Recent randomized clinical trials conducted by researchers from the UT Health Science Center in San Antonio and in Australia revealed ZS-9 as a new oral drug that controls high potassium levels in the blood. ZS-9 is the lead experimental therapy being developed by Coppell, Texas-based ZS Pharma. The results were presented at the National Kidney Foundation Spring Clinical Meetings 2015, Dallas, and appeared in The New England Journal of Medicine on Jan 15, 2015 in a study entitled “Sodium Zirconium Cyclosilicate in Hyperkalemia.”
High potassium levels in the blood, known as hyperkalemia, are associated with increased mortality among patients with heart failure, chronic kidney disease, or diabetes. Blood potassium, within certain values, is essential to control muscle contraction and required for normal heart electrical rhythm. Severe hyperkalemia (potassium levels above 7 mmol/L) is considered a medical emergency, due to the risk of arrhythmia.
One of the major causes of hyperkalemia is kidney dysfunction, as potassium is normally excreted by the kidneys. Chronic kidney disease affects more than 20 million people in the U.S. and the incidence increases in people over 70, particularly those with diabetes. Hyperkalemia associates with a higher risk of death from cardiac arrhythmias at end-stage renal disease.
Medications used by these patients can also increase potassium levels. A significant percentage of patients, between 5-30%, develops hyperkalemia when treated with a class of medications called Renin Angiotensin Aldosterone System inhibitors (RAASI’s). Kidney dialysis removes the excess of potassium through urine production and is the ultimate treatment to reestablish normal potassium levels in these patients. These results showed the effectiveness and safety of ZS-9 by normalizing potassium levels in 10000 patients through selectively binding of potassium in the intestines. “Dialysis is logistically difficult for patients, requires a catheter and is expensive,” Wajeh Y Qunibi, professor of medicine in the School of Medicine at the Health Science Center said in a news release. “In our studies, patients took a dose by mouth three times daily with meals, and potassium normalized in 98 percent of them within 48 hours. This is a major change in the way to treat hyperkalemia,” he added.
Importantly, ZS-9 is an effective option to prevent kyperkalemia in patients under RAASI’s treatment as these drugs are also important to slow down the progression of chronic renal disease.