(45 days)
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-Enteriaceae 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 rifampin at concentrations of 0.25-32 ug/mL to Gram Positive ID/AST or AST only Phoenix panels. Rifampin 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:
Staphylococcus aureus (including Methicillin-Resistant/MRSA)
Staphylococcus epidermidis
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).
Here's a breakdown of the acceptance criteria and study information for the BD Phoenix™ Automated Microbiology System (Rifampin 0.25-32 µg/mL), based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implied by the reported performance (Essential Agreement (EA) and Category Agreement (CA)) and the statement that the system demonstrated "substantially equivalent performance" compared to the NCCLS reference method as outlined in the FDA guidance document. While specific thresholds for EA and CA are not explicitly stated as "acceptance criteria" in a numerical table, the reported values indicate successful performance.
| Performance Metric | Acceptance Criteria (Implied by FDA Guidance) | Reported Device Performance (Rifampin) |
|---|---|---|
| Essential Agreement (EA) | Substantially equivalent to NCCLS reference method (typically acceptable if high agreement) | 98.3% (n=1261) |
| Category Agreement (CA) | Substantially equivalent to NCCLS reference method (typically acceptable if high agreement) | 98.2% (n=1261) |
| Intra-site Reproducibility | Greater than 90% | Greater than 90% |
| Inter-site Reproducibility | Greater than 95% | Greater than 95% |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: 1261 isolates were used for the clinical studies comparing Phoenix System results to reference methods for Rifampin. This sample size (n=1261) is specifically for the EA and CA percentages reported for Rifampin.
- Data Provenance: The isolates were "Clinical, stock and challenge isolates" tested "across multiple geographically diverse sites across the United States." This indicates a prospective and multi-center data collection approach.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not specify the number or qualifications of experts used to establish the ground truth.
4. Adjudication Method for the Test Set
The document does not specify an adjudication method like 2+1 or 3+1. The ground truth for clinical isolates was established by the "NCCLS reference broth microdilution method." For challenge set isolates, it was compared to "expected results."
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
This is not an AI-assisted device for human interpretation; it is an automated microbiology system that provides direct results (MIC values and category interpretations). Therefore, an MRMC study comparing human readers with and without AI assistance is not applicable and was not performed.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done
Yes, a standalone performance evaluation was conducted. The BD Phoenix™ Automated Microbiology System operates as an automated system, generating results (ID, MIC, S/I/R categories) directly based on its internal algorithms and biochemical/turbidity readings. Its performance (EA and CA) was compared directly to a "reference method" (NCCLS broth microdilution), which represents its standalone accuracy.
7. The Type of Ground Truth Used
- For clinical isolates: The ground truth was established by the NCCLS reference broth microdilution method. This is a well-established and standardized laboratory method considered the gold standard for antimicrobial susceptibility testing.
- For challenge set isolates: The ground truth was based on "expected results."
8. The Sample Size for the Training Set
The document does not specify a sample size for a training set. This is typical for traditional (non-AI/machine learning) automated systems, where the "training" consists of developing and validating the underlying algorithms and biochemical reactions rather than training a machine learning model on a distinct dataset.
9. How the Ground Truth for the Training Set Was Established
Since there is no explicit mention of a "training set" in the context of machine learning, the concept of establishing ground truth for it is not applicable here. The fundamental principles and "ground truth" for the system's operation would be derived from general microbiological principles and extensive laboratory testing during the development of the assay and instrument.
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CONFIDENTIAL AND PROPRIETARY
510(k) SUMMARY
| SUBMITTED BY: | Becton, Dickinson and Company7 Loveton CircleSparks, MD 21152Phone: 410-316-4260Fax: 410-316-4499 | JAN 31 2003 |
|---|---|---|
| CONTACT NAME: | Kathryn Babka Powers,Regulatory Affairs Specialist | |
| DATE PREPARED: | December 16, 2002 | |
| DEVICE TRADE NAME: | BD Phoenix™ Automated Microbiology System –Rifampin 0.25-32 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 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.
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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).
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.
Table 1: Performance of BD Phoenix System for Gram-Positive Organisms by Drug
| Antimicrobial | Concentration | EA (n) | EA (%) | CA (n) | CA (%) |
|---|---|---|---|---|---|
| Rifampin | 0.25-32 µg/mL | 1261 | 98.3 | 1261 | 98.2 |
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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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 circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is an abstract symbol that resembles three human profiles facing right, with flowing lines beneath them.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
JAN 3 1 2003
Ms. Kathryn Babka Powers Regulatory Affairs Specialist BD Diagnostics Systems Becton, Dickinson and Company 7 Loveton Circle Sparks, MD 21152
K024152 Re: Trade/Device Name: BD Phoenix™ Automated Microbiology System Rifampin (0.25-32 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: December 16, 2002 Received: December 17, 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 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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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 Sutman
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: K024152
Device Name: BD Phoenix™ Automated Microbiology System for use with the antimicrobial agent Rifampin (0.25-32 ug/mL) - 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 antimicrobial susceptibility by minimal inhibitory concentration (MIC) of most Gram-negative aerobic and facultative anaerobic bacteria isolates from pure culture for Enterobacteriaceae and Non-Enteriaceae 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 rifampin at concentrations of 0.25-32 ug/mL to Gram Positive ID/AST or AST only Phoenix panels. Rifampin has been shown to be active in vitro against most strains of microorganisms listed below, as described in the FDAapproved package insert for this antimicrobial agent.
Active In Vitro Against:
Staphylococcus aureus (including Methicillin-Resistant/MRSA) Staphylococcus epidermidis
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Ferdin Poole
(Division Sian-Off Division of Clinica: Laboratory Devices
510(k) Number K024152
Prescription Use
(Per 21 CFR 801.109)
§ 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.”