Comparison of Sevelamer Hydrochloride With Colestimide, Administered Alone or in Combination With Calcium Carbonate, in Patients on Hemodialysis

Abstract:  Since hyperphosphatemia in hemodialysis patients can cause secondary hyperparathyroidism and promotes vascular calcification, serum phosphate (Pi) levels must be controlled by phosphate binders. Although sevelamer and colestimide are known as similar non-calcium, non-aluminum phosphate binders in hemodialysis patients, there are no studies that compare the effects of the two agents as either a monotherapy or in combination with calcium carbonate (CaCO3). We randomly allocated 62 hemodialysis patients with hyperphosphatemia to treatment with sevelamer (3.0 g/day) and colestimide (3.0 g/day). During the study, 35 subjects dropped out, leaving 13 in the sevelamer group and 14 in the colestimide group. After a 2-week CaCO3 washout, all subjects received the monotherapy for 4 weeks and then CaCO3 (3.0 g/day) was added for another 4 weeks. Serum corrected calcium levels tended to decrease in both groups during the washout period and monotherapy, but there was no significant difference between the two groups after the addition of CaCO3. Although the calcium × phosphorus product (Ca × P) in the two groups increased during the washout period, there was no significant change or difference between the two groups during monotherapy. However, the addition of CaCO3 significantly reduced serum Pi at Week 8 compared to that at Week 0 in both groups, and significantly lowered Ca × P only in the sevelamer group, but not in the colestimide group. In this short-term study, sevelamer and colestimide similarly ameliorated hyperphosphatemia, but the combination of sevelamer and CaCO3 was more effective than colestimide with CaCO3 in controlling the Ca × P product, and it may improve cardiovascular mortality in hemodialysis patients.