According to an early online publication in the Journal of Clinical Oncology, the agent Nexavar® (sorafenib) provides significant anticancer activity in patients with metastatic renal cell carcinoma.
The kidneys are each filled with tiny tubules that clean and filter the blood-the process that removes waste and makes urine. Renal cell cancer (RCC) is a malignancy involving these tubules of the kidney. Metastatic RCC refers to cancer that has spread from the kidney to distant sites in the body.
Treatment for RCC can be extensive and may produce poor outcomes. The four basic treatment options for renal cell carcinoma include: surgery, radiation, chemotherapy, and biologic therapy (biologic therapy uses substances made by the body or made in a laboratory that boost or direct the patient’s own immune system to fight the cancer). Stem cell transplantation is also being evaluated for RCC. Nexavar is a new approach that targets enzymes involved in both tumor growth and tumor blood supply.
Nexavar was approved based on the results of a large phase III clinical trial of patients with advanced RCC. Compared to patients treated with placebo (inactive substitute), patients treated with Nexavar survived for roughly twice as long without cancer progression: median survival without evidence of cancer growth was six months among patients treated with Nexavar and three months among patients treated with placebo. At the time of these interim analyses, there was no significant difference in overall survival, but patients will continue to be followed.
Results from a phase II clinical trial have recently been published. This multicenter trial included 202 patients with metastatic RCC who were initially treated with Nexavar for at least 12 weeks. Patients whose cancer shrunk less than 25% were either treated with further Nexavar or placebo; patients whose cancer shrunk more than 25% continued treatment with Nexavar, and those whose cancer progressed and grew at least 25% continued treatment with Nexavar.
- 73 patients achieved cancer shrinkage of at least 25% following the first 12 weeks on Nexavar; these patients received further treatment with Nexavar.
- 65 patients achieved disease stabilization (up to a reduction of 25% of cancer size). They were then treated with further Nexavar or with placebo.
- Of the group of patients who had achieved disease stabilization and received further treatment with Nexavar, 50% remained progression-free at six months compared with only 18% of those who went on to receive placebo.
- Of the patients who achieved disease stabilization upon initial treatment with Nexavar, median progression-free survival from the time patients were treated with subsequent Nexavar was six months compared to only six weeks for those who received placebo.
- Common side effects were rash, fatigue, and skin reactions on the palms of the hands or soles of the feet.
- There were no deaths attributed to therapy with Nexavar.
The researchers concluded that these results give further confirmation that Nexavar provides significant improvements in outcomes among patients with metastatic RCC.
Patients with metastatic RCC should speak with their physician regarding their individual risks and benefits of treatment with Nexavar.
Reference: Ratain MJ, Eisen T, Stadler WM, et al. Phase II placebo-controlled randomized discontinuation trial of sorafenib in patients with metastatic renal cell carcinoma. Published ahead of print on April 24, 2006 as 10.1200/JCO.2005.03.6723.