Potential clinical applications for drug-coated balloons
Drug-coated balloon catheters have the potential to play an important role in treating both coronary and peripheral vascular disease. Although stents, angioplasty catheters and other technologies have significantly advanced our understanding and treatment of cardiovascular disease, DCBs may offer unique alternatives in treating a number of specific clinical indications that are not as well served by existing therapies.
Drug-coated balloons also offer ease-of-use and familiarity to physicians by utilizing delivery systems and inflation devices similar to standard angioplasty catheters commonly in use today.
Two Lutonix DCB balloon systems are under development — one optimized for peripheral interventions and a second for coronary interventions. To date, the Lutonix DCB drug-coated balloon catheter has been evaluated in several studies. Two first-in-man coronary studies and one peripheral study (LEVANT I) have been conducted in Europe.
Potential peripheral applications
Within the peripheral vasculature, DCBs are being evaluated for the treatment of disease in the superficial femoral (SFA), popliteal and tibial-peroneal arteries. These arteries have always posed special challenges for clinicians due to their anatomy and need to accommodate the extreme motion requirements of the lower extremity.
Unlike stents, DCBs do not leave an implant behind. As a result, primary stand-alone DCB use would eliminate concerns about vessel flexion, which can result in stent fractures. Drug-coated balloons, used alone, also allow clinical flexibility in treating both short, focal lesions and extremely long, diffuse disease without concerns about overlapping metal implants.
Lutonix plans to initiate a global randomized clinical study upon receipt of IDE approval.
Long, diffuse lesions and the frequent presence of calcium have meant fewer treatment options for disease below the knee. DCBs require further clinical study for use in this anatomy, but could offer unique benefit in their ability to treat arteries as small as 1.5 mm and lesions 200 mm or longer.
Potential coronary applications
Today, coronary interventions most commonly involve a combination of balloon angioplasty and stenting (either drug-eluting or bare-metal stent). Unlike stents, DCBs treat the artery without leaving any permanent implants behind.
For this reason, drug-coated balloons may be attractive for treating:
In-stent Restenosis (ISR)
ISR refers to previously placed stents that have become occluded due to the buildup of scar tissue within the stent itself, and represents a very challenging clinical problem. While stents can be used to treat ISR, their use requires leaving a second layer of metal in the artery permanently.
DCBs may offer an advantage in treating lesions located in side branch arteries. When stents are placed in the parent artery, inadvertent obstruction of a side branch artery is possible. DCBs may offer an advantage in these lesions without posing an obstruction risk.
No therapeutic options exist currently for arteries 2.0 mm in diameter and smaller. Arteries 2.25 – 2.5mm can be treated with stents and regular balloon angioplasty, but restenosis rates can be higher¹.
¹ Elezi S, Dibra A, Mehilli J, Pache J, Wessely R, Schömig A, Kastrati A. Vessel size and outcome after coronary drug-eluting stent placement: results from a large cohort of patients treated with sirolimus- or paclitaxel-eluting stents. J Am Coll Cardiol. 2006; 48(7):1304-9.