Frequency of pre-treatment may not increase the immune-related adverse events of RCC patients treated with nivolumab.

Nivolumab has shown good prognosis in renal cell carcinoma (RCC) patients previously treated with targeted therapy. We aimed to study irAE (immune-related adverse event) due to nivolumab and numbers of previous treatment lines in RCC patients. Between October 2016 and November 2019, 114 patients were treated with nivolumab as second- and later-line therapy. Among them, 110 patients with complete data were evaluated in this retrospective observational study. The primary endpoint was the relation between irAE and numbers of previous targeted therapies. Secondary endpoints were the relation of irAE with the duration of nivolumab treatment and with best overall response. For the primary analysis, proportional odds logistic regression was used to assess the effect of the number of prior therapies on the grade of any irAE as the ordinal variable. For the secondary analysis, binomial logistic regression models adjusted for the covariates were prepared to confirm the association between the incidence of irAE and the number of courses, number of nivolumab treatments and best overall response. Overall, 69, 66, 33, 13, 9 and 9 patients were treated with sunitinib, axitinib, pazopanib, sorafenib, temsirolimus and everolimus, respectively, prior to nivolumab. In total, 60 adverse events (Grade 1, 21; Grade 2, 21; Grade 3, 14; Grade 4, 2; not evaluated, 2) were identified in the patients treated with nivolumab. Ordered logistic regression analysis showed that the adjusted odds ratios of numbers of prior treatment for grade of irAE were 1.12 (numbers of prior treatment: 2 to 1) and 1.31 (3 to 1). Odds ratios of the numbers of nivolumab treatments and best overall response for the incidence of irAE were not significant. No statistically significant relations were found between grade of irAE and numbers of treatments prior to nivolumab. Patients treated with nivolumab should be closely monitored for irAE regardless number of previous therapies.