The U.S. Food and Drug Administration (FDA) has approved a supplemental new drug application for Avodart (dutasteride) for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to improve urinary symptoms, reduce risk of acute urinary retention (AUR) and reduce the risk of the need for BPH-related surgery.
Avodart, a second-generation 5 alpha-reductase inhibitor, is the first and only medicine to inhibit both the type 1 and type 2 enzymes responsible for the conversion of testosterone to DHT (dihydrotestosterone), the primary cause of prostate growth. Avodart's dual inhibition decreases levels of DHT by 90 per cent at two weeks and 93 per cent at two years.
By reducing DHT levels, Avodart reduces the size of an enlarged prostate. In clinical studies, this reduction in prostate volume was seen as early as one month with reductions continuing through treatment. Shrinking the enlarged prostate relieves urinary obstruction and improves urinary flow. Avodart also improves urinary symptoms and reduces the risk of AUR (the sudden complete inability to urinate) and BPH-related surgery, two potential long-term serious consequences of BPH. The pivotal phase III study data were published in this month's edition of the journal Urology.
BPH is one of the most common health problems in older men. BPH often begins after age 50 and can progress and worsen as men age. More than half of men over age 60 experience BPH, and by age 80, nearly 80 percent of men have the disease. In the United States alone, 375,000 hospital stays each year involve a diagnosis of BPH.
BPH is a progressive disease in which the prostate gland surrounding the urethra enlarges. As it grows, the prostate obstructs the urethra, the tube through which urine flows, causing urinary difficulties. BPH symptoms may interfere with normal activities and reduce the sense of well being. Symptoms of BPH vary, but the most common involve urinary problems, such as a hesitant, interrupted weak stream; urgency and leaking or dribbling; and more frequent urination, especially at night. In severe cases, the bladder and the kidney may become damaged.
To diagnose BPH, a physician will discuss urinary symptoms with a patient and conduct a digital rectal exam. A physician may also use a simple blood test that measures a protein called "prostate-specific antigen," or PSA. PSA is produced by the prostate, and an increase in levels is associated with prostate growth. While PSA is primarily used as a screening tool for prostate cancer, it can also be used to determine prostate enlargement.
Avodart, to be available for prescription in December 2002, was developed by GlaxoSmithKline, with U.S. operations in Philadelphia and Research Triangle Park, N.C., one of the world's leading research-based pharmaceutical and health care companies. GlaxoSmithKline is committed to improving the quality of human life by enabling people to do more, feel better and live longer.