IMPACT OF LIPOSOMES AS DELIVERY SYSTEMS IN VETERINARY-MEDICINE

The development of drug resistance and the inability of the drug to re ach the location of the etiologic agents are major challenges for anti -infective and cancer therapies. As the development of new drugs with improved pharmacodynamic and pharmacokinetic properties is a slow and difficult process, drug delivery systems appear as promising alternati ves. Liposomes are lipid vesicles formed when phospoholipids are expos ed to an aqueous environment. They arrange themselves in bilayers and close up, forming a vesicle. During this process they capture the aque ous phase of the dispersion, and any substance dissolved in it, within the vesicle. Liposomes have remarkable features that make them an alm ost ideal delivery system. They are biodegradable, with few side effec ts, can deliver drugs with different physico-chemical properties toget her and can be formulated for different routes of administration. The potential to modify the pharmacokinetic behaviour of encapsulated drug s to deliver them selectively to the site of action is the most import ant feature of liposomes as drug delivery systems. Liposomes are alrea dy used in human medicine for the treatment of bacterial, viral and pa rasitic diseases, and cancer. They have also been proven useful as imm unoadjuvants and vaccines. Liposomes are used in certain avian vaccine s. The possible uses of liposomes and their impact in veterinary medic ine in the treatment of infectious diseases and cancer as well as in t he prevention of diseases are discussed in the present article. (C) In ra/Elsevier, Paris