Theresa M Allen1
1University of Alberta, Edmonton, Alberta, T6G 2H7, Canada
Several passively targeted drug delivery systems (DDS) have received clinical approval in the last two decades, and the first generic products are already appearing on the market. The use of ligands to target drug carriers selectively to specific target cells (sometimes called ‘active’ targeting) has been an established technology for almost two decades, but, despite some promising animal data, as yet no ligandtargeted therapeutics have received clinical approval, and very few products are in clinical trials. The advantages and disadvantages of active vs. passive targeting will be analyzed.