At the Feb. 2nd-4th, 2012 meeting of the American Society of Clinical Oncology (ASCO), positive results were presented for two different prostate cancer treatments both currently under late stage Phase III clinical development. The positive results led to the studies being stopped earlier than anticipated. These two drugs, radium-223 chloride (Alpharadin) and MDV3100 were both found to increase survival in metastatic, hormone-refractory prostate cancer patients and control the growth of bone metastases. Radium-223 chloride demonstrated improved survival and delayed cancer-related bone problems in men with advanced, spreading tumors. It delivers bursts of about four one thousandths of an inch of localized alpha radiation to the bone, thereby targeting the tumor. In addition, the average time to the first bone-break, fracture or need for radiation or surgery was significantly delayed among men treated with the new drug. The U.S. Food and Drug Administration (FDA) said it will fast track both Alpharadin and MDV3100 in its approval process for treatment in men with metastatic, hormone-resistant prostate cancer.
The second drug, MDV3100, increased survival by close to five months among men with advanced prostate cancer. This drug works by two routes. First it prevents testosterone from binding to receptors on cancer cells which require these male sex hormones in order to survive and grow. Secondly, MDV3100 prevents the production of proteins within the cell that induce tumor growth.
The next step for clinical researchers is to determine the best combination and sequence of administration of these two drugs in order to hopefully demonstrate their synergistic benefit which researchers believe is very plausible.
These positive reports were all recently independently published in: a) the ZeroHour Newsletter, Issue 26, Feb. 7th, 2012; b) the Feb. 7th, 2012 issue of the National Cancer Institute (NCI) Cancer Bulletin; and c) the February 9th on-line issue of the Prostate Cancer Research Institute (PCRI) Weekly (Volume 1, Issue 8). Additional highlights of the 2012 Genitourinary Cancers Symposium held at the Feb. ASCO meeting are also presented in the PCRI Weekly.
The same issue of the Feb. 7th NCI Cancer Bulletin also contained an analysis of the potential benefits and harms of three types of radiation therapy, a more recent proton therapy, brachytherapy and surgery for prostate cancer. Men considering any of these forms of therapy are urged to read this report and discuss it with their respective physicians.