title: The SYNERGY biodegradable polymer everolimus eluting coronary stent: Porcine vascular compatibility and polymer safety study.
abstract: OBJECTIVE
  SYNERGY is a novel platinum chromium alloy stent that delivers abluminal everolimus from an ultrathin poly-lactide-co-glycide (PLGA) biodegradable polymer. This study evaluated the in vivo degradation of the polymer coating, everolimus release time course, and vascular compatibility of the SYNERGY stent.
  
  
  RESULTS
  SYNERGY stents were implanted in arteries of domestic swine. Devices were explanted at predetermined time points (up to 120 days) and the extent of PLGA coating or everolimus remaining on the stents was quantified. Everolimus levels in the arterial tissue were also evaluated. A pathological analysis on coronary arteries of single and overlapping stents was performed at time points between 5 and 270 days. PLGA bioabsorption began immediately after implantation, and drug release was essentially complete by 90 days; PLGA absorption was substantially complete by 120 days (>90% of polymer was absorbed) leaving a bare metal SYNERGY stent. Vascular response was similar among SYNERGY and control stents (bare metal, polymer-only, and 3× polymer-only). Mild increases in para-strut fibrin were seen for SYNERGY at an early time point with no significant differences in all other morphological and morphometric parameters through 270 days or endothelial function (eNOS immunostaining) at 90 or 180 days. Inflammation was predominantly minimal to mild for all device types.
  
  
  CONCLUSIONS
  In a swine model, everolimus was released by 90 days and PLGA bioabsorption was complete shortly thereafter. The SYNERGY stent and its biodegradable polymer, even at a 3× safety margin, demonstrated vascular compatibility similar to bare metal stent controls.
authors.affiliation: Department of Pediatric Laboratory Medicine, Division of Pathology and Research Institute, Division of Physiology and Experimental Medicine, Hospital for Sick Children, Toronto, Ontario, Canada and Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Wilson
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Angela
authors.initials: A
authors.lastname: Marks
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Kimberly J
authors.initials: KJ
authors.lastname: Berg
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Michael
authors.initials: M
authors.lastname: Eppihimer
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Natalia
authors.initials: N
authors.lastname: Sushkova
authors.affiliation: Department of Pediatric Laboratory Medicine, Division of Pathology and Research Institute, Division of Physiology and Experimental Medicine, Hospital for Sick Children, Toronto, Ontario, Canada and Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Steve P
authors.initials: SP
authors.lastname: Hawley
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Robertson
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: David
authors.initials: D
authors.lastname: Knapp
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Pennington
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Yen-Lane
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Aaron
authors.initials: A
authors.lastname: Foss
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Barbara
authors.initials: B
authors.lastname: Huibregtse
authors.affiliation: Boston Scientific Corporation, Marlborough, Massachusetts.
authors.forename: Keith D
authors.initials: KD
authors.lastname: Dawkins
mesh_terms: D020341:Absorbable Implants; D015906:Angioplasty, Balloon, Coronary / Q000379:methods* / Q000401:mortality; D000818:Animals; D020099:Coated Materials, Biocompatible; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D004195:Disease Models, Animal; D054855:Drug-Eluting Stents; D019544:Equipment Failure Analysis; D000068338:Everolimus / Q000008:administration & dosage*; D005260:Female; D008670:Metals; D011108:Polymers / Q000737:chemistry*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D011897:Random Allocation; D012680:Sensitivity and Specificity; D015996:Survival Rate; D013552:Swine
chemical_list: D020099:Coated Materials, Biocompatible; D008670:Metals; D011108:Polymers; D000068338:Everolimus
keywords: OMEGA; SYNERGY; coronary; drug-eluting stent; everolimus; porcine