A comparative study on nivolumab and axitinib as secondary treatment in patients with metastatic renal cell carcinoma: A multi-institutional retrospective study in Japan.

Objectives: When primary treatment has been inadequate, nivolumab and axitinib are often used as a secondary treatments for patients with metastatic renal cell carcinoma (mRCC). However, there have been few reports comparing the efficacy and safety of these drugs.

Methods: We retrospectively investigated 58 patients treated with nivolumab and 57 patients treated with axitinib as secondary treatment between April 2013 and December 2019. We then assessed the clinical efficacy and safety of the treatments in both groups.

Results: The most common primary therapy was sunitinib (61.7%). Both nivolumab and axitinib groups showed no significant differences in terms of the objective response rate and disease control rate (p = 0.280 and p = 0.518, respectively). Importantly, progression-free survival (PFS) and overall survival (OS) seemed to be similar in patients treated with nivolumab and axitinib (p = 0.527 and p = 0.266, respectively), irrespective of the objective response to primary therapy. Furthermore, a Cox proportional hazards model showed that pretreatment Karnofsky Performance Status was significantly associated with PFS and OS. Although the incidence of adverse events was significantly higher in the patients treated with axitinib, there was no significant difference in time to treatment failure between the two groups.

Conclusions: Nivolumab and axitinib showed similar clinical benefits as secondary treatment in patients with mRCC; thus, they should be an option in sequential therapy following treatment with tyrosine kinase inhibitors (TKIs). Future studies and feasible therapeutic biomarkers would help predict the clinical response to TKIs or immune checkpoint inhibitors in patients with mRCC.