Objective: The goal of this Direct-to-Phase II SBIR project is to advance development of a needle-free hemodialysis access port device. The project stems from promising (Phase I equivalent) feasibility results with a novel vascular graft construct showing superior patency and resistance to infection, combined with exit site infection control performance demonstrated under a previously awarded Phase II grant. Significance: Hemodialysis patients require punctures with large needles several times a week for vascular access, most often into surgically created arteriovenous (AV) fistulas. This worsens quality of life, and tissue trauma-related issues such as infection and hematoma makes maintenance of a reliable long-term access difficult. For the 30-40% of patients unable to sustain a fistula, prosthetic AV grafts provide the safest option. However, these grafts are prone to thrombosis at the venous anastomosis, and needle trauma-related complications are worsened by the progressive damage to the grafts and the presence of a biofilm-prone foreign biomaterial. A device that could circumvent the issues associated with needle sticks and provide patient-friendly long-term vascular access with low complication rates would have a major impact. Innovation: STARport is a new percutaneous hemodialysis port under development that provides blunt cannula access into the lumen of an AV graft. It uses Healionics' proprietary STAR(r) biomaterial at the tissue interfaces to overcome the exit site infection issues that limite earlier attempts to commercialize similar port devices. STAR biomaterial has an optimized microporous structure demonstrated to promote capillary ingrowth, minimize fibrotic encapsulation, and enhance the body's natural defenses against bacterial biofilm development. For a STARport to have high impact, it must also overcome the prosthetic AV graft issues. An in vivo feasibility study with a new STAR-based AV graft construction showed a remarkable outcome. Superior patency vs. standard ePTFE controls was achieved by the complete inhibition of tissue capsular contraction around the graft exterior. Unlike most approaches (which attempt to minimize neointimal hyperplasia), suppressing the anaconda squeeze effect of the fibrotic capsule is a fresh and innovative approach that appears to restore the body's natural balance between neointimal hyperplasia and flow. Equally remarkable, the STARgraft also showed dramatically improved resistance to bacterial colonization. Approach:
Specific aims are demonstrating 1) long-term graft patency, and 2) dialysis access function, safety and reliability. The proposed R&D addresses the critical knowledge gaps needed to proceed toward IDE approval for human use. Project success will offer an improved quality-of-life option for dialysis patients, and it will also facilitate transitions to home dialysis treatment, significantl reducing the economic burden to the healthcare system.
End Stage Renal Disease (ESRD) affects a growing population, with more than 400,000 patients in the US presently undergoing regular hemodialysis treatment. Established methods require repeated penetration of the skin and blood vessels with needles for connection to external dialysis equipment. A needle free vascular access port would provide a much more patient friendly approach. Prior implanted devices with this objective suffered from infection at the port skin exit sites and the connected vascular graft with further limitations from graft blockages. Use of our tissue integrating biomaterials in port and graft construction shows both infection resistance and improved blood flow properties. These are applied in an improved needle free access device. Project success will lead to significant improvements in dialysis clinical effectiveness and efficiency and to economic advantages for both patients and society.
