Recombinant human factor VIII derivatives

A DNA sequence coding for a biologically active recombinant human factor VIII derivative, comprising a first DNA segment coding for the amino acids 1 through 740 of human factor VIII and a second DNA segment coding for the amino acids 1649 through 2332 of human factor VIII, said segments being interconnected by a linker DNA segment coding for a linker peptide of at least 3 amino acid residues and up to about 10 amino acid residues which are selected from lysine and arginine; recombinant expression vector comprising such DNA sequence; host cells of animal origin transformed with such recombinant expression vector; a process for the manufacture of recombinant human factor VIII derivative; and human factor VIII derivative containing the heavy chain and the light chain linked by metal ion bond.