A Nanofibrous Bioactive Hemodialysis Access Graft

DESCRIPTION (provided by applicant): Current gold standards for hemodialysis access, radial cephalic vein fistulas and autogenous saphenous veins, have significant problems associated with their use. Many patients do not have a healthy vein to spare due to disease progression or prior/future use for a different surgical procedure (i.e. for a distal or coronary bypass). These surgical procedures also require greater time than a prosthetic graft implant due to vein harvesting. Synthetic grafts have issues with patency and inability to provide instant access. Our hypothesis is that the next generation of prosthetic hemodialysis grafts should possess multiple structural and biological properties that mimic some of those processes inherent to native arteries in order to prevent these complications from occurring. The goal of the Phase I study is to develop a first of its kind hemodialysis access graft comprised of polyester (PET) and polyurethane (PU) blend via electrospinning technology (BioAccess). Incorporation of these polymers as this unique blend will impart both strength and compliance to the graft. Specific biologic agents for preventing thrombosis (recombinant hirudin or rHir), infection (Moxifloxacin) and hyperplasia (Paclitaxel), will be blended in the graft. The incorporation of these agents should aid in the healing of the graft by preventing acute thrombosis, chronic infection and stenosis of the conduits during the repeated cannulation of the graft. The specific objectives of our proposed study are to: 1) optimize electrospinning conditions for the nanofibrous BioAccess graft, 2) characterize physical, chemical and surface properties of the graft, 3) evaluate release pharmacokinetics of rHir, Moxifloxacin and Paclitaxel from the BioAccess graft via a stringent washing study and 4) examine antithrombotic, antimicrobial and anti-proliferative properties of the graft using established biologic assays. The overall annual cost of ESRD treatment in the US is 23 billion, which is projected to increase 3.6% every year. About 2 million patients worldwide (355,000, currently in US alone) will receive hemodialysis treatment by 2010. With increasing age of dialysis patients and higher occurrence of diabetes and obesity, there is an urgent need for hemodialysis grafts with immediate access and better healing properties. PUBLIC HEALTH RELEVANCE: End Stage Renal Disease (ESRD) affects millions of people worldwide with the total cost of treatment in US alone standing at 23 billion. With increasing age, diabetes and obesity associated with the patients, there is a need for better hemodialysis access grafts that provide instant access and faster healing. The goal of this Phase I grant is to develop a novel hemodialysis graft from polyester (PET) and polyurethane (PU) through the process of electrospinning, incorporating antithrombotic (recombinant hirudin), antimicrobial and antineoplastic (Paclitaxel) agents directly into the fibrous (Moxifloxacin) construct. Our hypothesis is that the strength and elasticity of the polymers combined with the synergisticbiological effects of the selected drugs should lead to a synthetic graft with improved healing, better long-term patency and instant access.