Feasibility of sequential use of sunitinib and temsirolimus in advanced renal cell carcinoma

Targeted agents sunitinib and temsirolimus are effective in advanced renal cell carcinoma. Treatment algorithms for single-agent use have been proposed in order to optimize timing and type of therapy. The aim of this study was to investigate the tolerability and adverse event profile of patients who received sunitinib and temsirolimus in sequence. We performed a retrospective analysis of patients with advanced renal cell carcinoma who received temsirolimus after disease progression under sunitinib therapy. Dosages of both drugs were in accordance with the recommendations given by the respective manufacturers. Temsirolimus was provided before its official approval within a compassionate use program. Adverse event assessment followed the National Cancer Institute Common Toxicity Criteria. Thirteen patients receiving temsirolimus after progression under sunitinib were identified. Overall treatment time with targeted drugs (sunitinib/temsirolimus) was 34.8 (17-78) weeks, treatment with sunitinib was 28.6 (12-72), and with temsirolimus 6.2 (2-16) weeks, respectively, whereas mean therapy interruption time between both approaches was 4.4 (2-12) weeks. Under sunitinib, we observed 52 transient adverse events, 49 (94.2%) were of grade I/II, whereas 3 (5.8%) were of grade III. Under temsirolimus 36 adverse events, only grade I/II in nature were remarked. Sequential use of temsirolimus after progression under sunitinib seems to be feasible and results in a predictable, medically manageable side effect profile. Further evaluation is necessary to define the oncological validity of this sequencing approach.