Trends in immunoconjugate and ligand-receptor based targeting development for cancer therapy

Many agents used to treat cancer are toxic to normal tissues. Thus, treatments delivering drug specifically to tumour, while minimising exposure to normal tissue, may be advantageous over non-targeted treatments. The exquisite specificity of the immune system has been used successfully to help develop targeted anticancer agents. The most common (and successful) tissue-specific targeting strategies rely on antibody conjugates, but additional approaches, including targeting through cytokines, peptides and recombinant viruses, have also been used successfully. This review summarises the agents exploiting the immunological principles of target specificity to help maximise delivery to tumour while minimising collateral damage to normal tissues. Such targeted molecules are collectively referred to as immunoconjugates.