Removal of Potentially Thrombogenic Material from a Concentrate of Factors II, IX & X by Polyethylene Glycol Precipitation

Polyethylene glycol(PEG) precipitation has beer used for the removal of hepatitis B surface antigen (HBsAg) from a concentrate of factors II, IX & X of intermediate purity. HBsAg is precipitated into a fraction PI at 20% (w/v) PEG and pH 6.5 while factors II, IX & X remaining in the supernatant are subsequently precipitated at 30% (w/v) PEG and pH. 5.2

These various fractions have been assessed for the presence of potentially thrombogenic materials by in vitro tests. In comparison with the starting material the precipitate rich In factors II, IX & X has a significantly increased non-activated partial thromboplastin time (NAPTT) and a decreased rate of factor Xa generation. By contrast the waste fraction (PI) exhibits a significantly decreased NAPTT and an increased rate of factor Xa generation suggesting that potentially thrombogenic material has been selectively precipitated. This procedure has been used to prepare a factor II, IX & X concentrate containing 100 U FIX/ml with reduced contamination by both HBsAg and thrombogenic materials.