Cancer therapy with chemically modified enzymes. I. Antitumor properties of polyethylene glycol-asparaginase conjugates.

摘要: The covalent attachment of monomethoxypolyethylene glycol (PEG) to asparaginases from Escherichia coli and Vibrio succinogenes by new coupling methodology produced conjugates that are active, stable, without significant immune response, with greatly extended plasma half-lives in mice. Therapeutic efficacies were greater for the PEG-asparaginases than unmodified mice infected L5178Y lymphosarcoma or 6C3HED tumor. Large single doses native modified enzymes more effective against tumors same amount enzyme given smaller over several days.