Objective: This open-label extension study evaluated the efficacy and safety of tamsulosin (0.4 mg as a modified release formulation) once daily in patients with lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction (BPO) treated for up to 3 years. Methods: Patients were enrolled from two European, 12-week, placebo-controlled trials. This analysis reports on 355 patients randomized originally to tamsulosin (n = 244) or placebo (n = 111) in the two placebo-controlled trials with follow-up data for up to 3 years. Results: The significant improvements in the primary efficacy parameters, maximum urinary flow rate (Qmax) and total Boyarsky symptom score that were observed during the placebo-controlled trials were sustained throughout the long-term extension study for up to 3 years in patients who remained on therapy. Mean Qmax increased from baseline (range 0.7–1.8 ml/s; p < 0.05 vs. baseline) and remained between 11.5 and 12 ml/s during the entire follow-up period. Total Boyarsky symptom score also improved from baseline (range –3.7 to –4.1 (or –39 to –44%); p < 0.001 vs. baseline). Similarly, the percentage of treatment responders, defined as an increase in Qmax of ≥30% or a decrease in total symptom score of ≥25%, remained constant throughout the 3-year period. The number of patients who had a clinically significant total Boyarsky symptom score response ranged between 69 and 80%. During the 3-year study period, 95 patients (27%) experienced an adverse event considered to be possibly or probably related to study medication, the most common of which (occurring in ≤6% of patients) were dizziness and abnormal ejaculation. There were no clinically significant changes in blood pressure or pulse rate during the study. Conclusion: Long-term tamsulosin therapy is safe, well-tolerated and improvements in urinary flow and symptoms are maintained in patients with LUTS suggestive of BPO who remain on treatment for up to 3 years.

Keywords:
Lower urinary tract symptoms, Benign prostatic obstruction, α1A-Adrenoceptor antagonist, Tamsulosin, 3-year follow-up
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1999
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