The BD Phoenix™ Automated Microbiology System is intended for the rapid identification and in vitro antimicrobial susceptibility testing of isolates from pure culture of most aerobic and facultative anaerobic Gram-negative and Gram-positive bacteria of human origin.

The BD Phoenix™ Automated Microbiology System is intended for in vitro quantitative determination of antimicrobial susceptibility by minimal inhibitory concentration (MIC) of most Gram-negative aerobic and facultative anaerobic bacteria isolates from pure culture for Enterobacteriaeae and Non-Enterobacteriaeae and Gram-positive bacteria isolates from pure culture belonging to the genera Staphylococcus and Enterococcus.

This premarket notification is for the addition of the antimicrobial agent Cefazolin at concentrations of 2-32 µg/mL to Gram Positive ID/AST or AST only Phoenix panels. Cefazolin has been shown to be active in vitro and in clinical infections against: Staphylococcus aureus (including penicillinase-producing strains) and Staphylococcus epidermidis.

Device Description

The BD Phoenix Automated Microbiology System (Phoenix System) is an automated system for the rapid identification (ID) and antimicrobial susceptibility testing (AST) of clinically relevant bacterial isolates. The system includes the following components:

BD Phoenix instrument and software.
BD Phoenix panels for organism ID testing and antimicrobial agents for AST determinations.
BD Phoenix ID Broth used for performing ID tests and preparing AST Broth inoculum.
BD Phoenix AST Broth used for performing AST tests only.
BD Phoenix AST Indicator solution added to the AST Broth to aid in bacterial growth determination.

The Phoenix panel is a sealed and self-inoculating molded polystyrene tray with 136 micro-wells containing dried reagents. Organisms for susceptibility testing must be a pure culture and preliminary identification as a Gram-negative or Gram-positive isolate. For each isolate, an inoculation suspension equivalent to a 0.5 McFarland standard is prepared in Phoenix ID broth.

The Phoenix AST method is a broth based microdilution test. The Phoenix system utilizes a redox indicator for the detection of organism growth in the presence of an antimicrobial agent. Measurements of changes to the indicator as well as bacterial turbidity are used in the determination of organism growth. The Phoenix panels contain various antimicrobial agents with a wide range of two-fold doubling dilution concentrations.

The instrument houses the panels where they are continuously incubated at a nominal temperature of 35 degrees Celsius. The instrument takes readings of the panels every 20 minutes. The readings are interpreted to give an identification of the isolate, minimum inhibitory concentration (MIC) values and category interpretations, S, I, or R (sensitive, intermediate, or resistant).

AI/ML Overview

Acceptance Criteria and Study Details for BD Phoenix™ Automated Microbiology System - Cefazolin 2-32 µg/mL

1. Table of Acceptance Criteria and Reported Device Performance

The provided document defines the acceptance criteria in terms of "Essential Agreement (EA)" and "Category Agreement (CA)" with the NCCLS reference broth microdilution method. The performance is summarized in Table 1.

Metric	Acceptance Criteria (Implied)	Reported Device Performance for Cefazolin (Gram-Positive Organisms)
Essential Agreement (EA)	Not explicitly stated as a minimum percentage, but the study "demonstrated substantially equivalent performance" when compared to the NCCLS reference method. Typically, for AST devices, this is often >90% or >95%. Here, it's implied that the observed 100% is acceptable.	100% (n=507)
Category Agreement (CA)	Not explicitly stated as a minimum percentage, but the study "demonstrated substantially equivalent performance" when compared to the NCCLS reference method. Typically, for AST devices, this is often >90% or >95%. Here, it's implied that the observed 100% is acceptable.	100% (n=507)

Note: While specific numeric acceptance criteria (e.g., "EA > 95%") are not explicitly listed in the provided text, the conclusion that the device "demonstrates substantially equivalent performance" based on the observed 100% EA and CA strongly implies that these results met the internal or regulatory acceptance thresholds for substantial equivalence under the FDA Draft guidance document, "Guidance on Review Criteria for Assessment of Antimicrobial Susceptibility Devices," March 8, 2000.

2. Sample size used for the test set and the data provenance

Sample Size for Test Set: 507 isolates (n=507) of Gram-positive organisms.
Data Provenance:
- Country of Origin: United States. The study states, "Clinical, stock and challenge isolates were tested across multiple geographically diverse sites across the United States."
- Retrospective or Prospective: Not explicitly stated as retrospective or prospective for the clinical isolates. However, the testing of "stock and challenge isolates" alongside "clinical isolates" suggests a methodology that combines existing collections (stock/challenge, which could be considered retrospective or curated) with potentially newly acquired clinical isolates (prospective or concurrent). The overall context of a premarket study for a new antimicrobial agent addition to an existing system often involves a mix to ensure comprehensive evaluation.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

The document does not specify the number of experts or their qualifications. The "ground truth" (reference results) was established using the NCCLS reference broth microdilution method. This method is a standardized laboratory procedure, not typically dependent on expert interpretation for establishing the result itself, but rather on adherence to the protocol by trained laboratory personnel.

4. Adjudication method for the test set

The document does not describe an adjudication method involving multiple human readers or experts for the test set. The comparison was made between the BD Phoenix System results and the results obtained from the NCCLS reference broth microdilution method, which is a direct, standardized laboratory assay.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

No, a multi-reader, multi-case (MRMC) comparative effectiveness study was not done.

This device (BD Phoenix Automated Microbiology System) is an automated system for antimicrobial susceptibility testing, which provides automated results (MIC values and categorical interpretations). It does not involve human "readers" interpreting images or clinical data where AI assistance would be applicable in the typical sense of an MRMC study for imaging or clinical decision support. The system is the "AI" (or automated algorithm) that performs the test and provides the interpretation.

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

Yes, a standalone performance study was done.

The entire study described is a standalone performance evaluation of the "BD Phoenix™ Automated Microbiology System" (the device/algorithm) against the reference method. The system inherently operates as an "algorithm only" in generating the MIC and susceptibility category interpretations. There is no mention of a human-in-the-loop component being evaluated or integrated into the performance claims for this specific study; the device itself provides the final result.

7. The type of ground truth used

The type of ground truth used was NCCLS reference broth microdilution method. This is a laboratory reference standard (gold standard biological assay) for determining antimicrobial susceptibility, widely accepted in microbiology.

8. The sample size for the training set

The document does not specify a separate "training set" or its sample size. The description focuses on the validation of the Cefazolin agent on the existing BD Phoenix system. Automated microbiology systems typically rely on pre-established algorithms and decision rules derived from extensive historical data and expert panels during their initial development. The current submission is for an addition of an antimicrobial agent to an already established system, so the performance evaluation is focused on the new agent's accuracy with the existing system, rather than a de novo algorithm training.

9. How the ground truth for the training set was established

As no separate "training set" is explicitly mentioned for this specific submission, the method for establishing its ground truth is not provided in the document. For the development of the core BD Phoenix system itself, ground truth for algorithm training would have historically been established through extensive testing against reference methods like NCCLS broth microdilution, often corroborated with expert microbiological interpretation over many years of data collection.

Summary

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510(k) SUMMARY

SUBMITTED BY:	Becton, Dickinson and Company7 Loveton CircleSparks, MD 21152Phone: 410.316-4287Fax: 410.316-4499
CONTACT NAME:	Monica GiguereRA Specialist, Regulatory Affairs
DATE PREPARED:	April 11, 2005
DEVICE TRADE NAME:	BD Phoenix™ Automated Microbiology System -Cefazolin 2-32 µg/mL
DEVICE COMMON NAME:	Antimicrobial susceptibility test system-short incubation
DEVICE CLASSIFICATION:	Fully Automated Short-Term Incubation Cycle AntimicrobialSusceptibility Device, 21 CFR 866.1645
PREDICATE DEVICES:	VITEK® System (PMA No. N50510) and BD Phoenix™Automated Microbiology System with Gatifloxacin (K020321,May 23, 2002), Ofloxacin (K020323, April 14, 2002), andLevofloxacin (K020322, March 27, 2002).
INTENDED USE:	The BD Phoenix™ Automated Microbiology System isintended for the rapid identification and in vitro antimicrobialsusceptibility testing of isolates from pure culture of mostaerobic and facultative anaerobic Gram-negative and Gram-positive bacteria of human origin.

DEVICE DESCRIPTION:

The BD Phoenix Automated Microbiology System (Phoenix System) is an automated system for the The BD Phoenix Automated Microbiology of Steeting (AST) of clinically relevant bacterial isolates. The system includes the following components:

BD Phoenix instrument and software. .
BD Flioenix instrument and solvirals for organism ID testing and antimicrobial agents . or AST determinations.
of AST deceminations:
BD Phoenix ID Broth used for performing ID tests and preparing AST Broth inoculum. .
BD Phoenix AST Broth used for performing AST tests only. .
DD Fhoenix AST Brom assurrer posseded to the AST Broth to aid in bacterial growth . determination.

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The Phoenix panel is a sealed and self-inoculating molded polystyrene tray with 136 micro-wells I The Filocins panel is a secured and over for susceptibility testing must be a pure culture and containing urica reagens. Organisms ion or Gram-positive isolate. For each isolate, an inoculation premimatiry tooners of the Farland standard is prepared in Phoenix ID broth.

The Phoenix AST method is a broth based microdilution test. The Phoenix system utilizes a redox I he I noonia AST method if a ganism growth in the presence of an antimicrobial agent. Indicator for the detection of organism go as well as bacterial turbidity are used in the determination Measurents of thanges to the marcates ageral antimicrobial agents with a wide range of two-fold doubling dilution concentrations.

The instrument houses the panels where they are continuously incubated at a nominal temperature of The instrument takes readings of the panels every 20 minutes. The readings are interpreted to give an identification of the isolate, minimum inhibitory concentration (MIC) values and category interpretations, S, I, or R (sensitive, intermediate, or resistant).

DEVICE COMPARISON:

The BD Phoenix™ Automated Microbiology System demonstrated substantially equivalent performance when compared with the NCCLS reference broth microdilution method. This premarket performatics when somporting the use of the BD Phoenix™ Automated Microbiology System hourieanon provides and cappermise hoenix panels with this antimicrobial agent.

SUMMARY OF SUBSTANTIAL EQUIVALENCE TESTING:

The BD Phoenix™ Automated Microbiology System has demonstrated substantially equivalent performance when compared to the NCCLS reference broth microdilution method (AST panels performance with compared to the research has been evaluated as defined in the FDA Draft prepared according to FFOOD 117). The of Criteria for Assessment of Antimicrobial Susceptibility Devices", March 8, 2000.

Site Reproducibility

Intra- and inter-site reproducibility of this antimicrobial agent in the BD Phoenix System was millia- and micr-site reproductions) of Gram-positive isolates. Each site tested the isolates in e valuated at three different days using one lot of Gram Positive Phoenix panels containing this antimicrobial agent and associated reagents.

The results of the study demonstrate for the this antimicrobial agent there was an overall intra-site The results of the study demonentals to: an overall inter-site reproducibility greater than 95% for the Gram-positive isolates tested.

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Clinical Studies

Clinical, stock and challenge isolates were tested across multiple geographically diverse sites across the United States to demonstrate the performance of the Phoenix antimicrobial susceptibility test with the Gram Positive Phoenix Panel format containing this antimicrobial agent. Phoenix System results the Challenge set isolates were compared to the expected results. Phoenix System results for clinical ior Charlenge bot bolates nor results obtained from the NCCLS reference broth microdilution method.

The performance of the Phoenix System was assessed by calculating Essential Agreement (EA) and The performance of the I no expected/reference results for all isolates tested. Essential Agreement Calegory Agreement (OT) to expected Microbiology System agrees exactly or within ± one two-fold dilution to the reference result. Category Agreement (CA) occurs when the BD oncenix™ Automated Microbiology System agrees with the reference method with respect to the FDA categorical interpretive criteria (susceptible, intermediate, and resistant).

Table 1 summarizes the performance for the isolates tested in this study.

Performance of BD Phoenix System for Gram-Positive Organisms by Drug Table 1:

a different of the same of the said the same of the same of the same of theAntimicrobial	------------------------------------------------------------------------------------------------------------------------------------------------------------------------------The contract and particular procession in accession in accession in accession in accession in accession in accession in accession in accession in accession in accession in acConcentration	The first of the many of the comments of the first of the first ofEA (n)	Free of Canadian Cases on and Concession of Concession of Concession of Concession of Concessional Concessional Concession of Concessional of Concessional of Concessional ofEA (%).	House and can and andCA (n)------------------------------------------------------------------------------------------------------------------------------------------------------------------------------	The family of the first of the firstCA (%)------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Carren Comments of Children Comments of ChildrenThe Comments and College and College of Concess ofACefazolin	Concession from on an every of they in formTHE LEAST LE LEASE LEASE LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEAST LEASTAnd Concession Company of Children------------------------------------------------------------------------------------------------------------------------------------------------------------------------------2-32 ug/mL	Children assess as compare of concession in any507	00 51 - 1 - 1 -	507	00 7

Conclusions Drawn from Substantial Equivalence Studies

The data collected from the substantial equivalence studies demonstrate that testing on the BD The udia conceded from the odiolany System with this antimicrobial agent is substantially equivalent as outlined in the FDA draft guidance document, "Guidance on Review Criteria for Assessment of as outined in the I Dri drit garames" March 8, 2000. Technological characteristics of this system Amilificantially equivalent to those used in the VITEK® system, which received approval by the FDA under PMA number N50510 and BD Phoenix™ Automated Microbiology System with I Dri under 1 (K020321, May 23, 2002), Ofloxacin (K020323, April 14, 2002), and Levofloxacin (K020322, March 27, 2002).

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Image /page/3/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized eagle with three curved lines representing its wings. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the eagle.

APR 1 4 2005

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Ms. Monica Giguere RA Specialist, Regulatory Affairs BD Diagnostics Systems Becton, Dickinson and Company 7 Loveton Circle Sparks, MD 21152

K050555 Re: K050335
Trade/Device Name: BD Phoenix™ Automated Microbiology System Cefazolin (2-32 µg/mL) - Gram-Postive ID/AST or AST Regulation Number: 21 CFR 866.1645 Regulation Name: 21 CFTC 000.1015
Regulation Name: Fully Automated Short-Term Incubation Cycle Antimicrobial Susceptibility Devices Regulatory Class: Class II Product Code: LON Dated: March 1, 2005 Received: March 3, 2005

Dear Ms. Giguere:

We have reviewed your Section 510(k) premarket notification of intent to market the indication We have reviewed your Section >10(x) premation is suivalent (for the indications
referenced above and have determined the device is subscreen in interstate referenced above and have delemined the devices marketed in interstate
for use stated in the enclosure) to legally marketed president device Amendments for use stated in the enclosure) to legally manced production Device Amendments, or to
commerce prior to May 28, 1976, the enactment as ansieral of the Federal Food. Drug commerce prior to May 28, 1970, the chaculteners with the provisions of the Federal Food, Drug, devices that have been recuire approval of a proval at a proval application (PMA).
and Cosmetic Act (Act) that do not require approval of a provisions of the Act . The and Cosmetic Act (Act) that do not require approval controls provisions of the Act. The Act. The You may, therefore, market the device, sayler to tire gents for annual registration, listing of
general controls provisions of the Act include required withing and general controls provisions of the receined requirements of the management misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), If your device is classified (See adove) ntrols. Existing major regulations affecting your device.
It may be subject to such additional controls. Existing major regulation it may be subject to such additional controls. Existing mayor regals.800 to 895. In addition, FDA
can be found in Title 21, Code of Federal Regulations (CFR), Parts Registe can be found in Title 21, Code of Pederal Regaralises (1) (1) = ) = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

Please be advised that FDA's issuance of a substantial equivalence determination does not mean Please be advised that FDA s issualited on a substitution with other requirements of the Act
that FDA has made a determination that your device and two Edgerains. You must that FDA has made a determination inal your devices by other Federal agencies. You must
or any Federal statutes and regulations administered by other registration and listi or any Federal statures and regilations annings, but not lied to: registration and listing (21
comply with all the Act's requirements, including, on anonomonomonmonmonmentice comply with all the Act s requirements, including, and good manufacturing practice
CFR Part 807); labeling (21 CFR Parts 801 and 809); and good manufacturing practice CFR Part 807); labeling (21 CFR Parts 601 and 607);
requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).

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Page 2 -

This letter will allow you to begin marketing your device as described in your Section 510(k)
the same of the secure of alience for betweenes of your device to a legal This letter will allow you to begin marketing your advice of your device of your device to a legally
premarket notification. The FDA finding of substantial equivale and this premarket notification. The IDA inding of Justillation for your device and thus, permits your device to proceed to the market.

If you desire specific information about the application of labeling requirements to your device, a If you desire spectile information and advertising of your device, please contact the Office of In
or questions on the promotion and advertising of your device, please pote t or questions on the promotion and advertising of Jour 2015-0484. Also, please note the Vitro Diagnostic Device Evaluation and Barey at (210-210).
regulation entitled, "Misbranding by reference to premarket notification weder the Ast from the regulation entitled, "Misoranding of reichers on your responsibilities under the Act from the You may obtain other general informational and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address (000) 050-2012 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11

Sincerely yours,

Sales a form

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

Enclosure

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Page 1 of 1

510(k) Number: _ K 05 05 5 5

Device Name: BD Phoenix™ Automated Microbiology System for use with the antimicrobial agent Device Name. " DD Frioomira - Gram positive ID/AST or AST only Phoenix panels.

Indications for Use:

The BD Phoenix™ Automated Microbiology System is intended for in vitro quantitative determination of The BD Phoenix™ Automatics witchoology Bystem in ation (MIC) of most Gram-negative aerobic
antimicrobial susceptibility by minimal inhibitory concentration (MIC) of most Nega and facultative anaerobic bacteria isolates from pure culture for Enterobacteriaeae and Nonand facultative anactoric bacteria isolates from pure culture belonging to the genera Staphylococcus and Enterococcus.

This premarket notification is for the addition of the antimicrobial agent oefarzolin at concentrations of This premarket nothcation is for the addition of the animalized and only of the many of 2-32 µgmL to Grain Fostive D7701 of NOT off Processions is described in the FDA-approved package insert for this antimicrobial agent.

Active In Vitro and in Clinical Infections Against:

Staphylococcus aureus (including penicillinase-producing strains) Staphylococcus epidermidis

Prescription Use _ ブ (Per 21 CFR 801.109) Over-the-Counter Use

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Division Signature
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Office of In Vitro Diagnostic Device Evaluation and Safety

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BD Diagnostic SystemsBecton, Dickinson and Company	510(k) K05 0555
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Regulation Number and Section

§ 866.1645 Fully automated short-term incubation cycle antimicrobial susceptibility system.

(a)
Identification. A fully automated short-term incubation cycle antimicrobial susceptibility system is a device that incorporates concentrations of antimicrobial agents into a system for the purpose of determining in vitro susceptibility of bacterial pathogens isolated from clinical specimens. Test results obtained from short-term (less than 16 hours) incubation are used to determine the antimicrobial agent of choice to treat bacterial diseases.(b)
Classification. Class II (special controls). The special control for this device is FDA's guidance document entitled “Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA.”