A delivery system 1 comprises a catheter 2, and a drug coated angioplasty balloon 5 mounted on the catheter 2. The balloon 5 has a wrapped or folded delivery configuration and an expanded deployed configuration. A protective sleeve 10 surrounds the drug coated balloon 5 in the delivery configuration to minimise wash-off of drug from the balloon during delivery. A spacer is mounted to or integral with the protective sleeve 10. The spacer in one case comprises interior ribs or ridges 14 on the sleeve 10 which minimise the surface area of the sleeve 10 in direct contact with the drug coating on the balloon. The ridges or ribs 14 also provide added column strength for advancing through a lesion.
