PROPERTIES OF A F VII CONCENTRATE.

A concentrate of factor VII obtained by adsorption onto an inorganic adsorbent using a by-product of routine fractionation as starting material This fraction contains only small amounts of the other constituents of the prothrombin complex ( PC ) but it is enriched in proteins C and S. It contains much less VIII CAg than the usual even activated PC concentrates. The amounts of isoagglutinins anti-A and B have also been checked. The concentrate of partially versus completely activated factor VII ( by factor Xlla ) has been submitted to animal experiences including those effected on hemophilic dogs. The concentrate and highly purified factor VII prepared from it were checked on a serie of chromogenic substrates and inhibitors of proteolytic enzymes of plasmatic and other origin. The results obtained are compared with those given by the two most commonly used activated PCCs. The correlation between active F VII and by-passing activity has been studied. This concentrate might thus be indicated for the treatment of hemophilia A-patients with inhibitors.