(88 days)
ImmunoCAP Tryptase is an in vitro semi-quantitative assay for measurement of tryptase in human serum or plasma (EDTA, lithium heparin or sodium heparin). It is intended for in vitro diagnostic use as an aid in the clinical diagnosis of patients with a suspicion of systemic mastocytosis in conjunction with other clinical and laboratory findings. ImmunoCAP Tryptase is to be used with the instruments Phadia 100 and Phadia 250.
ImmunoCAP Tryptase reagents are modular in concept and are available individually in different package sizes dependent on instrument system used.
The reagents needed to perform the ImmunoCAP Tryptase assay are listed below. ImmunoCAP Tryptase/ImmunoCAP Tryptase Conjugate 50 (10-9525-02/10-9522-02) ImmunoCAP Tryptase Calibrators/ImmunoCAP Tryptase Calibrator Strip (10-9526-01/10-9523-01) ImmunoCAP Tryptase Curve Control/ImmunoCAP Tryptase Curve Control Strip (10-9527-01/10-9524-01) ImmunoCAP Tryptase Anti-Tryptase (14-4518-01), ImmunoCAP Tryptase Control (10-9370-01)
The Phadia AB ImmunoCAP Tryptase assay is an in vitro semi-quantitative assay for measuring tryptase in human serum or plasma. It is intended for in vitro diagnostic use to aid in the clinical diagnosis of patients suspected of systemic mastocytosis, in conjunction with other clinical and laboratory findings. This submission is an update due to changes in raw materials for the ImmunoCAP Tryptase Conjugate and ImmunoCAP Tryptase Calibrators, but these changes do not affect the intended or indications for use.
1. Acceptance Criteria and Reported Device Performance
The provided document does not explicitly state numerical acceptance criteria in a table format. However, it indicates that the analytical and clinical performance of the updated ImmunoCAP Tryptase was "verified through studies" and concluded to be "substantially equivalent" to the currently cleared product. This implies that the performance in these studies met the thresholds established for substantial equivalence.
The performance characteristics verified include:
- Precision
- Lot-to-lot reproducibility
- Linearity
- Limit of detection
- Hook effect
- Analytical specificity
- Interference of HAMA
- Recovery
- Sample matrix compatibility
- Clinical performance
The document states that "The results showed that the clinical performance of ImmunoCAP Tryptase has not changed when used as an aid in the routine clinical diagnosis of systemic mastocytosis according to WHO criteria."
2. Sample Sizes and Data Provenance
- Test Set Sample Size: The clinical performance was verified through studies performed at two sites, including a total of 138 patients.
- Data Provenance: The document does not explicitly state the country of origin for the clinical samples. The phrase "samples with and without clinical documentation, as well as samples from healthy individuals" suggests a mix, likely from clinical settings where the studies were conducted. It is a prospective clinical evaluation, given the context of verifying performance for a device update.
- Training Set Sample Size: Not explicitly stated. The document describes an update to an existing device rather than a new algorithm development, so a distinct 'training set' for the algorithm in the sense of AI/ML models is not directly applicable here. The focus is on verifying that the material changes do not alter performance.
3. Number and Qualifications of Experts for Ground Truth
Not applicable. This device is a semi-quantitative assay for a biomarker (tryptase), not an imaging or diagnostic AI device requiring expert adjudication of images or clinical cases for ground truth establishment. The ground truth for clinical performance would be the definitive diagnosis of systemic mastocytosis based on WHO criteria, which involves a combination of clinical, laboratory, and histopathological findings.
4. Adjudication Method for the Test Set
Not applicable. As this is not an AI/ML algorithm requiring human interpretation of outputs, there is no adjudication method in the traditional sense for a test set. Clinical diagnosis based on WHO criteria would be the reference.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
Not applicable. This is not a device that involves human readers interpreting diagnostic outputs. It is a laboratory assay.
6. Standalone Performance Study
Yes, a standalone performance study was done for the device. The document details the analytical performance characteristics (precision, linearity, limit of detection, etc.) and states that the updated ImmunoCAP Tryptase was compared to the currently cleared ImmunoCAP Tryptase using samples. This inherently describes a standalone performance evaluation of the updated device.
7. Type of Ground Truth Used
For the clinical performance verification, the ground truth was "routine clinical diagnosis of systemic mastocytosis according to WHO criteria." This indicates a comprehensive set of diagnostic guidelines, which would typically involve expert consensus, clinical symptoms, laboratory markers (including tryptase levels), and potentially bone marrow biopsy results.
For the analytical performance verification, the ground truth would be based on established analytical methods and reference materials to assess accuracy, precision, linearity, etc.
8. Sample Size for the Training Set
Not applicable. This is not an AI/ML algorithm that undergoes a training phase with a specific training set of data. The submission is for an update to an existing in vitro diagnostic assay due to raw material changes.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no training set in the context of an AI/ML model for this device.
§ 866.5760 Tryptase test system.
(a)
Identification. A tryptase test system is a device that aids in the diagnosis of systemic mastocytosis. It is intended for in vitro diagnostic use as an aid in the clinical diagnosis of patients with a suspicion of systemic mastocytosis in conjunction with other clinical and laboratory findings.(b)
Classification. Class II (special controls). The special control is FDA's guideline entitled “Class II Special Controls Guideline: Tryptase Test System as an Aid in the Diagnosis of Systemic Mastocytosis.” For availability of the document, see § 866.1(e).