Relypsa Inc., of Redwood City, Calif., said one-year data from the phase II AMETHYST-DN trial of patiromer for oral suspension (FOS), published in the Journal of the American Medical Association, showed that patients with chronic kidney disease and mild or moderate hyperkalemia who were treated with the potassium binder had statistically significant decreases in blood potassium levels from baseline at four weeks, the primary endpoint (p < 0.001).