title: Time to response: comparison of fulvestrant and oral endocrine agents.
abstract: BACKGROUND
  The different pharmacokinetic profiles of the intramuscularly administered antioestrogen fulvestrant and oral endocrine treatments have led to speculation among some physicians that this could result in a delayed time to response (TTR) with fulvestrant.
  
  
  METHODS
  An analysis of TTR was performed on data from 2 phase III trials comparing fulvestrant and anastrozole as second-line treatments for postmenopausal women with advanced-stage, tamoxifen-resistant breast cancer.
  
  
  RESULTS
  In a combined analysis of the data from these trials, median TTR was 3.1 months (range, 0.9-33.1 months) for fulvestrant and 3 months (range, 0.7-20.2 months) for anastrozole, although responses were still being noted after 2-3 years of stable disease in some patients. Data were subsequently analyzed from 3 other randomized phase III trials of fulvestrant, anastrozole, and tamoxifen in postmenopausal women. Time to response was also similar between the 3 treatments in these additional analyses.
  
  
  CONCLUSIONS
  Time to response is similar between fulvestrant and oral endocrine treatments, despite pharmacokinetic differences.
authors.affiliation: Cookridge Hospital, Leeds, UK.
authors.forename: David
authors.initials: D
authors.lastname: Dodwell
authors.forename: John
authors.initials: J
authors.lastname: Pippen
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077384:Anastrozole; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D017326:Clinical Trials, Phase III as Topic; D018572:Disease-Free Survival; D019008:Drug Resistance, Neoplasm; D004958:Estradiol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D020847:Estrogen Receptor Modulators / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D000077267:Fulvestrant; D006801:Humans; D007273:Injections, Intramuscular; D008875:Middle Aged; D009367:Neoplasm Staging; D009570:Nitriles / Q000008:administration & dosage / Q000627:therapeutic use*; D017698:Postmenopause; D016032:Randomized Controlled Trials as Topic; D013629:Tamoxifen; D014230:Triazoles / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D018931:Antineoplastic Agents, Hormonal; D020847:Estrogen Receptor Modulators; D009570:Nitriles; D014230:Triazoles; D013629:Tamoxifen; D000077267:Fulvestrant; D000077384:Anastrozole; D004958:Estradiol