Development of liposomal formulations: From concept to clinical investigations

Liposome is one of the most successful drug delivery systems applying nanotechnology to potentiate the therapeutic efficacy and reduce toxicities of conventional medicines. Since the first doxorubicin-loaded liposome reached the market, numerous researches have been carried out to develop new liposomal formulations over the past decade and have given birth to a series of commercial products. Therapeutic agents, most of which are anti-cancer drugs, are encapsulated in the aqueous core or lipid bilayers of liposomes to improve their delivery to the targeted tissue. There are several liposomal formulations, such as EndoTAG-1 (paclitaxel-loaded cationic liposomes), Lipoplatin (cisplatin-loaded long circulating liposomes) and Stimuvax (a cancer vaccine), showing promising therapeutic value in clinical studies. Besides, new designs including environmentally sensitive liposomes, liposomal drug combinations and liposomal vaccines are now tested in clinical trials.