The main objective of COST Action D20 was to further develop the chemistry of metal-containing compounds to be applied in cancer chemotherapy and eventually in antiviral therapy. Among the many scientific achievements of the Action, it is worth noting that two ruthenium compounds and a gallium compound developed within COST D20 have reached the phase of clinical trials in humans as novel anticancer agents. The first ruthenium compound, termed NAMI-A, has accomplished phase 1 clinical trials and entered phase 2 in 2006. NAMI-A was the first ruthenium compound ever to reach the stage of evaluation on humans. The second ruthenium compound, KP1019, has also completed a phase 1 clinical trial. These accomplishments have involved the establishment of connections with several European industrial companies. At a more fundamental level, the following scientific achievements of D20, among many others, may deserve to be highlighted: * the investigation of the interactions of new potential antitumor platinum compounds with cellular components and their biological consequences. In particular, assessment of the distortions induced in DNA by these compounds, and recognition and repair of these distortions by specific proteins. * the development of novel organometallic anticancer compounds and, in particular, of a class of ruthenium(II) arene complexes that specifically target guanine bases of DNA oligomers and form monofunctional adducts. * the development of potential “supramolecular metallo-drugs”, i.e. polycationic cylindrical or spherical metallo-agents of appropriate size and bearing surface recognition functionality that recognize the major groove of DNA through supramolecular interactions. Action D20 has been instrumental in the creation of excellence in Europe in the field of anticancer metal compounds, with a very high level of scientific activity. COST D20 has allowed its members to adopt world-leading positions in the field and establish new contacts with industry, especially SMEs. The scientific results have been presented in a large number of publications in refereed journals and through the plenary lectures that members of the Action have been invited to give at major international conferences. The educational impact of Action D20 became evident in a special session of the Final Conference of the Action, entitled ‘Raised in D20’, where several young scientists who had done their doctoral or postdoctoral work within the Action and had benefited from scientific exchanges presented their results.
