Sunitinib dosing schedule 2/1 improves tolerability, efficacy, and health-related quality of life in Chinese patients with metastatic renal cell carcinoma.

PURPOSE To assess the efficacy and tolerability of sunitinib dosing schedule of 2 weeks on and 1 week off (schedule 2/1) vs. the traditional schedule of 4 weeks on and 2 week off (schedule 4/2) and its influence on health-related quality of life (HRQoL) in Chinese patients with metastatic renal cell carcinoma (mRCC). MATERIALS AND METHODS A retrospective analysis of 108 patients with mRCC who were treated with sunitinib regimens (50mg daily) between January 2009 and July 2013 was undertaken. Overall, 3 groups of patients were studied according to the dosing schedule they received: schedule 4/2 (n = 50), transitional schedule 2/1 (T2/1; patients switched from schedule 4/2 to 2/1; n = 26), and initial schedule 2/1 (I2/1; n = 32). The tumor response, progression-free survival (PFS) time, adverse events, and HRQoL were assessed and compared among the groups. RESULTS The incidences of diarrhea, fatigue, hand-foot syndrome, and neutropenia induced by the treatment of sunitinib were all significantly less common with schedule I2/1 and T2/1 than with schedule 4/2 (P<0.05). Although there was no statistically significant difference in the tumor response among the 3 groups, the median PFS time was significantly longer with schedule I2/1 than with schedules T2/1 and 4/2 (11.2 vs. 9.4 and 9.5mo, respectively, P = 0.030), and HRQoL (as determined by 19-item Functional Assessment of Cancer Therapy Kidney Symptom Index scores) was better. CONCLUSIONS Treatment with sunitinib 50mg daily using a 2/1 dosing schedule can provide better tolerability and a longer PFS with better HRQoL in Chinese patients with mRCC than the traditional schedule 4/2.