inc.
Accelerate PhenoTest BC Kit
DEN160032
(Predicate Device) |
| | Aerobic, Anaerobic | Aerobic, Anaerobic |
| | BioMeriuex BacT/ALERT:
Standard Aerobic, Anaerobic;
Plus Aerobic, Anaerobic; PF Plus | BioMeriuex BacT/ALERT:
Standard Aerobic, Anaerobic;
Plus Aerobic, Anaerobic; PF Plus |
| | | Versa TREK:
REDOX 1 and 2 |
| Antimicrobials
Tested | Amikacin
Ampicillin
Ampicillin-sulbactam
Aztreonam
Cefazolin
Cefepime
Ceftazidime
Ceftazidime-avibactam
Cefuroxime
Ciprofloxacin
Gentamicin
Meropenem
Meropenem-vaborbactam
Levofloxacin
Piperacillin-tazobactam
Tobramycin
Tigecycline
Trimethoprim-sulfamethoxazole | Amikacin
Ampicillin
Ampicillin-sulbactam
Aztreonam
Ceftazidime
Ceftaroline
Cefepime
Ceftriaxone
Ciprofloxacin
Daptomycin
Erythromycin
Ertapenem
Gentamicin
Linezolid
Meropenem
Piperacillin-tazobactam
Tobramycin
Vancomycin |
| Organisms Tested
for Antimicrobial
Susceptibility Testing | Gram-Negative Bacteria:
Acinetobacter baumannii
Citrobacter freundii
Citrobacter koseri
Enterobacter cloacae complex
Escherichia coli
Klebsiella aerogenes
Klebsiella oxytoca
Klebsiella pneumoniae
Pseudomonas aeruginosa
Proteus mirabilis | Gram-Negative Bacteria:
Acinetobacter baumannii
Citrobacter spp.
(i.e., Citrobacter freundii,
Citrobacter koseri, not
differentiated)
Enterobacter spp.
(i.e., Enterobacter cloacae,
Enterobacter aerogenes, not
differentiated)
Escherichia coli
Klebsiella spp.
(i.e., Klebsiella pneumoniae |
| Description | Q-linea AB
ASTar BC G- Kit
K221688
(New Device) | Accelerate Diagnostics, Inc.
Accelerate PhenoTest BC Kit
DEN160032
(Predicate Device) |
| | Serratia marcescens | Klebsiella oxytoca, not
differentiated) |
| | | Proteus spp.
(i.e., Proteus mirabilis, Proteus
vulgaris, not differentiated) |
| | | Pseudomonas aeruginosa |
| | | Serratia marcescens |
| | | Gram-Positive Bacteria:
Staphylococcus aureus |
| | | Staphylococcus lugdunensis |
| | | Coagulase-negative Staphylococcus
species (i.e., Staphylococcus
epidermidis, Staphylococcus
haemolyticus, Staphylococcus
hominis, Staphylococcus capitis,
Staphylococcus lugdunensis,
Staphylococcus warnerii, not
differentiated), |
| | | Enterococcus faecalis |
| | | Enterococcus faecium |
| Similarities | | |
| Technology | High-speed, time-lapse microscopy
imaging | Similar |
| Sample Types | Positive Blood Culture | Same |
| Sample Prep | Direct from sample. No manual
McFarland preparation required | Same |
| Results | Minimum Inhibitory Concentration
(MIC) based Antimicrobial
Susceptibility Testing direct from
Positive Blood Cultures | Same |
| Differences | | |
| Sample per
Instrument | 12 samples | 1 sample |
| Description | Q-linea AB
ASTar BC G- Kit
K221688
(New Device) | Accelerate Diagnostics, Inc.
Accelerate PhenoTest BC Kit
DEN160032
(Predicate Device) |
| Types of Results
Provided | Provides AST results only. ID is
required but provided by
alternative method | Provides both ID and AST |
| Types Organisms
Tested | Provides AST results for Gram-
negative bacteria only | Provides ID and AST results for both
Gram-positive and Gram-negative
bacteria |
| Time to AST Results | Approximately 6 hours | Approximately 7 hours |

11

Page 8-8

12

13

14

8.5 Performance Characteristics

The following performance data were provided in support of the substantial equivalence determination.

8.5.1 Reproducibility

Reproducibility studies of the ASTar System (ASTar BC G- Kit run on ASTar Instrument) for positive Gram-negative blood culture bottles, BCBs, included the evaluation of 23 bacterial strains to obtain at least six on-scale MIC values for each antimicrobial. Triplicate samples from each contrived blood culture were tested at three separate sites on at least two separate days (supplementary testing was conducted in-house with three individual instruments). Thus at least six samples for each isolate were tested at each site and each isolate yielded a minimum of 18 results (3 sites x 2 days x 3 replicates). In total, all samples were tested within 16 hours of bottle positivity.

Performance was compared between three sites, with test isolates that are analyzed on at least two separate days to assess inter-site reproducibility and intra-site reproducibility of the ASTar System. The system needed to demonstrate an overall reproducibility of ≥ 95% based on the number of results that fall within ±1 doubling dilution between the test MIC result and test MIC mode. Reproducibility was calculated for both best-case scenario (assumes any off-scale results are within one dilution from the adjacent on-scale result) and worst-case scenario (assumes any off-scale results are more than one dilution from the adjacent on-scale result).

In the initial reproducibility study, inter-site reproducibility was evaluated at three sites and the results are summarized in Table 4. A supplemental reproducibility study was performed with

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three instruments at a single internal site. The aggregated results from the initial and supplementary study are summarized in Table 5.

Table 4. Summary of initial and supplemental reproducibility results from all sites for ASTar BC G- Kit
(by study).
	Initial reproducibility testing		Supplementary testing
Antimicrobial	Best-case¹ (%)	Worst-case² (%)	Best-case¹ (%)	Worst-case² (%)
Amikacin	144/144 (100%)	139/144 (96.5%)	53/53 (100%)	53/53 (100%)
Ampicillin	118/126 (93.7%)	118/126 (93.7%)	36/36 (100%)	36/36 (100%)
Ampicillin-sulbactam	162/162 (100%)	162/162 (100%)	36/36 (100%)	34/36 (94.4%)
Aztreonam	108/108 (100%)	99/108 (91.7%)	0/0 (N/A)³	0/0 (N/A)³
Cefazolin⁴	126/126 (100%)	126/126 (100%)	36/36 (100%)	36/36 (100%)
Cefepime	107/108 (99.1%)	107/108 (99.1%)	35/35 (100%)	35/35 (100%)
Ceftazidime	89/90 (98.9%)	82/90 (91.1%)	18/18 (100%)	13/18 (72.2%)
Ceftazidime-avibactam	89/89 (100%)	79/89 (88.8%)	18/18 (100%)	18/18 (100%)
Cefuroxime	125/125 (100%)	125/125 (100%)	36/36 (100%)	36/36 (100%)
Ciprofloxacin	144/144 (100%)	144/144 (100%)	53/53 (100%)	53/53 (100%)
Gentamicin	108/108 (100%)	108/108 (100%)	53/53 (100%)	53/53 (100%)
Levofloxacin	180/180 (100%)	170/180 (94.4%)	71/71 (100%)	71/71 (100%)
Meropenem	36/36 (100%)	36/36 (100%)	36/36 (100%)	36/36 (100%)
Meropenem-vaborbactam	90/90 (100%)	90/90 (100%)	53/53 (100%)	53/53 (100%)
Piperacillin-tazobactam	233/233 (100%)	233/233 (100%)	53/53 (100%)	53/53 (100%)
Tigecycline	284/288 (98.6%)	284/288 (98.6%)	89/89 (100%)	89/89 (100%)
Tobramycin	263/270 (97.4%)	263/270 (97.4%)	87/89 (97.8%)	87/89 (97.8%)
Trimethoprim-sulfamethoxazole	180/180 (100%)	171/180 (95%)	0/0 (N/A)⁵	0/0 (N/A)⁵

4 Best case scenario calculation for reproducibility assuming the off-scale result is within one well from the mode.

2 Worst case scenario calculation for reproducibility assuming the off-scale result is greater than one well from the mode.

3 After panel alteration the on-scale isolates used for supplemental testing were no longer included in the panel.

4 Reproducibility results are based on testing with indicated species, but not claimed, due to panel alter the study was completed.

5 No isolates with on-scale results for Trimethoxazole were included in the supplementary testing.

All antimicrobials show a reproducibility of ≥ 95% for best-case scenario calculations. For worstcase scenario calculations all antimicrobials show reproducibility above 89% except two that were slightly below, Ceftazidime-avibactam 88.8%. Two antimicrobials (Cefazolin and Meropenem) show reproducibility results based on testing with indicated species, but not claimed, due to panel alteration after reproducibility study completion see Table 5 for additional information.

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Antimicrobial	Best case1	Worst case2
Amikacin	197/197 (100%)	192/197 (97.5%)
Ampicillin	154/162 (95.1%)	154/162 (95.1%)
Ampicillin-sulbactam	198/198 (100%)	196/198 (99%)
Aztreonam	108/108 (100%)	99/108 (91.7%)
Cefazolin3	162/162 (100%)	162/162 (100%)
Cefepime	142/143 (99.3%)	142/143 (99.3%)
Ceftazidime	107/108 (99.1%)	95/108 (88%)
Ceftazidime-avibactam	107/107 (100%)	97/107 (90.7%)
Cefuroxime	161/161 (100%)	161/161 (100%)
Ciprofloxacin	197/197 (100%)	197/197 (100%)
Gentamicin	161/161 (100%)	161/161 (100%)
Levofloxacin	251/251 (100%)	241/251 (96%)
Meropenem4	72/72 (100%)	72/72 (100%)
Meropenem-vaborbactam	143/143 (100%)	143/143 (100%)
Piperacillin-tazobactam	286/286 (100%)	286/286 (100%)
Tigecycline	373/377 (98.9%)	373/377 (98.9%)
Tobramycin	350/359 (97.5%)	350/359 (97.5%)
Trimethoprim-sulfamethoxazole	180/180 (100%)	171/180 (95%)

Table 5. Summary of all reproducibility results from all sites for ASTar BC G- Kit.

1 Best case calculation for reproducibility assuming any off-scale results are within one dilution from the result. 2 Worst case calculation for reproducibility assuming any off-scale results are more than one dilution from the adjacent on-scale result.

3 Reproducibility results are based on testing with indicated species, but not claimed, due to panel alter the study was completed.

4Meropenem reproducibility with all indicated species was 144/144 (100%) for best and worst case scenarios.

8.5.2 Blood Culture Bottle Compatibility

Ten (10) isolates were included in the study; E. coli (x2), K. oxytoca, K. pneumoniae, P. aeruqinosa, P. mirabilis, E. cloacae complex, S. marcescens, K. aerogenes and A. baumannii. These isolates represent the ASTar BC G- Kit panel and were selected to favor resistance phenotypes to provide as many on-scale MIC values as possible. Table 6 lists the BCBs included in this study.

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Manufacturer	BCB Type
bioMérieux	BACT/ALERT FA Plus Aerobic
bioMérieux	BACT/ALERT FN Plus Anaerobic
bioMérieux	BACT/ALERT PF Plus Peds
bioMérieux	BACT/ALERT SN Standard Anaerobic
bioMérieux	BACT/ALERT SA Standard Aerobic
BD	BACTEC Peds Plus medium in plastic culture vials
BD	BACTEC Lytic Anaerobic medium in plastic culture vials
BD	BACTEC Plus Anaerobic medium in plastic culture vials
BD	BACTEC Plus Aerobic medium in plastic culture vials
BD	BACTEC Standard Aerobic medium in plastic culture vials
BD	BACTEC Standard Anaerobic medium in plastic culture vials

Table 6. Blood culture bottles evaluated for ASTar BC G- Kit.

In total 11 different BCB types were evaluated. All ten (10) isolates were run in triplicates in the six aerobic bottles. Eight (8) isolates, excluding A. baumannii and P. aeruginosa, were run in triplicate in the five anaerobic bottles were cultured until positive and run on the ASTar System within 16 hours.

Two methods were used to evaluate the data, first results were evaluated for each antimicrobial by bottle type and by bacteria. The pass criteria were the overall essential agreement (EA) as compared to reference MIC obtained by frozen broth microdilution according to CLSI M07 and shall be ≥90% for each antimicrobial, stratified by bacteria. Additionally, mode MIC values for each antimicrobial were compared across all bottle types. The percentage of MIC values within ±1 doubling dilution of the mode MIC for each antimicrobial/bottle were determined. The overall data from these two analyses are summarized in Table 7.

All bottle types had an MIC value within ±1 doubling dilution to the mode across all bottle types in >95% of all MICs evaluated, indicating that the ASTar System performed similarly across all bottle types.

Table 7. Overall essential agreement with BMD and number of MIC values ±1 to mode values across all
bottle types for non-fastidious antimicrobials in the ASTar BC G- Kit panel.

| Blood culture bottle type | Essential Agreement
with BMD1 | MIC values ±1 from mode value in all
bottles / Total number of MIC values |
|------------------------------|----------------------------------|------------------------------------------------------------------------------|
| BACT/ALERT FA Plus Aerobic | 522/537 (97.2%) | 539/540 (99.8%) |
| BACT/ALERT FN Plus Anaerobic | 478/486 (98.4%) | 488/489 (99.8%) |
| BACT/ALERT PF Plus Peds | 533/537 (99.3%) | 538/540 (99.6%) |

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| Blood culture bottle type | Essential Agreement
with BMD1 | MIC values ±1 from mode value in all
bottles / Total number of MIC values |
|----------------------------------|----------------------------------|------------------------------------------------------------------------------|
| BACT/ALERT SN Standard Anaerobic | 480/486 (98.8%) | 488/489 (99.8%) |
| BACT/ALERT SA Standard Aerobic | 528/537 (98.3%) | 534/540 (98.9%) |
| BACTEC Peds Plus | 534/537 (99.4%) | 540/540 (100%) |
| BACTEC Lytic Anaerobic | 477/486 (98.1%) | 489/489 (100%) |
| BACTEC Plus Anaerobic | 484/486 (99.6%) | 489/489 (100%) |
| BACTEC Plus Aerobic | 536/537 (99.8%) | 539/540 (99.8%) |
| BACTEC Standard Aerobic | 532/537 (99.1%) | 539/540 (99.8%) |
| BACTEC Standard Anaerobic | 481/486 (99.0%) | 489/489 (100%) |

1Essential Agreement 18-24 hours² | 16-18 hours | >18-24 hours |
| Amikacin | 1/1 (100%) | 24/24 (100%) | 3/3 (100%) | 23/23 (100%) |
| Ampicillin | | 5/5 (100%) | 3/3 (100%) | 3/3 (100%) |
| Ampicillin-sulbactam | | 17/17 (100%) | 3/3 (100%) | 15/15 (100%) |
| Aztreonam | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Cefazolin | | 14/14 (100%) | 3/3 (100%) | 12/12 (100%) |
| Cefepime | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Ceftazidime | 1/1 (100%) | 24/24 (100%) | 3/3 (100%) | 23/23 (100%) |
| Ceftazidime-avibactam | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Cefuroxime | | 17/17 (100%) | 3/3 (100%) | 14/14 (100%) |
| Ciprofloxacin | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Gentamicin | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Levofloxacin | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Meropenem | 1/1 (100%) | 24/24 (100%) | 3/3 (100%) | 23/23 (100%) |
| Meropenem-vaborbactam | | 19/19 (100%) | 3/3 (100%) | 17/17 (100%) |
| Piperacillin-tazobactam | | 22/22 (100%) | 3/3 (100%) | 19/20 (95.0%) |
| Tigecycline | | 17/17 (100%) | | 16/17 (94.2%) |
| Tobramycin | 1/1 (100%) | 21/21 (100%) | 3/3 (100%) | 20/20 (100%) |
| Trimethoprim-sulfamethoxazole | | 19/19 (100%) | 3/3 (100%) | 17/17 (100%) |

Table 8. Stability of samples loaded to the ASTar System within different timeframes after BCB positivity for each time/incubation condition. The format is "number of MIC values ±1 from mode MIC values in initial sample/total MIC values" ("pass rate in %").1

1 Data also includes indicated species, but not claimed, due to panel alteration after the study was completed.

2 one RT sample (AS503 S. marcescens HV1056) was loaded at 24 hours and 49 minutes after positivity. One initial sample and one RT sample (AS5056 and A55059, E. cloacae QM336) were by mistake removed from blood culture cabinet and loaded in ASTar before turning positive. These samples were excluded from analysis and re-run with new BCB inoculations.

Pass/fail criteria were >95% of MIC values within ±1 doubling dilution of the mode MIC of initial samples (loaded 12,000 WBC/μL
Leukopenia
95% pass rate as compared to control samples without interfering antibiotics, see Table 13.

Table 13. Test results for each evaluated potentially interfering antibiotic are shown, with pass rate (%) as compared to control mode/median MIC values for the ASTar BC G- Kit.2

| Interferent | BCB type | Number of MIC values ±1 from
mode value in control / Total
number of evaluated MIC
values | Pass Rate |
|---------------|--------------------------------|----------------------------------------------------------------------------------------------------|-----------|
| Cefotaxime | BD BACTEC Plus Aerobic | 191/194 | 98.5% |
| | BACT/ALERT SA Standard Aerobic | 192/192 | 100% |
| Ciprofloxacin | BD BACTEC Plus Aerobic | 194/194 | 100% |
| | BACT/ALERT SA Standard Aerobic | 189/195 | 96.9% |
| Meropenem | BD BACTEC Plus Aerobic | 158/159 | 99.4% |
| | BACT/ALERT SA Standard Aerobic | 152/158 | 96.2% |

4Pass rates 5 x 107 CFU/mL, the concentration was assessed and adjusted successfully by the ASTar System for 95.8% (23/24) of samples and 100% of those (23/23), produced an inoculum within the acceptance ranges for AST, see Table 14. Despite being below the range commonly observed in positive Gram-negative BCB, the ASTar System was able to assess and adjust the bacterial concentration in 75% (9/12) samples and accurately produce an inoculum within the acceptance ranges in 88.9% (8/9) of those samples. As expected, all dilutions with a concentration