There's A New Binder On the Block: FDA Approves Patiromer

BETHESDA, MD — The US Food and Drug Administration (FDA) has approved a new oral option for reversing hyperkalemia, patiromer. Patiromer is an oral suspension (Veltassa, Relypsa) that has just come out of the phase-2 AMETHYST-DN study, which  showed that daily administration of the potassium-binding agent safely controlled hyperkalemia over a 1 year in patients with type-2 diabetes and hypertension. They had entered with mild-to-moderate hyperkalemia secondary to treatment with renin-angiotensin-aldosterone system (RAAS)-inhibiting drugs. A phase 3 study hasalso been conducted in which patiromer demonstrated consistent efficacy ( N Engl J Med. 2015;372:211-221). This drug, along with ZS-9 (by ZS Pharma) which is also under investigation at this time, mean that we can completely forget about Kayexlate (which I mentioned before in Has kaeyexlate finally pooped out?).  Patiromer works by binding potassium in the gastrointestinal tract, decreasing its absorption. Its most common reported adverse effects are hypomagnesemia, diarrhea, nausea, abdominal discomfort, and flatulence. So now that we can control the hyperkalemia in patients with diabetes on RAAS blockade we may be able to finally titrate up to full therapeutic doses in those previously unable to tolerate higher doses (especially in the patient with diabetes and Type 4 RTA with hyperkalemia).
-Adrian Baudy