Clinical Outcomes of First-line Sunitinib Followed by Immuno-oncology Checkpoint Inhibitors in Patients With Metastatic Renal Cell Carcinoma

Limited data are available on how the first-line duration can affect clinical outcomes observed after subsequent immuno-oncology treatment among patients with metastatic renal cell carcinoma. The present retrospective cohort study of 161 patients found that the first-line sunitinib duration might have a minimal effect on subsequent immuno-oncology therapy effectiveness. These findings could aid healthcare practitioners in the treatment decision process for sequencing therapies. Background: The present retrospective, longitudinal cohort study assessed the association between the first-line sunitinib treatment duration and clinical outcomes with second-line immuno-oncology (IO) therapy among patients with metastatic renal cell carcinoma (mRCC). Patients and Methods: A total of 161 patients with mRCC who had been treated with first-line sunitinib and subsequent IO therapy from select International mRCC Database Consortium centers were included. The overall survival, time to next therapy, time to treatment discontinuation, and real-world physician-assessed best response measured from IO therapy initiation were analyzed and compared between patients treated with first-line sunitinib for >= 6 months and those treated for < 6 months. Results: The 116 patients treated with sunitinib for >= 6 months tended to be older and to have a better International mRCC Database Consortium risk than the 45 patients treated for < 6 months (favorable, 36% vs. 8%, P = .001; intermediate, 59% vs. 70%, P = .21; poor, 5% vs. 22%, P = .007). The receipt of sunitinib for >= 6 months versus < 6 months was associated with longer survival (hazard ratio [HR], 0.42; 95% confidence interval [CI], 0.21-0.87; P = .02). No significant association was observed between the first-line sunitinib duration and second-line IO outcomes, including the time to next therapy (HR, 0.89; 95% CI, 0.52-1.51; P = .66), time to treatment discontinuation (HR, 0.85; 95% CI, 0.54-1.34; P = .49), and tumor response (odds ratio, 0.73; 95% CI, 0.22-2.49; P = .62). Conclusions: We found no statistically significant association between the first-line sunitinib duration and clinical outcomes with second-line IO therapy. Patients receiving first-line sunitinib for > 6 months compared with < 6 months was associated with better overall survival, although potential unadjusted confounders could have been present. These findings support the paradigm that previous therapy will not dictate the effectiveness of subsequent immunotherapy. (C) 2019 Elsevier Inc. All rights reserved.