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 grampositive 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 Gentamicin at concentrations of 0.25 - 16 ug/mL to Gram Positive ID/AST or AST only Phoenix panels. Gentamicin 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.

Active In Vitro Against:

Aerobic Gram-positive microorganisms Staphylococcus aureus Coagulase-negative staphylococci

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 ● or 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, focusing on the acceptance criteria and the study that proves the device meets them:

Acceptance Criteria and Device Performance for BD Phoenix™ Automated Microbiology System Gentamicin-GP

1. Table of Acceptance Criteria and Reported Device Performance

The core performance metrics for this device are Essential Agreement (EA) and Category Agreement (CA). The study aimed to demonstrate "substantially equivalent performance" to the NCCLS reference broth microdilution method.

Metric	Acceptance Criteria (Implied by FDA Guidance)	Reported Device Performance
Essential Agreement (EA)	Not explicitly stated but generally expected to be high (e.g., >90%) for substantial equivalence in AST devices.	91.9% (n=1223)
Category Agreement (CA)	Not explicitly stated but generally expected to be high (e.g., >90-95%) for substantial equivalence in AST devices.	95.2% (n=1223)
Intra-site Reproducibility	>90%	>90%
Inter-site Reproducibility	>95%	>95%

Note on Acceptance Criteria: The document refers to the "FDA Draft guidance document, 'Guidance on Review Criteria for Assessment of Antimicrobial Susceptibility Devices', March 8, 2000." While specific numerical acceptance criteria (e.g., 90% for EA, 95% for CA) are not explicitly printed within this 510(k) summary, these are standard expectations for demonstrating substantial equivalence for AST devices based on FDA guidance at that time. The document's statement of "substantially equivalent performance" after reporting these percentages implies these were the thresholds met.

2. Sample Sizes and Data Provenance

Test Set Sample Size: 1223 isolates (reported as 'n' for both EA and CA). This includes clinical, stock, and challenge isolates.
Data Provenance: The isolates were tested "across multiple geographically diverse sites across the United States." The data is prospective for clinical isolates compared to a reference method, and a challenge/stock set was likely retrospective in selection but prospectively tested against the new device.

3. Number of Experts and Qualifications for Ground Truth

The document does not explicitly state the "number of experts" or their "qualifications" in the context of establishing ground truth for the test set.

However, the ground truth was established by:

The NCCLS reference broth microdilution method for clinical isolates. This is a standardized, well-defined laboratory method, implying trained microbiologists/technicians performed these tests.
"Expected results" for challenge set isolates. These "expected results" would have been pre-determined by experts following established protocols, but the specific number or qualifications are not provided here.

4. Adjudication Method for the Test Set

No explicit adjudication method (e.g., 2+1, 3+1) is described for the test set. The comparison for clinical isolates was directly against the NCCLS reference method. For challenge isolates, it was against "expected results."

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No MRMC comparative effectiveness study was mentioned. This device is an automated system for antimicrobial susceptibility testing, not an imaging or diagnostic AI tool that assists human readers. Therefore, the concept of "human readers improve with AI vs without AI assistance" does not directly apply here.

6. Standalone (Algorithm Only) Performance Study

Yes, a standalone study was performed. The BD Phoenix™ Automated Microbiology System is an automated device, and its performance was assessed independently by comparing its results against the NCCLS reference method and expected results for challenge isolates. The reported EA and CA percentages represent this standalone capability.

7. Type of Ground Truth Used

Clinical Isolates: The ground truth was established by the NCCLS reference broth microdilution method. This is a well-accepted laboratory standard for antimicrobial susceptibility testing.
Challenge Isolates: The ground truth was established by "expected results," which are typically pre-determined and validated results for specific strains.

8. Sample Size for the Training Set

The document does not provide a sample size for a training set. This is a 510(k) premarket notification for an automated microbiology system more akin to a laboratory instrument, not a machine learning algorithm that undergoes explicit 'training' in the conventional sense detailed for modern AI devices. The system's rules and algorithms would have been developed and validated internally, likely using various bacterial strains and antimicrobial concentrations during its engineering phase, but this process is not detailed here as "training data" in the AI sense.

9. How Ground Truth for the Training Set Was Established

As mentioned above, the concept of a separate "training set" with ground truth in the AI context isn't explicitly addressed. The system's internal mechanisms for determining MIC values and categorical interpretations would have been developed based on established microbiological principles, extensive internal testing, and alignment with breakpoints defined by regulatory bodies (like FDA) and standards organizations (like NCCLS). These foundational data and principles would have informed the system's development, but a distinct "training set" for an AI model is not described.

Summary

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OCT 31 2002

BD PHOENIX™ Automated Microbiology System Gentafhicin-GP

CONFIDENTIAL AND PROPRIETARY

510(k) SUMMARY

Y623273

SUBMITTED BY: Becton, Dickinson and Company 7 Loveton Circle Sparks, MD 21152 Phone: 410-316-4287 410-316-4499 Fax: Kathryn Babka Powers, CONTACT NAME: Regulatory Affairs Specialist

DATE PREPARED:

DEVICE TRADE NAME:

Antimicrobial susceptibility test system-short incubation DEVICE COMMON NAME:

Gentamicin 0.25 - 16 ug/mL

September 30, 2002

Fully Automated Short-Term Incubation Cycle Antimicrobial DEVICE CLASSIFICATION: Susceptibility Device, 21 CFR 866.1645

BD Phoenix™ Automated Microbiology System -

VITEK® System (PMA No. N50510) and BD Phoenix™ PREDICATE DEVICES: Automated Microbiology System with Gatifloxacin (K020321, May 23, 2002), Ofloxacin (K020323, April 14, 2002), and Levofloxacin (K020322, March 27, 2002).

The BD Phoenix™ Automated Microbiology System is INTENDED USE: 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 grampositive bacteria of human origin.

DEVICE DESCRIPTION:

BD Phoenix instrument and software. ●
BD Phoenix panels containing biochemicals for organism ID testing and antimicrobial agents ● or 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 positive 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-positive isolates. Each site tested the isolates in triplicate on 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 reproducibility of greater than 90% and 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 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.

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

Antimicrobial	Concentration	EA (n)	EA (%)	CA (n)	CA (%)
Gentamicin	0.25 - 16 μg/mL	1223	91.9	1223	95.2

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 a black and white logo. The logo is a circular seal with text around the perimeter. Inside the circle is a stylized image of three human profiles facing to the right. The profiles are stacked on top of each other, with the top profile being the largest and the bottom profile being the smallest.

OCT 31 2002

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Ms. Kathryn Babka Powers Regulatory Affairs Specialist BD Diagnostic Systems Becton, Dickinson and Company 7 Loveton Circle Sparks. MD 21152

K023273 Re:

Trade/Device Name: BD Phoenix™ Automated Microbiology Systems,

Gentamicin (0.25-16 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: September 30, 2002 Received: October 1, 2002

Dear Ms. Powers:

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 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.

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); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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This letter will allow you to begin marketing your device as described in your 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 advice for your device on our labeling regulation (21 CFR Part 801 and 1 additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR 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/cdrlvdsma/dsmamain.html".

Sincerely yours,

Steven Butman

Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Page 1 of 1

KD2 3273 510(k) Number:

Device Name: BD Phoenix™ Automated Microbiology System for use with the antimicrobial agent Gentamicin (0.25 - 16 ug/mL) - Gram positive ID/AST or AST only Phoenix panels.

Indications for Use: .

Active In Vitro Against:

Aerobic Gram-positive microorganisms Staphylococcus aureus Coagulase-negative staphylococci

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Freddie Poole

(Division Sign-Off) Division of Clinical Laboratory Devices

510(k) Number K023273

Prescription Use (Per 21 CFR 801.109)

Page 9

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.”