Study to Compare the Efficacy and Safety of Combination Treatment With Dutasteride and Tamsulosin With Tamsulosin Monotherapy, in Men With Moderate to Severe Benign Prostatic Hyperplasia

This is a multicentre, randomised, double-blind, parallel group study in Asian subjects. The aim of the study is to investigate whether combination therapy with dutasteride and tamsulosin is more effective than tamsulosin monotherapy for the improvement of symptoms and health outcomes in an at risk population of benign prostatic hyperplasia (BPH) clinical progression including older men (\>=50 years), with moderate-severe symptoms of BPH, enlarged prostates (\>=30 cubicentimeter \[cc\]) and prostate specific antigen (PSA) \>= 1.5 nanograms per milliliter (ng/mL). Each subject who met the eligibility criteria at screening will enter a four-week single-blind, placebo run-in period following which each subject will be randomised into a 2 year double-blind treatment phase. The total study duration for each subject will be up to 110 weeks.