Patiromer Lowers Serum Potassium When Taken without Food: Comparison to Dosing with Food from an Open-Label, Randomized, Parallel Group Hyperkalemia Study.

BACKGROUND

Patiromer is a sodium-free, nonabsorbed, potassium binder approved for treatment of hyperkalemia. This open-label study compares the efficacy and safety of patiromer administered without food versus with food.

METHODS

Adults with hyperkalemia (potassium ≥5.0 mEq/L) were randomized (1:1) to receive patiromer once daily without food or with food for 4 weeks. The dosage was adjusted (maximum: 25.2 g/day) using a prespecified titration schedule to achieve and maintain potassium within a target range (3.8-5.0 mEq/L). The primary efficacy endpoint was the proportion of patients with serum potassium in the target range at either week 3 or week 4. Safety was assessed by adverse events (AEs) and laboratory testing.

RESULTS

Efficacy was evaluated in 112 patients; 65.2% were ≥65 years of age, 75.9% had chronic kidney disease, and 82.1% had diabetes. Baseline mean serum potassium was similar in the without-food (5.44 mEq/L) and with-food (5.34 mEq/L) groups. The primary endpoint was achieved by 87.3% (95% CI 75.5-94.7) and 82.5% (95% CI 70.1-91.3) of patients in the with-food and without-food groups, respectively; least squares mean changes in serum potassium from baseline to week 4 were -0.65 and -0.62 mEq/L, respectively (p < 0.0001). The most common AEs were diarrhea and constipation. Serum K+ remained ≥3.5 mEq/L in all patients; 5 patients developed serum magnesium <1.4 mg/dL, including 4 whose baseline magnesium was below the lower limit of normal.

CONCLUSION

Patiromer is equally effective and well tolerated when taken without food or with food, thereby offering the potential for dosing flexibility.