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 anacrobic 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 confirmatory ESBL Test to Gram-negative ID/AST or AST only Phoenix panels. The Phoenix confirmatory ESBL Test is a confirmatory test for the detection of the organisms that produce extended spectrum 3-lactamses (ESBL) in Escherichia coli, Klebsiella pneumoniae, and Klebsiella oxytoca.

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 isolate, an inoculation 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°C. 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 an analysis of the provided text, outlining the acceptance criteria and study details:

Acceptance Criteria and Device Performance for BD Phoenix™ Automated Microbiology System - confirmatory ESBL Test (K033458)

1. Table of Acceptance Criteria and Reported Device Performance

Performance Metric	Acceptance Criteria (Implied)	Reported Device Performance
Overall Percent Agreement	Not explicitly stated, but typically >90% for AST devices to demonstrate substantial equivalence.	96.2%
Positive Percent Agreement (PPA)	Not explicitly stated, but typically >90%.	96.8%
Negative Percent Agreement (NPA)	Not explicitly stated, but typically >90%.	96.1%
Intra-site Reproducibility	>90%	>90%
Inter-site Reproducibility	>95%	>95%

Note: The acceptance criteria for the agreement percentages (Overall, Positive, Negative) are not explicitly stated as numerical targets in the provided text. However, for a 510(k) submission to demonstrate substantial equivalence, agreement percentages typically need to be high (e.g., often >90%) when compared to a reference method, which the reported performance meets.

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

Sample Size:
- Clinical Isolates: The exact number of clinical isolates is not specifically provided, but they were collected across multiple geographically diverse sites across the United States.
- Challenge Isolates: 30 previously characterized challenge organisms were tested at one site. The total number of challenge isolates contributing to the agreement percentages is not explicitly stated beyond these 30, but the overall results involved 1001 tests (963 agreement / 1001 total). It's reasonable to infer that the 1001 tests comprised a combination of clinical and challenge isolates.
- Reproducibility Test: "a panel of Gram-negative isolates" tested in triplicate on three different days. Specific number not provided, but at "three sites".
Data Provenance: Retrospective and Prospective.
- Clinical Isolates: Compared to concurrent testing in the NCCLS reference broth microdilution method. This implies prospective collection or concurrent testing within the study. "Clinical, stock and challenge isolates were tested across multiple geographically diverse sites across the United States."
- Challenge Isolates: These were "previously characterized organisms" (retrospective characterization), but the testing with the Phoenix system was likely prospective within the study.
- Site Reproducibility: Likely prospective testing conducted specifically for the study.
- Overall: The data came from "multiple geographically diverse sites across the United States."

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

The ground truth for the test set was established by the NCCLS reference broth microdilution method rather than human expert consensus for clinical isolates.
For Challenge organisms, the "expected results" acted as the ground truth. The process for generating these "expected results" is described as "previously characterized," suggesting prior microbiological expert determination or established methods.
No information is provided about the number of human experts or their specific qualifications (e.g., microbiologists, lab technologists) involved in performing the NCCLS reference method or characterizing the challenge organisms, as these methods themselves are the gold standard.

4. Adjudication Method for the Test Set

None in the traditional sense of multiple human readers resolving discrepancies.
The comparison was directly between the BD Phoenix™ Automated Microbiology System's results and the results obtained from the NCCLS reference broth microdilution method (for clinical isolates) or "expected results" (for challenge isolates). Any discrepancies would presumably be analyzed against the reference standard.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No, an MRMC comparative effectiveness study was not performed. This device is an automated antimicrobial susceptibility test system, not an imaging or diagnostic AI system designed to assist human readers. Therefore, the concept of improving human reader performance with AI assistance does not apply.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Yes, a standalone performance evaluation was done. The entire study evaluates the performance of the BD Phoenix™ Automated Microbiology System (an automated algorithm/device) directly against a reference method without any human interpretation of the Phoenix system's output needing to be part of the "performance" calculation for the device itself. Human operators perform the initial sample preparation and load the panels, but the interpretation and results are generated automatically by the system.

7. The Type of Ground Truth Used

Reference standard/method:
- For clinical isolates: NCCLS reference broth microdilution method.
- For challenge isolates: "Expected results" based on "previously characterized organisms," implying a highly reliable characterization method often considered a gold standard in microbiology.

8. The Sample Size for the Training Set

Not explicitly stated within the provided text. The document focuses on the validation or performance studies for this specific confirmatory ESBL test addition. While it mentions the general BD Phoenix system has demonstrated equivalence previously, details about its initial training data are not included in this 510(k) summary for the ESBL test.

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

Not applicable / Information not provided. Since the sample size for the training set is not mentioned, the method for establishing its ground truth is also not available in this document. Given the device's nature (automated testing using dried reagents and redox indicators), "training" might involve calibration and optimization against established reference strains and methods rather than a distinct "training set" in the machine learning sense. The summary focuses on the validation of the ESBL test's performance.

Summary

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K033458

MAY 2 8 2004	510(K) SUMMARY
SUBMITTED BY:	Becton, Dickinson and Company7 Loveton CircleSparks, MD 21152Phone: (410) 316-4287Fax: 410-316-4499
CONTACT NAME:	Monica Evelyn GiguereRegulatory Affairs Specialist
DATE PREPARED:	May 27, 2004
DEVICE TRADE NAME:	BD Phoenix™ Automated Microbiology System -confirmatory ESBL Test
DEVICE COMMON NAME:	Antimicrobial susceptibility test system-short incubation
DEVICE CLASSIFICATION:	Fully Automated Short-Term Incubation CycleAntimicrobial Susceptibility Device, 21 CFR 866.1645
PREDICATE DEVICES:	Sensititre® ESBL confirmatory test plate (K031545) andBD Phoenix™ Automated Microbiology System withGatifloxacin (K020321, May 23, 2002), Ofloxacin(K020323, April 14, 2002), and Levofloxacin (K020322,March 27, 2002).
INTENDED USE:	The BD Phoenix™ Automated Microbiology System isintended for the rapid identification and in vitroantimicrobial susceptibility testing of isolates from pureculture of most aerobic and facultative anaerobic Gram-negative and Gram-positive bacteria of human origin.

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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.

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 the confirmatory ESBL test.

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).

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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 test and associated reagents.

The results of the study demonstrate for the this test 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.

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 test. 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.

Confirmatory ESBL Test Performance

To determine the accuracy of the Phoenix Confirmatory ESBL test, accuracy testing was performed at multiple sites using Clinical and Challenge isolates. The results from the ESBL test resident on the Phoenix panels were compared to the results obtained from the reference confirmatory ESBL test.

For Challenge organisms this result is an expected result and for Clinical isolates this result was obtained from concurrent testing in the NCCLS reference broth microdilution method. Additionally, a challenge set of 30 previously characterized organisms was tested at one site.

Positive Percent Agreement = 183/189 = 96.8% Negative Percent Agreement = 780/812 = 96.1% Overall Percent Agreement = 963/1001 = 96.2%

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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 test is substantially equivalent. Technological characteristics of this system are substantially equivalent to those used in the Sensititre® ESBL confirmatory test plates, which received clearance by the FDA under K031545 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/4/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 stripes forming its body and wing. The eagle is positioned to the right of the text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA", which is arranged in a circular fashion around the left side of the logo.

Public Health Service

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

MAY 2 8 2004

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

K033458 Re: Trade/Device Name: BD Phoenix™ Automated Microbiology System Confirmatory ESBL Test 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: April 6, 2004 Received: April 7, 2004

Dear Ms. Giguere:

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 (sec above) into cither 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), You may obtain other general information on your responsibilities under the Act 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.

Sincercly yours.

Sagahts

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: K033458

Device Name: BD Phoenix™ Automated Microbiology System for use with the confirmatory ESBL Test - Gram-negative ID/AST or AST only Phoenix panels.

Indications for Use:

Prescription Use V (Part 21 CFR 801 Subpart D) AND/OR

Over-the-Counter Use (21 CFR 807 Subpart C)

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

Concurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)

SAKWA

Division Siging

Office of the Millettral Diginostic Device Evaratizitation rath Safety

510(k) $\frac{K03245K}{}$

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.”