GlaxoSmithKline (GSK) announced the US Food and Drug Administration (FDA) has approved Jalyn, a single-capsule combination of dutasteride (0.5 mg) and tamsulosin (0.4 mg) to treat symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate. BPH is one of the most common prostate disorders, affecting nearly half of all men 50 years of age or older in the US. In a clinical study of nearly 5,000 men, co-administration of these two medicines significantly improved symptoms of BPH compared to either medicine taken alone. GSK expects to make the product available during the second half of 2010.

"This is the first time these therapies will be available together in a once-daily capsule," said Anne Phillips, M.D., vice president, R&D medicine development leader, GSK. "Jalyn offers two mechanisms of action to provide symptom improvement and the ability shrink the prostate over a sustained time."

Common symptoms of BPH caused by an enlarged prostate include awakening at night to urinate, frequent urination, urgency, incomplete bladder emptying, starting and stopping, and weak stream. If left untreated, in severe cases, BPH can get worse over time and require catheterization or hospitalization for the inability to urinate, or prostate-related surgery.

Approval of the combination was based on two-year results from the CombAT (Combination of Avodart and Tamsulosin) study, one of the largest clinical trials to date of men with BPH (4,844 patients). The study compared changes in urinary symptoms seen with dutasteride co-administered with tamsulosin as opposed to either medicine alone. Changes were measured via a validated symptom index.

Reported adverse events were consistent with the known safety profiles of dutasteride and tamsulosin. The most common adverse reactions reported in subjects receiving combination therapy were impotence, decreased libido, breast disorders (including breast enlargement and tenderness), ejaculation disorders and dizziness.

Dutasteride, marketed by GSK as Avodart, currently is FDA-approved for the treatment of symptomatic BPH in men with an enlarged prostate, to reduce the risk of acute urinary retention (AUR), and to reduce the risk of prostate-related surgery. Avodart treats symptoms and over time can shrink the prostate. Tamsulosin, an alpha-blocker, is indicated for the treatment of the signs and symptoms of BPH. Tamsulosin works by relaxing the muscles in the bladder and prostate.

CombAT is an international multicenter, randomized, double-blind and parallel-group study. Men [aged ?50 years with a prostate volume (PV) ?30 cc, serum prostate-specific antigen (PSA) level 1.5-10 ng/mL, Qmax >5 and ?15 mL/sec with a minimum voided volume ?125 mL and International Prostate Symptom Score (IPSS) ?12] with moderate-to-severe BPH symptoms were randomized to receive dutasteride 0.5 mg/day plus tamsulosin 0.4 mg/day (n=1610), dutasteride 0.5 mg/day (n=1623), or tamsulosin 0.4 mg/day (n=1611).

Benign Prostatic Hyperplasia (BPH), also known as enlarged prostate, is a prevalent and progressive disease that affects 50 percent of men over 50 years of age and over 90 percent of men older than age 80. An enlarged prostate can lead to urinary symptoms because of its location around the urethra. Over time, the prostate can continue to grow and urinary symptoms may lead to urinary symptoms. Left untreated, in severe cases, an enlarged prostate can lead to serious long-term problems including acute urinary retention (AUR) and the need for prostate-related surgery, and in rare cases even kidney or bladder damage.