• Effect of Patiromer on Hyperkalemia Recurrence in Older Chronic Kidney Disease Patients Taking RAAS Inhibitors

      Weir, M.R.; Bushinsky, D.A.; Benton, W.W. (Elsevier Inc., 2018)
      Background: Older people are predisposed to hyperkalemia because of impaired renal function, comorbid conditions, and polypharmacy. Renin-angiotensin-aldosterone system inhibitors (RAASi), which are recommended to treat chronic kidney disease and heart failure augment the risk. Patiromer, a nonabsorbed potassium binder, was shown in the phase 3 OPAL-HK study to decrease serum potassium in patients with chronic kidney disease taking RAASi. We studied the efficacy and safety of patiromer in a prespecified subgroup of patients aged ≥65 years from OPAL-HK. Methods: Chronic kidney disease patients with mild or moderate-to-severe hyperkalemia received patiromer, initially 8.4 g/d or 16.8 g/d, respectively, for 4 weeks (treatment phase, part A). Eligible patients entered an 8-week randomized withdrawal phase (part B) and continued patiromer or switched to placebo. Results: Mean ± standard error change in serum potassium from baseline to week 4 of part A (primary endpoint) in patients aged ≥65 years was −1.01 ± 0.05 mEq/L (P <.001); 97% achieved serum potassium 3.8-<5.1 mEq/L. The serum potassium increase during the first 4 weeks of part B was greater in patients taking placebo than in those taking patiromer (P <.001). Fewer patients taking patiromer (30%) than placebo (92%) developed recurrent hyperkalemia (serum potassium ≥5.1 mEq/L). Mild-to-moderate constipation occurred in 15% (part A) and 7% (part B) of patients aged ≥65 years. Serum potassium <3.5 mEq/L and serum magnesium <1.4 mg/dL were infrequent (4% each in patients aged ≥65 years in part A). Conclusions: Patiromer reduced recurrent hyperkalemia and was well tolerated in older chronic kidney disease patients taking RAASi. Copyright 2018 The Authors
    • Long-term effects of patiromer for hyperkalaemia treatment in patients with mild heart failure and diabetic nephropathy on angiotensin-converting enzymes/angiotensin receptor blockers: Results from AMETHYST-DN

      Pitt, B.; Bakris, G.L.; Weir, M.R. (Wiley-Blackwell, 2018)
      Aims: Chronic kidney disease (CKD) in heart failure (HF) increases the risk of hyperkalaemia (HK), limiting angiotensin‐converting enzyme inhibitor (ACE‐I) or angiotensin receptor blocker (ARB) use. Patiromer is a sodium‐free, non‐absorbed potassium binder approved for HK treatment. We retrospectively evaluated patiromer's long‐term safety and efficacy in HF patients from AMETHYST‐DN. Methods and results: Patients with Type 2 diabetes, CKD, and HK [baseline serum potassium >5.0–5.5 mmol/L (mild) or >5.5–<6.0 mmol/L (moderate)], with or without HF (New York Heart Association Class I and II, by investigator judgement), on ACE‐I/ARB, were randomized to patiromer 8.4–33.6 g to start, divided twice daily. Overall, 105/304 (35%) patients had HF (75%, Class II). Mean (standard deviation) ejection fraction (EF) was 44.9% (8.2) (n = 81) in patients with HF; 26 had EF ≤40%. In HF patients, mean serum potassium decreased by Day 3 through Week 52. At Week 4, estimated mean (95% confidence interval) change in serum potassium was −0.64 mmol/L (−0.72, −0.55) in mild and −0.97 mmol/L (−1.14, −0.80) in moderate HK (both P < 0.0001). Most HF patients with mild (>88%) and moderate (≥73%) HK had normokalaemia at each visit from Weeks 12 to 52. Three HF patients were withdrawn because of high (n = 1) or low (n = 2) serum potassium. The most common patiromer‐related adverse event was hypomagnesaemia (8.6%). Conclusions: In patients with a clinical diagnosis of HF, diabetes, CKD, and HK on ACE‐I/ARB, patiromer was well tolerated and effective for HK treatment over 52 weeks. Copyright 2018 The Authors.