Watson Pharmaceuticals, Inc, a leading specialty pharmaceutical company, announced that the US Food and Drug Administration (FDA) has approved Rapaflo (silodosin), the company's new alpha blocker for the treatment of the signs and symptoms of BPH.

BPH is the number one reason patients visit urologists and is characterized by urination problems, including decreased urine flow, more frequent urination and nocturia. The US BPH market is growing and currently exceeds $2 billion annually, of which $1.7 billion is attributed to alpha blockers.

"Rapaflo's approval is the most important milestone for the company's Brand division thus far," said Paul Bisaro, chief executive officer of Watson. "Rapaflo is a novel product that provides strong efficacy and an exceptional safety profile for patients managing their BPH. Rapaflo provides an excellent long term opportunity for Watson and will be the foundation for future growth of our urology franchise."

This approval is based on data from two phase-3, 12-week, randomized, double-blind, placebo-controlled, multi-center studies as well as a 40 week open label study. In the two phase-3 studies, 923 patients (mean age 64.6 years) were randomized to receive either Rapaflo 8 mg once-daily or placebo. In the two trials, 8 mg once-daily Rapaflo for 12 weeks resulted in significant and rapid relief of BPH symptoms, compared with placebo, as measured by the International Prostate Symptom Score (IPSS). IPSS includes irritative (frequency, urgency, and nocturia), and obstructive (hesitancy, incomplete emptying, intermittency, and weak stream) symptoms. Rapaflo also has been proven to significantly improve Qmax scores (maximum urine flow rates) as early as two hours following first dose and at 12 weeks of treatment.

"We are pleased we received approval for Rapaflo so quickly which demonstrates, among other things, the high quality of our clinical and regulatory groups," said Bisaro. "With our oxybutynin gel NDA under consideration with the FDA and plans to file our Trelstar six month application later this year, Watson is in a unique position to introduce products within the next 12 to 18 months that treat the top three conditions in urology."

Rapaflo is an effective, selective alpha-1 adrenergic receptor antagonist. Rapaflo binds with high affinity to the alpha (1A) receptors concentrated in the prostate, causing the smooth muscles in these tissues to relax and resulting in improved urine flow and a reduction in BPH symptoms. The binding affinity for the alpha (1B) receptors that cause smooth muscle relaxation and blood pressure effects is significantly lower, thereby maximizing target organ activity for treating BPH and minimizing the potential for side effects and interactions with other therapies.

Watson Pharmaceuticals, Inc, headquartered in Corona, CA, is a leading specialty pharmaceutical company that develops, manufactures, markets, sells and distributes generic and specialty brand pharmaceutical products.