Authors reply: an adjusted indirect comparison of everolimus and sorafenib therapy in sunitinib-refractory metastatic renal cell carcinoma patients using repeated matched samples.

University Federico II of Napoli, Department of Medical Oncology, Endocrinology and Oncology , Naples , Italy.
Expert Opinion on Pharmacotherapy (Impact Factor: 2.86). 03/2012; DOI: 10.1517/14656566.2012.668097
Source: PubMed
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    ABSTRACT: Everolimus (RAD001) is an orally administered inhibitor of the mammalian target of rapamycin (mTOR), a therapeutic target for metastatic renal cell carcinoma. We did a phase III, randomised, double-blind, placebo-controlled trial of everolimus in patients with metastatic renal cell carcinoma whose disease had progressed on vascular endothelial growth factor-targeted therapy. Patients with metastatic renal cell carcinoma which had progressed on sunitinib, sorafenib, or both, were randomly assigned in a two to one ratio to receive everolimus 10 mg once daily (n=272) or placebo (n=138), in conjunction with best supportive care. Randomisation was done centrally via an interactive voice response system using a validated computer system, and was stratified by Memorial Sloan-Kettering Cancer Center prognostic score and previous anticancer therapy, with a permuted block size of six. The primary endpoint was progression-free survival, assessed via a blinded, independent central review. The study was designed to be terminated after 290 events of progression. Analysis was by intention to treat. This study is registered with, number NCT00410124. All randomised patients were included in efficacy analyses. The results of the second interim analysis indicated a significant difference in efficacy between arms and the trial was thus halted early after 191 progression events had been observed (101 [37%] events in the everolimus group, 90 [65%] in the placebo group; hazard ratio 0.30, 95% CI 0.22-0.40, p<0.0001; median progression-free survival 4.0 [95% CI 3.7-5.5] vs 1.9 [1.8-1.9] months). Stomatitis (107 [40%] patients in the everolimus group vs 11 [8%] in the placebo group), rash (66 [25%] vs six [4%]), and fatigue (53 [20%] vs 22 [16%]) were the most commonly reported adverse events, but were mostly mild or moderate in severity. Pneumonitis (any grade) was detected in 22 (8%) patients in the everolimus group, of whom eight had pneumonitis of grade 3 severity. Treatment with everolimus prolongs progression-free survival relative to placebo in patients with metastatic renal cell carcinoma that had progressed on other targeted therapies.
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    ABSTRACT: No previous prospective trials have been reported with sorafenib in patients with sunitinib-refractory metastatic renal cell cancer (MRCC). We conducted a multicenter study to determine the activity and tolerability of sorafenib as second-line therapy after sunitinib progression in MRCC. Between January 2006 and September 2008, 52 patients were enrolled onto this single-arm phase II study. All patients received sorafenib 400 mg orally twice a day until disease progression or intolerable toxicity. The primary end point was objective response rate (complete or partial response) evaluated every 8 weeks by use of the Response Evaluation Criteria in Solid Tumors; secondary end points were toxicity, time to progression (TTP), and overall survival (OS). All patients were included in response and safety analyses. Partial responses were observed in 9.6% of patients (five of 52 patients; 95% CI, 5% to 17%) after two cycles. Grade 1 to 2 fatigue, diarrhea, nausea/vomiting, rash, and neutropenia were the most common side effects, noted in 16 (30.8%), 19 (36.5%), 20 (38.5%), 19 (36.5%), and 20 patients (38.5%), respectively. The most common grade 3 toxicity was diarrhea, noted in six patients (11.5%). Median TTP was 16 weeks (range, 8 to 40 weeks), and median OS was 32 weeks (range, 16 to 64 weeks). Although well tolerated, sorafenib shows limited efficacy in sunitinib-refractory MRCC. Further randomized trials comparing sorafenib with other drugs that target different biologic pathways are needed to define the best second-line treatment option in these patients.
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