Preclinical and clinical studies of anticancer drug-incorporated polymeric micelles.

Tumour-targeted delivery of therapeutic agents is a longstanding pharmacological goal to improve selectivity and Therapeutic Index. Most scientists have sought to use 'active' receptor-mediated tumour-targeting systems, however the 'passive' targeting afforded by the Enhanced Permeability and Retention (EPR) effects provides a versatile and non-saturable opportunity for tumour-selective delivery. Polymeric micelles are ideally suited to exploit the EPR effect, and they have been used for the delivery of a range of anticancer drugs in preclinical and clinical studies. Here I overview some of the more important approaches, assessing usefulness and seeking to identify the most promising ways to apply the phenomenon of passive targeting for improved clinical outcome.