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Samantha Moe
Lori D Wazny
Janet E Martin


Vitamin D analogues, alfacalcidol, calcitriol, secondary hyperparathyroidism, renal dialysis



Secondary hyperparathyroidism  is a common complication in patients with chronic kidney disease and treatment with vitamin D analogues is a mainstay of therapy. Although oral calcitriol and alfacalcidol are used extensively in Canada, there is little published data comparing equal doses of these agents.



To compare the effect of equal doses of oral calcitriol and alfacalcidol on intact parathyroid hormone concentrations (iPTH) in the treatment of secondary hyperparathyroidism due to chronic kidney disease.

Secondary endpoints included serum 1,25-dihydroxyvitamin  D3, calcium and phosphate concentrations, achievement of target iPTH concentrations, and need for phosphate binder dose increases.



Five adult hemodialysis subjects who were naïve to vitamin D analogues and had iPTH concentrations ³

20 pmol/L were enrolled  in a prospective,  randomized  16-week  crossover  pilot study.  Subjects  were randomized to either oral calcitriol or oral alfacalcidol 0.75 mcg three times weekly for six weeks. After a four-week washout period, patients were crossed over to the alternate drug for six weeks.



Oral calcitriol significantly suppressed iPTH after six weeks of therapy (p=0.003), while no significant change in iPTH was observed with oral alfacalcidol.



This small randomized crossover study provides preliminary evidence that equal doses of oral alfacalcidol and calcitriol  may demonstrate  differences  in iPTH suppression  during the first six weeks in dialysis patients treated for secondary hyperparathyroidism. Further comparative trials are required to confirm this finding and to determine whether important differences in parathyroid hormone suppression exist between

oral calcitriol and alfacalcidol beyond the six-week period.

Abstract 3968 | PDF Downloads 984


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