A phase II study of everolimus in combination with imatinib for previously treated advanced renal carcinoma

Purpose: This phase II study evaluated the activity of combined treatment with the mTOR inhibitor everolimus and the PDGFR inhibitor imatinib in patients with previously-treated, advanced renal carcinoma. The primary endpoint was estimation of the 3-month progression-free rate. Patients and methods: Eligible patients had metastatic or unresectable clear cell renal carcinoma, at least one prior systemic therapy, no prior mTOR inhibitor therapy, performance status 0-2, and measurable disease. Treatment consisted of everolimus 2.5 mg p.o. daily and imatinib 600 mg p.o. daily. The primary endpoint was the 3-month progression-free rate. Results: The study was closed after the first 19 patients because of an insufficient number of patients who were progression-free at 3 months. The 3-month progression-free rate was 49% (95% C.I. 23%, 72%) and the median progression-free survival was 2.9 months (95% C.I. 1.9, 6.2). Toxicities with an incidence of > 50% included nausea, elevated serum creatinine, edema, anemia, hypocalcemia, fatigue, diarrhea, vomiting, and dyspnea, and leukopenia. Conclusion: The combination of everolimus with imatinib in previously treated patients with advanced renal carcinoma did not result in a sufficient 3-month progression-free rate to warrant further investigation of this combination.