Prodrugs and their polymeric conjugates (transport forms) offer many promising modalities for new cancer chemotherapies. They present unique opportunities to increase the therapeutic index of a particular drug by exploiting the properties associated with the disease in a predictable fashion. Drugs can be chemically modified with a promoiety to achieve an exclusive selectivity by utilising specific enzymes, fenestrated vasculatures, more acidic environments and other unique properties of the tumour. Additionally, by incorporating a promoiety into existing immunoconjugates, greater efficacy can be achieved.
