Quality-adjusted survival with first-line cabozantinib or sunitinib for advanced renal cell carcinoma in the CABOSUN randomized clinical trial (Alliance)

Abstract

Background: Cabozantinib Versus Sunitinib as Initial Targeted Therapy for Patients With Metastatic Renal Cell Carcinoma of Poor or Intermediate Risk: The Alliance A031203 CABOSUN Trial (CABOSUN) was a randomized, open-label, phase 2 trial evaluating first-line cabozantinib versus sunitinib in patients with advanced renal cell carcinoma (aRCC). This post hoc analysis evaluated quality-adjusted survival using Quality-adjusted Time Without Symptoms of disease or Toxicity of treatment (Q-TWiST).

Methods: Survival plots for cabozantinib and sunitinib (650-day follow-up) were partitioned into 3 health states: time spent before disease progression without toxicity (TWiST; toxicity based on National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0] grade 3/4 adverse events), time spent before disease progression with toxicity (TOX; durations of adverse events based on published literature), and time after disease recurrence (relapse) or progression to death (REL). Q-TWiST was the sum of the mean time spent in each state, with each state weighted to reflect patient preferences (from 0 [worst] to 1 [best]) using utility scores. TWiST was always weighted as 1. Overall survival and time to disease progression were based on all randomized patients (157 patients); TOX was based on all randomized and treated patients (150 patients).

Results: Across all utility combinations tested, Q-TWiST was found to be longer with cabozantinib versus sunitinib (range of differences, +24 days to +137 days). Q-TWiST differences that were found to be statistically significant (+92 days [95% confidence interval, 5-178 days] to +137 days [95% confidence interval, 60-214 days]) were of a clinically meaningful effect size (≥80 days), and were based on utility values that included those considered relevant for patients with aRCC (REL utility weight of 0.355, TOX utility weight of 0-1, and TWiST utility weight of 1).

Conclusions: In patients with aRCC, first-line cabozantinib was found to provide longer quality-adjusted survival compared with sunitinib. These findings may help to inform clinical decision making.

Lay summary: Cabozantinib and sunitinib are drugs that are used to treat patients with advanced kidney cancer. Clinical trials have shown that cabozantinib offers benefits over sunitinib, giving patients more time before their cancer progresses. It is important that this additional time before disease progression does not come at the expense of patients' quality of life, which can be affected by treatment side effects and/or ongoing cancer symptoms. Both quantity and quality of life are central to optimal treatment. In the current analysis of patients with advanced kidney cancer who were initiating treatment for the first time, cabozantinib provided more quality time before cancer progression compared with sunitinib.

Keywords: carcinoma; protein tyrosine kinases; quality of life; renal cell.