David Sterman

Warren Buffett loves to invest in stable businesses with few competitors.

One of his recent favorites is DaVita HealthCare (NYSE: DVA), which operates a network of dialysis treatment centers in the United States catering to patients that have diabetes-induced kidney failure. Buffett's Berkshire Hathaway (NYSE: BRK-B) has been a steady buyer for several years and now owns nearly 30 million shares, equating to a $1.8 billion stake.

But DaVita has a big problem on its hands. Dialysis is expensive, and the two biggest payees for this procedure, Medicare and Medicaid, have been pushing DaVita and its rival Fresenius Medical Care (NYSE: FMS) to swallow painful reimbursement cuts.

It's not just the administration of dialysis that is costly. Many patients end up with side effects related to iron deficiency and red blood cell production, which costs billions more to remedy. And these costly treatments don't even yield the desired medical outcomes.

Thankfully, one of the biggest providers of the drugs and chemicals used in dialysis has a solution to the problem. Little-known Rockwell Medical (Nasdaq: RMTI) has been testing an iron supplement that goes right into bone marrow.

Patients on dialysis stop producing erythropoietin, a key ingredient in the production of red blood cells. A 2012 IMS Midas study found that almost all dialysis patients -- more than 400,000 in the U.S. and more than 2 million worldwide -- suffer from anemia.

In response, drug companies have been selling erythropoiesis-stimulating agents (ESAs), which help produce red blood cells, but a great deal of iron is consumed in the process. As a result, patients need to receive iron on an intravenous (IV) basis, though the current IV drips end up storing much of the iron in the kidneys instead of the bloodstream where it should be circulating.

David Sterman

David Sterman has worked as an investment analyst for nearly two decades. He is currently an analyst for StreetAuthority.com