New Treatment Option for HYPERKALEMIA: patiromer

This First Report Managed Care Treatment Innovations highlights 2 studies. Weir et al looks at the efficacy and safety of Veltassa (patiromer) in patients with chronic kidney disease (CKD) receiving renin-angiotensin-aldosterone system (RAAS) inhibitors, while Bakris et al evaluates patiromer over 52 weeks in hyperkalemic patients with CKD and type 2 diabetes taking RAAS inhibitors.

TWO STUDIES SHOW PATIROMER EFFECTIVE IN POTASSIUM LOWERING

Among patients with CKD and hyperkalemia who were taking at least 1 RAAS inhibitor, OPAL-HK (A Two-Part, Single-Blind, Phase 3 Study Evaluating the Safety and Efficacy of Patiromer for the Treatment of Hyperkalemia) found that treatment with patiromer was associated with a reduction in serum potassium levels and, as compared with placebo, a reduction in the recurrence of hyperkalemia.

The study had 2 phases—a 4-week, single-group, single-blind treatment phase and an 8-week, placebo-controlled, single-blind, randomized, withdrawal phase. In the initial treatment phase, 243 patients were assigned to 1 of 2 patiromer starting doses (at an initial dose of 4.2 g or 8.4 g twice daily) according to hyperkalemia severity. Patiromer significantly decreased potassium levels from baseline to week 4 (-1.01 ± 0.03 mEq/L; P<.001). At 4 weeks, 76% of patients had potassium levels in the target range (3.5-<5.1 mmol/L). Subsequently, 107 patients were randomly assigned to patiromer or placebo for the second phase of the study. During this phase, patients taking patiromer had no change in median potassium from baseline (0.00 mEq/L), whereas potassium levels significantly increased in the placebo group (0.72 mEq/L). Hyperkalemia recurred in more patients who were switched to placebo versus the patiromer treatment arm through week 8 (60% vs 15%, respectively). Mild-to-moderate constipation was the most common adverse event (AE) reported in 11% of patients.

The effect of treatment with patiromer for up to 52 weeks was evaluated in AMETHYST-DN (RLY5016 in the Treatment of Hyperkalemia in Patients With Hypertension and Diabetic Nephropathy). The phase 2, open-label, dose-ranging, randomized trial included 304 hyperkalemic patients with CKD and type 2 diabetes mellitus on RAAS inhibitor therapy. Patients were stratified by baseline serum potassium level into mild or moderate hyperkalemia groups and randomly assigned in a 1:1:1 ratio to 1 of 3 patiromer doses (mild hyperkalemia: 4.2 g, 8.4 g, or 12.6 g twice daily; moderate hyperkalemia: 8.4 g, 12.6 g, or 16.8 g twice daily).