The use of macromolecules as carriers of antitumor drugs

Abstract

The purpose of this investigation is an extension of the use of protein carriers to various types of antitumor drugs, including antimetabolites and antitumor antibiotics. The variety of carriers has also been increased by the use of branched chain synthetic polymers with a poly- l-lysine backbone. Most drug-protein combinations were non-covalent in nature. Murine antitumor results are discussed based on the evaluation of activity in the leukemia L 1210 and P 388 systems. In several cases the therapeutic efficacy of an antitumor drug was increased by macromolecular complexation. This effect was partly due to reduced toxicity and seems to be dependent on the choice of carrier as well as the choice of drug. Actinomycin D, cytosine arabinoside, 5-azacytidine and dichloromethotrexate appear to be good candidates for a macromolecular complex approach to cancer chemotherapy.