Researchers at ZymoGenetics, Inc. announced positive final results from a phase 2 clinical trial in patients receiving second or third-line therapy for advanced renal cell carcinoma with the combination of recombinant Interleukin 21 (IL-21) and Nexavar® (sorafenib) tablets. The combination demonstrated considerable clinical benefit, with an overall response rate of 21 percent, a disease-control rate of 82 percent, and progression-free survival of 5.7 months in this heavily pretreated population. Investigators presented the results at this week's American Society of Clinical Oncology annual meeting.
“These results add to the case for efficacy and safety of IL-21 when used with Nexavar in patients previously treated for renal cell cancer and point to a meaningful benefit of IL-21 when used in combination with a targeted therapy,” said Dr. John Thompson of the Seattle Cancer Care Alliance, who was the overall principal investigator and whose group enrolled about half of the patients. “The combination of IL-21 with Nexavar could be a promising treatment for renal cell cancer, particularly for patients after failure of prior therapies.”
Researchers enrolled 33 patients in the open-label, multi-center phase 2 clinical trial conducted at 14 sites in the U.S. and Canada. Study endpoints were safety, tumor response, criteria, and progression-free survival. Tumor response was assessed both by the investigator and by independent radiologic review.
The independent review of tumor response, completed for 33 patients, showed seven confirmed partial response (21 percent), one unconfirmed partial response (3 percent), 19 stable disease (58 percent), four progressive disease (12 percent), and two unevaluable patients, for an overall disease-control rate of 82 percent. Median progression-free survival was 5.7 months or 24.6 weeks. The final phase 2 results in renal cell cancer indicated that IL-21 combined with Nexavar was well tolerated and is associated with meaningful anti-tumor activity both in terms of tumor response and duration of disease control in patients who have failed prior therapy for advanced renal cell cancer.
[Adapted from a news release from ZymoGenetics, Inc.]