An assessment of cinacalcet HCl effects on bone histology in dialysis patients with secondary hyperparathyroidism

Clin Nephrol. 2008 Apr;69(4):269-78. doi: 10.5414/cnp69269.


Aims: Cinacalcet lowers plasma parathyroid hormone (PTH) levels in patients with secondary hyperparathyroidism (sHPT), but the bone histologic response has not been described. This prospective, double-blind, placebo-controlled trial assessed the effects of cinacalcet on bone histology and serum markers of bone metabolism in dialysis patients with sHPT.

Methods: Patients with intact PTH (iPTH) > or = 300 pg/ml were randomly assigned 2:1 to receive cinacalcet or placebo with concurrent vitamin D and/or phosphate binder therapy. Cinacalcet (30 - 180 mg/day) was used to achieve iPTH levels < or = 200 pg/ml. Bone biopsies were performed before and after one year of treatment.

Results: Baseline and end-of-study data were available from 32 patients (19 cinacalcet, 13 placebo). Baseline bone turnover was elevated in 27, reduced in 3 and normal in 2 patients. Serum bone-specific alkaline phosphatase (BSAP) and N-telopeptide (NTx) were elevated. Cinacalcet treatment decreased PTH and diminished activation frequency, bone formation rate/bone surface, and fibrosis surface/bone surface. Adynamic bone was observed in three patients receiving cinacalcet; in two of these, PTH levels were persistently low (< 100 pg/ml). The histomorphometric parameter changes in bone corresponded to PTH, BSAP and NTx reductions. Bone mineralization parameters remained normal.

Conclusions: Treatment with cinacalcet lowered PTH and reduced bone turnover and tissue fibrosis among most dialysis patients with biochemical evidence of sHPT.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / blood
  • Biopsy
  • Bone Density / drug effects
  • Bone Density Conservation Agents / therapeutic use*
  • Bone Remodeling / drug effects*
  • Chronic Kidney Disease-Mineral and Bone Disorder / blood
  • Chronic Kidney Disease-Mineral and Bone Disorder / drug therapy
  • Chronic Kidney Disease-Mineral and Bone Disorder / etiology
  • Cinacalcet
  • Double-Blind Method
  • Female
  • Fibrosis
  • Humans
  • Hyperparathyroidism, Secondary / complications
  • Hyperparathyroidism, Secondary / drug therapy*
  • Ilium / pathology
  • Kidney Failure, Chronic / physiopathology*
  • Kidney Failure, Chronic / therapy
  • Male
  • Middle Aged
  • Naphthalenes / therapeutic use*
  • Prospective Studies
  • Renal Dialysis*


  • Biomarkers
  • Bone Density Conservation Agents
  • Naphthalenes
  • Cinacalcet