title: Erlotinib has moderate single-agent activity in chemotherapy-naïve castration-resistant prostate cancer: final results of a phase II trial.
abstract: OBJECTIVE
  To investigate the efficacy and toxicity of single-agent erlotinib in chemotherapy-naive castration-resistant prostate cancer.
  
  
  METHODS
  Eligible patients received erlotinib at 150 mg daily until disease progression. Toxicity was assessed every 2 weeks and responses every 8 weeks. Primary end point was assessing the overall clinical benefit measured as the sum of stable disease, partial response, and complete response. Secondary end points included time to disease progression, overall survival, and toxicity using the National Cancer Institute Common Toxicity Criteria version 3.0.
  
  
  RESULTS
  A total of 29 patients were enrolled in this study. Median age was 77 and median prostate-specific antigen was 66.3 ng/mL. Of 22 evaluable patients, 2 met the criteria for partial response and 5 demonstrated stable disease for an overall clinical benefit of 31%. PSA-doubling time improved in all responding patients to a median of 6 months from 3 months before entry into the study. One patient remained in study at 28 months, and 2 had > 50% decrease in their serum PSA level. Median time to disease progression was 2 months, but at 12 months, 9% of patients were progression-free. Median overall survival was 16.3 months, with 1- and 2-year survival rates of 58% and 27%, respectively. Erlotinib was well tolerated, with only 2 patients requiring dose reductions. Adverse events were as expected with grade 3 or 4 diarrhea, fatigue, and rash occurring in 10%, 6%, and 6% of patients, respectively.
  
  
  CONCLUSIONS
  Erlotinib has moderate activity in chemotherapy-naive castration-resistant prostate cancer, with some patients showing biochemical response. Future studies investigating this agent in combination are warranted. (This trial was registered at http://NCI.gov, NCT00272038).
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, Oncology Specialists, Lutheran General Hospital, Park Ridge, IL 60068, USA. cnabhan@oncmed.net
authors.forename: Chadi
authors.initials: C
authors.lastname: Nabhan
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Lestingi
authors.forename: Angel
authors.initials: A
authors.lastname: Galvez
authors.forename: Kathy
authors.initials: K
authors.lastname: Tolzien
authors.forename: Susan K
authors.initials: SK
authors.lastname: Kelby
authors.forename: Dean
authors.initials: D
authors.lastname: Tsarwhas
authors.forename: Steven
authors.initials: S
authors.lastname: Newman
authors.forename: Jacob D
authors.initials: JD
authors.lastname: Bitran
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D000069347:Erlotinib Hydrochloride; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D011799:Quinazolines / Q000627:therapeutic use*
chemical_list: D000726:Androgen Antagonists; D011799:Quinazolines; D000069347:Erlotinib Hydrochloride; D066246:ErbB Receptors