Safety, Healing, and Efficacy of Vascular Prostheses Coated with Hydroxypropyl-β-cyclodextrin Polymer: Experimental In Vitro and Animal Studies

ObjectivesPolyester vascular prostheses (PVPs) coated with a polymer of hydroxypropyl-β-cyclodextrin (HPβCD) have been designed to provide an in situ reservoir for the sustained delivery of one or more bioactive molecules. The goal of this study was to assess the efficacy, the safety and the healing properties of these prostheses.MethodsCollagen-sealed PVPs were coated with the HPβCD-based-polymer (PVP-CD) using the pad–dry–cure textile finishing method and loaded with one or two antibiotics. Appropriate control and PVP-CD samples were tested in several in vitro and animal model conditions. The study end points included haemolysis, platelet aggregation, antibacterial efficacy, polymer biodegradation, acute toxicity and chronic tolerance.ResultsPVP-CD proved to be compatible with human blood, since it did not induce haemolysis nor influenced ADP-mediated platelet aggregation. Sustained antimicrobial efficacy was achieved up to 7 days against susceptible bacteria when PVP-CDs were loaded with the appropriate drugs. Analysis of harvested PVP-CD from the animal model revealed that the HPβCD-based coating was still present at 1 month but had completely disappeared 6 months after implantation. All grafts were patent, well encapsulated without healing abnormalities. Clinical data, blood-sample analysis and histological examination did not evidence any signs of acute or chronic, local or systemic toxicity in the animal models.ConclusionPVP-CD was proved safe and demonstrated excellent biocompatibility, healing and degradation properties. Effective antimicrobial activity was achieved with PVP-CD in conditions consistent with a sustained-release mechanism.