processes for improving the in vivo function of factor viii by shielding exposed targets of the factor viii comprise a ) immobilizing the factor viii by interaction with a group - specific adsorbent carrying ligands manufactured by organic - chemical synthesis , for preventing polymer coupling to reactive amino acids of the immobilized factor viii , within or adjacent to interaction domains ; b ) activating a biocompatible polymer ; c ) conjugating the activated biocompatible polymer to external sites of the immobilized factor viii ; and thereafter d ) eluting the conjugate from the adsorbent . processes for administering factor viii comprise subcutaneously , intramuscularly , intradermally or intravenously administering a conjugate of factor viii and a biocompatible polymer , and methods for treatment of hemophilia a comprise subcutaneous , intramuscular , intradermal or intravenous administration of a conjugate of factor viii and a biocompatible polymer .