Novel chemo drug helps treat prostate cancer

Men with a certain type of prostate cancer have been shown to respond to a new chemotherapy drug, Sagopilone, plus prednisone in an international trial led by Oregon Health & Science University Cancer Institute researchers.

The research involved men with androgen-independent prostate cancer that has metastasized, meaning their cancer has spread beyond the prostate and is not longer responding to hormonal therapies. This is the most advanced form of prostate cancer. Prostate cancer is the most common type of cancer in men in the United States, where it is responsible for more male deaths than any other cancer, except lung cancer.

"We are showing solid activity that this drug shows promise," said Tomasz Beer, M.D., principal investigator. He is the Grover C. Bagby Endowed Chair for Cancer Research, director of the Prostate Cancer Research Program at the OHSU Cancer Institute and associate professor of medicine (hematology/medical oncology), OHSU School of Medicine.

This research will be presented Saturday, May 31 at 8 a.m. at the annual American Association of Clinical Oncology in Chicago.

Of the 37 study participants taking the Sagopilone and prednisone long enough to be evaluated, the majority showed positive results in the reduction of their prostate specific antigens, or PSA. PSA is often elevated in the presence of prostate cancer.

During the three-month trial thirteen study participants had a more than 50 percent reduction in their PSA; 23 showed a 30 percent reduction; one who had radiographic measurable disease showed complete response; and four had unconfirmed prostate response. A 30 percent reduction in PSA levels in three months is a strong indicator of survival.

Sagopilone, a fully synthetic derivation, is a new class of drug that inhibits growth and the spread of malignant cell, similar to docetaxel, which has been the gold standard for this type of hormone independent prostate cancer. Docetaxel, however, it is not a cure and not all patients benefit from it. For this reason, Beer and colleagues are committed to searching for new drugs that will be effective against advanced prostate cancer.

"We look forward to completing this study and to the further investigation of Sagopilone as a new treatment option for men with advanced prostate cancer," said Beer.