A Bullet Proof vascular graft to prevent dialysis access cannulation injury

PROJECT SUMMARY End Stage Renal Disease (ESRD) affects more 750,000 individuals in the United States alone. Hemodialysis (HD) is a life-sustaining therapy for patients suffering from renal failure that requires blood to be withdrawn and cycled through a dialysis machine. This process requires repeated needle punctures and the consequent needle access to a surgically created vascular shunt. These shunts are often created by connecting an artery to a vein with a prosthetic synthetic conduit (arteriovenous graft [AVG]); these grafts, though widely used, suffer from many disadvantages. First, they do not allow for immediate cannulation as they require an initial period of 4 weeks for tissue incorporation and healing post implant. Thus, more than 85% of ESRD patients initiate HD via tunneled dialysis catheter (TDC) while their AVG heals. Because TDCs are associated with high morbidity and mortality rates, the prospect of an AVG that can be cannulated immediately post implantation may reduce morbidity in these patients. Second, HD access injuries caused by careless or poor cannulation practices can result in graft material degradation, pseudoaneurysm formation, bleeding, clots, and infections. There is no currently available AVG that offers immediate cannulation after implantation, facilitates successful, error-proof needle entry, and protects from access cannulation injury. To reduce these complications, InnAVasc Medical, Inc. has developed an immediate access hemodialysis graft that is deigned to assure routine, successful cannulation, prevents graft injury, and thus, could promote safer home HD; the Bullet Proof vascular graft (BPG). This graft is constructed of biocompatible materials and is designed to be immediately hemostatic, self-sealing and resistant to inadvertent posterior and sidewall needle penetration. In the Phase II project and early feasibility clinical study, we confirmed the BPG could be successfully implanted in all subjects and that the device was well tolerated. Furthermore, the cannulation chamber worked as intended to allow for immediate access and prevent needle-related injuries. However, due to a lack of adequate strain relief at the soft graft to chamber transition zones, there was a higher rate of early graft thrombosis than clinically acceptable. We have tested the revised graft on the bench compared to the original BPG and it outperforms the original in all aspects of luminal integrity. Furthermore, clinical data from a small feasibility study in South America confirmed the new strain relief prevented early thrombosis. Therefore, we are confident that the revised BPG will perform as expected in terms of function, flow, and patency in the next planned clinical study. In this Phase IIB, we will further the commercial development of the revised BPG and achieve our specific goal of the project by conducting a pivotal clinical study to evaluate its safety and effectiveness for HD access in subjects with ESRD. This will be a prospective, multicenter, single arm, clinical study conducted at seven sites in the US with a planned enrollment of 60 subjects with ESRD. A 510(k) application will be submitted to the US Food and Drug Administration with six months of patient follow-up as the primary analysis.