title: Randomized trial comparing pulse calcitriol and alfacalcidol for the treatment of secondary hyperparathyroidism in haemodialysis patients.
abstract: OBJECTIVE
  Calcitriol and alfacalcidol are used extensively for the treatment of secondary hyperparathyroidism. Unfortunately, there is limited published data comparing the efficacy and tolerability of both active vitamin D sterols. This study was undertaken to determine whether calcitriol provides a therapeutic advantage to alfacalcidol.
  
  
  METHODS
  This was a randomized, active controlled study. Patients with intact parathyroid hormone (iPTH) >32 pmol/L were randomized to receive orally calcitriol or alfacalcidol after each haemodialysis for up to 24 weeks. Reduction of PTH, changes of plasma albumin-corrected calcium and phosphorus were analysed. The initial dose of alfacalcidol was twice that of calcitriol.
  
  
  RESULTS
  Sixteen patients were randomized into each group. At baseline, plasma albumin-corrected calcium, phosphorus and PTH were no different between groups. At 24 weeks, PTH changes were -50.8 ± 31.8% and -49.4 ± 32.5% from the baseline in the calcitriol and alfacalcidol groups, respectively (P = 0.91). The patients who achieved target PTH of 16-32 pmol/L were 82% in the calcitriol and 67% in the alfacalcidol group (P = 0.44). Plasma albumin-corrected calcium and phosphorus were not significantly different but showed trends toward gradually increasing from baseline in both groups (calcium, 6.0 ± 7.2% vs 10.9 ± 6.5% (P = 0.10); phosphorus, 13.0 ± 29.4% vs 16.7 ± 57.2% (P = 0.83) in calcitriol and alfacalcidol, respectively). The mean dose of calcitriol and alfacalcidol were 4.1 and 6.9 µg/week, respectively (P < 0.0001).
  
  
  CONCLUSIONS
  Alfacalcidol can be used to control secondary hyperparathyroidism at doses of 1.5-2.0 times that of calcitriol. The two drugs are equally efficacious and lead to similar changes in calcium and phosphorus.
authors.affiliation: Division of Nephrology, Department of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. tekkt@mahidol.ac.th
authors.forename: Kraiwiporn
authors.initials: K
authors.lastname: Kiattisunthorn
authors.forename: Kittikarn
authors.initials: K
authors.lastname: Wutyam
authors.forename: Artit
authors.initials: A
authors.lastname: Indranoi
authors.forename: Somkiat
authors.initials: S
authors.lastname: Vasuvattakul
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D057966:Calcimimetic Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D002117:Calcitriol / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D006887:Hydroxycholecalciferols / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D011446:Prospective Studies; D020551:Pulse Therapy, Drug; D006435:Renal Dialysis; D013785:Thailand; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D057966:Calcimimetic Agents; D006887:Hydroxycholecalciferols; C470125:PTH protein, human; D010281:Parathyroid Hormone; D010710:Phosphates; D002117:Calcitriol; D002118:Calcium; C008088:alfacalcidol