Effectiveness of patiromer in the treatment of hyperkalemia in chronic kidney disease patients with hypertension on diuretics

Abstract

Objective: Recurrent hyperkalemia frequently limits use of renin-angiotensin-aldosterone system inhibitors (RAASi) in chronic kidney disease (CKD) patients with hypertension, diabetes, and/or heart failure. Patiromer is a sodium-free, nonabsorbed potassium (K)-binding polymer approved by the US Food and Drug Administration for the treatment of hyperkalemia. This post-hoc analysis of OPAL-HK examined the effectiveness and safety of patiromer in reducing serum K in hyperkalemic CKD patients on RAASi, with hypertension, receiving diuretic therapy versus those not on diuretics.

Methods: Depending on the degree of hyperkalemia at baseline, CKD patients with serum K from 5.1 to less than 6.5 mmol/l on RAASi (n = 243) were assigned to a patiromer of total dose 8.4 or 16.8 g, divided twice daily. Changes in serum K, and tolerability and safety were assessed over 4 weeks in patients on and not on diuretics.

Results: At baseline, 132 patients used diuretics and 111 were not on diuretics, mean age was 64.3 and 64.0 years, respectively, and 63 and 51% were men. Similar reductions in serum K were seen over 4 weeks in both subgroups. At week 4, serum K fell by -0.95 ± 0.04 mmol/l with any diuretic and -1.04 ± 0.05 mmol/l with no diuretic. Patiromer was well tolerated, with mild-to-moderate constipation reported as the most common adverse event (7.6 and 14.4% of patients on any diuretic or no diuretic, respectively). Hypokalemia (s-K <3.5 mEq/l) was reported in 2.3% of patients on any diuretic and in 3.7% not on diuretics.

Conclusion: The serum K-lowering efficacy and safety profile of patiromer in hyperkalemia patients with CKD was not compromised by diuretic therapy.

FIGURE 1

Study design for the initial treatment phase of OPAL-HK (single-blind, 4 weeks). (∗) Estimated glomerular filtration rate (eGFR) 15 to less than 60 ml/min per 1.73 m² (central lab value) (†) Based on local lab value. B.i.d., twice a day; CKD, chronic kidney disease; HK, hyperkalemia; K⁺, potassium; RAASi, renin–angiotensin–aldosterone system inhibitors.

FIGURE 2

Serum potassium decreased over 4 weeks in hyperkalemic patients on patiromer on and off diuretics. Six patients who had no postbaseline serum potassium measurement after day 3 were excluded (four from the group using diuretics and two from the group using no diuretics). ^∗P < 0.0001 versus baseline.