CANCER-THERAPY WITH CHEMICALLY MODIFIED ENZYMES .1. ANTITUMOR PROPERTIES OF POLYETHYLENE GLYCOL-ASPARAGINASE CONJUGATES

  • 1 January 1984
    • journal article
    • research article
    • Vol. 7 (2), 175-186
Abstract
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 and with greatly extended plasma half-lives in mice. Therapeutic efficacies were greater for the PEG-asparaginases than for the unmodified asparaginases in mice infected with the rat L5178Y lymphosarcoma or the mouse 6C3HED tumor. Large single doses of native or modified enzymes were more effective against tumors than the same amount of enzyme given in smaller doses over several days.