Inactivation of Poliovirus Type-1 and HSV-1 in Human Coagulation Factor VII Concentrate by Pasteurization

Background-Pasteurization is now available to treat products derived from plasma to inactivate transfusion-transmitted enveloped and non-enveloped viruses.Objective-This study was performed to assess the capacity and efficacy of virus inactivation by pasteurization in human coagulation factor VII concentrate with two model viruses including poliovirus type 1 (non-enveloped) and herpes simplex virus type 1 (enveloped).Methods-The viruses were added to the stabilized factor VII (70% sucrose, 20% glycine) and pasteurized for 10 h at 60° C. Viral infectivity was tested in vitro on cell culture (Vero) using standard microtitration assays and the virus titer was expressed as log10 TCID50/ml.Results-On completion of the pasteurization procedure, 6.3 log of poliovirus type 1 and 5.8 log of HSV-1 were inactivated. Recovery of factor VII activity using sucrose/glycine as stabilizer was 80%. Other stabilizers showed lower recovery of factor VII and were less suitable.Conclusion-Viral inactivation by pasteurization procedures destroys both enveloped and non-enveloped viruses and can be applied to production of factor VII from plasma with relatively good recovery and can improve the safety of replacement therapy in hemophilia patients with inhibitors.