Alfacalcidol in the therapy of renal bone disease

Parathyroid hormone increases due to hypocalcemia even in the early phases of renal insufficiency. At the same time, hyperphosphatemia develops due to decreasing renal excretion which, in turn, intensifies secondary hyperparathyroidism. The cornerstones for prevention and therapy of renal osteopathy are, therefore, efficient lowering of phosphate levels and the early substitution of vitamin-D3 metabolites. In a post marketing surveillance (PMS) of almost 2,000 dialysis patients with renal osteopathy, the course of therapy with Alfacalcidol (Bondiol) was observed over a 6-month period. In 55.9% of cases, Alfacalcidol was administered at a daily dose of 0.25 microg. In 26.6% of patients, Alfacalcidol was administered every second day at a dose of 0.25-1 microg/d. In 16.1% of patients, Alfacalcidol was administered as pulse-therapy, mostly at a dose of 1-2 microg once or twice per week. To lower phosphate levels, 54.8% of patients received calcium compounds, 9.2% aluminium compounds, and 21.7% aluminium compounds in combination with calcium compounds. 14.3% of patients did not receive phosphate binding agents. Two thirds of patients had received active vitamin-D3-metabolites prior to commencing therapy with alfacalcidol, most frequently calcitrol. In 58.1%, the dialysis solution used had a calcium concentration of 1.5 mmol/l (44.8%) or lower; whereas in 41.9%, a higher calcium concentration was used--mostly 1.75 mmol/l (3 8%). During the observation period, serum concentrations of calcium and phosphate remained constant, suggesting that the risk of hypercalcemia due to therapy with Alfacalcidol was not increased. It was found that elevated alkaline phosphatase and parathyroid hormone levels could be significantly lowered (statistically). These effects could be observed both in patients who had been previously treated with vitamin-D3-metabolites and in patients without prior therapy. Efficacy and tolerability of therapy with Alfacalcidol was assessed to be very high by the attending nephrologists.