(197 days)
The Ultegra Rapid Platelet Function Assay - TRAP (RPFA -TRAP) is a semi-quantitative, whole blood platelet function assay used to measure glycoprotein (GP) IIb/Illa receptor blockade in patients treated with abciximab or eptifibatide. Ultegra RPFA-TRAP results should be interpreted in conjunction with other clinical and laboratory data available to the clinician.
The Ultegra System is a turbidimetric based optical detection system which measures platelet induced aggregation as an increase in light transmittance. The system consists of a stand-alone analyzer and disposable test cartridge with reagents based on microbead agglutination technology. The quality control system includes an electronic control and two levels of liquid control. The analyzer controls assay sequencing, establishes the assay temperature, controls the reagent-sample mixing for the required duration, determines the degree of platelet function, displays the results and status information to the user, and performs self-diagnostics. The test cartridge contains a lyophilized preparation of human fibrinogen coated beads, thrombin receptor activating peptide (iso-TRAP), buffer, and preservative. The patient sample is whole blood, which is automatically dispensed from the blood collection tube into the test cartridge by the analyzer, with no blood handling required by the user.
The Ultegra RPFA Assay is based upon the ability of activated platelets to bind fibrinogen. Fibrinogen coated microparticles agglutinate in whole blood in proportion to the number of unblocked platelet GP Ilb/Illa receptors. The rate of microbead agglutination is more rapid and reproducible if platelets are activated. Therefore the reagent iso-TRAP is incorporated into the assay to induce platelet activation without fibrin formation. As activated platelets bind and agglutinate fibrinogen coated beads, there is an increase in light transmittance which is measured by the Ultegra Analyzer. Results are reported in Platelet Aggregation Units (PAU).
The provided document is a 510(k) summary for the Accumetrics Ultegra® System Rapid Platelet Function Assay (RPFA), focusing on its substantial equivalence to a predicate device. It primarily describes the device, its intended use, and a comparative performance study. It does not explicitly state "acceptance criteria" as typical clinical trial endpoints with specific thresholds (e.g., sensitivity > X%, specificity > Y%). Instead, the study's goal was to demonstrate "substantial equivalence" to a predicate device based on correlation and visual overlap of inhibition curves.
Here's an attempt to extract and interpret the requested information based on the provided text, acknowledging that some specific criteria (like numerical acceptance thresholds) are not explicitly stated.
Acceptance Criteria and Device Performance Study for Accumetrics Ultegra® System RPFA
1. Table of Acceptance Criteria and Reported Device Performance
As explicit numerical acceptance criteria for a "new" device approval (e.g., target sensitivity, specificity) are not present in this 510(k) summary for a substantial equivalence claim, the acceptance was based on demonstrating correlation and similar performance to the predicate device.
| Aspect of Performance | Acceptance Criteria (Implicit from Substantial Equivalence Claim) | Reported Device Performance (Ultegra RPFA-TRAP vs. CHRONO-LOG Platelet Aggregometer) |
|---|---|---|
| Correlation with Predicate Device (Abciximab treated patients) | Strong correlation (e.g., correlation coefficient approaching 1) and linear relationship with the predicate device. | Deming (orthogonal) Regression: |
- Slope: 2.91
- Intercept: -48.58
- Correlation (r): 0.89 |
| Time Course of Platelet Inhibition (Abciximab treated patients) | Visual overlap and similar trends in platelet inhibition over time compared to the predicate device and an independent receptor blockade assay (RBA). | Figure 1 (description): Shows overlap in time course of platelet inhibition for RPFA, AGG (CHRONO-LOG), and RBA. |
| Time Course of Platelet Inhibition (Eptifibatide treated patients) | Visual overlap and similar trends in platelet inhibition over time compared to the predicate device and an independent PAC1 Flow Cytometric Assay. | Figure 2 (description): Shows overlap in time course of platelet inhibition for RPFA, Agg (CHRONO-LOG), and PAC1. |
| Claim of Substantial Equivalence | Performance characteristics demonstrate that the new device is "substantially equivalent" to the predicate device. | "The Ultegra RPFA-TRAP performance was compared with the performance of the CHRONO-LOG Platelet Aggregometry in multi-center clinical trials... The results of the multi-center clinical studies demonstrate that the performance of the Ultegra RPFA-TRAP is substantially equivalent to that of the predicate device, CHRONO-LOG platelet aggregometer." |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (Test Set):
- Abciximab treated patients: 120 patients
- Eptifibatide treated patients: Number not explicitly stated, but "samples were obtained... from patients treated with eptifibatide."
- Data Provenance:
- Country of Origin: Not explicitly stated, but clinical trials were "multi-center," indicating multiple locations. Given the 510(k) submission to the FDA, it is highly likely the studies were conducted in the USA.
- Retrospective or Prospective: The description "Multi-center clinical trials were designed to study GP IIb/IIa receptor blockade in patients undergoing percutaneous coronary intervention and receiving abciximab or eptifibatide. Samples were obtained... at three time points: 1) Baseline... 2) During... and 2) Post..." strongly suggests a prospective collection of data during the course of patient treatment.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This study relies on a comparative approach against a predicate device (CHRONO-LOG Platelet Aggregometer) and other established assays (RBA, PAC1 Flow Cytometric Assay), rather than establishing "ground truth" through expert consensus on individual case interpretations. The performance of these comparator methods is the standard against which the Ultegra RPFA-TRAP is measured. Therefore, information on the number and qualifications of experts for establishing ground truth in the traditional sense is not applicable or provided.
4. Adjudication Method for the Test Set
Not applicable. The study compares the device's measurements against those of established laboratory methods, not against expert interpretation of images or clinical outcomes requiring adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This study is for an in-vitro diagnostic device measuring a physiological parameter, not for an imaging device requiring human reader interpretation. The comparison is between the new device and existing laboratory tests for platelet function.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
Yes, the performance study describes the standalone performance of the Ultegra RPFA-TRAP system "assay." The system performs the measurement and reports results (Platelet Aggregation Units) without human interpretation as part of its core function, akin to other laboratory assays. The "correlation" and "time course of inhibition" figures represent this standalone output compared to other standalone laboratory tests.
7. The Type of Ground Truth Used
The "ground truth" in this context is the measurement obtained by established comparator methods for platelet function inhibition. Specifically:
- CHRONO-LOG Platelet Aggregometer: A predicate device commonly used for measuring platelet aggregation.
- Receptor Blockade Assay (RBA): Measures the percentage of blocked GP IIb/IIIa receptors.
- PAC1 Flow Cytometric Assay: Another method for assessing platelet inhibition.
These methods, rather than clinical outcomes or pathology, serve as the reference for validating the new device's measurements.
8. The Sample Size for the Training Set
The document does not explicitly mention a separate "training set" or its sample size. This is a 510(k) submission focused on clinical performance for demonstrating substantial equivalence. For algorithmic devices, training data is often distinct from validation data, but this document does not distinguish such sets for the Ultegra RPFA. The assay itself consists of reagents and an analyzer, implying a development and optimization process (which would involve internal testing/training) rather than an explicit "training set" for an AI algorithm.
9. How the Ground Truth for the Training Set Was Established
Since an explicit "training set" is not detailed, the method for establishing its "ground truth" is also not provided. For an IVD device like this, the development process would involve optimizing reagent formulations and analyzer parameters to accurately measure platelet function, likely using reference methods and well-characterized samples during the development and internal validation phases. However, this is not described in the 510(k) summary as a dedicated "training set" process with ground truth establishment in the context of an AI/ML algorithm.
§ 864.5700 Automated platelet aggregation system.
(a)
Identification. An automated platelet aggregation system is a device used to determine changes in platelet shape and platelet aggregation following the addition of an aggregating reagent to a platelet-rich plasma.(b)
Classification. Class II (performance standards).