Comparable efficacy and safety between second-line and later-line nivolumab therapy for metastatic renal cell carcinoma

Background The aim of this study was to compare the efficacy and safety of nivolumab as second-line and later-line (third-line or thereafter) therapy in metastatic renal cell carcinoma (mRCC). Methods Sixty-seven patients who received nivolumab after the failure of at least one molecular-targeted therapy were evaluated. The patients were divided into two groups based on the line of nivolumab: second-line and later-line groups. Efficacy was assessed using progression-free survival and overall survival (OS) after nivolumab initiation, and objective response rate. Safety was assessed using the incidence of immune-related adverse events. These outcomes were compared between the second-line and later-line groups. Results Forty-two patients (62.7%) received nivolumab as second-line therapy. There was no significant difference in the progression-free survival (median: 5.06 vs. 6.28 months, p = 0.691) or objective response rate (35.7% vs. 32.0%, p = 0.757) between the second-line and later-line groups. The OS tended to be longer in the second-line group (not reached vs. 26.0 months, p = 0.118), and the rate of patients who received subsequent therapy after nivolumab failure was significantly higher in the second-line group (90.9% vs. 55.0%, p = 0.0025). There was no difference in the incidences of immune-related adverse events between the second-line and later-line groups (any grade: 54.8% vs. 48.0%, p = 0.592; grade >= 3: 19.1% vs. 20.0%, p = 0.924). Conclusions The efficacy of nivolumab did not deteriorate and the tolerability was also maintained even in later-line therapy. However, a tendency of longer OS and a higher chance of subsequent therapy after nivolumab failure were observed with nivolumab as second-line therapy.