Comparative Efficacy of Sunitinib versus Sorafenib as First-Line Treatment for Patients with Metastatic Renal Cell Carcinoma

<b><i>Background:</i></b> This study investigated the efficacy and toxicity of sorafenib and sunitinib as primary treatment for patients with metastatic renal cell carcinoma (mRCC). <b><i>Methods:</i></b> We identified 49 and 220 patients treated with sorafenib and sunitinib, respectively, as first-line therapy in the Asan Medical Centre from April 2005 to March 2011. <b><i>Results:</i></b> Disease control rates of 71 and 74% were achieved with sorafenib and sunitinib, respectively (p = 0.687). After a median follow-up of 27.6 months, progression-free survival (PFS) and overall survival (OS) were not significantly different between the sorafenib and the sunitinib group (PFS 8.6 vs. 9.9 months, respectively, p = 0.948, and OS 25.7 vs. 22.6 months, p = 0.774). Patients treated with sorafenib required dose reduction due to toxicities less frequently than those treated with sunitinib (37 vs. 54%, p = 0.034). Haematological toxicity of grade 3 or 4 was more common in the sunitinib group than in the sorafenib group (45 vs. 4%, p < 0.001). Multivariate analysis showed old age, Heng's risk group, and bone and liver metastases, but not the type of vascular endothelial growth factor tyrosine kinase inhibitor, were independent prognostic factors affecting OS. <b><i>Conclusion:</i></b> The results of this study indicate that sorafenib has comparable efficacy to sunitinib in the treatment of mRCC patients and fewer and less severe toxicities, but the number of patients included in the study was small.