Novel metal-based anticancer drugs: a new challenge in drug delivery.

Since the serependitous discovery of the cisplatin antiproliferative activity, many efforts have focused on the design of potent metal-based drugs for oncology therapies. A large number of these complexes have been evaluated in vitro and in vivo and some have reached clinical trials. However, while metallodrug chemistry has developed to an advanced level, these emerging therapeutics have encountered new hurdles including poor water solubility and pharmacological deficiencies. Today, solutions to overcome these issues do not lie in synthesizing new anticancer drugs but in finding suitable drug delivery strategies. Over the past decades, various delivery systems have been developed including prodrug, ligand design and nanocarriers aimed at enhancing the performance profile of these novel metallodrugs.