Nucleic Acid Based Drugs (NABDs) constitute a class of promising and powerful therapeutic novel agents with limited side effects, potentially useable against a wide range of diseases, including cancer. Among NABDs, short interfering RNAs (siRNAs), represent very effective molecules. Despite their efficacy in vitro, the major drawback that limit siRNAs usage consists of the delivery difficulties; these are mainly due to the very low stability in physiological fluids and to the limited permeability through physiological barriers. On the other side, liposomes (lipid bilayers closed in vesicles of various sizes) are an interesting class of drug delivery system (DDS) that can be tailored to get the best performance in terms of load, vesicle size and transfection yield for many drugs including siRNAs. In this work, the current state of siRNA delivery based on the use of liposomes is discussed.
