title: Prolonged efficacy of a single dose of the bisphosphonate zoledronic acid.
abstract: OBJECTIVE
  Bisphosphonates play a central role in the management of bone loss due to a range of disorders, including metastatic bone disease, cancer treatment-induced bone loss, and postmenopausal osteoporosis. With potent bisphosphonates, such as zoledronic acid, it may be possible to maintain efficacy with relatively infrequent administration.
  
  
  METHODS
  Sixty-six patients who were osteopenic at >1 year following curative cancer therapy received a single i.v. 4 mg dose of the bisphosphonate zoledronic acid. Bone mineral density (BMD) was measured using double-beam X-ray absorptiometry scan and the bone resorption marker N-telopeptide of type II collagen was determined using a chemiluminescence ELISA assay.
  
  
  RESULTS
  The single dose of zoledronic acid induced mean increases in bone BMD at the lumbar spine of 3.1%, 5.2%, and 5.3% and at the total hip of 2.7%, 3.5%, and 4.3% after 12, 24, and 36 months of follow-up, respectively (P < 0.001 at all time points). By 36 months, 84% of patients had achieved increase in BMD at the spine and 90% at the hip. The mean percentage decrease in the bone resorption marker N-telopeptide was approximately 58% at 6 weeks and 42%, 33%, and 31% at 12, 24, and 36 months, respectively (P < 0.001).
  
  
  CONCLUSIONS
  A single dose of zoledronic acid in patients with low BMD results in a sustained increase in BMD and a corresponding decrease in bone resorption. Very infrequent administration of zoledronic acid may have clinical benefits in terms of convenience, reduced toxicity, improved compliance, and cost.
authors: Academic Unit of Clinical Oncology, Weston Park Hospital, University of Sheffield, United Kingdom. J.E.Brown@leeds.ac.uk
authors: Janet E
authors: JE
authors: Brown
authors: Susan P
authors: SP
authors: Ellis
authors: James E
authors: JE
authors: Lester
authors: Sandra
authors: S
authors: Gutcher
authors: Tina
authors: T
authors: Khanna
authors: Om-Prakesh
authors: OP
authors: Purohit
authors: Eugene
authors: E
authors: McCloskey
authors: Robert E
authors: RE
authors: Coleman
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D015519:Bone Density; D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D001851:Bone Diseases, Metabolic / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000209:etiology; D001842:Bone and Bones / Q000000981:diagnostic imaging; D004164:Diphosphonates / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid