The FDA approved of Opdivo for metastatic squamous nonsmall cell lung cancer was based on a randomized, open-label study enrolling 272 patients with metastatic squamous NSCLC who had experienced disease progression during or after one prior platinum doublet-based chemotherapy regimen. Patients received Opdivo administered intravenously at 3 mg/kg every 2 weeks or docetaxel administered intravenously at 75 mg/m2 every 3 weeks. This study included patients regardless of their PD-L1 status. The first tumor assessments were conducted 9 weeks after randomization and continued every 6 weeks thereafter. The major efficacy outcome measure was overall survival (OS). The trial demonstrated a statistically significant improvement in OS for patients randomized to Opdivo as compared with docetaxel at the prespecified interim analysis when 199 events were observed (86% of the planned number of events for final analysis). The median survival was 9.2 months versus 6.0 months for the Opdivo versus docetaxel arms, respectively.