Safety and efficacy of sevelamer in the treatment of uncontrolled hyperphosphataemia of haemodialysis patients.

Background/aim: The treatment of hyperphosphataemia is of major importance in the management of patients on dialysis. Traditional phosphate binders can be associated with undesirable effects. Recently, a new non-absorbable phosphate-binding polymer, sevelamer hydrochloride, has been available. Clinical information is scarce, and its cost could be a limiting factor for its wider use. No studies have evaluated its usefulness in uncontrolled hyperphosphataemic patients.

Methods: We identified 34 patients with a maintained serum phosphorus concentration >6.5 mg/dl and/or toxicity related to standard phosphorus-binding treatment (aluminium or calcium based). Sevelamer was added and titrated up fortnightly to achieve phosphorus control. Previous phosphate binders were decreased, whenever possible. The period of the study was 6 months.

Results: Thirteen patients (38%) dropped out because of side effects, mainly related to the gastro-intestinal tract. The efficacy analysis disclosed that the phosphorus concentration decreased from 2.39 +/- 0.48 to 1.84 +/- 0.48 mmol/l (p < 0.001). The mean dose of sevelamer was stabilised at 3.4 +/- 1.8 g/day. The amount of calcium- and aluminium-based phosphate binders could be decreased from 5.1 +/- 3.5 to 3.1 +/- 2.7 g/day (38% decrease) and from 2.4 +/- 1.5 to 1.5 +/- 1.7 g/day (36% decrease), respectively. The Ca x P product was significantly decreased from 5.83 +/- 1.19 to 4.36 +/- 1.12 mmol/l2 (p < 0.001). The total cholesterol concentration decreased from 4.34 +/- 0.9 to 3.98 +/- 0.9 mmol/l (p < 0.01) and the low-density lipoprotein cholesterol level from 2.61 +/- 0.98 to 2.20 +/- 0.77 mmol/l (p < 0.03).

Conclusions: Sevelamer is an effective phosphate binder that allows a better serum phosphorus control, while allowing a decrease in the dose of calcium- and aluminium-based phosphate binders in these difficult patients. The drawbacks are the high intolerance rate and the price of the product.