The small-scale production of a severely heated factor VIII concentrate is described. As starting material for the production 48 units of fresh frozen plasma from whole-blood donations or 24 units of plasma from apheresis are used. During a glycine and sodium chloride fractionation, contaminating proteins are removed from a pooled extract of single-donor cryoprecipitates. The resulting factor VIII-rich precipitate is redissolved in freeze-drying buffer and this solution is desalted by diafiltration. After filtration, this solution is dispensed into 10 vials and frozen. The product is freeze dried, and heat treated at 80°C for 72 h. The mean yield of the heat-treated product improved from 160 IU factor VIII per liter plasma at the start of the production to 215 IU per liter plasma after a modification of the purification process. The validation of the virus inactivation during freeze-drying and 80°C heat treatment for 72 h showed a reduction of ≥ 7.6 log PFU/ml for Sindbis and a reduction of ≥ 6.4 log TCID(50)/ml for HIV-1. The factor VIII concentrate was clinically tested in 6 patients. It possessed a normal half-life, showed a high recovery and no side effects. A Dutch license was granted in June 1991 and since then this product has been routinely manufactured in three Dutch blood banks.