Sevelamer with and without calcium and vitamin D: observations from a long-term open-label clinical trial.

OBJECTIVE

To determine the effects of sevelamer hydrochloride on serum phosphorus, calcium, calcium x phosphate product, and parathyroid hormone (PTH) in patients treated with and without vitamin D metabolites and calcium supplementation.

DESIGN

Long-term, open-label clinical trial.

SETTING

Hemodialysis units.

PATIENTS: One hundred ninety-two adult patients with end-stage renal disease on hemodialysis.

INTERVENTION: An extended treatment period of sevelamer hydrochloride, preceded and followed by phosphate binder washout periods.

MAIN OUTCOME MEASURES: Treatment-related changes in serum phosphorus, calcium, calcium x phosphate product, and PTH.

RESULTS

Subjects treated with sevelamer alone, sevelamer with vitamin D metabolites (with or without calcium), and sevelamer with calcium without vitamin D experienced significant reductions in mean serum phosphorus (range, 2.1 to -2.9 mg/dL) and the calcium x phosphate product (range, -16.3 to -23.4 mg2/dL2). The mean serum calcium concentration increased in all subgroups except those treated with sevelamer alone (range, +0.3 to +0.5 mg/dL). In contrast, only subjects treated concurrently with vitamin D metabolites experienced a reduction in PTH. Subjects treated with sevelamer alone or sevelamer with calcium without vitamin D experienced an increase in PTH with treatment.

CONCLUSION

Sevelamer hydrochloride is a safe and effective phosphate binder in hemodialysis patients. Sevelamer should be used in combination with vitamin D metabolites to jointly control hyperphosphatemia and hyperparathyroidism. Randomized clinical trials will be required to determine the optimal management strategies for metabolic bone disease in end-stage renal disease, as well as less advanced stages of chronic renal insufficiency.