Tamsulosin, a selective alpha 1c-adrenoceptor antagonist: a randomized, controlled trial in patients with benign prostatic 'obstruction' (symptomatic BPH). The European Tamsulosin Study Group.

Objective: To evaluate the efficacy and safety of tamsulosin 0.4 mg once daily (as a modified-release formulation) compared with placebo in patients with benign prostatic enlargement, lower urinary tract symptoms and prostatic 'obstruction' (symptomatic benign prostatic hyperplasia [BPH]).

Patients And Methods: Of 313 patients with symptomatic BPH enrolled in a 2-week placebo run-in period, 296 were subsequently randomized to receive either placebo (98 patients) or tamsulosin 0.4 mg once daily (198 patients) for 12 weeks. The primary variables assessed to determine efficacy were maximum urinary flow rate (Qmax) from free-flow measurements and the total Boyarsky symptom score.

Results: Tamsulosin produced greater improvements in Qmax (1.4 mL/s, 13.1%) than did placebo (0.4 mL/s, 3.8%) (P = 0.028) and a greater decrease in total symptom score (3.4 points, 35.8% reduction) than did placebo (2.2 points, 23.7% reduction) (P = 0.002). Significantly more tamsulosin-treated patients (67%) than placebo-treated patients (44%) had a > or = 25% decrease in total symptom score after 12 weeks (P < 0.001). Treatment with tamsulosin for 12 weeks also produced significant improvements in average urinary flow rate (P = 0.040), irritative (P = 0.013) and obstructive (P = 0.014) symptom scores and symptoms of nocturia (P = 0.022) and hesitancy (P = 0.004). Tamsulosin was tolerated well by the patients. The incidence of adverse events emerging during treatment was comparable in the tamsulosin- and placebo-treated groups (34% and 24% respectively, P = 0.109), as was the incidence of cardiovascular-related adverse events (5% and 7% respectively; P = 0.596). There were no significant differences in changes in blood pressure or pulse rates between the tamsulosin- and placebo-treated groups.

Conclusion: Tamsulosin 0.4 mg once daily is safe, well tolerated and clinically effective in improving symptoms and urinary flow rate in patients with symptomatic BPH.