Orlando—Patiromer is a potassium binder approved by the US FDA for the treatment of hyperkalemia. The TOURMALINE study was designed to examine the efficacy and safety of once daily patiromer given with food compared with once daily patiromer given without food for the treatment of hyperkalemia.
P.E. Pergola, MD, and colleagues reported results of the study during a poster session at the NKF 2017 Spring Clinical Meetings. The poster was titled Patiromer Lowers Serum Potassium (K) When Taken With or Without Food.
The study included 114 adults in the United States with two screening potassium values >5.0 mEq/L who were randomly assigned to patiromer 8.4 g once daily either with or without food for 4 weeks with titrations at day 3 and weeks 1, 2, and 3 to achieve and maintain serum potassium 3.8 to 5.0 mEq/L. With food was defined as the start of a meal to 30 minutes following a meal; without food was defined as 1 hour before a meal or 2 hours after a meal.
The end points of interest were between group comparisons for percent of patients with week 3 or 4 serum potassium values 3.8 to 5.0 mEq/L, and the least square mean change from baseline to week four in serum potassium.
There were 112 patients eligible for evaluation. Of those, 65% were male, 65% were >65 years of age, 12% were black, 56% were Hispanic/Latino, and 44% had stage 4 or 5 chronic kidney disease (patients with end-stage renal disease were excluded). In all, 92% (n=103) completed the study. Of the 103 who completed the study, 87.3% of patients in the with-food group and 82.5% of those in the withoutood group achieved the primary end point.
There was no difference between the two groups in least square change from baseline to week four in serum potassium (–0.65 mEq/L with-food and –0.62 mEq/L without-food; P=.789). After adjustments for race, estimated glomerular filtration rate, type 2 diabetes mellitus, or other variables, overall the percentage of patients who achieved the primary end point was consistent.
Patients with higher serum potassium levels at baseline had greater reductions in potassium. The rates of adverse events were similar between the two groups and consistent with prior trials of patiromer. The most common adverse events were diarrhea (5.3%), constipation (3.5%), abdominal pain (1.8%), and vomiting (1.8%). Six patients experienced a serious adverse event, none of which were study related.
“Once-daily patiromer significantly reduced serum potassium in hyperkalemia patients, with >80% achieving and maintaining serum potassium between 3.8 and 5.0 mEq/L. There was no difference in efficacy or safety when patiromer was given with or without food,” the researchers said.
Source: Pergola PE, Spiegel DM, Warren S, Yuan J, Weir MR. Patiromer lowers serum potassium when taken with or without food. Abstract of a poster presented at the National Kidney Foundation 2017 Spring Clinical Meetings, April 19-22, 2017, Orlando, Florida.