Phase II Study of Sunitinib Schedule in Metastatic Renal Cell Carcinoma


Key Points

  • Grade 3 fatigue, diarrhea, or hand-foot syndrome was observed in 25% of patients, with no grade 4 toxicity.
  • Treatment was discontinued due to adverse events in 10% of patients. 

In a phase II study reported in the Journal of Clinical Oncology, Jonasch et al found evidence that a 2-weeks-on/1-week-off (2/1) schedule of sunitinib (Sutent) might be an option in frontline treatment of metastatic renal cell carcinoma.

Study Details

In the study, 59 patients with previously untreated metastatic disease were enrolled between August 2014 and March 2016 and treated with sunitinib 50 mg per day on a 2/1 schedule; patients underwent schedule and dose alterations if toxicity developed.

The primary endpoint was < 15% grade ≥ 3 fatigue, diarrhea, or hand-foot syndrome (HFS), based on the hypothesis that the upper bound of the 95% confidence interval (CI) would fall below the reported 4-weeks-on/2-weeks-off schedule grade ≥ 3 toxicity rate of 25% to 30%. Overall, 77% of patients were at intermediate or poor risk.

Toxicity and Response

Median follow-up was 17 months. Overall, 25% (95% CI = 15.0%–38.4%) of patients experienced grade 3 fatigue, diarrhea, or HFS. Adverse events led to dose reduction in 37% of patients and discontinuation of treatment in 10%. The most common adverse events of any grade were fatigue (78%, 14% grade 3); diarrhea (76%, 8% grade 3); and HFS (54%, 5% grade 3). The only grade 4 adverse event observed was grade 4 neutropenia in 1 patient.

The overall response rate was 57%, median progression-free survival was 13.7 months, and median overall survival was not reached. At 12 weeks, Functional Assessment of Cancer Therapy-General scores decreased by 0% to 10% from baseline, with reductions being smaller in patients who remained on sunitinib for a longer duration.

The investigators concluded, “The primary endpoint of decreased grade 3 toxicity was not met; however, treatment with a 2/1 sunitinib schedule is associated with a lack of grade 4 toxicity, a low patient discontinuation rate, and high efficacy…[T]he acceptable toxicity and high efficacy shown here support the adoption of a 2/1 option in the management of patients with [metastatic renal cell carcinoma].”

The study was supported by Pfizer.

Eric Jonasch, MD, of the Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, is the corresponding author for the Journal of Clinical Oncology article. 

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.