Ultraflexible lipid vesicles allow topical absorption of cyclosporin A

Psoriasis and atopic dermatitis are widespread pathologies with a need to improve their treatment. Topical administration of cyclosporine A (CyA) could be used if targeted to the skin, thus avoiding systemic levels. Unfortunately, CyA molecular weight and lipophilicity prevent its diffusion through human skin. Four novel lipid vesicles have been prepared by different methodologies to overcome this problem. The vesicles were characterized in terms of particle size, size polydispersity, Z-potential, morphology, drug encapsulation, phospholipid content, and vesicle flexibility. Freeze-drying in presence and absence of cryoprotective agents was also performed, to guarantee long-term stability. The ability to deliver CyA into the skin was assessed using human epidermis in Franz diffusion cells and compared with the delivery of drug solutions with enhancers. The technical characteristics of four types of vesicle make them suitable to carry drugs. Moreover, these liposomal formulations were able to effectively deliver CyA in vitro into the skin. The present work introduces a promising approach for the topical treatment of skin pathologies with an immune component.