Influence of aPTT reagents on the 1-stage clotting assay activity in human plasma determined for recombinant FIX products
Herbert Gritsch, Stefan Romeder-Finger, Friedrich Scheiflinger, Peter L. Turecek
Baxter Innovations GmbH, Vienna, Austria
RIXUBIS is a new recombinant factor IX (FIX) product produced from CHO cells using the protein-free manufacturing technology. Potency assignment is performed with a one-stage clotting assay (OSCA) based on the activated partial thromboplastin time assay (aPTT). The test is calibrated against the 4th WHO IS for FIX concentrates. RIXUBIS and another rFIX product were analyzed for FIX activity using a panel of aPTT reagents from various manufacturers and with chromogenic assays. Results were compared with the labeled potency. The impacts of type and source of the aPTT reagent were investigated.
Summary & Conclusions