Introduction to sevelamer hydrochloride and its clinical effects.

Sevelamer hydrochloride (SH) is widely used for the treatment of hyperphosphatemia in patients with renal failure who are on maintenance hemodialysis. In this study, we investigated the clinical effects of SH, administered as either monotherapy or combined with a calcium carbonate formulation, on the metabolism of calcium (Ca) and phosphorus (P) in patients who had been taking a Ca-based binder. Patients were divided into three groups (i): switched completely from a Ca-based binder to SH (complete switch); (ii) dosage of the Ca-based binder was reduced, and SH introduced (partial switch); and (iii) dosage of the Ca-based binder was not reduced and SH introduced (combination therapy). We also examined the effects of the introduction of SH on the lipid profile and parathyroid hormone (PTH) concentration. Comparison between groups of the numbers of successfully treated cases (reaching target concentrations of serum P=5.5 mg/dL and Ca x P product=55 mg2/dL2 within 6 months of treatment) showed that the likelihood of reaching target levels was higher if Ca-based binder was maintained as much as possible (combination therapy>partial changeover>complete changeover). Furthermore, treatment with SH decreased total cholesterol and non-HDL cholesterol concentrations significantly, and also increased HDL cholesterol and PTH concentrations compared to pre-treatment. These results suggest that when a calcium carbonate formulation is already in use, as far as compliance allows, the dosage should not be reduced when SH is added. Despite its beneficial effects on the lipid and PTH concentrations, preventing an excessive increase in the PTH concentration is essential when using SH.