title: The pre-clinical assessment of rapamycin-eluting, durable polymer-free stent coating concepts.
abstract: All four currently FDA-approved drug-eluting stents (DESs) contain a durable polymeric coating which can negatively impact vascular healing processes and eventually lead to adverse cardiac events. Aim of this study was the pre-clinical assessment of two novel rapamycin-eluting stent (RES) coating technologies that abstain from use of a durable polymer. Two distinctive RES coating technologies were evaluated in vitro and in the porcine coronary artery stent model. The R-poly(S) stent platform elutes rapamycin from a biodegradable polymer that is top coated with the resin shellac to minimize the amount of polymer. The R-pro(S) stent platform allows dual drug release of rapamycin and probucol, blended by shellac. HPLC-based determination of pharmacokinetics indicated drug release for more than 28 days. At 30 days, neointimal formation was found to be significantly decreased for both DESs compared to bare-metal stents. Assessment of vascular healing revealed absence of increased inflammation in both DESs, which is commonly observed in DES with non-erodible polymeric coating. In conclusion, the pre-clinical assessment of RESs with resin-based or dual drug coating indicated an adequate efficacy profile as well as a beneficial effect for vascular healing processes. These results encourage the transfer of these technologies to clinical evaluation.
authors.affiliation: Deutsches Herzzentrum, Klinikum rechts der Isar, Technische Universität, Munich, Germany.
authors.forename: Kristin
authors.initials: K
authors.lastname: Steigerwald
authors.forename: Sabine
authors.initials: S
authors.lastname: Merl
authors.forename: Adnan
authors.initials: A
authors.lastname: Kastrati
authors.forename: Anna
authors.initials: A
authors.lastname: Wieczorek
authors.forename: Marc
authors.initials: M
authors.lastname: Vorpahl
authors.forename: Raimund
authors.initials: R
authors.lastname: Mannhold
authors.forename: Michael
authors.initials: M
authors.lastname: Vogeser
authors.forename: Jörg
authors.initials: J
authors.lastname: Hausleiter
authors.forename: Michael
authors.initials: M
authors.lastname: Joner
authors.forename: Albert
authors.initials: A
authors.lastname: Schömig
authors.forename: Rainer
authors.initials: R
authors.lastname: Wessely
mesh_terms: D000818:Animals; D020099:Coated Materials, Biocompatible; D003331:Coronary Vessels / Q000187:drug effects / Q000473:pathology; D004353:Drug Evaluation, Preclinical; D054855:Drug-Eluting Stents; D008422:Materials Testing; D008670:Metals; D011108:Polymers / Q000737:chemistry*; D020123:Sirolimus / Q000493:pharmacokinetics / Q000494:pharmacology*; D013552:Swine; D016896:Treatment Outcome; D014945:Wound Healing / Q000187:drug effects
chemical_list: D020099:Coated Materials, Biocompatible; D008670:Metals; D011108:Polymers; D020123:Sirolimus