The wearable artificial kidney has passed the first FDA-approved proof-of-concept trial, Victor Gura, MD, FASN and other researchers announced at the American Society of Nephrology’s Kidney Week 2015. The device was developed by Gura, from the David Geffen School of Medicine at UCLA. The present prototype of the WAK is a 10-pound device, powered by nine-volt batteries and worn around the waist.

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Chuck Lee, 73, was the first U.S. patient outfitted with the WAK in the United States. He has had diabetes for 40 years and has received traditional three times a week dialysis for more than two years, according to UW Medicine’s News Beat. Watch an interview with Lee below.

“Treatment with the WAK was safe, well-tolerated and effectively cleared patients’ uremic toxins while maintaining electrolyte and fluid balance,” Dr. Jonathan Himmelfarb, a UW Medicine nephrologist and director of the Kidney Research Institute at the University of Washington, where the trial was conducted, told UW Medicine’s News Beat. “These results serve as proof-of-concept that, after the device is redesigned to overcome technical problems, a wearable artificial kidney can be developed as a viable dialysis technology.”