Value-based insurance design in oncology.

www.thelancet.com/oncology Vol 12 April 2011 321 virus without any observable resistance or physiological side-eff ects. This treatment has advanced to phase 2 clinical trials, which emphasises the strengths of antimiR-122, including high effi cacy and good tolerability without adverse eff ects. As the results of years of eff ort begin to show the eff ects of miRNAs in cancer, a few candidate miRNAs have emerged as therapeutics to prevent and treat various stages of tumorigenesis. However, the notion of treating cancer with miRNA replacement or miRinhibitors is still at its infancy and requires more functional in-vivo studies. Safe and effi cacious delivery mechanisms also need to be established. Development of miRNA therapy, which employs miRNA’s pleiotropic role in gene regulation, has the potential to overcome the limitations of present cancer therapies. Although targeted therapies such as imatinib and erlotinib have given many cancer patients tremendous benefi t by tailoring therapy to a tumour’s genetic profi le; redundancy and complexity of signal pathways often leads to relapse even with combined targeted therapies. Based on present preclinical trials, combination of miRNA therapy with targeted or traditional therapies might be able to create a synergistic eff ect for treatment of cancer and become an alternative treatment for cancer. Many biotechnology companies have miRNA therapeutics programmes, and human clinical trials, which should begin in the next few years, will show whether the high expectations of this novel approach are warranted.