In Part A, participants who meet all eligibility criteria will initiate patiromer at an oral dose of 8.4 g (1 packet/day). The dose will be adjusted based on the serum potassium (sK+) levels.~After the completion of part A, all the participants who meet the eligibility criteria for Part B will be randomised to receive patiromer or placebo. Participants will start Part B with the same dose of patiromer they were receiving at the end Part A. However, Patiromer dose may be up- or down-titrated based on sK+ levels.~The primary objectives of the study are:~Part A - To evaluate the efficacy of patiromer for the treatment of hyperkalemia in Chinese subjects.~Part B - To evaluate the effect of withdrawing patiromer on sK+ control. To determine if the treatment with patiromer will result in continued use of renin-angiotensin-aldosterone system inhibitor (RAASi) medications.
This is a multicentre, 2-part, single-blind, randomised, withdrawal, placebo-controlled study, that includes a 4-week patiromer treatment phase (Part A) followed by an 8-week randomised placebo-controlled withdrawal phase (Part B) and a 2-week follow-up period.