ANTIBODY-TARGETED DRUGS FOR THE THERAPY OF CANCER

The advent of monoclonal antibodies has revitalised the concept of mag ic bullets and various agents (eg. drugs, toxins and isotopes) have be en conjugated to monoclonal antibodies for selective delivery to tumou rs. Preclinical studies in mouse tumour models have been impressive an d have lead to several clinical trials. These phase I trials have been less impressive. However keeping in mind the aim of Phase I trials, t he safety of using these conjugates in humans have been established. S everal, major problems still remain to be overcome before these agents may be useful for the treatment of cancer. These problems stem from t he nature of tumour vasculature, cytotoxic activity of the moiety link ed to antibody and the targeted tumour antigen expressed on the cell s urface. This review will deal with these Various aspects described abo ve and possible approaches to overcome these obstacles with a definite bias towards drug-monoclonal antibody conjugates. However, these conc epts are equally applicable for improved targeting of other agents.