Search Results

The Rapidpoint™Coag Enoxaparin Test card (ENOX) is a qualitative test intended for exclusive use with the Rapidpoint Coag analyzer to detect the anticoagulant effects, ≥ 1.0 IU/ml, of the low molecular weight heparin (LMWH), Lovenox®/Clexane® (enoxaparin sodium)¹, in arterial citrated whole blood from patients with unstable angina (UA)/non-ST segment elevation myocardial infarction (NSTEMI) who may transition to percutaneous intervention (PCI). The ENOX test is intended for use at either the point of care or in the central laboratory. The device does not discriminate between values of enoxaparin below 1.0 IU/ml and the absence of drug.

The test provides information on the patient's citrated arterial whole blood response to enoxaparin by measurement of the clotting time using a factor Xa activated clotting method and should be interpreted in conjunction with other clinical data available to the clinician

The RapidPoint Enoxaparin (ENOX) test is a one-step dry coagulation method performed on the RapidPoint Coag analyzer. All of the components necessary to perform the assay, with the exception of patient sample, are included in the reaction chamber of the test card.

In the ENOX test, factor X is rapidly converted to factor Xa by a specific factor X activator initiating the clotting process. Enoxaparin, from the patient's blood, complexes with antithrombin (AT), to inhibit factor Xa and lengthen the clotting time. Reported clotting times in excess of the assay cut-off indicate an enoxaparin concentration greater than or equal to 1.0 International Units per milliliter. The results generated by the ENOX test are indicative of the anticoagulant effect produced by enoxaparin in citrated arterial whole blood.

The test card formulation contains purified Factor Xa activator, calcium, phospholipid and stabilizers. Paramagnetic iron oxide particles (PIOP) are included to provide an optical detection mechanism in the presence of patient sample.

Here's a summary of the acceptance criteria and study details for the Thrombolytic Assessment System (TAS) or Rapidpoint™ Coag Enoxaparin (ENOX) Test Card.

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the clinical study's results in relation to the intended use. The device is intended to detect enoxaparin levels ≥1.0 IU/mL. The study uses a clotting time cutoff of ≥ 260 seconds to indicate this.

2. Sample Size and Data Provenance for the Test Set

• Sample Size (Clinical Study): 88 patients
• Data Provenance: Prospective, from "6 sites in the United States."
• Sample Type: Arterial citrated whole blood samples, collected at baseline (no drug) and at peak values (within 15 minutes of dosing) after enoxaparin administration. The samples were tested in duplicate.

3. Number of Experts and Qualifications for Ground Truth of the Test Set

The document does not explicitly state the number of experts used to establish ground truth for the test set.

• Ground Truth Method: The ground truth for the clinical study was established by comparing the ENOX card clot times to "central laboratory measured plasma anti-Xa levels." This implies that the central lab results, likely interpreted by qualified laboratory personnel, served as the reference standard. The qualifications of those performing the anti-Xa level measurements are not specified, but it's assumed to be standard clinical laboratory practice.

4. Adjudication Method for the Test Set

The document does not mention an adjudication method for the test set. The comparison was made directly between the device's output and the central lab's anti-Xa results.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not performed. This device is an in-vitro diagnostic (IVD) assay designed to provide a direct measurement, not an imaging or diagnostic aid that human readers would interpret to improve their performance with or without AI assistance. Therefore, there is no effect size reported for human readers improving with or without AI.

6. Standalone (Algorithm Only) Performance

Yes, the provided data describes the standalone performance of the algorithm (the ENOX Test Card used with the RapidPoint Coag analyzer). The sensitivity and specificity reported are for the device itself, without human interpretation influencing the final "positive" or "negative" determination based on the 260-second cutoff.

7. Type of Ground Truth Used

The type of ground truth used for the clinical study was: central laboratory measured plasma anti-Xa levels.

8. Sample Size for the Training Set

The document does not explicitly state the sample size for a "training set." The performance data presented focuses on the clinical validation of the device. However, "In-House Data" for reproducibility used unspecified numbers of "citrated plasma with and without the addition of 1.0 (anti-Xa) IU/ml enoxaparin" and "venous citrated whole blood from single donors." These in-house studies likely contributed to the optimization of the assay (e.g., establishing the 260-second cutoff), which could be considered an internal development/training phase.

9. How the Ground Truth for the Training Set Was Established

For the in-house reproducibility studies (which might loosely correspond to an internal development/training phase):

• Ground Truth Method: Ground truth appears to have been established by directly spiking known concentrations of enoxaparin (0.0 IU/ml and 1.0 IU/ml) into citrated plasma or venous whole blood. This provides a clear, controlled, and known ground truth for evaluating the device's basic performance and reproducibility at specific enoxaparin levels.

Ask a specific question about this device