Kidney disease, once commonly thought of as a single entity, has become far more complicated. That’s a good thing, because it opens the door for better and more precise treatments.
Back in 2002, the National Kidney Foundation published the five stages of kidney disease. That was an important step forward in classifying and treating chronic kidney disease, which affects 30 million Americans. These stages helped better identify the progression of the disease, as the tissue destruction and scarring captured in the stages cause an ongoing loss of kidney function.
Sixteen year later, genomics and proteomics have ushered in precision diagnoses and therapies for cancer and other diseases while leaving much of kidney disease behind. We need to update our understanding of this all-too-common disease and reclassify it based not simply on loss of kidney function but by combining kidney pathology with molecular and genetic make-up. This will open the field to new ideas and research that I strongly believe will lead to more targeted therapies directed at individuals’ specific needs.
One out of every seven adults in the United States is living with chronic kidney disease — millions of them aren’t aware they have the disorder. I have seen thousands of such people over my career as a kidney doctor. I have explained the risks of “silent” kidney disease that could lead to a life of dialysis or the need for a kidney transplant. For many people, the diagnosis is often sudden, unexpected, and devastating. The course can be a rapid decline or an extended, invisible progression.
The U.S. spends an enormous amount of money treating people with kidney disease. In 2015 (the last year with complete statistics), Medicare alone spent $98 billion to treat people with chronic kidney disease, more than 1 out of every 6 dollars spent. Given that outlay, it simply makes no sense that we invest so little in clinical research related to kidney disease. The funding of clinical trials for kidney disease by the National Institutes of Health is lower than for almost any other major medical specialty.
Creating an opportunity for more research and innovation in kidney disease can be accomplished only by a paradigm shift like the one we have seen in other areas of medicine, such as oncology. As a result of that shift, we now know that “breast cancer” is really a constellation of different cancer types.
Today, categorizing breast cancer is often supplemented with the tumor’s genetic markers or identification of a specific protein associated with the tumor. The identification of proteins such as HER-2 and BRCA gene expression has led to highly successful targeted therapies for these variations of breast cancer. Genomic profiling of a cancerous tumor is now commonplace and expected.
Kidney disease is currently identified mainly by how the tissue looks under a microscope without subclassification by molecular or genetic signatures.
Fortunately, many research facilities have begun untangling the molecular and genetic variations of chronic kidney disease. This process allows us to think of it not only by designations such as “minimal change disease,” “focal segmental glomerulosclerosis,” and “diabetic nephropathy,” but also by incorporating molecular or genetic tags. This will allow for the identification of distinct target pathways of the disease to treat.
Earlier this month, Washington University School of Medicine researchers identified a synthetic virus strain that might successfully deliver genetic material to damaged kidneys. This is one step among many toward creating new gene therapies that may someday slow or reverse the progression of kidney disease. But this excellent research is missing an essential part of the equation: identifying actual genes that can correct the processes that damage cells.
As described in the latest annual medical report from Fresenius Medical Care, where I work, when the classification of kidney disease is enhanced by molecular markers and genetic variations, we can unlock new pathways for clinical trials of targeted therapies for each subtype of this illness. Instead of having minimal access to healing therapies, patients with kidney disease will have access to a variety of targeted innovative therapeutics.
As a kidney specialist who spent many years caring for patients and who now leads clinical and scientific affairs for Fresenius, the largest kidney products and services company in the world, I know that innovation and research are essential for solving complex problems. That’s why we recently partnered with Humacyte, which has developed the first bioengineered blood vessel, which shows great promise for improving how patients experience dialysis.
Innovations like that are essential to making life better for people living with chronic kidney disease. But we simply cannot expect to develop new therapies unless we first update how we classify and understand these diseases. Let’s take a major step by using the power of genomics and proteomics to define a path forward.
Franklin W. Maddux, M.D., is the chief medical officer and executive vice president for clinical and scientific affairs at Fresenius Medical Care North America and clinical associate professor of medicine at the University of North Carolina School of Medicine.
