Prostate with grief

According to the Prostate Cancer Foundation (PCF), it is estimated that this year, 230,000 new cases of prostate cancer will be diagnosed in the United States. Unfortunately, that number is expected to increase to 300,000 by the year 2012. In addition, approximately 29,900 men will die from the disease this year.

Several medications to treat prostate cancer have recently been approved for use in this country, with several more in the final phases of development. Pharmacists can play a significant role by encouraging patients to see a physician, either for screening or to address any symptoms they may be experiencing.

Who's at risk? According to PCF, it is likely that a variety of causes and contributing factors lead to prostate cancer. Age, race, and family history are the major known risk factors, said Tony Palmer, R.Ph., M.B.A., clinical associate professor and director of Continuing Pharmaceutical Education at the University of Oklahoma College of Pharmacy in Tulsa.

Although Caucasians are the largest group of men that develop prostate cancer, PCF has found that, in raw numbers, more African-American men develop the disease than white men. In fact, African-American men are 65% more likely to develop the disease, and they develop more virulent forms of prostate cancer and are more than twice as likely to die from their disease compared with white men.

Approximately 25% of men with prostate cancer have a family history of the disease. It is believed, however, that only 9% of prostate cancers are purely hereditary, said PCF.

New treatment options Luteinizing hormone-releasing hormone (LHRH) agonists are a mainstay in treating locally advanced and metastatic prostate cancer. The market is dominated by four-month and shorter depot injections and implants, such as leuprolide acetate (Lupron, TAP Pharmaceuticals) for depot suspension and the goserelin (Zoladex, AstraZeneca) implant.

Sanofi-Aventis announced last month the U.S. availability of leuprolide (Eligard) 45 mg for injectable suspension, the first six-month injectable LHRH agonist approved for the palliative treatment of advanced prostate cancer. Eligard 45 mg is injected subcutaneously with a small-gauge needle. Once injected, it forms a solid bead that slowly releases the active ingredient over the course of six months.

The Food & Drug Administration also recently approved the long-acting LHRH agonist histrelin (Vantas, Valera Pharmaceuticals) implant for the palliative treatment of advanced prostate cancer. According to Valera, the Vantas implant uses its Hydron Implant technology to provide continuous subcutaneous release of histrelin at a rate of 50 to 60 mcg per day over a 12-month period.

The implant consists of a 50-mg histrelin drug core inside a nonbiodegradable, cylindrically shaped hydrogel reservoir, said Martin Dineen, M.D., a principal investigator at Atlantic Urological Associates in Daytona Beach, Fla. He said that Vantas is the first implant of its kind. The other 12-month LHRH product, leuprolide (Viadur, Bayer/Johnson & Johnson), is a titanium cylinder with an osmotic pump that pushes the fluid out through a diffusion moderator on one end of the cylinder, he explained.

The Vantas implant is quite soft, so it is barely palpable beneath the skin, Dineen said. Valera said that Vantas is implanted subcutaneously on the inner side of the upper arm and must be removed after 12 months of therapy. Vantas can be easily removed if the patient is intolerant of treatment, and the therapy stops immediately, he said. The therapeutic alternatives are injections that last one to six months, he said. If the patient has an adverse response to the shots, there is nothing the physician can do.

Last May, the FDA approved docetaxel Injection Concentrate (Taxotere, Sanofi-Aventis) for use with prednisone for the treatment of hormone-refractory metastatic prostate cancer. Docetaxel, a member of the taxoid class of chemotherapeutic agents, promotes the assembly of cellular microtubules and blocks their disassembly, thereby preventing mitosis and promoting cancer cell death.

Docetaxel was previously approved in the United States for the treatment of locally advanced or metastatic breast cancer after failure of prior chemotherapy, and for nonresectable locally advanced or metastatic non-small cell lung cancer in combination with cisplatin, either as a first-line treatment or after failure of platinum-based chemotherapy.