Praque – A team of researchers headed by Dr. Valdimir Kral, Director of Chemical Development at Sanofi-Aventis’ Czech research unit Zentiva Development sro, has presented a new targeted drug delivery system that couples combined delivery of cytostatics and therapeutic antibodies to tumours with photodynamic therapy (Bioorg Med Chem Letter, doi:10.1016/j.bmcl.2011.06.101). Their new nanocarrier consists of a cyclodextrin shell enclosing the chemotherapeutic that is attached to a zinc-porphyrin system. This accumulates in tumour cells, and can bind immunoglobulins via the 5th coordination site of the Zn complex. According to the researchers, the system can be just as readily used for a variety of therapeutic and targeting proteins, including antibodies, lectins, and HSA. The new carrier allows an attack on tumours from three fronts. Porphyrine accumulates in them, leading to photo-oxidative tumour damage upon light activation (photodynamic therapy). Additionally, the system guides cell-toxic chemotherapeutics and cancer-selective immunotherapeutics into tumour cells. And when tested in a mouse model with human C32 carcinoma, the coordination assembly nanosystem was shown to be therapeutically superior in terms of efficacy to the building blocks used for the construction of the system alone.