Three-year follow-up results from phase II studies of nivolumab in Japanese patients with previously treated advanced non-small cell lung cancer: Pooled analysis of ONO-4538-05 and ONO-4538-06 studies

Background: Nivolumab is a programmed cell death 1 (PD-1) receptor inhibitor antibody that enhances immune system antitumor activity. It is associated with longer overall survival (OS) than the standard treatment of docetaxel in patients with previously treated advanced squamous (SQ) and non-squamous (non-SQ) non-small cell lung cancer (NSCLC). We previously conducted two phase II studies of nivolumab in Japanese patients with SQ (ONO-4538-05) and non-SQ (ONO-4538-06) NSCLC, showing overall response rates (ORRs) (95% CI) of 25.7% (14.2-42.1) and 22.4% (14.5-32.9), respectively, with acceptable toxicity. In this analysis, we more precisely estimated the long-term safety and efficacy in patients with SQ and non-SQ NSCLC by pooling data from these two trials. Methods: SQ (N = 35) and non-SQ (N = 76) NSCLC patients received nivolumab (3 mg/kg, every 2 weeks) until progression or discontinuation. OS was estimated using the Kaplan–Meier method. A pooled analysis of SQ and non-SQ patients was also performed. Results: In SQ NSCLC patients, the median OS (95% CI) was 16.3 months (12.4-25.2), and the estimated 1-year, 2-year, and 3-year survival rates were 71.4% (53.4-83.5), 37.1% (21.6-52.7), and 20.0% (8.8-34.4), respectively. In non-SQ NSCLC patients, median OS was 17.1 months (13.3-23.0), and the estimated 1-, 2-, and 3-year survival rates were 68.0% (56.2-77.3), 37.4% (26.5-48.1), and 31.9% (21.7-42.5), respectively. When SQ NSCLC and non-SQ NSCLC data were pooled, the median OS was 17.1 months (14.2-20.6), and the estimated 1-, 2-, and 3-year survival rates were 69.1% (59.6-76.8), 37.3% (28.3-46.2), and 28.1% (20.0-36.7), respectively. Twenty (76.9%) of 26 responders lived for 3 or more years. Nivolumab was well tolerated and no new safety signals were found. Conclusion: Treatment with nivolumab improved long-term survival and was well tolerated in patients with SQ and non-SQ NSCLC. Trial registration: JapicCTI-132072; JapicCTI-132073.