Health-related quality of life in patients with metastatic renal cell carcinoma treated with sunitinib vs interferon-α in a phase III trial: final results and geographical analysis

BACKGROUND: In a randomised phase III trial, sunitinib significantly improved efficacy over interferon-α (IFN-α) as first-line therapy for metastatic renal cell carcinoma (mRCC). We report the final health-related quality of life (HRQoL) results. METHODS: Patients (n=750) received oral sunitinib 50 mg per day in 6-week cycles (4 weeks on, 2 weeks off treatment) or subcutaneous IFN-α 9 million units three times weekly. Health-related quality of life was assessed with nine end points: the Functional Assessment of Cancer Therapy–General and its four subscales, FACT–Kidney Symptom Index (FKSI-15) and its Disease-Related Symptoms subscale (FKSI-DRS), and EQ-5D questionnaire's EQ-5D Index and visual analogue scale. Data were analysed using mixed-effects model (MM), supplemented with pattern-mixture models (PMM), for the total sample and the US and European Union (EU) subgroups. RESULTS: Patients receiving sunitinib reported better scores in the primary end point, FKSI-DRS, across all patient populations (P<0.05), and in nine, five, and six end points in the total sample, in the US and EU groups respectively (P<0.05). There were no significant differences between the US and EU groups for all end points with the exception of the FKSI item ‘I am bothered by side effects of treatment’ (P=0.02). In general, MM and PMM results were similar. CONCLUSION: Patients treated with sunitinib in this study had improved HRQoL, compared with patients treated with IFN-α. Treatment differences within the US cohort did not differ from those within the EU cohort.