Determination of Biological Activity of Recombinant Reteplase Using Clot Lysis Time and Activated Partial Thromboplastin Time (APTT) Lysis Methods: A Comparative Study

Recombinant plasminogen activator (reteplase) is a third generation thrombolytic agent which has been used on coronary artery thrombosis and acute myocardial infarction. Clot lysis assay is usually considered as a unique method to evaluate biological activity of reteplase. In this study biological activity of reteplase was determined by APTT (activated partial thromboplastin time) lysis method. Validity of this method was evaluated in comparison with reference method, clot lysis time assay. Results of APTT lysis test showed good reproducibility (relative standard deviation (RSD) 3-5% for within day analysis and 4-7% for between day analysis), and accuracy (101.3-102.7%). APTT lysis responses were linear in range of 0.001-0.1 mg/mL reteplase. Therefore, APTT lysis method is applicable for biological activity determination of reteplase. Although more comprehensive studies are required to approve this test as a reference method, APTT lysis method seems to be valuable to receive more attention due to advantages of technical simplicity, sensitivity, applicability, and cost efficiency.