AN UPDATED REVIEW OF STEALTH LIPOSOMES AND ITS ABILITY TO EVADE THE IMMUNE SYSTEM: A NEW FRONTIER IN CANCER CHEMOTHERAPY

Liposomes have been the delivery of choice for the cancer targeting therapy for the last few decades. Since the 1990s, the development of sterically stabilized (stealth) liposomes has garnered interest for their long circulating half-life. PEGylated (Polyethylene Glycol) liposomes are most extensively studied for delivering cancer therapeutics in a sustained manner. Stealth liposomes are having a less intrinsic toxicity with higher efficacy in cancer treatment. There are numerous clinical trials on the liposomes in tackling cancer is evident for the better outcome of the delivery system. Stealth liposomes are extensively studied for their improved circulation time and better pharmacokinetic profile in cancer treatment. The steric hindrance of the stealth liposomes bypasses the reticuloendothelial system clearance. Further the ligands conjugation in the surface of the liposomes able to achieve better target to the cancer cells. The vascularization nature of the cancerous cells is readily making the liposomal delivery of the cancer drugs accumulate in the cancerous cells rather than healthy cells. There is an utmost need to understand the possible mechanism of stealth liposomes and the basic science behind the development of liposomal delivery system in advancing the cancer treatment with less toxicity. The present review addresses the various modalities of the liposomal development, liposome characterization, mechanism of PEGylated liposomes, the advancements and results of the liposomes in the treatment of various diseases, and the clinical trials and regulatory considerations of liposomal drug delivery system.