Phase I Study of the Pharmacodynamics and Safety of Sodium Zirconium Cyclosilicate in Healthy Chinese Adults.

Sodium zirconium cyclosilicate (SZC) is an effective potassium binder for patients with hyperkalemia. This single-center, open-label, phase I study (NCT03283267) characterized the pharmacodynamics and safety of SZC in Chinese individuals. Twenty-two healthy Chinese adults (mean age, 33.5 years) randomized 1:1 received daily oral SZC 5 or 10 g for 4 days, following 4 days on a low-sodium, high-potassium diet (continued throughout the study). End points were mean change from baseline in 24-hour urinary potassium (primary) and sodium excretion, and serum potassium concentration. Urinary potassium excretion significantly decreased with SZC 5 g (mean change [mmol], -13.0; P < .001) and 10 g (-15.4; P < .001). Although urinary sodium excretion decreased significantly with SZC 5 g (-11.5; P = .030), there was no significant change with SZC 10 g (-5.1; P = .299). Serum potassium concentrations decreased significantly with SZC 5 g (-0.14; P = .031) and 10 g (-0.20; P = .002). All treatment-emergent adverse events were mild, and none were considered causally related to SZC. Over 4 days, the pharmacodynamics and safety of SZC were consistent in healthy Chinese adults with global studies and patients of Japanese ethnicity.