NEW YORK, N.Y – Three promising and innovative prostate cancer therapies are currently being investigated in clinical trials at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. The three trials – for patients with metastatic androgen-independent prostate cancer – include separate studies of two monoclonal antibody investigative therapies (177Lu-J591 and MLN2704, respectively) and a third study of an experimental drug, Atrasentan, in combination with chemotherapy.

Current treatment for advanced prostate cancer is limited and includes forms of androgen deprivation – the elimination of male testosterone. This therapy can cause side effects, and ultimately ceases to work as the cancer develops androgen-independent cells. Although chemotherapy has been demonstrated to improve survival, there is currently no curative treatment for prostate cancer once it has metastasized.

"Today, there is a tremendous need for new treatments for metastatic prostate cancer. Each of these three experimental therapies holds much promise," says Dr. Matthew I. Milowsky, the principal investigator on all three trials. Dr. Milowsky is assistant professor of medicine and urology at Weill Cornell Medical College and assistant attending physician at NewYork-Presbyterian/Weill Cornell.

Monoclonal antibodies can deliver anti-tumor therapies targeted directly to the tumor site, thereby minimizing exposure of radiation or chemotherapy to normal cells. The monoclonal antibody J591 is directed at the prostate-specific membrane antigen (PSMA). Unlike the protein PSA, which circulates in the blood, PSMA is a protein expressed on the cell surface of virtually all prostate cancer cells, and its abundance on the cell surface increases as the disease progresses and becomes refractory to hormonal therapy. PSMA has little to no expression in normal tissues.

The investigative therapy 177Lu-J591 comprises the monoclonal antibody J591 and the radioactive isotope 177Lu (Lutetium-177). A previous Phase I trial of 177Lu-J591, which was developed at Weill Cornell Medical College, demonstrated acceptable toxicity and evidence of anti-tumor activity. Approximately 32 patients will participate in the Phase II 177Lu-J591 trial, which seeks to evaluate disease response and to identify any side effects. Additional study sites include NewYork-Presbyterian Hospital/Columbia University Medical Center (principal investigator Dr. Daniel Petrylak, director of the genitourinary oncology program at New York-Presbyterian Hospital/Columbia and associate professor of medicine at Columbia University College of Physicians and Surgeons) and Memorial Sloan-Kettering Cancer Center (principal investigator Dr. Michael J. Morris).

The investigative therapy MLN2704 combines the same monoclonal antibody J591 and the chemotherapeutic maytansinoid drug DM1. This two-part Phase I/II dose-escalation trial for men with metastatic androgen-independent prostate cancer is designed to determine (1) the therapy's dose-limiting toxicity (DLT) and maximum tolerated dose (MTD), followed by (2) the therapy's response rate. The trial is also open at Memorial Sloan-Kettering Cancer Center (principal investigator Dr. Howard Scher).

The investigative therapy Atrasentan (ABT-627) in combination with Docetaxel and Prednisone incorporates prostate cancer chemotherapy -- docetaxel and prednisone -- with the investigational, novel anti-cancer drug, Atrasentan. Atrasentan is being evaluated in clinical trials to determine its ability to delay spread of the cancer by blocking endothelin-1 (ET-1), a protein that can induce the growth of prostate cancer cells. Atrasentan has been shown to slow the rate of cancer progression in clinical trials in metastatic (hormone refractory or androgen independent) prostate cancer. The primary objective of this Phase I study of approximately 30 patients is to determine the safety and tolerability of Atrasentan in combination with docetaxel and prednisone in men with metastatic, androgen-independent prostate cancer. In addition to NewYork-Presbyterian/Weill Cornell, the Atrasentan study is in the process of opening at NewYork-Presbyterian/Columbia, under the direction of Dr. Daniel Petrylak. Atrasentan was recently submitted as a new drug application to the U.S. Food and Drug Administration (FDA) for the treatment of metastatic hormone-refractory prostate cancer.

The monoclonal antibody J591 was developed in the laboratory of Dr. Neil Bander at Weill Cornell Medical College. In April 2001, Millennium Pharmaceuticals Inc. licensed this technology for the development and commercialization of antibody-based therapeutics targeting PSMA, including MLN2704. Millennium Pharmaceuticals Inc., of Cambridge, Mass., is sponsoring the current MLN2704 study. Abbott Laboratories of Chicago is sponsoring the current Atrasentan study.

Patients may inquire about these clinical trials by calling (212) 746-5430 or (212) 746-2920.

About Prostate Cancer Prostate cancer is the second most common cause of cancer death in men. According to the National Cancer Institute, there are approximately 1.7 million men living in the U.S. with a diagnosis of prostate cancer. In addition to this number, approximately 200,000 new cases of prostate cancer will be diagnosed, and 29,900 men will die of the disease this year in the United States. The five-year survival rate of men with prostate cancer is 89 percent, with this percentage jumping to 100 percent if the cancer is found before it metastasizes. Early detection is important, and the American Cancer Society recommends that men over the age of 50 have a PSA blood test every year. Coupled with a digital rectal exam (DRE), the PSA is a very useful test for determining which men need further evaluation. Men in high-risk groups should begin testing earlier (African-American men as well as those with a family history of prostate cancer are at high risk.)

About NewYork-Presbyterian Hospital/Weill Cornell Medical Center The NewYork-Presbyterian Hospital/Weill Cornell Medical Center, located in New York City, is one of the leading academic medical centers in the world, comprising the teaching Hospital NewYork-Presbyterian and its academic partner Weill Cornell Medical College. NewYork-Presbyterian/Weill Cornell provides state-of-the-art inpatient, ambulatory, and preventive care in all areas of medicine, and is committed to excellence in patient care, research, education, and community service. Along with Weill Cornell, Columbia University College of Physicians and Surgeons is NewYork-Presbyterian's major academic.