Researchers performed a long-term analysis of previous study data, comparing the effects on quality of life for patients with renal cell carcinoma treated with either cabozantinib or everolimus.
Results of the analysis were published in the Journal of Clinical Oncology (online January 29, 2018; doi:10.1200/JCO.2017.75.2170).
The phase III METEOR trial examined 658 patients previously treated with advanced renal cell carcinoma who were randomly assigned (1:1) to receive cabozantinib or everolimus. Patients in the cabozantinib arm demonstrated improved progression-free survival, overall survival, and objective response rate compared with those in the everolimus arm.
David Cella, PhD, Northwestern University Feinberg School of Medicine (Chicago, IL), and colleagues conducted a further analysis of the METEOR trial to assess changes in quality of life as an exploratory endpoint for patients in each treatment arm. Patients completed the 19-item Functional Assessment of Cancer Therapy-Kidney Symptom Index (FKSI-19) and the five-level EuroQol (EQ-5D-5L) questionnaires at baseline and throughout the study. Researchers also utilized the nine-item FKSI-Disease-Related Symptoms (FKSI-DRS), a subset of FKSI-19.
Resulting data were summarized descriptively and by repeated-measures analysis. A clinically relevant difference was pre-defined as an effect size of ≥ 0.3. Researchers also measured time to deterioration, which was defined as the earlier date of death, radiographic progressive disease, or ≥ 4-point decrease from baseline in FKSI-DRS.
Researchers noted that the quality of life questionnaire completion rates remained ≥ 75% through week 48 in each treatment arm.
Results of the analysis showed no difference over time for FKSI-19, FKSI-DRS, or EQ-5D data between the treatment arms. While cabozantinib was associated with worse diarrhea and nausea in the FKSI-19 questionnaire, everolimus was associated with worse shortness of breath. These differences are consistent with the adverse event profile of each drug, researchers noted.
Importantly, cabozantinib was found to improve time to deterioration overall, with a particularly marked improvement in patients with bone metastases at baseline.
Dr Cella and colleagues concluded that cabozantinib generally maintained long-term quality of life when compared with everolimus in patients with advanced renal cell carcinoma. The extended time to deterioration overall, especially in patients with bone metastases, makes cabozantinib the superior option for quality of life in this population, they wrote.—Zachary Bessette