The Future of Technology-Based Kidney Replacement Therapies: An Update on Portable, Wearable, and Implantable Artificial Kidneys.

Worldwide, the number of people who need lifesaving kidney replacement therapy (KRT) steadily increases, but approximately two thirds of them lack access to KRT and therefore die. Access to KRT depends on economic, social, infrastructural, ecological, and political factors. Current KRTs include kidney transplant, peritoneal dialysis, and hemodialysis. The field of xenotransplantation has been opening promising new perspectives recently but needs improvement. Unfortunately, not all patients are suitable for transplant. Peritoneal dialysis and hemodialysis will remain important KRTs, but they are expensive and strongly dependent on infrastructure, with few fundamental changes since the 1980s. The KRT field might learn from the "African mobile phone revolution" that beat infrastructural limitations, lowered costs, and increased access. We provide a nonexhaustive overview of promising ways to increase the mobility of technology-based KRTs by dialysate regeneration, chip-based nanoporous filters, bioreactor-enabling technologies, and using the gut as a "third kidney." In 2018, the Kidney Health Initiative published a road map for innovative KRTs composed by leading innovators, but the pace of innovation is slower than was targeted. Ambitious political statements about realizing this road map can only succeed if the granted funding matches the targeted time scale. Patient-centered international "coopetition" (ie, the act of cooperation between competing entities) seems to offer the quickest pathway to success.