(30 days)
The CSA Flex® reagent cartridge is an in vitro diagnostic test intended to quantitatively measure cyclosporine A (CSA) in human whole blood for the Dimension® clinical chemistry system. Measurements of CSA are used as an aid in the management of heart, liver, and kidney transplant patients.
The automated Dimension® CSA method uses an immunoassay technique in which free and CSA-bound antibody-enzyme species are separated using magnetic particles. Following separation, the CSA-antibody-enzyme complex is mixed with the substrate. Bgalactosidase catalyzes the hydrolysis of CPRG (chlorophenol red ß-d- galactopyranoside) to produce CPR (chlorophenol red) that absorbs light maximally at 577 nm. The change in absorbance at 577 nm due to the formation of CPR is directly proportional to the amount of CSA in the patient's sample and is measured using a bichromatic (577, 700 nm) rate technique.
The provided text describes the summary of safety and effectiveness information for the Dade Behring Inc. Cyclosporine (CSA) Flex® reagent cartridge. It primarily focuses on demonstrating substantial equivalence to a predicate device. Here's a breakdown of the requested information:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state "acceptance criteria" in a typical quantitative framework (e.g., "correlation coefficient must be > 0.90"). Instead, it presents a comparison to a predicate device and then reports the performance of the new device against that predicate, implying that the reported values met the implicit criteria for substantial equivalence.
| Acceptance Criteria (Implied by Predicate Comparison) | Reported Device Performance (CSA Flex® vs. Abbott TDx® CSA) |
|---|---|
| Good correlation coefficient | 0.957 |
| Acceptable slope | 0.83 (Note: "Comparative method slope results were expected due to metabolite cross-reactivity differences," implying this value was acceptable despite not being closer to 1) |
| Acceptable intercept | -20.7 ng/mL [-18.6 nmol/L] |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: 667 clinical patient samples
- Data Provenance: The data is described as "clinical patient samples," suggesting it's from human subjects. The country of origin is not specified but is implicitly within the region where Dade Behring Inc. operates (Newark, DE, USA). The study appears to be retrospective in nature as it involved collecting and testing existing clinical samples to compare the two methods.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not explicitly mention the use of experts to establish ground truth for this specific comparison study. The comparison is between two quantitative diagnostic assays (the investigational device, CSA Flex®, and the predicate device, Abbott TDx® CSA). In such cases, the "ground truth" for the comparison is typically the result from the established predicate method or a reference method.
4. Adjudication Method for the Test Set
Not applicable. This was a direct comparison study between two quantitative methods, not a study requiring expert adjudication of qualitative interpretations.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of Human Readers' Improvement with AI vs. Without AI Assistance
Not applicable. This is an in vitro diagnostic device for quantitative measurement of cyclosporine A, not an imaging or diagnostic interpretation device that involves human readers or AI assistance in interpretation.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the study described is a standalone performance comparison. The CSA Flex® reagent cartridge on the Dimension® clinical chemistry system is a device that provides quantitative measurements. The comparison was directly between the quantitative results of the CSA Flex® and the predicate TDx® CSA assay, without human intervention in the result generation or interpretation that would change the quantitative output.
7. The Type of Ground Truth Used
The ground truth used for this comparison study was the results obtained from the predicate device, the Abbott TDx® Cyclosporine Monoclonal Whole Blood Assay. The study essentially compared the new device's performance against an established and legally marketed device.
8. The Sample Size for the Training Set
The document does not specify a separate "training set" for the CSA Flex® reagent cartridge. This type of FDA submission (510(k) for an in vitro diagnostic assay) typically focuses on performance validation rather than machine learning model training as understood in AI/ML contexts. The device's development would involve internal validation and optimization, but distinct "training set" reporting as might be found for AI models is not present here.
9. How the Ground Truth for the Training Set Was Established
As no specific "training set" is mentioned in the context of machine learning for this device, the method for establishing its ground truth is not detailed. For chemical assays, the development process generally involves optimizing reagents and protocols against known standards and reference materials, rather than a labeled training dataset of patient samples.
§ 862.1235 Cyclosporine test system.
(a)
Identification. A cyclosporine test system is a device intended to quantitatively determine cyclosporine concentrations as an aid in the management of transplant patients receiving therapy with this drug. This generic type of device includes immunoassays and chromatographic assays for cyclosporine.(b)
Classification. Class II (special controls). The special control is “Class II Special Controls Guidance Document: Cyclosporine and Tacrolimus Assays; Guidance for Industry and FDA.” See § 862.1(d) for the availability of this guidance document.