In late summer 2005, the Willmar Cancer Center was designated by Bayer/Onyx as a research testing site for an investigational drug, sorafenib. Our application for investigator status was motivated by reports from other institutions suggesting an unusually high response rate for this drug, far better than the usual 10% rate seen with traditional toxic therapies. Sorafenib is a tyrosine-kinase inhibitor drug which targets the vascular endothelial growth factor receptor(VEGFR). Patients with metastatic renal cell cancer were eligible for study. Five patients have been enrolled at our institution. The drug is administered orally on a daily basis. The main toxicities have been rash and diarrhea, both manageable with dose modifications and supportive measures. So far, all five patients have shown reduction in the size and number of metastatic lesions. It is too early to say whether these responses will prove durable, but we are quite encouraged at present.

The study drug was provided at no cost to our patients up to the point of recent FDA approval for marketing under the trade name Nexavar. Patients were then converted to traditional insurance coverage for the drug. This can be a challenge owing to its cost of $5600 per month and a cumbersome prescribing procedure. Nonetheless, the drug's effectiveness has been quite impressive. A related agent, sunitinib (Sutent), has just been approved for renal cell cancer and gastrointenstinal stromal tumors (GIST). These are all part of a growing family of drugs including erlotinib (Tarceva) for lung and pancreatic cancer, and imatinib (Gleevec) for chronic myeloid leukemia and GIST.

William S. Shimp, M.D.
Department of Oncology