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 Enterobacteriaceae and Non-Enterobacteriaceae and most 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 imipenem at concentrations of 1-16 ug/mL to Gram-negative ID/AST or AST only Phoenix panels. Imipenem has been shown to be active in vitro against most strains of microorganisms listed below, as described in the FDA-approved package insert for this antimicrobial agent.

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 containing biochemicals 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 preliminarily identified as a Gram-negative or Gram-positive isolate. For each isolation 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 bacterial growth. Each AST panel configuration contains several 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℃. 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

Here's a breakdown of the acceptance criteria and the study details for the BD Phoenix™ Automated Microbiology System - Imipenem 1-16 µg/mL, based on the provided document:

Acceptance Criteria and Device Performance

Acceptance Criteria	Reported Device Performance (Imipenem)
Overall Intra-site Reproducibility (>90%)	>90%
Overall Inter-site Reproducibility (>95%)	>95%
Essential Agreement (EA) with Reference	97.2% (n=2680)
Category Agreement (CA) with Reference	96.8% (n=2680)

Study Details

Sample size used for the test set and the data provenance:
- Sample Size: 2680 isolates for Essential Agreement (EA) and Category Agreement (CA).
- Data Provenance: Clinical, stock, and challenge isolates. These were collected across multiple geographically diverse sites across the United States. The study compared Phoenix System results to expected results (for challenge isolates) and to the NCCLS reference broth microdilution method (for clinical isolates).
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 for establishing ground truth. The ground truth for clinical isolates was established by the NCCLS reference broth microdilution method, which is a standardized laboratory procedure, not typically expert consensus in the way a radiologist might interpret an image. For challenge isolates, "expected results" were used, which implies a known truth for those specific strains.
Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- The document does not describe an adjudication method in the context of expert review. The comparison was primarily against a reference laboratory method (NCCLS broth microdilution) or pre-determined expected results for challenge isolates.
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:
- This was not an MRMC comparative effectiveness study involving human readers with or without AI assistance. The device itself is an automated system for antimicrobial susceptibility testing; it assists microbiologists by automating a lab process, not by interpreting results that would otherwise be interpreted by a human expert in the same way a radiologist reads an image.
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Yes, the performance presented (EA and CA) is for the standalone device (BD Phoenix™ Automated Microbiology System) compared to the reference method. While a human inoculates the panel and inputs it into the system, the interpretation of results (MIC values and categories S, I, R) is automated by the device's software.
The type of ground truth used:
- Reference Method: For clinical isolates, the ground truth was established using the NCCLS reference broth microdilution method (AST panels prepared according to NCCLS M7).
- Expected Results: For challenge isolates, "expected results" were used, implying a pre-defined or known susceptibility profile for those specific challenge strains.
The sample size for the training set:
- The document does not explicitly state the sample size for the training set. It describes the "Clinical Studies" and "Site Reproducibility" for validation, but does not differentiate or quantify a separate training set. Given the context of a 510(k) for an automated lab instrument, the development and verification/validation processes might involve internal data sets not explicitly detailed in this summary.
How the ground truth for the training set was established:
- As the training set size is not specified, the method for establishing its ground truth is also not explicitly detailed. However, for such devices, it would typically involve similar reference methods (like NCCLS broth microdilution) to develop and calibrate the algorithms that interpret the redox indicator changes and bacterial turbidity.

Summary

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SEP 2 9 2003

510(K) SUMMARY

SUBMITTED BY:	Becton, Dickinson and Company7 Loveton CircleSparks, MD 21152Phone: (410) 316 - 4778Fax: 410-316-4499
CONTACT NAME:	Michelle B. BandyRegulatory Affairs Specialist
DATE PREPARED:	July 22, 2003
DEVICE TRADE NAME:	BD Phoenix™ Automated Microbiology System -Imipenem 1-16 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:

BD Phoenix instrument and software. .
BD Phoenix panels containing biochemicals 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.

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DEVICE COMPARISON:

The BD Phoenix™ Automated Microbiology System demonstrated substantially equivalent performance when compared with the NCCLS reference broth microdilution method. This premarket notification provides data supporting the use of the BD Phoenix™ Automated Microbiology System Gram-negative ID/AST or AST only Phoenix 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 prepared according to NCCLS M7). The system has been evaluated as defined in the FDA Draft guidance document, "Guidance on Review 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 evaluated at three sites using a panel of Gram-negative isolates. Each site tested the isolates in triplicate on three different days using one lot of Gram-negative 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 reproducibility of greater than 90% and an overall inter-site reproducibility greater than 95% for the Gram-negative 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-negative Phoenix panel format containing this antimicrobial agent. Phoenix System results for Challenge set isolates were compared to the expected results. Phoenix System results for clinical isolates were compared to the results obtained from the NCCLS reference broth microdilution method.

The performance of the Phoenix System was assessed by calculating Essential Agreement (EA) and Category Agreement (CA) to expected/reference results for all isolates tested. Essential Agreement (EA) occurs when the BD Phoenix™ Automated Microbiology System agrees exactly or within + one two-fold dilution to the reference result. Category Agreement (CA) occurs when the BD Phoenix™ 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.

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

Antimicrobial	Concentration	EA (n)	EA (%)	CA (n)	CA (%)
Imipenem	1-16 $\mu$ g/mL	2680	97.2	2680	96.8

Conclusions Drawn from Substantial Equivalence Studies

The data collected from the substantial equivalence studies demonstrate that testing on the BD Phoenix™ Automated Microbiology System with this antimicrobial agent is substantially equivalent as outlined in the FDA draft guidance document, "Guidance on Review Criteria for Assessment of Antimicrobial Susceptibility Devices", March 8, 2000. Technological characteristics of this system are substantially 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 Gatifloxacin (K020321, May 23, 2002), Ofloxacin (K020323, April 14, 2002), and Levofloxacin (K020322, March 27, 2002).

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DEPARTMENT OF HEALTH & HUMAN SERVICES

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 caduceus symbol, which is a staff with two snakes coiled around it, and the text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" arranged in a circular pattern around the symbol. The symbol is black, and the text is also black.

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Ms. Michelle B. Bandy Regulatory Affairs Specialist BD Diagnostics Systems Becton, Dickinson and Company 7 Loveton Circle Sparks, MD 21152

SEP 2 9 2003

Ms. Michelle B. Bandy
Regulatory Affairs Specialist
BD Diagnostics Systems
Becton, Dickinson and Company
7 Loveton Circle
Sparks, MD 21152

SEP 2 9 2003

Ms. Michelle B. Bandy
Regulatory Affairs Specialist
BD Diagnostics Systems
Becton, Dickinson and Company
7 Loveton Circle
Sparks, MD 21152

Re: K032275

Trade/Device Name: BD Phoenix™ Automated Microbiology Systems Imipenem (1-16 ug/ml) Regulation Number: 21 CFR 866.1645 Regulation Name: Fully Automated Short-Term Incubation Cycle Antimicrobial Susceptibility Devices Regulatory Class: Class II Product Code: LON Dated: July 22, 2003

Received: July 23, 2003

Dear Ms. Bandy:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); and good manufacturing practice 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) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific information about the application of labeling requirements to your device, or questions on the promotion and advertising of your device, please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 594-3084. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely yours.

Steven Putman

Steven I. Gutman, M.D., M.B.A. Director 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: K031275

BD Phoenix™ Automated Microbiology System for use with the antimicrobial agent Device Name: imipenem (1-16 ug/mL) - Gram-negative ID/AST or AST only Phoenix panels.

Indications for Use:

Active In Vitro and in Clinical Infections Against:

Acinetobacter spp. Citrobacter spp. Enterobacter spp.

Escherichia coli Klebsiella spp. Morganella morganii. Pseudomonas aeruginosa Serratia spp.

Active In Vitro Against:

Aeromonas hydrophila Alcaligenes faecalis

' Providencia stuartii

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Sargottens 9/25/03
Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

Over-the-Counter Use

KO32275 210(K)

BD Diagnostic Systems Becton, Dickinson and Company

Prescription Use

(Per 21 CFR 801.109)

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.”