First-line phase II trial of sorafenib (BAY 43–9006) in patients with advanced renal cell carcinoma unsuitable for cytokine treatment

15640 Background: Sorafenib (BAY 43–9006) is a serine/threonine and receptor tyrosine kinase inhibitor that prevents tumor cell proliferation and angiogenesis. The objective of this open-label, phase II trial was to determine median progression-free survival (PFS) following sorafenib therapy in patients with renal cell carcinoma (RCC) unsuitable for cytokine treatment. Methods: Eligible patients had cytologically or histologically confirmed clear cell RCC; Eastern Cooperative Oncology Group (ECOG) Performance Status 0–1; adequate renal, liver and medullar function; no active central nervous system metastases; had received no previous treatment with antiangiogenic agents; and had at least one evaluable lesion. Sorafenib was given as first-line treatment in patients unsuitable for cytokine therapy, defined as being intolerant to or ineligible for immunotherapy. Treatment consisted of oral sorafenib 400mg twice daily continuously until disease progression or unacceptable toxicity. The primary endpoint was PFS; secondary endpoints were response rate according to Response Evaluation Criteria in Solid Tumors, tolerability and overall survival. Results: Twenty-six patients were enrolled between March and July 2006 (median age: 68.5 years [48–82]; male/female: 17/9, ECOG Performance Status 0: 11 patients; prior nephrectomy: 19 patients). The main metastatic locations were lung and bone, 14 patients had = 2 metastatic lesions, and 2 patients had abnormal lactate dehydrogenase levels. As of 31 December 2006, with a median follow-up of 6.4 months, the median PFS had not been reached. In 19 patients evaluable for response, the overall clinical benefit rate was 68.4% (1 complete response; 1 partial response; 11 stable disease). Six patients experienced serious adverse events, only one of which was related to treatment. Conclusions: Sorafenib first-line therapy is a tolerable alternative for patients unsuitable for cytokine treatment. Final PFS data will be available in June 2007. No significant financial relationships to disclose.