Investigational drug prevents life-threatening side effects of kidney disease treatment

A yearlong study of more than 300 patients found that the investigational drug patiromer can reduce elevated blood-potassium levels—a common side effect of drugs essential in the treatment of chronic diabetic kidney disease.

The drug, given in this trial at one of four doses based on disease severity, returned blood potassium levels to normal when measured at four weeks and kept them under control for one year—the length of the trial. By quickly bringing potassium levels back to normal and keeping them there, patiromer can prevent life-threatening adverse events.

The study, published July 14 in JAMA: The Journal of the American Medical Association, is the first to follow patients taking patiromer for more than a few weeks.

In patients with mild or moderate potassium elevation, known as hyperkalemia, patiromer for oral suspension decreased serum potassium levels within 48 hours. For most of those patients, potassium levels remained within the target range at every scheduled visit for the next year. When patients stopped taking the medication, potassium levels in the blood began to increase within three days. Hyperkalemia recurred within eight weeks.

“This is a significant advance, a huge deal,” said George Bakris professor of medicine and director of the Comprehensive Hypertension Center at the University of Chicago Medicine. “It affects everyone with stage 4 or 5 chronic kidney disease, almost 1 million people in the United States.”

The only alternative is a 50-year-old drug that is “difficult to take, poorly tolerated and unpredictable,” Bakris said. “Most patients won’t take it.”

Previous research demonstrated the short-term benefits of patiromer, but this is the first study to follow patients beyond four weeks. Patients for whom it is appropriate would take the medication indefinitely.

The findings “have the potential to fundamentally change the current treatment approach to hyperkalemia,” according to an accompanying editorial by nephrologist Wolfgang Winklemayer of Baylor College of Medicine. The novelty of the study, he added, “lies in the secondary results.” Potassium levels remained essentially stable throughout the maintenance phase, but after the end of the study, “potassium concentrations increased quickly and significantly, once again.”

—Adapted from a news release from the University of Chicago website. Read it in its entirety here.