(285 days)
Spectrolyse ® PAI-1 kit, Product # 101201, is intended for the quantitative determination of Plasminogen Activator Inhibitor Type-1 (PAI-1) activity in human plasma. The test is for in vitro diagnostic use and is not intended for internal use in humans and animals.
Spectrolyse @ PAI-1 is a two stage colorimetric assay. The first stage involves incubating samples with a known amount of tPA, allowing PAI-1 in the sample to react with tPA. In the second stage, the residual tPA activity converts plasminogen to plasmin, which in turn hydrolyzes a plasmin chromogenic substrate, SPECTROZYME® PL. PAI-1 in the plasma is determined as the difference between the amount of tPA added and the amount of tPA recovered.
Analysis of Spectrolyse® PAI-1 Device Performance
This document describes the acceptance criteria and the supporting study for the Spectrolyse® PAI-1 Quantitative Factor Deficiency Test (Product #101201).
1. Table of Acceptance Criteria and Reported Device Performance
The device sought substantial equivalence to a predicate device in terms of performance and intended use. The primary performance metric evaluated was the correlation with the predicate device. Precision (intra-assay and inter-assay variability) was also assessed.
| Performance Metric | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Correlation | Positive correlation (R value close to 1, slope close to 1, intercept close to 0) with the predicate device. | Study 1: N=34, Regression Equation: Y=1.0787X+-4.76, R=0.953, Sy.x=3.31 ng/ml (Sample Range: 5.3-37.8 ng/ml) |
| Study 2: N=34, Regression Equation: Y=1.0179X+-3.75, R=0.955, Sy.x=2.65 ng/ml (Sample Range: 5.0-42.3 ng/ml) | ||
| Precision | Low intra-assay and inter-assay Coefficients of Variation (CV%) for control samples. | Study #1: |
| Control 1 (Mean 10.4 IU/mL): Intra-Assay CV% = 3.6%, Inter-Assay CV% = 12.9% | ||
| Control 2 (Mean 13.8 IU/mL): Intra-Assay CV% = 3.4%, Inter-Assay CV% = 7.5% | ||
| Control 3 (Mean 22.2 IU/mL): Intra-Assay CV% = 2.4%, Inter-Assay CV% = 3.9% | ||
| Study #2: | ||
| Control 1 (Mean 6.7 IU/mL): Intra-Assay CV% = 14.4%, Inter-Assay CV% = 10.2% | ||
| Control 2 (Mean 14.4 IU/mL): Intra-Assay CV% = 3.5%, Inter-Assay CV% = 5.7% | ||
| Control 3 (Mean 26.0 IU/mL): Intra-Assay CV% = 2.0%, Inter-Assay CV% = 4.1% |
Note: The document implies acceptance criteria by stating that the device is "substantially equivalent" to a predicate device based on these performance metrics. Specific numerical cut-offs for R, slope, intercept, and CV% are not explicitly provided as 'acceptance criteria' in the text, but the reported values support the claim of substantial equivalence.
2. Sample Size and Data Provenance for the Test Set
- Sample Size for Test Set:
- Method Comparison Studies: 34 samples per study. (Total of 68 unique samples if the two studies used different sets, or 34 if they used the same samples analyzed with two different lots). The text states "two lots of Spectrolyse® PAI-1" were used across "two method comparison studies," suggesting that each study potentially involved the same set of 34 samples tested with a different lot, or two distinct sets of 34 samples.
- Precision Studies: Not applicable to patient samples for ground truth. Control samples (3 different concentrations) were used. In Study #1, controls were run in replicates of 4 over 20 runs (N=40 per control). In Study #2, controls were run in replicates of 4 over 5 runs (N=10 per control).
- Data Provenance: The document does not explicitly state the country of origin of the data or whether it was retrospective or prospective. Given the context of a 510(k) submission for an in vitro diagnostic, it is generally assumed to be prospective or recent retrospective data collected typically in a clinical laboratory setting, likely within the US, but this is not confirmed.
3. Number of Experts and Qualifications for Ground Truth
- Number of Experts: Not applicable. For quantitative diagnostic tests like this, 'ground truth' for patient samples is established by comparison to a reference method (the predicate device) or a gold standard assay, not by expert consensus on visual interpretation or clinical judgment.
- Qualifications of Experts: Not applicable.
4. Adjudication Method for the Test Set
- Adjudication Method: Not applicable. The "ground truth" for method comparison was the result obtained from the predicate device, which is an established quantitative assay. There was no need for expert adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Was an MRMC study done? No. This device is a quantitative in vitro diagnostic (IVD) assay designed to measure a specific analyte (PAI-1 activity) in human plasma. It does not involve human readers interpreting images or data in a way that would necessitate an MRMC comparative effectiveness study to assess improvement with AI assistance. The device operates independently of human interpretive input in its primary function.
6. Standalone Performance Study
- Was a standalone study done? Yes. The entire submission focuses on the standalone performance of the Spectrolyse® PAI-1 device. The method comparison studies directly compare the performance of the Spectrolyse® PAI-1 device (algorithm/assay only) against the predicate device. The precision studies also evaluate the Spectrolyse® PAI-1 device in isolation. "Standalone" performance here refers to the device's ability to produce quantitative results for PAI-1 activity.
7. Type of Ground Truth Used
- Type of Ground Truth: The "ground truth" for the method comparison studies was the quantitative result obtained from the predicate device, Spectrolyse® /pL PAI (manufactured by BIOPOOL, K922782). This is a comparison against an existing, legally marketed diagnostic assay. For the precision studies, the ground truth was the expected value of the control samples.
8. Sample Size for the Training Set
- Sample Size for Training Set: The document does not explicitly mention a "training set" in the context of machine learning or AI development. This is a traditional IVD device, not an AI-based diagnostic tool. The development process would have involved internal optimization and validation studies, but these are not typically referred to as a "training set" in this regulatory context.
9. How Ground Truth for the Training Set Was Established
- How Ground Truth for Training Set Was Established: Not applicable, as there is no explicitly defined "training set" for an AI algorithm. The device's operational parameters and calibration would have been established using reference materials and established laboratory methods during its development phase.
§ 864.7290 Factor deficiency test.
(a)
Identification. A factor deficiency test is a device used to diagnose specific coagulation defects, to monitor certain types of therapy, to detect coagulation inhibitors, and to detect a carrier state (a person carrying both a recessive gene for a coagulation factor deficiency such as hemophilia and the corresponding normal gene).(b)
Classification. Class II (performance standards).