As anyone who has watched a medical drama knows, organs are in short supply and must be rushed everywhere in coolers, only to be delivered at the last possible moment. This is actually kind of true. In the U.S., 570,000 people suffer from chronic kidney failure, but last year there were only 16,812 kidneys available to be transplanted. A staggering 92,000 patients were left on the waiting list, which can be a death sentence.
There is no substitute for a real kidney, but researchers at UCSF and nine other labs have for years been working on an artificial version that can allow patients to live without dialysis, and without having to take immune suppressing drugs that normally prevent transplanted kidneys from being rejected by the body. This month, the FDA announced that it has selected the artificial kidney project for its Innovation Pathway, a program designed to help breakthrough technologies reach market faster than they might otherwise.
The implantable artificial kidney performs the water-balancing and metabolic functions of the real thing using lab-grown cells and nanofilters that remove blood toxins. No pumps or outside power supplies are needed; the body’s blood pressure pushes along filtration. "It’s a mechanical device combined with cells," explains Dr. Shuvo Roy, the leader of the artificial kidney project.
The device isn’t a perfect replica of a real kidney, but it provides enough functionality that patients can ditch dialysis and have complete freedom of mobility. The device can’t, for example, produce an important kidney chemical, called erythropoietin, which stimulates red blood cell production. Patients using the artificial kidney will have to take a drug for this, just like dialysis patients.
But unlike real transplanted kidneys, which have an average lifespan of 10 to 12 years, the artificial kidney can last indefinitely (new cells may have to be implanted through an injection or small port every two years.)
The kidney transplant waiting list won’t disappear anytime soon, even with the emergence of the artificial kidney. But the people who get kidneys from the waiting list are often close to death; healthier patients are left waiting. The artificial version could be an option for patients who are unlikely to get a real transplant.
Roy hopes that a clinical trial can begin in 2016. The device could be on the market by the end of the decade, with a price tag that’s comparable to what it currently costs to maintain a transplant (about $30,000 a year).
"One of the encouraging things for us is that the fundamental scientific basis for the artificial kidney has already been established. We know the concept works. The challenges ahead are mostly engineering challenges," says Roy.