Non‐inferiority of silodosin to tamsulosin in treating patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH)

Abstract

What's known on the subject? and What does the study add?Silodosin administered by 4 mg twice daily is as effective as tamsulosin 0.2 mg daily in treating patients with LUTS associated with BPH.Relative to tamsulosin, silodosin has less cardiovascular side effects as judged by the minimal changes of blood pressure and pulse rats after treatment. OBJECTIVE• To test the hypothesis that the efficacy of silodosin would not be inferior to tamsulosin in treating patients with lower urinary tract symptoms associated with benign prostate hyperplasia (BPH). PATIENTS AND METHODS• At nine medical centres, 209 patients with an International Prostate Symptom Score (IPSS) of ≥ 13 were randomized to silodosin (4 mg twice daily) or tamsulosin (0.2 mg once daily) for 12 weeks.• The primary efficacy measure was the mean change from baseline to endpoint in IPSS.• The non-inferiority margin of the IPSS change was set at 1.0.• Secondary efficacy measures included change in maximal urinary flow rate (Q max ) and health-related quality of life (HRQL) score. RESULTS• Of the 170 (81.3%) patients who completed the study, 86.2% in the silodosin group vs 81.9% in the tamsulosin group achieved a ≥ 25% decrease in IPSS ( P = 0.53).• The mean difference (silodosin minus tamsulosin) in IPSS change from baseline was − 0.60 (95% confidence interval − 2.15, 0.95), inferring the non-inferiority of silodosin to tamsulosin.• The mean changes in the Q max and HRQL score from baseline were comparable between the groups (both, P > 0.05). Although patients receiving silodosin had a significantly higher incidence of abnormal ejaculation (9.7% vs tamsulosin 1.0%, P = 0.009), only 1.9% discontinued treatment.• Tamsulosin treatment resulted in a significant reduction in mean systolic blood pressure ( − 4.2 mmHg, within-group P = 0.004) relative to the negligible change of silodosin ( − 0.1 mmHg, within-group P = 0.96) CONCLUSION• The trial shows the non-inferiority of silodosin 4 mg twice daily to tamsulosin 0.2 mg once daily in patients with symptoms of BPH.

Silodosin is effective for treatment of LUTS in men with BPH: a systematic review

“…All studies [14][15][16]18 were randomized, double-blind, multicentre studies. The study durations were each 12 weeks.…”

“…Three [14][15][16] of the four studies were placebo-controlled studies. Three 14,16,18 of the four studies compared 8 mg silodosin with 0.2 mg tamsulosin. However, in one study, 16 the standard deviation could not be estimated by the statistical method.…”

“…All studies used 8 mg silodosin for LUTS in men with BPH. One RCT 16 was conducted in Europe, one RCT 15 was conducted in the USA and the two remaining RCTs 14,18 were conducted in Asia. The characteristics and quality assessment of the four studies are summarized in Tables 1 and 2.…”

“…for the mean change from baseline in the IPSS, peak urine flow and QoL score were 21.14 points, 20.85 ml s 21 and 20.26 points, respectively. In these studies, 14,15,18 the most commonly reported adverse reaction for silodosin was ejaculation disorder. Compared with 0.2 mg tamsulosin, the incidence of ejaculation disorder was higher (18% vs. 4%) in this meta-analysis.…”

A Prospective Study Comparing Tamsulosin and Silodosin in Medical Expulsive Therapy for Lower Ureteric Stones

“…(24) The incidence of orthostatic hypotension with silodosin has been reported to be <3%. (25) Results from our study shows retrograde ejaculation in 5 (19.2%) patients treated with silodosin and none in tamsulosin group.…”