The invention describes factor VIII molecules with reduced capacity to elicit activation of NKT cells for use in the treatment of congenital and/or acquired haemophilia A and in bleeding disorders. Said factor VIII molecule is obtainable by: a. identification of at least one NKT cell epitope wherein said epitope comprises hydrophobic aminoacid residues in position P1 and/or P7 b. modification of said epitope(s) by eliminating at least one hydrophobic aminoacid residue in position P1 and/or P7, substituting at least one hydrophobic aminoacid residue in position P1 and/or P7 with a non-hydrophobic residue, or adding a non-hydrophobic residue in position P1 and/or P7.