Bioresorbable polystatin fourth-generation stents

Stents have evolved through three generations, the latest of which are totally bioresorbable to include drugs targeting restenosis, the surface polymer eluting those drugs, and scaffolds on which those drugs are coated. These scaffolds, however, thus far, have been pharmacologically inactive and remain a potential site for delivering a second drug. Therefore, we sought to evaluate the possibility of modifying a bioresorbable polymer so that it can double as a scaffold for both a stent and a drug targeting impaired re-endothelialization and stent thrombosis.

We successfully modified a standard bioresorbable terpolymer in a way found to be consistent with the covalent incorporation of lovastatin, as seen on NMR, into a backbone comprised of lactide, glycolide, ε-caprolactone, and lovastatin (60 : 15 : 10 : 15 parts by weight), respectively. This was accomplished through a reaction of the four components of the polymer at 100°C for 18 h in the presence of an alcohol initiator and a scandium catalyst. The resulting terpolymer was fabricated into a scaffold using a novel RSF system developed by 3D Biotek.

It preliminarily appears feasible to fabricate a fourth-generation bioresorbable stent that has the potential to deliver two drugs to the site of the procedure-related vessel lumen injury.