Pneumologie 2016; 70 - P212
DOI: 10.1055/s-0036-1572212

Efficacy, safety and predictive biomarker results from a randomized phase II study comparing atezolizumab vs. docetaxel in patients with advanced NSCLC (POPLAR)

A Rittmeyer 1, A Spira 2, K Park 3, J Mazieres 4, J Vansteenkiste 5, M Ballinger 6, D Waterkamp 6, M Kowanetz 6, L Fehrenbacher 7
  • 1Lungenfachklinik Immenhausen
  • 2Virginia Cancer Specialists, Pc
  • 3Samsung Medical Centre
  • 4Toulouse University Hospital
  • 5Uz Leuven
  • 6Genentech Inc.
  • 7Kaiser Permanente Medical Center

Background: In a Phase Ia clinical trial, atezolizumab (anti-PDL1) showed single-agent activity in NSCLC patients (pts) with the objective response rate (ORR) associated with PD-L1 expression on tumor-infiltrating immune cells (IC) and/or tumor cells (TC). Here we report results from the first randomized study comparing atezolizumab vs. docetaxel (doc) in unselected NSCLC pts with subgroup analyses by PD-L1-expression.

Methods: 287 previously-treated NSCLC pts were stratified by PD-L1 IC status, histology (squamous vs. nonsquamous) and number of prior lines of therapy (1 or 2) and randomized (1:1) to 1200 mg IV q3w atezolizumab (n = 144) or 75 mg/m2 IV q3w doc (n = 143). PD-L1 expression was centrally evaluated using an immunohistochemistry (IHC) assay based on the SP142 antibody; pts were scored as IC 0, 1, 2 or 3 and TC 0, 1, 2, or 3. The objectives of this study were to evaluate the efficacy and safety of atezolizumab as compared with doc. The primary efficacy endpoint was overall survival (OS) and secondary endpoints were progression-free survival (PFS) and ORR. These endpoints will be assessed in both PD-L1-selected and the ITT patient populations. OS and PFS will be compared between treatment arms using the log-rank test; Kaplan-Meier methodology will be used to estimate median OS and PFS for each treatment arm and construct survival curves. Cox regression proportional hazard models will be used to estimate hazard ratios. An estimate of ORR (overall response of partial or complete response per RECIST v1.1) and its 95% CI will be calculated using the Clopper-Pearson method for each treatment arm. The incidence and severity of adverse events will be recorded. Enrollment was completed in March 2014. An analysis of the primary endpoint will be performed in March 2015, with a minimum duration of follow-up of ≈ 11.5 mo. Results from the OS, PFS and ORR analyses for both the overall population and subgroups by IC and TC status will be presented. Demographic and safety data will be summarized.