Efficacy and safety of tamsulosin 0.4 mg single pills for treatment of Asian patients with symptomatic benign prostatic hyperplasia with lower urinary tract symptoms: a randomized, double-blind, phase 3 trial

Objective: To verify the efficacy and safety of tamsulosin 0.4 mg and tamsulosin 0.2 mg compared with those of placebo in patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). Methods: A total of 494 patients from multiple centers participated in this double-blind, randomized, phase 3 trial. Eligible patients were randomly assigned to the tamsulosin 0.4 mg group, tamsulosin 0.2 mg group or placebo group. The International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), post-void residual (PVR) urine volume, blood pressure, heart rate and adverse events were compared among the three groups at 4, 8 and 12 weeks. Results: A total of 494 BPH patients were analyzed. There were no differences in the baseline characteristics among the three groups. After 12 weeks of treatment, total IPSS was improved in the 0.2 mg and 0.4 mg tamsulosin groups; however, the extent of improvement was greater in the 0.4 mg group than in the 0.2 mg group (0.4 mg: -9.59 vs. 0.2 mg: -5.61; least-squares mean difference [95% confidence interval]: -3.95 [-5.01, -2.89], p < .0001). In addition, in the patients with severe symptoms (IPSS >= 20), total IPSS was improved the most in the 0.4 mg group (-11.27 +/- 5.00, p < .0001). Qmax and PVR were improved in the 0.4 mg and 0.2 mg groups; however, the differences were not statistically significant between treatment groups. No patients experienced any serious adverse effects in any of the three groups. Conclusions: Tamsulosin 0.4 mg and 0.2 mg appear to be superior to placebo treatment, and tamsulosin 0.4 mg is more effective than 0.2 mg in terms of total IPSS improvement. Tamsulosin 0.4 mg has favorable efficacy and tolerability in Asian men with symptomatic BPH.