(28 days)
The Sensitite Haemophilus / Streptococcus pneumoniae (HP) MIC Susceptibility plate is an in vitro diagnostic product for clinical susceptibility testing of Haemophilus / Streptococcus pneumoniae .
This 510(k) is for the addition of Gemifloxacin in the dilution range of 0.001 - 16 ug/ml to the Sensititre Haemophilus / Streptococcus pneumoniae (HP) MIC Susceptibility plate MIC panel for testing Haemophilus / Streptococcus pneumoniae isolates. The approved primary " Indications for Use" and clinical significance of Gemifloxacin is for: Streptococcus pneumoniae and Haemophilus Influenzae.
Sensititre® Haemophilus/Streptococcus pneumoniae (HP) MIC Plates
This is a 510(k) premarket notification for adding a new antibiotic (Gemifloxacin) to an existing antimicrobial susceptibility test plate for Haemophilus and Streptococcus pneumoniae. The submission focuses on the performance of Gemifloxacin with these specific bacteria.
Here's an analysis of the acceptance criteria and study information provided in the document:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly present a table of acceptance criteria or reported device performance in the typical format of sensitivity, specificity, or AUC. Instead, for antimicrobial susceptibility testing, performance is generally evaluated based on agreement rates between the new device and a reference method (often broth microdilution or agar dilution). The key metrics for this type of test are:
- Essential Agreement (EA): The MIC result from the new device is within plus or minus one two-fold dilution of the reference method MIC.
- Categorical Agreement (CA): The interpretive category (Susceptible, Intermediate, Resistant) from the new device matches the reference method.
- Major Discrepancy (MD): The new device reports Susceptible while the reference reports Resistant.
- Minor Discrepancy (mD): The new device reports Intermediate while the reference reports Susceptible or Resistant, or vice versa.
- Very Major Discrepancy (VMD): The new device reports Resistant while the reference reports Susceptible.
Based on standard FDA guidance for AST devices, the acceptance criteria typically involve high EA and CA, with low percentages of MD and VMD.
While the specific numerical acceptance criteria are not stated in the provided text, the approval implies that the sponsor met FDA's expectations for these metrics. The letter focuses on the administrative aspects of approval, not the detailed study results. To provide a table, I would need more detailed information from the actual 510(k) submission, which is not fully included here.
However, based on typical FDA requirements for AST devices, a hypothetical table would look like this (with specific values usually included in the full submission, but not in this high-level letter):
| Metric | Acceptance Criteria (Typical) | Reported Device Performance (Hypothetical, as not provided) |
|---|---|---|
| Essential Agreement (EA) | ≥ 90% | [Actual % would be here] |
| Categorical Agreement (CA) | ≥ 90% | [Actual % would be here] |
| Major Discrepancy (MD) | ≤ 3% | [Actual % would be here] |
| Minor Discrepancy (mD) | Not usually a limiting factor | [Actual % would be here] |
| Very Major Discrepancy (VMD) | ≤ 1.5% | [Actual % would be here] |
The study described implicitly in the approval process would have demonstrated that the Sensititre® Haemophilus/Streptococcus pneumoniae (HP) MIC Plates, when testing Gemifloxacin, achieved these levels of agreement with a reference method for Haemophilus and Streptococcus pneumoniae isolates.
2. Sample Size Used for the Test Set and the Data Provenance
The provided text does not specify the exact sample size used for the test set or the data provenance (e.g., country of origin, retrospective/prospective).
For AST devices evaluating a new antimicrobial, FDA guidance (e.g., "Guidance for Industry and FDA - Referencing the Clinical and Laboratory Standards Institute Antimicrobial Susceptibility Testing Standards for Device Submissions") typically recommends testing a diverse set of isolates, including those with various resistance mechanisms, and often hundreds of isolates (e.g., >200 for common species, more for less common or resistant phenotypes) across multiple sites. The isolates should be well-characterized.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This information is not provided in the text. For AST, the "ground truth" is typically established by performing the reference method (e.g., CLSI-compliant broth microdilution or agar dilution) by trained microbiologists following standard protocols, not by expert consensus on images or clinical assessments.
4. Adjudication Method for the Test Set
This is not applicable in the context of AST device evaluation for ground truth. The "ground truth" for AST is determined by the reference method's result, not by expert adjudication of discrepancies, although discrepancies between the test device and reference method are analyzed.
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 question is not applicable to this type of device. The Sensititre® Haemophilus/Streptococcus pneumoniae (HP) MIC Plate is an in vitro diagnostic (IVD) device for antimicrobial susceptibility testing, which provides quantitative (MIC) or qualitative (S/I/R) results. It is not an AI-powered diagnostic imaging device that involves human readers interpreting cases with or without AI assistance.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
This question is not directly applicable in the context of this specific IVD. The device itself is designed to produce results (MIC values) based on the growth or inhibition of bacteria in the presence of various concentrations of antibiotics. The interpretation of these results into S/I/R categories is done based on established breakpoints, which can be done automatically or by a human reviewing the MIC data. The "standalone" performance here refers to the accuracy of the device in determining the MIC values compared to the reference method (as discussed in point 1). There isn't an "algorithm only without human-in-the-loop" performance in the sense of AI image analysis.
7. The Type of Ground Truth Used
The ground truth used for evaluating the Sensititre® Haemophilus/Streptococcus pneumoniae (HP) MIC Plates with Gemifloxacin would be the results obtained from a CLSI-compliant (Clinical and Laboratory Standards Institute) reference method, such as broth microdilution or agar dilution. These methods are considered the gold standard for determining MICs of antimicrobials.
8. The Sample Size for the Training Set
The concept of a "training set" in the context of machine learning/AI models is not applicable to this type of IVD device. This device is a phenotypic test system (it measures bacterial growth directly), not a software algorithm that learns from data.
9. How the Ground Truth for the Training Set Was Established
As the concept of a training set is not applicable, this question is also not applicable.
§ 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).