Fanhdi (Grifols, Barcelona, Spain) and Alphanate (Grifols, Los Angeles, CA, USA) are plasma derived factor VIII (FVIII) concentrates containing von Willebrand factor (VWF) that are used for treating hemophilia A and for which no specific model describing their pharmacokinetics (PK) has been developed. This evidence concerns the gene F8 and hemophilia A.