A human factor VIIa concentrate and its effects in the hemophilic A dog.

Properties of a new concentrate of FVII/FVIIa, obtained by adsorption onto an inorganic adsorbent followed by a chromatographic step onto Q-Sepharose using a by-product of routine fractionation as starting material, are described. This fraction contains only small amounts of the other components of the prothrombin complex but it is enriched in Proteins C and S. This preparation is essentially free of FVIIICag. It has been submitted to animal experiments including those carried out on normal and hemophilic A dogs. A normalization of the buccal bleeding time was seen after injection of a minimal dose of 4 uFVIIa/kg. No adverse reaction was observed at any dose employed. This concentrate might thus be indicated for the treatment of Haemophilia A patients with inhibitors. Its viral inactivation has been achieved.