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.

This premarket notification is for the addition of the antimicrobial agent cefepime at concentrations of 0.0625-4 ug/mL to Streptococcus ID/AST or AST only Phoenix panels. Cefepime has been shown to be active in virro against most strains of microorganisms listed below, as described in the FDA-approved package insert for this antimicrobial agent.

Active In Vitro and in Clinical Infections Against:

Streptococcus pneumoniae
Streptococcus pyogenes (Lancefield's Group A streptococci)
Viridans group streptococci

Active In Vitro Against:

Streptococcus agalactiae (Lancefield's Group B streptococci)

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. For testing Streptococcus species 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-S Broth used for performing AST tests only. .
BD Phoenix AST-S 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°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, R or N (susceptible, intermediate, resistant or not susceptible).

AI/ML Overview

Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:

Device: BD Phoenix™ Automated Microbiology System - Cefepime 0.0625-4 µg/mL

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Required Performance)	Reported Device Performance (Cefepime 0.0625-4 µg/mL)
Site Reproducibility:
Overall Intra-site Reproducibility > 90%	> 90%
Overall Inter-site Reproducibility > 95%	> 95%
Clinical Performance:
Essential Agreement (EA) with reference	97.7% (n=1890)
Category Agreement (CA) with reference	94.3% (n=1890)

Note: The document implicitly defines these performance metrics as the acceptance criteria by stating that the system demonstrated "substantially equivalent performance" by meeting these figures when compared to the CLSI reference method, as outlined in the FDA draft guidance document.

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

Test Set Sample Size (n): 1890 isolates. This refers to the combined number of clinical, stock, and challenge isolates used for the Essential Agreement (EA) and Category Agreement (CA) calculations for Cefepime.
Data Provenance: The data was collected from "multiple geographically diverse sites across the United States." The isolates included:
- Clinical isolates: Used for comparison to the CLSI reference broth microdilution method.
- Stock isolates: Not explicitly detailed how they were used, but implied in the overall "isolates tested."
- Challenge isolates: Compared to "expected results."
- The study is prospective in nature as it details performance testing of the device against reference methods.

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

The document does not explicitly state the number of experts or their qualifications for establishing the ground truth.

However, the ground truth was established by:

CLSI reference broth microdilution method: This is a standardized laboratory method, and the interpretation would typically be performed by trained microbiologists or laboratory personnel following CLSI guidelines. The expertise lies in adherence to a standardized protocol rather than individual experts' subjective assessment.
"Expected results" for Challenge set isolates: This implies pre-established results for a known set of organisms, likely determined by expert consensus or established reference methods prior to the study.

4. Adjudication Method for the Test Set

The document does not explicitly describe an adjudication method (e.g., 2+1, 3+1).

The primary comparison was between the BD Phoenix™ System results and established reference methods (CLSI reference broth microdilution or "expected results" for challenge isolates). Discrepancies would likely be analyzed based on the defined agreement criteria (EA and CA) rather than through a separate expert adjudication process for each individual case.

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

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done.

This type of study typically involves multiple human readers interpreting cases with and without AI assistance to measure the effect size of AI on human performance. The BD Phoenix™ Automated Microbiology System is an automated device designed to perform antimicrobial susceptibility testing; it does not involve human readers in the interpretation process in the way medical imaging AI might. The comparison here is between the automated system's output and a reference laboratory method.

6. Standalone Performance

Yes, a standalone performance study was done.

The entire study described is a standalone performance evaluation of the BD Phoenix™ Automated Microbiology System. It evaluates the algorithm's (device's) ability to correctly determine MIC values and categorical interpretations (S, I, R, N) without human intervention in the interpretation flow. The results (EA and CA percentages) directly reflect the algorithm-only performance against a reference standard.

7. Type of Ground Truth Used

The primary ground truth used was:

Reference Standard Data:
- CLSI (Clinical and Laboratory Standards Institute) reference broth microdilution method: This is a widely accepted laboratory standard for antimicrobial susceptibility testing.
- "Expected results" for Challenge set isolates: These represent predetermined or known results for a panel of bacterial isolates, likely established through extensive testing with reference methods or expert consensus.

8. Sample Size for the Training Set

The document does not provide information regarding the sample size for the training set. This information is typically proprietary to the manufacturer and not usually included in 510(k) summaries, which focus on validation studies for regulatory approval.

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

The document does not provide information on how the ground truth for the training set was established, as it does not discuss the training process of the device.

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 GiguereRegulatory Affairs Speicalist
DATE PREPARED:	May 9, 2005
DEVICE TRADE NAME:	BD Phoenix™ Automated Microbiology System -Cefepime 0.0625-4 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 (K020321May 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 . or AST determinations.
BD Phoenix ID Broth used for performing ID tests and preparing AST Broth inoculum. .
BD Phoenix AST-S Broth used for performing AST tests only. .
BD Phoenix AST-S 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 CLSI reference broth microdilution method. This premarket notification provides data supporting the use of the BD Phoenix™ Automated Microbiology System Streptococcus 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 CLSI reference broth microdilution method (AST panels prepared according to NCCLS M7). The system has been eyaluated as defined in the FDA Draft guidance document, "Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA," February 5, 2003.

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 streptoccal isolates. Each site tested the isolates in triplicate on three different days using one lot of Streptococcus 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 streptococcal 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 Streptococcus 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 CLSI 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 PhoenixTM Automated Microbiology System agrees with the reference method with respect to the FDA categorical interpretive criteria (susceptible, intermediate, resistant or nonsusceptible).

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

Table 1: Performance of BD Phoenix System for Streptococcal Organisms by Drug

Antimicrobial	Concentration	EA (n)	EA (%)	CA (n)	CA (%)
Cefepime	0.0625-4 μg/mL	1890	97.7	1890	94.3

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, "Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA," February 5, 2003. 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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Image /page/3/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized depiction of an eagle with three lines forming its body and wings. The eagle faces right and is positioned within a circle. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" is arranged around the upper portion of the circle.

JUN 2 4 2005

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

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

K051204 Re:

Trade/Device Name: BD Phoenix™ Automated Microbiology System Cefepime (0.0625-4 µg/mL) - Streptococcus ID/AST or AST 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: May 9, 2005 Received: May 11, 2005

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 for associated in the 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 r ou may, utcher sever 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) I his letter witi anow you to oogin manies.ing , a substantial equivalence of your device to a legally premarket normodion: "The sults 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 (c.v. If you desire specific intornialion as advertising of your device, please contact the Office of In of questions on the promotion and Safety at (240)276-0484. Also, please note the Pill o Daglessio Dorros Londing by reference to premarket notification" (21 CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the r ou may other built butter generational 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/industry/support/index.html

Sincerely yours,

Sales, a Horr

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: Ko51204

Device Name: BD Phoenix™ Automated Microbiology System for use with the antimicrobial agent cefepine (0.0625-4 ug/mL) - Streptococcus ID/AST or AST only Phoenix Panels.

Indications for Use:

The BD Phoenix™ Automated Microbiology System is intended for in vitro quantitative determination of 1 110 DD Invenue entibility by minimal inhibitory concentration (MIC) of most Gram-negative aerobic and annitative 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 , Enterococcus, and Streptococcus.

Active In Vitro and in Clinical Infections Against:

Streptococcus pneumoniae Streptococcus pyogenes (Lancefield's Group A streptococci) Viridans group streptococci

Active In Vitro Against:

Streptococcus agalactiae (Lancefield's Group B streptococci)

Prescription Use (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 In Vitro Diagnostic Devices (OIVD)

Luddiate Poole

Division Sign-O

BD Diagnostic Systems Becton, Dickinson and Company Office of In Vitro Diagnostic Device

510(k) K051204

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.”