Author of

• 18374

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  P3.02b - Poster Session with Presenters Present (ID 494)

  • Event: WCLC 2016
  • Type: Poster Presenters Present
  • Track: Advanced NSCLC
  • Presentations: 1
  • Moderators:
  • Coordinates: 12/07/2016, 14:30 - 15:45, Hall B (Poster Area)

  • 18489

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    P3.02b-115 - Clinical Activity of Osimertinib in EGFR Mutation Positive Non Small Cell Lung Cancer (NSCLC) Patients (Pts) Previously Treated with Rociletinib (ID 4893)

    14:30 - 14:30  |  Author(s): A. Varga
    • Abstract

    Background:
    Both osimertinib and rociletinib were developed to target the EGFR resistance mutation T790M. Sequist, et al reported clinical activity with osimertinib in 9 pts previously treated with rociletinib[1]. We conducted a retrospective analysis at 8 institutions of pts treated with rociletinib, who discontinued the drug due to disease progression or intolerable toxicity and subsequently received osimertinib.
    
    Methods:
    We identified pts treated with rociletinib followed by osimertinib, as part of osimertinib's US expanded access program or via commercial supply. Clinical characteristics and outcomes were assessed. Frequency of clinical and radiologic assessments on osimertinib was at the discretion of the treating physician. For this retrospective review, reverse KM method was used to calculate the median follow-up; KM method was used for time-to-event endpoints.
    
    Results:
    45 pts were included in this analysis. Median age at the start of osimertinib was 66 years (43-86) and 71% were female. 28 pts had exon 19 deletions and 16 had L858R. Median duration of therapy on front line EGFR TKI was 18 months (5-54). Median starting dose of rociletinib was 625 mg bid (range 500-1000). The response rate (RR) and disease control rate (DCR; Response+Stable Disease) with rociletinib were 38% and 91%; median duration of rociletinib therapy was 6.2 months. 32 (71%) pts discontinued rociletinib for disease progression. 23 (51%) pts received other therapies (1-4) before starting osimertinib. 25 (56%) pts were known to have brain metastases at osimertinib initiation. RR and DCR with osimertinib were 33% and 82%. DCR in the brain was 88%. With a median follow-up of 7.1 months, median duration of osimertinib therapy in all patients was 8 months (95%CI- 6.6-NR; 64% censored). The 1-year overall survival (OS) rate on osimertinib was 70% (54%-91%). In the 32 pts who discontinued rociletinib due to progression, DCR with osimertinib was 75% and median duration of therapy was 7.8 months (4.6-NR). Neither duration of,or response to rociletinib treatment, nor interval between the two the drugs was associated with duration of osimertinib or OS after osimertinib using a Cox model adjusted for age and sex.
    
    Conclusion:
    Osimertinib can provide clinical benefit in EGFR mutation positive NSCLC patients previously treated with rociletinib. The clinical activity of osimertinib in these patients may be related to more potent inhibition of T790M mutation or ability to overcome resistance to rociletinib. Reference- 1. Sequist, et al. JAMA Oncology 2016