Multi-targeted anticancer drug shows promise as treatment for metastatic renal cell cancer

A new multi-targeted anticancer drug called SU11248 has shown very promising results in the treatment for metastatic renal cell cancer, one of the most chemotherapy resistant of all cancers. The study's lead investigator, Robert Motzer, MD, attending physician at Memorial Sloan-Kettering Cancer Center (MSKCC) reported the results of a Phase II study today at the American Society for Clinical Oncology annual meeting.

"This early study of SU11248 in the treatment for renal cancer has shown more activity as a single agent then any other drug I've studied in the past 15 years," said Dr. Motzer. "While further research needs to be done to confirm these findings, I am very encouraged by this type of significant activity so early on, in treating such an aggressive disease," he added.

The novel agent, SU11248 works through simultaneously blocking multiple tumor growth factor receptors known as tyrosine kinases. These receptors are thought to be responsible for cancer growth and metastases. Through targeting multiple receptors --vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and others -- SU11248 cuts off the blood supply of the cancer while at the same time destroying cellular reproduction.

Renal cell cancer is diagnosed in approximately 30,000 people per year and has a five-year survival rate of about 55 percent. The current standard treatment for metastatic renal cell cancer is interleukin-2 and interferon-alpha, but only 15 percent of treated patients have a response.

In the current study, 63 patients with metastatic (advanced) renal carcinoma whose cancer had failed to respond to standard therapy received SU11248. Twenty-one of them (33 percent) showed a partial response to the drug, another 40 percent had disease stabilization. Six months later, the SU11248 response has persisted in some patients, and 14 of the responders continue on treatment with an ongoing partial response. The drug is taken orally and it was generally well tolerated, with patients experiencing mild to moderate side effects.

This was a multi-center study that included investigators from several US centers. The study is sponsored by Pfizer Pharmaceuticals.

Dr. Motzer is also the lead investigator on a pivotal Phase III trial for SU11248 as the second line of therapy. Additionally, there will be another Phase III trial comparing SU11248 to the standard therapy of interferon. This trial is expected to start accrual in the next few months.