title: Lapatinib and trastuzumab in combination with an aromatase inhibitor for the first-line treatment of metastatic hormone receptor-positive breast cancer which over-expresses human epidermal growth factor 2 (HER2): a systematic review and economic analysis.
abstract: BACKGROUND
  Breast cancer is the uncontrolled, abnormal growth of malignant breast tissue affecting predominantly women. Metastatic breast cancer (mBC) is an advanced stage of the disease when the disease has spread beyond the original organ. Hormone receptor status and human epidermal growth factor 2 (HER2) status are two predictive factors that are taken into consideration when estimating the prognosis of patients with breast cancer.
  
  
  OBJECTIVE
  To review the clinical effectiveness and cost-effectiveness evidence base for lapatinib (LAP) in combination with an aromatase inhibitor (AI) and trastuzumab (TRA) in combination with an AI for the first-line treatment of patients who have hormone receptor-positive (HR+)/human epidermal growth factor 2-positive (HER2+) mBC.
  
  
  METHODS
  Relevant electronic databases and websites, including MEDLINE, EMBASE and the Cochrane Library, were searched until May 2010. Further data were derived from the manufacturers' submissions for LAP + AI and TRA + AI.
  
  
  METHODS
  A systematic review of the clinical effectiveness and cost-effectiveness of LAP + AI and TRA + AI was undertaken. As it was deemed inappropriate to compare LAP + AI with TRA + AI, two separate assessments of cost-effectiveness versus AIs alone were undertaken.
  
  
  RESULTS
  Three trials were included in the systematic review [the patient populations of the efficacy and safety of lapatinib combined with letrozole (EGF30008) trial, the efficacy and safety of trastuzumab combined with anastrozole (TAnDEM) trial and the efficacy and safety of letrozole combined with trastuzumab (eLEcTRA) trial]. As a result of differences in the exclusion criteria and because one trial was halted prematurely, comparisons across trials were believed to be inappropriate and meta-analysis was not possible. Individually, however, the findings from the trials all suggest that LAP + AI or TRA + AI results in improved progression-free survival and/or time to progression when compared with AIs alone. The trials do not show a statistically significant benefit in terms of overall survival. Two separate economic analyses were conducted based on the completed trials; neither LAP + AI nor TRA + AI was found to be cost-effective when compared with AI monotherapy.
  
  
  CONCLUSIONS
  Because of differences in the EGF30008 and the TAnDEM trials, the Assessment Group believes the indirect comparisons analyses conducted by the manufacturers are inappropriate and, for the same reason, chooses not to compare LAP + AI with TRA + AI in an economic evaluation.
  
  
  CONCLUSIONS
  LAP + AI and TRA + AI appear to be clinically more effective than AI monotherapy, but neither is cost-effective compared with AIs alone. It was not possible to compare LAP + AI with TRA + AI. Future research should include research into treating mBC in the HR+/HER2+ population who are not TRA (or LAP) naive and into comparing the clinical effectiveness of AIs as monotherapy in patients with HER2+ and human epidermal growth factor 2-negative breast cancer.
  
  
  BACKGROUND
  The National Institute for Health Research Technology Assessment programme.
authors.affiliation: Liverpool Reviews and Implementation Group, University of Liverpool, Liverpool, UK.
authors.forename: N
authors.initials: N
authors.lastname: Fleeman
authors.forename: A
authors.initials: A
authors.lastname: Bagust
authors.forename: A
authors.initials: A
authors.lastname: Boland
authors.forename: R
authors.initials: R
authors.lastname: Dickson
authors.forename: Y
authors.initials: Y
authors.lastname: Dundar
authors.forename: M
authors.initials: M
authors.lastname: Moonan
authors.forename: J
authors.initials: J
authors.lastname: Oyee
authors.forename: M
authors.initials: M
authors.lastname: Blundell
authors.forename: H
authors.initials: H
authors.lastname: Davis
authors.forename: A
authors.initials: A
authors.lastname: Armstrong
authors.forename: N
authors.initials: N
authors.lastname: Thorp
mesh_terms: D000077384:Anastrozole; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage* / Q000191:economics; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000191:economics / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D002986:Clinical Trials as Topic; D003362:Cost-Benefit Analysis; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D000077341:Lapatinib; D000077289:Letrozole; D009570:Nitriles / Q000008:administration & dosage* / Q000191:economics; D011799:Quinazolines / Q000008:administration & dosage* / Q000191:economics; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors; D000068878:Trastuzumab; D014230:Triazoles / Q000008:administration & dosage* / Q000191:economics
chemical_list: D000077384:Anastrozole; D061067:Antibodies, Monoclonal, Humanized; D000077341:Lapatinib; D000077289:Letrozole; D009570:Nitriles; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; D014230:Triazoles