IMpower150 Final Overall Survival Analyses for Atezolizumab Plus Bevacizumab and Chemotherapy in First-Line Metastatic Nonsquamous NSCLC

Introduction: We report the final overall survival (OS) analyses of atezolizumab-carboplatin-paclitaxel (ACP [experimental arm]) and OS data with approximately 39.8 months of median follow-up with atezolizumab-bevacizumabcarboplatin-paclitaxel (ABCP) versus bevacizumabcarboplatin-paclitaxel (BCP) in chemotherapy-naive patients with metastatic nonsquamous NSCLC in the phase 3 IMpower150 study (NCT02366143). Methods: In this randomized, open-label study (N = 1202), coprimary end points included investigator-assessed progression-free survival and OS in intention-to-treat (ITT) wild type (WT; no EGFR or ALK alterations) patients. Secondary and exploratory end points included OS in ITT and programmed death-ligand 1 (PD-L1) subgroups defined by the VENTANA SP142 and SP263 immunohistochemistry assays. Results: At the final analysis with ACP versus BCP (data cutoff: September 13, 2019; minimum follow-up: 32.4 mo), ACP had numerical, but not statistically significant, improvements in OS (ITT-WT: median OS = 19.0 versus 14.7 mo; hazard ratio = 0.84; 95% confidence interval: 0.71-1.00). OS benefit was sustained with ABCP versus BCP (ITT-WT: 19.5 versus 14.7 mo; hazard ratio = 0.80; 95% confidence interval: 0.67-0.95). Exploratory analyses in the SP142-defined PD-L1 subgroups revealed longer median OS with ABCP and ACP versus BCP in PD-L1-high and PD-L1-positive subgroups; in the PD-L1-negative subgroups, median OS was similar with ACP and ABCP versus BCP. Safety was consistent with that in earlier analyses (data cutoff: January 22, 2018). Conclusions: At the final IMpower150 OS analysis, ACP had numerical, but not statistically significant, OS improvement versus BCP. Updated data with an additional 20 months of follow-up revealed continued OS improvement with ABCP versus BCP in all patients. (c) 2021 International Association for the Study of Lung Cancer. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The final analysis of IMpower150 study showed a numerical OS improvement with ACP compared to BCP in metastatic nonsquamous NSCLC patients, while ABCP demonstrated continued OS improvement in all patients.