(28 days)
VITEK® 2 Yeast Micafungin is designed for antifungal susceptibility testing of Candida species. VITEK® 2 Yeast Micafungin is a quantitative test intended for use with the VITEK® 2 COMPACT Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. VITEK® 2 Yeast Micafungin has been shown to be active against most isolates of the microorganisms listed below, according to the FDA label for this antifungal.
Active in vitro and clinical infections:
- Candida albicans
- Candida glabrata Candida guilliermondii
- Candida krusei
- Candida parapsilosis
- Candida tropicalis
The VITEK @ 2 Antimicrobial Susceptibility Test (AST) is intended to be used with the VITEK® 2 Systems for the automated quantitative or qualitative susceptibility testing of isolated colonies for the most clinically significant aerobic gram-negative bacilli, Staphylococcus spp., Enterococcus spp., Streptococcus spp., S. pneumoniae, and clinically significant yeast.
VITEK® 2 Yeast Micafungin is designed for antifungal susceptibility testing of Candida species. VITEK® 2 Yeast Micafungin is a quantitative test intended for use with the VITEK® 2 and VITEK® 2 COMPACT Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial aqents.
The provided text describes a Special 510(k) Device Modification for the VITEK 2 AST-YS Micafungin, which involves changing the expected Quality Control (QC) range for the QC organism C. parapsilosis ATCC 22019. It focuses on the regulatory approval process rather than a detailed study comparing device performance against acceptance criteria in a clinical setting for diagnostic accuracy.
Therefore, many of the requested elements for describing "acceptance criteria and the study that proves the device meets the acceptance criteria" in terms of algorithm performance or clinical utility are not applicable or not provided in this document. The focus of this document is a modification to a QC range, which ensures the reliability of the test itself, not its diagnostic accuracy in patients.
Here's a breakdown of the available information:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Original QC Range) | Reported Device Performance (New QC Range) | Notes |
|---|---|---|
| Expected QC range for C. parapsilosis ATCC 22019: 0.5-2 µg/mL | Expected QC range for C. parapsilosis ATCC 22019: 0.25-1 µg/mL | This is a modification to the acceptance criteria (specifically, the QC range) based on a CLSI M23 study. The validation for this new range demonstrated "acceptable performance during risk assessment validation studies." The document does not provide specific performance metrics (e.g., accuracy, sensitivity, specificity, or reproducibility rates) against these ranges. |
2. Sample size used for the test set and the data provenance:
- Sample size: Not specified. The document mentions a "completed CLSI M23 study" but does not provide details on the number of isolates or replicates used in this study to establish the new QC range.
- Data provenance: Not specified (e.g., country of origin, retrospective or prospective).
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not Applicable. This document concerns a change in a QC range for an Antimicrobial Susceptibility Test (AST) device, not a diagnostic device where expert ground truth on patient samples would typically be established. The "ground truth" here is the established and validated range for a specific QC organism based on a standardized protocol (CLSI M23).
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not Applicable. Adjudication methods are typically used in clinical studies involving interpretation of images or other subjective data by multiple readers. This document describes a QC range modification for an automated AST device, which relies on objective measurements.
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:
- Not Applicable. This is not an AI-assisted diagnostic device, nor does it involve human readers interpreting results in a MRMC study context.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Partially Applicable. The VITEK 2 system is an automated AST device. The "algorithm" here refers to the system's ability to accurately determine susceptibility based on its internal processes and calibrated ranges. The document states that "Validation of the modified QC range and QC performance with the modified range has now been established," implying standalone performance verification for the device with the new QC range. However, no specific performance metrics (e.g., categorical agreement, essential agreement) of this standalone performance are provided in this summary.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" for establishing the QC range is derived from standardized laboratory testing protocols (CLSI M23) using a reference QC organism (C. parapsilosis ATCC 22019). This involves multiple replications of testing under controlled conditions to determine the consistent susceptibility range of the QC organism to the antimicrobial agent (micafungin).
8. The sample size for the training set:
- Not Applicable / Not Provided. This document does not pertain to an algorithm that requires a "training set" in the context of machine learning or AI. The CLSI M23 study would involve a study set to establish the new range, but it's not a "training set" in the computational sense. The size of this study set is not specified.
9. How the ground truth for the training set was established:
- Not Applicable / Not Provided. As noted above, there's no "training set" in the computational sense. The "ground truth" for the QC range was established through a "completed CLSI M23 study" which provides a standardized methodology for determining acceptable QC ranges for AST devices.
In summary, this regulatory submission focuses on a modification to an existing device's quality control parameters, rather than a de novo clinical validation study of a diagnostic device's accuracy. The "study" mentioned is a "CLSI M23 study" that established a new expected QC range for a specific organism.
§ 866.1640 Antimicrobial susceptibility test powder.
(a)
Identification. An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases.(b)
Classification. Class II (performance standards).