Randomized phase II trial of sunitinib on an intermittent versus continuous dosing schedule as first-line therapy for advanced renal cell carcinoma

Purpose: Sunitinib has shown antitumor activity with a manageable safety profile as metastatic renal cell carcinoma (RCC) treatment, when given by the standard intermittent schedule as well as a continuous daily dosing (CDD) schedule. A trial was conducted to compare the schedules. Patients and Methods: Patients with treatment-naive, clear cell advanced RCC were randomly assigned 1:1 to receive sunitinib 50 mg/d for 4 weeks followed by 2 weeks off treatment (schedule 4/2; n = 146) or 37.5 mg/d on the CDD schedule (n = 146) for up to 2 years. The primary end point was time to tumor progression. Results: Median time to tumor progression was 9.9 months for schedule 4/2 and 7.1 months for the CDD schedule (hazard ratio, 0.77;95%CI, 0.57 to 1.04; P=.090). No significant difference was observed in overall survival (23.1 v 23.5 months; P = .615), commonly reported adverse events, or patient-reported kidney cancer symptoms. Schedule 4/2 was statistically superior to CDD in time to deterioration, a composite end point of death, progression, and disease-related symptoms (P = .034). Conclusion: There was no benefit in efficacy or safety for continuous dosing of sunitinib compared with the approved 50 mg/d dose on schedule 4/2. Given the numerically longer time to tumor progression with the approved 50 mg/d dose on schedule 4/2, adherence to this dose and schedule remains the treatment goal for patients with advanced RCC.