Atezolizumab Monotherapy and Consequent Therapy With Atezolizumab Plus Bevacizumab for NSCLC

This is a single-arm phase II trial to evaluate the efficacy and safety of atezolizumab and bevacizumab combination therapy (stage 2) after radiologic progression of atezolizumab monotherapy (stage 1) in Korean patients with locally advanced or metastatic NSCLC who have progressed during or following a platinum-containing regimen. Initially, patients will be treated with Atezolizumab 1200mg every 3 weeks as a single agent (stage 1). After radiologic progression from atezolizumab monotherapy, patients will be consequently treated with atezolizumab (1200mg every 3 weeks) and combination with bevacizumab (15mg/kg every 3 weeks). Exploratory biomarkers will be observed in order to identify predictive biomarkers correlated to response and to evaluate the changes of local and systemic immune profile between baseline and at the time of progression.