Factor VIII concentrate prepared from DDAVP stimulated blood donor plasma.

Human fraction I-0 (AHF-Kabi) was prepared from plasma from blood donors who had received an i.v. injection of DDAVP (0.2 microgram per kg b.w.) and tranexamic acid (0.01 g per kg b.w.) 15 min before collection of the blood. The factor VIII preparation from such plasma contained twice as much VIII:C,VIIIR:Ag, and VIIIR:RFC as normal fraction I-0. Normal fraction I-0 and DDAVP fraction I-0 were given to 2 patients with severe haemophilia A. The in vivo response of the DDAVP fraction I-0 corresponded to the in vitro values. No differences in survival time were seen. Hence, it is possible to produce factor VIII concentrates with at least double the yield by increasing the factor VIII level in blood donors by i.v. injection of DDAVP.