title: Phase II study of erlotinib for acquired resistance to gefitinib in patients with advanced non-small cell lung cancer.
abstract: BACKGROUND
  Gefitinib and erlotinib are used to treat advanced non-small cell lung cancer (NSCLC). Gefitinib is a common first-line treatment, but most patients develop resistance. This phase II study evaluated the efficacy of erlotinib after acquired resistance to gefitinib.
  
  
  METHODS
  Between January 2008 and September 2009, we enrolled 50 patients with advanced NSCLC who had received one or more chemotherapy regimens, including gefitinib monotherapy to which they had partial responses (PR) or stable disease (SD). Erlotinib (150 mg) was administered until disease progression or unacceptable toxicity. Patients were 11 males, 39 females; median age 65 years (range=36-81 years); 46 with adenocarcinoma; performance status 0/1/2: 24/19/7; and smoking status, never/former/current: 33/15/2. Prior gefitinib response, PR/SD: 36/14. Median duration of prior gefitinib therapy was 419 days (range=63-1,540 days). Median interval after gefitinib therapy was 29 days (range=13-1,198 days).
  
  
  RESULTS
  Of 47 patients on erlotinib, four showed PR and 29 showed SD [response rate, 8.5%; disease control rate (DCR), 70.2%]. DCR for patients who continued gefitinib treatment for more than one year was significantly higher (81.5%) than for patients who could not continue (57.1%; p=0.018); but was not affected by prior gefitinib response or treatment interval. Median tiMETo treatment failure: 100 days (95% confidence interval=90-110 days); median overall survival: 342 days (95% confidence interval=242-442 days). Rash (78%) and diarrhea (68%) were the most common adverse reactions; grade 5 pneumonitis occurred in one patient (2%).
  
  
  CONCLUSIONS
  Erlotinib treatment after gefitinib failure may prolong the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors treatment.
authors.affiliation: Department of Thoracic Medical Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan. mnishio@jfcr.or.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Horiike
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Hisashi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Noriko
authors.initials: N
authors.lastname: Yanagitani
authors.forename: Keita
authors.initials: K
authors.lastname: Kudo
authors.forename: Fumiyoshi
authors.initials: F
authors.lastname: Ohyanagi
authors.forename: Akira
authors.initials: A
authors.lastname: Ono
authors.forename: Tateaki
authors.initials: T
authors.lastname: Naito
authors.forename: Haruyasu
authors.initials: H
authors.lastname: Murakami
authors.forename: Takeshi
authors.initials: T
authors.lastname: Horai
authors.forename: Makoto
authors.initials: M
authors.lastname: Nishio
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D015415:Biomarkers / Q000378:metabolism; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology*; D019008:Drug Resistance, Neoplasm; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D000069347:Erlotinib Hydrochloride; D005260:Female; D000077156:Gefitinib; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D047428:Protein Kinase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D011799:Quinazolines / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D015415:Biomarkers; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D000069347:Erlotinib Hydrochloride; D066246:ErbB Receptors; D000077156:Gefitinib
keywords: EGFR mutation; Non-small cell lung cancer; erlotinib; gefitinib; phase II study; resistance