Clinical Efficacy of Serenoa repens Versus Placebo Versus Alpha-blockers for the Treatment of Lower Urinary Tract Symptoms/Benign Prostatic Enlargement: A Systematic Review and Network Meta-analysis of Randomized Placebo-controlled Clinical Trials

Abstract

Context: International guidelines do not make any specific recommendations on Serenoa repens (SeR) for the treatment of male lower urinary tract symptoms (LUTS) secondary to benign prostatic enlargement (BPE), due to product heterogeneity and methodological limitations of the published trials and meta-analyses.

Objective: We aimed to compare the clinical efficacy of hexanic extract of SeR (HESr) versus non-HESr (nHESr) versus placebo versus alpha-blockers (ABs) in patients affected by LUTS secondary to BPE through a network meta-analysis method.

Evidence acquisition: The search was conducted until December 31, 2018 using Medline, Scopus, and Web of Science databases without restriction. We included randomized controlled trials (RCTs) with at least one comparison between SeR, ABs, or placebo for the treatment of LUTS/BPE. Outcomes of the study were the mean change in the International Prostate Symptom Score (IPSS) and peak flow (PF). This systematic review has been registered on PROSPERO (CRD42018084360).

Evidence synthesis: In total, 2115 articles were identified. After the global assessment, 22 RCTs matched with the inclusion criteria, including 8564 patients. For IPSS, the mean efficacies against placebo were +0.48 and -1.69 for HESr and nHESr, respectively, at 3 mo; 0.59 for nHESr at 6 mo; and -1.31 and -3.30 for nHESr and HESr, respectively, at 12 mo. For PF, the mean efficacies against placebo were +0.53 and +2.82 for HESr and nHESr, respectively, at 3 mo; +1.85 for nHESr at 6 mo; and +4.05 and +5.52 for HESr and nHESr, respectively, at 12 mo. Based on the surface under the cumulative ranking curve rankograms, terazosin showed the highest score (99.6%), while alfuzosin, tamsulosin, silodosin, HESr, and nHESr showed scores of 53.7%, 42.3%, 68.5%, 36.7%, and 47.3%, respectively.

Conclusions: In this network meta-analysis, we demonstrated that SeR did not show clinically meaningful improvement in LUTS and PF.

Patient summary: In the present study, we found no clinically meaningful improvement of Serenoa repens for the treatment of lower urinary tract symptoms/benign prostatic enlargement. The analysis showed that the benefit over placebo was minimal and may not justify its clinical use before higher level of evidence will be available.

Keywords: Benign prostatic hyperplasia; Lower urinary tract symptoms; Medical therapy; Phytotherapy; Prostate; Saw palmetto.