title: Zoledronic acid significantly reduces skeletal complications compared with placebo in Japanese women with bone metastases from breast cancer: a randomized, placebo-controlled trial.
abstract: OBJECTIVE
  To investigate the efficacy and safety of zoledronic acid for the treatment of bone metastases from breast cancer.
  
  
  METHODS
  Women with bone metastases (N = 228) were randomly assigned to receive 4 mg zoledronic acid (n = 114) or placebo (n = 114) via 15-minute infusions every 4 weeks for 1 year. The primary efficacy end point was the skeletal-related event (SRE) rate ratio between treatment groups. An SRE was defined as pathologic fracture, spinal cord compression, and radiation or surgery to bone. Secondary end points included percentage of patients with at least one SRE, time-to-first SRE, and Andersen-Gill multiple-event analysis.
  
  
  RESULTS
  The SRE rate ratio at 1 year (excluding HCM and adjusted for prior fracture) was 0.61 (permutation test; P = .027), indicating that zoledronic acid reduced the rate of SRE by 39% compared with placebo. The percentage of patients with at least one SRE (excluding HCM) was significantly reduced by 20% by zoledronic acid (29.8% v 49.6% for placebo; P = .003). Zoledronic acid significantly delayed time-to-first SRE (median not reached v 364 days; Cox regression; P = .007) and reduced the risk of SREs by 41% in multiple event analysis (risk ratio = 0.59; P = .019) compared with placebo. Zoledronic acid was well tolerated with a safety profile similar to placebo. No patient treated with zoledronic acid had grade 3 or 4 serum creatinine increase.
  
  
  CONCLUSIONS
  Zoledronic acid significantly reduced skeletal complications compared with placebo across multiple end points in Japanese women with bone metastases from breast cancer.
authors.affiliation: Department of Surgery, Hyogo Medical Center for Adults, 13-70 Kitaojicho Akashi 673-0021, Japan. norio@tiger.interq.or.jp
authors.forename: Norio
authors.initials: N
authors.lastname: Kohno
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Aogi
authors.forename: Hironobu
authors.initials: H
authors.lastname: Minami
authors.forename: Seigo
authors.initials: S
authors.lastname: Nakamura
authors.forename: Taro
authors.initials: T
authors.lastname: Asaga
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Iino
authors.forename: Toru
authors.initials: T
authors.lastname: Watanabe
authors.forename: Carsten
authors.initials: C
authors.lastname: Goessl
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohashi
authors.forename: Shigemitsu
authors.initials: S
authors.lastname: Takashima
mesh_terms: D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary*; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D004164:Diphosphonates / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000627:therapeutic use*; D007262:Infusions, Intravenous; D007564:Japan; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012016:Reference Values; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome; D000077211:Zoledronic Acid
chemical_list: D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid