New drugs for the treatment of hyperkalemia in patients treated with renin-angiotensin-aldosterone system inhibitors -- hype or hope?

Hyperkalemia (serum potassium >5.5 mmol/L) may result from increased potassium intake, impaired distribution between the intracellular and extracellular spaces, and/or reduced renal excretion. Renin-angiotensin-aldosterone system inhibitors (RAASIs) represent an important therapeutic strategy in patients with hypertension, heart failure, chronic kidney disease, and diabetes, but hyperkalemia is a key limitation to fully titrate RAASIs in these patients who are most likely to benefit from treatment. Thus, we need new drugs to control hyperkalemia in these patients while maintaining the use of RAASIs. We review two new polymer-based, non-systemic agents under clinical development, patiromer calcium and zirconium silicate, designed to increase potassium loss via the gastrointestinal tract for the management of hyperkalemia.