(72 days)
Enzygnost F1+2 (monoclonal) is an enzyme immunoassay for the quantitative determination of human prothrombin F1+2 in plasma. Measurement of F1+2 is used as an aid in the diagnosis, monitoring, and evaluation of acquired or hereditary blood coagulation disorders. It is indicated as an aid in assessing risk of thrombosis and in monitoring efficacy of anticoagulant therapy.
The Enzygnost™ F1+2 Test Kit is an enzyme immunoassay based on the sandwich principle in microtiter format utilizing monoclonal mouse antibodies. During the first incubation, the F1+2 antigen in the sample binds to F1+2 antibodies attached to the microtiter plate. After washing, peroxidase-conjugated antibodies to human prothrombin are bound to a free F1+2 determinant in a second reaction. The excess enzyme-conjugated antibodies are removed by washing; the bound enzyme activity is then determined. The enzymatic reaction between hydrogen peroxide and chromogen is terminated by the addition of dilute sulfuric acid. The color intensity, which is proportional to the concentration of F1+2, is determined photometrically and quantified by means of a calibration curve based on the standards included in the kit.
Here's an analysis of the provided information, structured to answer your questions about acceptance criteria and the supporting study for the Enzygnost™ F1+2 (monoclonal) device:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Correlation to Predicate Device | High correlation coefficient (target usually > 0.9) | 0.96 |
| Slope (vs. predicate) | Slope close to 1 | 0.265 (This indicates a significant difference in scale or measurement between the two devices and is not close to 1. However, the FDA found substantial equivalence, suggesting this difference was acceptable in the context of the device's function or that a conversion factor is implied. It's important to note the discrepancy if interpreting solely on a "close to 1" metric.) |
| Intercept (vs. predicate) | Intercept close to 0 | -29.378 (Similar to the slope, this indicates a bias between the two devices. The FDA's acceptance suggests this was deemed acceptable.) |
| Within-Run Precision (CV) | Low coefficient of variation (typical |
§ 864.7320 Fibrinogen/fibrin degradation products assay.
(a)
Identification. A fibrinogen/fibrin degradation products assay is a device used to detect and measure fibrinogen degradation products and fibrin degradation products (protein fragments produced by the enzymatic action of plasmin on fibrinogen and fibrin) as an aid in detecting the presence and degree of intravascular coagulation and fibrinolysis (the dissolution of the fibrin in a blood clot) and in monitoring therapy for disseminated intravascular coagulation (nonlocalized clotting in the blood vessels).(b)
Classification. Class II (performance standards).