Oral Potassium Binder Comparison: KBINDER Trial Interim Analysis

Patients with hyperkalemia face increased rates of cardiovascular events and prolonged hospital stays. The KBINDER (K Binders in Emergency Room and Hospitalized Patients) clinical trial is a head-to-head evaluation of oral potassium binders (cation-exchange resins) for the treatment of acute hyperkalemia (NCT04585542).

During a poster session at the NKF Spring Clinical Meetings 2023, Hayden Troutt, MPH, and colleagues presented interim analysis from 26 participants of the KBINDER trial. The poster was titled Comparison of Oral Potassium Binders in Acute Hyperkalemia.

The trial randomized emergency department and hospitalized patients who presented with serum potassium ≥5.5 mEq/L to receive sodium polystyrene sulfonate (SPS), patiromer, sodium zirconium cyclosilicate (SZC), or nonspecific laxative control polyethylene glycol (PEG). Patients with history of bowel surgery, ileus, diabetic ketoacidosis, or pregnancy were excluded.

The pragmatic study design allowed for temporizing measures such as use of insulin/dextrose, albuterol nebulizer, or loop diuretic per discretion of the attending physician. Change in serum potassium from baseline was determined via laboratory tests 2 hours and 4 hours after treatment. Analysis of variance was used to determine mean change in potassium across groups.

Mean age of the cohort was 59 years and 41% were female. At baseline, mean serum potassium was 5.68 mEq/L. There were no statistically significant differences in the effect of oral potassium binder treatment at each timepoint. At 4 hours after treatment, the change in potassium was –0.07 (PEG, n=6), –0.92 (SPS, n=5), –0.63 (patiromer, n=8), and –0.3 (SZC, n=7).

In summary, the authors said, “In interim analyses of the KBINDER trial, there was no statistical difference in acute potassium lowering between the oral cation-exchange resins in acute hyperkalemia patients. Enrollment for the trial is ongoing.”

Source: Troutt H, Canas A, Darwish A, Kalantar-Zadeh K, Lau WL. Comparison of oral potassium binders in acute hyperkalemia. Poster #303. Abstract of a poster presented at the National Kidney Foundation Spring Clinical Meetings 2023; April 11-15, 2023; Austin, Texas.