Prediction of Biodegration and Drug Release from a Biodegradable Stent

摘要

A drug-eluting stent generally consists of a metallic stent platform with a polymeric coating that encapsulates a drug. In recent times, a large number of clinical trials have demonstrated that local drug delivery using drug-eluting stents can inhibit several of these processes thereby preventing or minimizing restenosis. However, metallic stent platforms might not be the most ideal means of drug delivery. A metallic stent significantly alters the local compliance of the artery making the stented segment much stiffer than a native artery and there is a potential for the stent to fail under long term fatigue loading. Further, the permanent metallic implants might interfere with future interventional procedures. Therefore, ideally it is desirable to have a stent that provides sufficient support to the arterial wall upon deployment delivers a therapeutic dose of the drug to prevent restenosis and then degrades to non-toxic products either during the drug release process or after the drug delivery is completed. Biodegradable polymers such as Poly(lactic acid) [PLA] have been investigated for stent based drug delivery.