December 13, 2019
Ten grams of sodium zirconium cyclosilicate three times a day for up to 48 hours reduced serum potassium to normal levels in patients with hyperkalemia without any serious adverse events, according to a study in BMC Nephrology.
“Sodium zirconium cyclosilicate is an oral, nonabsorbed, high-capacity cation-binding compound that selectively exchanges serum potassium for hydrogen and sodium ions throughout the gastrointestinal tract,” researchers wrote. “SZC is thought to start binding potassium in the upper gastrointestinal tract, which most likely accounts for its rapid onset of action.”
The study was a pooled analysis of two phase 3 trials involving a total 170 patients who received 10 grams of SZC three times daily. Among the patients, 73.5% had a potassium level between 5.5 mmol/L and 5.9 mmol/L, 22.9% had a potassium level between 6.0 mmol/L and 6.5 mmol/L, and 3.5% had a potassium level higher than 6.5 mmol/L at baseline.
Within 1 hour of the initial SZC dose, average potassium dropped regardless of patients’ baseline level, researchers reported. Four hours after the initial dose, 37.5% of patients achieved a potassium level of 5.0 mmol/L or less. Within 48 hours, the proportion of patients with a normal potassium level was 85%.
Nearly 9% of patients experienced adverse events, most of which were gastrointestinal. No serious adverse events were recorded.
“These results may be of particular interest to hospitalists, observation/short-stay unit providers, and urgent care and emergency department providers, who may see patients with hyperkalemia and are uncertain about their clinical trajectory,” researchers wrote. “These patients are currently observed in these settings for variable periods of time at a high cost, and the results of this analysis may help guide the treatment and transition plans for these patients.”
Amin AN, Menoyo J, Singh B, Kim CS. Efficacy and safety of sodium zirconium cyclosilicate in patients with baseline serum potassium level ≥ 5.5 mmol/L: pooled analysis from two phase 3 trials. BMC Nephrology. 2019;20(1):440.