title: Pharmacokinetic evaluation of  toremifene  and its clinical implications for the treatment of osteoporosis.
abstract: BACKGROUND
  Toremifene is a triphenylethylene selective estrogen receptor modulator (SERM) that differs from tamoxifen in a single chloride ion addition on a side chain, resulting in a potentially more favorable toxicity profile.
  
  
  METHODS
  This article reviews the pharmacokinetics of toremifene and its potential use for the treatment of osteoporosis. This article was based on articles found through a literature search containing the terms 'toremifene' and 'SERMs.'
  
  
  CONCLUSIONS
  Toremifene can be administered orally with an excellent bioavailability. The overall pharmacokinetic profile is remarkably similar to tamoxifen. Toremifene is highly metabolized in the liver and is eliminated primarily in the feces following enterohepatic circulation. Some of its metabolites retain biological activity. This SERM was approved by the FDA for the treatment of estrogen receptor-positive metastatic breast cancer and is under investigation for its potential skeletal benefits in men on androgen deprivation therapy. Despite the positive preclinical and clinical evidences for the prevention of bone loss and fractures, the chemopreventive effect on prostate cancer remains to be confirmed and an increased risk of venous thromboembolism was evidenced in a large Phase III trial. Thus, additional data are required to establish the full clinical profile of this compound and its potential advantages over antiresorptive agents commonly in use for the treatment of osteoporosis.
authors.affiliation: University of Siena, Department of Internal Medicine, Endocrine-Metabolic Sciences and Biochemistry, Policlinico Le Scotte 53100-Siena, Italy. gennari@unisi.it
authors.forename: Luigi
authors.initials: L
authors.lastname: Gennari
authors.forename: Daniela
authors.initials: D
authors.lastname: Merlotti
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Stolakis
authors.forename: Ranuccio
authors.initials: R
authors.lastname: Nuti
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy; D017326:Clinical Trials, Phase III as Topic; D005260:Female; D006801:Humans; D008099:Liver / Q000378:metabolism; D008297:Male; D010024:Osteoporosis / Q000188:drug therapy*; D011471:Prostatic Neoplasms / Q000517:prevention & control; D016032:Randomized Controlled Trials as Topic; D011960:Receptors, Estrogen / Q000187:drug effects / Q000378:metabolism; D020845:Selective Estrogen Receptor Modulators / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D013923:Thromboembolism / Q000139:chemically induced / Q000453:epidemiology; D017312:Toremifene / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*
chemical_list: D011960:Receptors, Estrogen; D020845:Selective Estrogen Receptor Modulators; D017312:Toremifene