Author of

• 25966

  +

  P3.12 - Small Cell Lung Cancer/NET (Not CME Accredited Session) (ID 978)

  • Event: WCLC 2018
  • Type: Poster Viewing in the Exhibit Hall
  • Track:
  • Presentations: 1
  • Moderators:
  • Coordinates: 9/26/2018, 12:00 - 13:30, Exhibit Hall

  • 27645

    +

    P3.12-06 - SLFN11 Expression and Efficacy of PARP Inhibitor Therapy in Extensive Stage Small Cell Lung Cancer: ECOG-ACRIN 2511 Study (ID 14113)

    12:00 - 13:30  |  Author(s): Gabriel L Sica
    • Abstract

    Background
    

    Veliparib (V),an oral small molecule inhibitor of poly (ADP) ribose polymerase (PARP) enhanced cytotoxic chemotherapy in preclinical models of small cell lung cancer (SCLC). The combination of V with cisplatin/etoposide (CE) doublet showed efficacy improvement as first-line therapy of extensive stage SCLC (ES-SCLC) with adjusted PFS HR: 0.63 1-sided p=0.01. There was differential treatment effect by strata (adjusted treatment HR comparing CE+V: CE: 0.34; 80% CI: 0.22 - 0.51; 1-sided p<0.001 for male patients with high tumor burden versus adjusted HR: 0.81 80% CI: 0.60 - 1.09; 1-sided p=0.18 for other patients subsets) highlighting the need to identify patient subset most likely to benefit. SLFN11 expression was previously shown to be associated with benefit of V when combined with temozolomide in relapsed SCLC and also predicted benefit of CE in preclinical models. We assessed the utility of SLFN11 as a predictive biomarker in the context of E2511 frontline clinical trial.

    a9ded1e5ce5d75814730bb4caaf49419 Method
    

    Archival tissue samples collected from patients with ES-SCLC enrolled and treated on E2511 study was employed for biomarker analysis looking at SLFN11 expression by immunohistochemistry. The study has 88% power to detect a PFS hazard ratio of 0.5 comparing SLFN11 (+) and (-) patients using a one-sided 0.025 level logrank test.

    4c3880bb027f159e801041b1021e88e8 Result
    

    There was an imbalance between control and experimental arms in the Male/abnormal LDH stratum (in strata) with respect to Age: p=0.006; malignant pleural effusion: p=0.095 and T stage: p=0.02. Median PFS was 5.1 mos on CE (95% CI 4.1-6.1) vs. 6.2 mos on CE+V (95% CI 5.9-8.8); HR=0.32, p=0.002 (unadjusted); median OS on CE was 8.8 mos (95% CI 6.6-11.1) vs. 9.5 mos on CE+V (95% CI 7.8-12.8); HR=0.76, p=0.39. Clinical outcome differences based on SLFN11 expression is ongoing and will be presented at the meeting.

    8eea62084ca7e541d918e823422bd82e Conclusion
    

    Pending ongoing analysis of correaltion of biomarker with clinical outcomes

    6f8b794f3246b0c1e1780bb4d4d5dc53