GlaxoSmithKline (GSK) has begun a new international clinical trial for men with enlarged prostate, known as benign prostatic hyperplasia (BPH).

The trial is evaluating dutasteride, a dual 5 alpha-reductase inhibitor (5 A-RI), in combination with the most widely prescribed alpha-blocker, tamsulosin. The combined drug is called Avodart.

GSK says the study will investigate the efficacy and safety of treatment with Avodart, administered once daily for four years, alone and in combination, on improving urinary symptoms and reducing the risk of disease progression in men with symptomatic BPH.

Twenty-five percent of the 4,500 patients will be enrolled in the United States, beginning in the in January 2004. The rest are being enrolled in Europe, beginning last month.