Liposomes as Drug Products: the Regulatory Challenges

Noam Kirshenbaum, Nextar Chempharma, Nes Ziona, Israel (noamk@nextar.co.il)

Liposomes are promising drug delivery vesicles, composed of a lipid bilayer or membrane enclosing an internal aqueous core. Liposomes offer many advantages over classical small molecule formulations, enabling reduced toxicity, site-specific targeting, intracellular drug payload delivery and altering the pharmacokinetic properties of a drug. Liposomal drug products are a sub-group of Non-biological Complex Drugs (NBCD) and contain greater complexity in characterization and approval than small-molecule drugs. Much of the difficulty in developing and registering these immense drug-lipid complexes can result from variability between and within batches, requiring extensive characterization of the composition, variability, and stability of the liposomal component. Although several liposomal drugs have been successfully approved and used in clinics over the last few decades, the field is still at its infancy. Here, liposomal drug products approved by the FDA and EMA are presented. The current regulatory guidance and the future liposomal products perspectives are discussed, highlighting the customized development strategies needed on- route to registering novel liposomal drug product.