(44 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-Enterobacteriaceae and most Gram-positive bacteria isolates from pure culture belonging to the genera Staphylococcus and Enterococcus.
This premarket notification is for the antimicrobial agent amoxicillin-clavulanate at concentrations of 0.25/0.12-32/16 ug/mL to Gram-positive ID/AST or AST only Phoenix panels. Amoxicillin-clavulanate 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 and in Clinical Infections Against:
Staphylococcus aureus (beta-lactamase and non-beta-lactamase producing)
Active In Vitro Against:
Enterococcus faccalis
Staphylococccus epidermidis (beta-lactamase and non-beta-lactamase producing)
Staphylococcus saprophyticus (beta-lactamase and non-beta-lactamase producing)
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. Phoenix panels are inoculated with a specified organism density and placed into the instrument.
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).
Here's an analysis of the provided 510(k) summary regarding the BD Phoenix™ Automated Microbiology System for Amoxicillin-clavulanate, structured according to your requested information.
1. A table of acceptance criteria and the reported device performance
| Performance Metric | Acceptance Criteria (Implicit from FDA Guidance) | Reported Device Performance |
|---|---|---|
| Essential Agreement (EA) | Generally > 90% | 94.1% |
| Category Agreement (CA) | Generally > 90% | 96.7% |
| Reproducibility | Generally > 90% | Intra-site: > 90% |
| Inter-site: > 95% |
Note: The acceptance criteria are "generally >90%" for these types of devices based on the referenced FDA Draft guidance document, "Guidance on Review Criteria for Assessment of Antimicrobial Susceptibility Devices", March 8, 2000. Specific numerical thresholds are not explicitly stated as "acceptance criteria" in the document, but rather performance demonstrated to be "substantially equivalent."
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Test Set Sample Size: 871 isolates (combined clinical, stock, and challenge isolates).
- Data Provenance:
- Country of Origin: United States ("multiple geographically diverse sites across the United States").
- Retrospective/Prospective: Not explicitly stated, but the mention of "clinical, stock and challenge isolates" being tested and clinical isolates being compared to a reference method suggests a blend. "Clinical isolates" would likely be prospective or recently collected if they were concurrently tested with the reference method. "Stock and challenge isolates" are typically existing, well-characterized collections.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
- The document does not mention the use of human experts to establish ground truth for the test set.
- Instead, the ground truth for clinical isolates was established by comparison to a CLSI reference broth microdilution method.
- For challenge isolates, it was compared to "expected results," which typically refers to established and validated results for those specific strains.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- There was no mention of an adjudication method involving human experts for the test set.
- The comparison was directly between the BD Phoenix System's results and the reference method or 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
- No, an MRMC comparative effectiveness study was not done. This study assesses the performance of an automated system (BD Phoenix) against a reference laboratory method, not the improvement of human readers with or without AI assistance. The BD Phoenix is a standalone automated susceptibility test system.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Yes, a standalone study was done. The entire study presented is a standalone performance assessment of the BD Phoenix™ Automated Microbiology System (device/algorithm only) compared to the CLSI reference broth microdilution method without human intervention during the interpretation phase by the device. The device itself interprets the readings to determine MIC values and category interpretations.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Clinical Isolates: The ground truth was established by the CLSI reference broth microdilution method. The CLSI (Clinical and Laboratory Standards Institute) method is a standardized, well-accepted laboratory procedure considered the gold standard for antimicrobial susceptibility testing.
- Challenge Isolates: The ground truth was based on "expected results" for these characterized strains.
8. The sample size for the training set
- The document does not provide information on the sample size for the training set. The 510(k) summary focuses on the validation of the device's performance, not its development or training data.
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 phase of the device.
§ 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.”