Author of

• 31515

  +

  P2.14 - Targeted Therapy (ID 183)

  • Event: WCLC 2019
  • Type: Poster Viewing in the Exhibit Hall
  • Track: Targeted Therapy
  • Presentations: 1
  • Moderators:
  • Coordinates: 9/09/2019, 10:15 - 18:15, Exhibit Hall

  • 31579

    +

    P2.14-59 - Osimertinib in EGFR T790M Advanced NSCLC: Analysis of Uncommon/Complex EGFR Mutations in a Real-World Study (ASTRIS) (ID 1263)

    10:15 - 18:15  |  Author(s): Antonio Passaro
    • Abstract
    • Slides

    Background
    

    The challenges of treating uncommon/complex EGFR mutations impact treatment decisions in clinical practice. Osimertinib is a third-generation, irreversible, oral EGFR-TKI that potently and selectively inhibits both EGFR-TKI sensitising (EGFRm) and EGFR T790M mutations and has demonstrated efficacy in NSCLC CNS metastases. ASTRIS is an ongoing, international, real-world study of osimertinib in EGFR T790M positive advanced NSCLC (NCT02474355). We report a subset-analysis of patients with uncommon/complex mutations.

    Method
    

    Patients with stage IIIB/IV T790M positive NSCLC previously treated with an EGFR-TKI were enrolled and received osimertinib 80 mg once-daily. Progression-free survival (PFS), clinical response and time to treatment discontinuation (TTD) were analysed in both full analysis set (FAS) and patients with uncommon/complex EGFR mutations. Uncommon mutation combinations included: T790M+G719X, T790M+S768I, T790M+ex20ins; complex mutations included T790M+two or more mutation(s).

    Result
    

    From 18 September 2015 to 15 October 2018 data cut-off, 3015 patients across 16 countries had received ≥1 dose of osimertinib (FAS), 53(2%) of these patients had uncommon/complex EGFR mutations. Baseline demographics between this patient subset and the FAS were similar (Asian: 55%/69%; female: 57%/64%; median age: 59 [30–80] years/62 [range, 27–92]; WHO performance status 2: 9%/11%, respectively). Baseline EGFR mutation status at enrolment of the FAS is shown in Table 1. Clinical outcomes appeared to be lower in the uncommon/complex mutation subset than in the FAS: response rate (measured in a FAS subset with ≥1 documented response assessment) was 50% [95% CI, 35.2, 64.8] in the uncommon/complex mutation group, and 57% [55.2, 58.9] in the FAS; median PFS was 8.1 [5.4, 10.1] and 11.1 [11.0, 12.0] months; median TTD was 9.0 [6.7, 11.5] and 13.5 [12.6, 13.9] months, respectively. Overall survival data are immature.

    

    Conclusion
    

    Whilst clinical outcomes appeared to be lower in the uncommon/complex mutation subset than the FAS, they were favourable and support use of osimertinib 80mg in this heterogeneous population.

    Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.