Rapid Efficacy of the Highly Selective α 1A -Adrenoceptor Antagonist Silodosin in Men With Signs and Symptoms of Benign Prostatic Hyperplasia: Pooled Results of 2 Phase 3 Studies

No AccessJournal of UrologyAdult Urology1 Jun 2009Rapid Efficacy of the Highly Selective α1A-Adrenoceptor Antagonist Silodosin in Men With Signs and Symptoms of Benign Prostatic Hyperplasia: Pooled Results of 2 Phase 3 Studiesis accompanied byThe Role of α1-Adrenoceptor and Arachidonate Pathways in Increased Tone of Demucosalized Bladder Tissueis companion ofRapid Efficacy of the Highly Selective α1A-Adrenoceptor Antagonist Silodosin in Men With Signs and Symptoms of Benign Prostatic Hyperplasia: Pooled Results of 2 Phase 3 Studies Leonard S. Marks, Marc C. Gittelman, Lawrence A. Hill, Weining Volinn, and Gary Hoel Leonard S. MarksLeonard S. Marks University of California at Los Angeles and Urological Sciences Research Foundation, Los Angeles, California , Marc C. GittelmanMarc C. Gittelman South Florida Medical Research, Aventura, Florida , Lawrence A. HillLawrence A. Hill Watson Laboratories, Salt Lake City, Utah , Weining VolinnWeining Volinn Watson Laboratories, Salt Lake City, Utah , and Gary HoelGary Hoel Watson Laboratories, Salt Lake City, Utah View All Author Informationhttps://doi.org/10.1016/j.juro.2009.02.034AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: We evaluated the efficacy and safety of silodosin for treatment of benign prostatic hyperplasia symptoms in 2 randomized, placebo controlled, phase 3 studies. Materials and Methods: Men 50 years or older with an International Prostate Symptom Score of 13 or greater and peak urinary flow rate of 4 to 15 ml per second received placebo or 8 mg silodosin daily with breakfast for 12 weeks. The primary end point was International Prostate Symptom Score change from baseline to last observation. Change in peak urinary flow rate was a secondary end point. Differences in treatment efficacy were assessed by ANCOVA. Results: Of 923 patients (mean age 65 years) 466 received silodosin and 457 placebo. After 0.5 week (range 3 to 4 days) of treatment patients receiving silodosin vs placebo achieved significant improvement in total International Prostate Symptom Score (difference −1.9, p <0.0001) and irritative (–0.5, p = 0.0002) and obstructive (–1.4, p <0.0001) subscores. The mean ± SD change from baseline in total International Prostate Symptom Score was −4.2 ± 5.3 for silodosin vs −2.3 ± 4.4 for placebo. Differences (silodosin vs placebo) in International Prostate Symptom Score and subscores increased by week 12 (p <0.0001). Mean change from baseline in peak urinary flow rate (ml per second) 2 to 6 hours after initial dose was greater (p <0.0001) with silodosin (2.8 ± 3.4) than placebo (1.5 ± 3.8). Differences remained significant (p <0.001) through week 12. The most common treatment emergent adverse event was (mostly mild) retrograde ejaculation (silodosin 28.1% of patients, placebo 0.9%). Few patients receiving silodosin (2.8%) discontinued because of retrograde ejaculation. Proportions of patients with treatment emergent orthostatic hypotension were similar for silodosin (2.6%) and placebo (1.5%). Conclusions: Treatment with silodosin produced rapid improvement in urinary symptoms that was sustained for 12 weeks. Silodosin was well tolerated with a low incidence of orthostatic hypotension. References 1 : Benign prostatic hyperplasia. In: Urologic Diseases in America. Edited by . Bethesda, MD: National Kidney and Urologic Diseases Information Clearinghouse2007. NIH publication 07-5512: 43-67. Available at: http://kidney.niddk.nih.gov/statistics/uda/ (updated February 2007). Accessed August 28, 2008. Google Scholar 2 : Pathophysiology of lower urinary tract symptoms in the aging male population. Rev Urol2005; 7: S3. 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Google Scholar © 2009 by American Urological AssociationFiguresReferencesRelatedDetailsCited byLerner L, McVary K, Barry M, Bixler B, Dahm P, Das A, Gandhi M, Kaplan S, Kohler T, Martin L, Parsons J, Roehrborn C, Stoffel J, Welliver C and Wilt T (2021) Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA GUIDELINE PART I—Initial Work-up and Medical ManagementJournal of Urology, VOL. 206, NO. 4, (806-817), Online publication date: 1-Oct-2021.Kaplan S (2015) Re: Reasons for Prescription Change of α1-Blockers in Patients with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic HyperplasiaJournal of Urology, VOL. 193, NO. 4, (1317-1317), Online publication date: 1-Apr-2015.Kaplan S (2014) Re: Systematic Review and Meta-Analysis of Randomized Controlled Trials Evaluating Silodosin in the Treatment of Non-Neurogenic Male Lower Urinary Tract Symptoms Suggestive of Benign Prostatic EnlargementJournal of Urology, VOL. 193, NO. 3, (948-949), Online publication date: 1-Mar-2015.Kaplan S (2014) Re: Comparison of 7 α1-Adrenoreceptor Antagonists in Patients with Lower Urinary Tract Symptoms Associated with Benign Prostatic Hyperplasia: A Short-Term Crossover StudyJournal of Urology, VOL. 192, NO. 4, (1166-1167), Online publication date: 1-Oct-2014.Nickel J, O'Leary M, Lepor H, Caramelli K, Thomas H, Hill L and Hoel G (2011) Silodosin for Men With Chronic Prostatitis/Chronic Pelvic Pain Syndrome: Results of a Phase II Multicenter, Double-Blind, Placebo Controlled StudyJournal of Urology, VOL. 186, NO. 1, (125-131), Online publication date: 1-Jul-2011.Kaplan S (2015) Re: Reasons for Prescription Change of α1-Blockers in Patients with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic HyperplasiaJournal of Urology, Related articlesJournal of Urology17 Apr 2009The Role of α1-Adrenoceptor and Arachidonate Pathways in Increased Tone of Demucosalized Bladder TissueJournal of Urology10 Nov 2018Rapid Efficacy of the Highly Selective α1A-Adrenoceptor Antagonist Silodosin in Men With Signs and Symptoms of Benign Prostatic Hyperplasia: Pooled Results of 2 Phase 3 Studies Volume 181Issue 6June 2009Page: 2634-2640 Advertisement Copyright & Permissions© 2009 by American Urological AssociationKeywordsprostatic hyperplasiaKMD 3213signs and symptomsAcknowledgmentsRoland Tacke, PhD and Marsha Hall from Scientific Connexions (Newtown, Pennsylvania) provided assistance with funding from Watson Pharma, Inc.MetricsAuthor Information Leonard S. Marks University of California at Los Angeles and Urological Sciences Research Foundation, Los Angeles, California Financial interest and/or other relationship with Allergan, American Medical Systems, Astellas, Bayer, Beckman Coulter, Diagnostic Ultrasound, GTX, GlaxoSmithKline, Gen-Probe, Indevus, Light Sciences Oncology, Lilly/ICOS, Merck, Novartis, Onconome, Pfizer, Sanofi, Solvay, Watson, National Institutes of Health, CapCURE, Pardee Foundation and Seder Foundation. More articles by this author Marc C. Gittelman South Florida Medical Research, Aventura, Florida Financial interest and/or other relationship with Watson Pharmaceuticals. More articles by this author Lawrence A. Hill Watson Laboratories, Salt Lake City, Utah Financial interest and/or other relationship with Watson Pharmaceuticals. More articles by this author Weining Volinn Watson Laboratories, Salt Lake City, Utah Financial interest and/or other relationship with Watson Pharmaceuticals. More articles by this author Gary Hoel Watson Laboratories, Salt Lake City, Utah Financial interest and/or other relationship with Watson Pharmaceuticals. More articles by this author Expand All Advertisement PDF downloadLoading ...