Bioartificial Kidney Meeting Research Milestones
A pioneering implantable artificial kidney developed jointly by teams of researchers at Cleveland Clinic, the University of California at San Francisco, and the University of Michigan in Ann Arbor is on track to meet project milestones in a pilot and feasibility study funded by the NIH.
The device is a hybrid of high-tech nanoscale silicon membranes and living kidney cells designed to support patients who have renal failure without the need for external machines or dialysate. The project is in the second year of the feasibility study, which is intended to stress-test key technologies needed for a full-scale device that would serve as a third alternative to dialysis and transplantation.
We are working to develop the novel membranes essential to the success of the implantable artificial kidney and coordinating membrane testing and bioreactor development. A second-phase proposal will be submitted to the NIH in late winter. This scale-up phase of the project will take the bioartificial kidney from components on a lab bench to a clinical trial in patients.
Clinical experience with extended daily dialysis suggests that a total dose of dialysis almost four times as much as is routinely provided today can improve nutrition, quality of life, cardiac disease, and even reproductive health in dialysis patients.
At the same time, the numbers of patients starting dialysis each year continues to rise. Approximately 400,000 patients in the United States depend on dialysis to live, and 80,000 patients are on the kidney transplant wait list. These two pressures—a need for more therapy and more people who need it—conflicts with the financial need for cost containment in health care.
Dialysis patients cost Medicare about 10 times as much as the average Medicare patient, and the Medicare Trust Fund is projected to become insolvent in 10 years—well within the lifetimes of some patients on dialysis today. Therefore, alternatives to reduce cost associated with renal failure are desperately needed.
This technology provides a third path for patients with renal failure—an implantable hybrid device combining high-efficiency filters with living cells. The device, based on silicon nanotechnology, overcomes fundamental barriers to implantable approaches to dialysis—the size of the dialyzer and pumps, and the need for dialysate.
The high-efficiency hemofilter is powered by the patient's own BP, eliminating the need for blood pumps. Derived from technology developed by David Humes, MD, and his team at the University of Michigan, the bioreactor of human kidney cells recycles the ultrafiltrate and concentrates it into urine, which can be directed to the patient's own bladder.