Development and performance characteristics of a competitive enzyme immunoassay for fibrinopeptide A

A simple nonisotopic method for the quantitation of FPA in biologic samples has been developed utilizing a competitive enzyme immunoassay technique. The performance characteristics of these assays have been investigated in both the experimental and clinical settings and were found to be satisfactory for the routine clinical application. This method is comparable to a commercially available RIA kit (Mallinckrodt, St. Louis, MO) in both the clinical and normal samples. This assay can be used in the diagnosis of hypercoagulable states associated with various diseases. Subclinical activation of coagulation can be readily assessed when the global tests, such as the prothrombin time, partial thromboplastin time, and thrombin time, have no value. This test is of value in the monitoring of the newer antithrombotic agents, such as the low molecular weight heparin fractions that do not effect the global assays, such as the partial thromboplastin time. Similarly, the risk of thrombosis associated with the use of procoagulant therapy, such as the activated prothrombin complex concentrates, can be readily assessed using this assay. It is proposed that the FPA measurement may also provide useful information on the quality control of various plasma-based therapeutic products, such as plasma concentrates or activated prothrombin complex concentrates. FPA generation tests are currently proposed for the screening of antithrombotic and prohemostatic agents.