Progress in purification of virus-inactivated factor VIII concentrates. Three generations of solvent/detergent treated plasma derivatives.

A production process of a newly developed highly purified and virus-inactivated Factor (F) VIII-concentrate (Octa V.I. and Octavi) is presented. Taking advantage of a selective resin matrix and the solvent/detergent procedure for virus inactivation--known not to denaturate proteins--a product of a specific activity greater than or equal to 100 IU F VIII/mg could be developed in the final container without the use of an immuno-affinity adsorption step. The main steps of the procedure are: Pooled cryoprecipitate is extracted, the extract is cleared from fibrinogen at + 10 degrees C and virus-inactivated at + 28 degrees C after addition of tributyl-phosphate (TNBP) and detergent. Thereafter the extract is brought in contact to a F VIII-selective anion exchange resin using a chromatographic column. TnBP and the detergent are removed by an extensive washing process and the F VIII-activity is concentrated in a fraction, ready for filling, by means of a cascade of wahing- and elution-buffers. The product is free from coagulable protein and gamma-globulins. The F VIIIC: Ag/F VIII:C-ratio is about unity, suggesting the F VIII-molecule remained in its native state. The development of highly purified F VIII concentrate is based on two previous products of lesser purity (spec. activity of about 1 and 10 IU/mg). The evolution is shown by a comparison of detailed analytical data.