CheckMate 171: A Phase 2 Trial of Nivolumab in Patients with Previously Treated Advanced Squamous Non-small Cell Lung Cancer, Including ECOG PS 2 and Elderly Populations

Background: CheckMate 171 (NCT02409368) is an open-label, multicentre, phase 2 trial of nivolumab in previously treated advanced squamous non-small cell lung cancer (NSCLC), conducted as part of a post-approval commitment to the European Medicines Agency (EMA). We report outcomes from this trial.

Methods: Patients with Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2 and disease progression during/after ≥1 systemic treatment (≥1 being platinum-based chemotherapy) for advanced or metastatic disease were treated with nivolumab 3 mg/kg every 2 weeks until progression or unacceptable toxicity. The primary end-point was incidence of grade 3-4 treatment-related select adverse events (AEs). Other end-points included overall survival (OS) and safety.

Results: Of 811 patients treated, 103 had ECOG PS 2; 278 were aged ≥70 years and 125 were ≥75 years of age. Minimum follow-up was ~18 months. Safety was similar across populations; the most frequent grade 3-4 treatment-related select AEs in all treated patients were diarrhoea (1%), increased alanine aminotransferase (ALT, 1%), pneumonitis (0.7%), colitis (0.6%) and increased aspartate aminotransferase (AST, 0.5%). Median OS was similar in all treated patients and those aged ≥70 and ≥75: 10.0 months, 10.0 months and 11.2 months, respectively. Median OS was 5.2 months in patients with ECOG PS 2.

Conclusion: These results suggest that nivolumab is well tolerated and active in patients with advanced, relapsed squamous NSCLC, including the elderly, with OS outcomes consistent with phase 3 data. In patients with ECOG PS 2, nivolumab had similar tolerability, but outcomes were worse, as expected in this difficult-to-treat, poor prognosis population.

Clinical Trial Registration: NCT02409368.