
Two Phase III clinical trials of Watson Pharmaceuticals, Inc. (NYSE: WPI)’s Silodosin yielded top-line positive results.
Kissei Pharmaceutical Co., Ltd. originally developed Silodosin in Japan and licensed to Watson for the US, Canada and Mexico markets.
Silodosin, a novel, highly uroselective alpha (1A)-adrenoceptor antagonist, preferentially binds to the alpha (1A) receptors in the prostate and bladder neck relative to cardiovascular associated receptors, thereby maximizing target organ activity while minimizing the potential for blood pressure effects.
The said studies investigated whether 8mg silodosin given once daily for 12 weeks was superior to placebo for the relief of BPH symptoms (both obstructive and irritative symptoms) and if maximum urine flow was improved.
Both studies showed the Silodosin was well tolerated. Affecting more than half of men in their sixties and as many as 90% of men by the age of 85 in the United States, BPH is characterized by a non-cancerous enlarged prostate that leads to obstructive and irritative urinary symptoms.
Launched May 2006 in Japan, Urief® (silodosin) 4mg (dosed twice daily) is marketed in cooperation with Daiichi Pharmaceutical Co., Ltd.
Source: Watson Pharmaceuticals, Inc.






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