[Development and characterization of a high-purity human factor VIII concentrate submitted to 2 specific virus...

To develop a therapeutic human high purity FVIII concentrate, treated with two documented and complementary specific inactivation methods, for the treatment of haemophilia A.

Cryoprecipitate was obtained from human plasma, normal for ALT levels and negative for HBsAg and antibodies to HIV and to HCV. The cryoprecipitate was resuspended and purified with PEG. The PEG precipitate was resuspended and treated with TNBP/Polysorbate 80. The mixture was processed by heparin affinity chromatography. The eluate was concentrated and precipitated with glycine and salts. After resuspension, stabilizers were added and the solution was sterile filtered, dispensed in vials and lyophilized. These final vials were treated at 80 degrees C for 72 hours: FVIII:C, vWF:RCo, vWF:Ag, vWF multimeric structure and the concentration of other plasmatic proteins were analyzed.

FVIII: C specific activity was between 1000 and 3000 U/mg (after elimination of vWF, present as a stabilizer and before the addition of human pasteurized albumin). vWF:RCo activity (0.7 U vWF:RCo/U FVIII:C) and the multimeric structure of vWF showed a good degree of conservation. Other plasmatic proteins analyzed were undetectable or at trace amounts. No prekalllikrein, kallikrein or activated coagulation factors activity could be detected.

The FVIII concentrate described shows a high degree of purity and stability, which makes it very suitable for haemophilia A treatment.