Section Review: Oncologic, Endocrine & Metabolic: Liposomal chemotherapy for AIDS-related Kaposi's sarcoma

Abstract

Drug encapsulation within a liposome offers a potential therapeutic advantage by preventing interaction of the drug with plasma components and extending the duration of exposure of the target to the drug. Previous liposomal studies have been hindered by the rapid clearance of the liposome by cells of the reticuloendothelial system. Developments in membrane technology and production standards have allowed development of a range of new liposomal agents which show activity without the problems of previous generations of the drugs. Kaposi's sarcoma has been used as a trial neoplasm for two types of liposomal anthracycline. DaunoXome, a liposomal preparation of daunorubicin, shows high response rates with minimal toxicity when used for advanced systemic AIDS-related KS. Dox-SL, a liposomal preparation of doxorubicin, shows similar activity but with a differing range of toxicity. Liposomal membranes differ for both drugs and are predominantly responsible for the differences in toxicity. Phase I and II studies show that the drugs are active with toxicity less than would be expected with conventional combination chemotherapy for AIDS-related KS. The results of Phase III studies are awaited and the roles of such drugs in commoner, solid malignancies are being explored.