Efficacy and Safety of Hexanic Lipidosterolic Extract of Serenoa repens (Permixon) in the Treatment of Lower Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia: Systematic Review and Meta-analysis of Randomized Controlled Trials

Context: A recent Cochrane Collaboration meta-analysis of randomized controlled trials (RCTs) evaluating the efficacy of different extracts of Serenoa repens in relieving lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) concluded that these extracts were no more effective than placebo. However, among all Serenoa repens extracts, Permixon (Pierre Fabre Medicament, Paris, France) has the highest activity and the most accurate standards of drug preparation and extraction.

Objective: To evaluate the efficacy and safety of Permixon in the treatment of LUTS/BPH.

Evidence acquisition: A systematic review and meta-analysis of the literature was performed in January 2016 using the Medline, Scopus, and Web of Science databases, searching for the term Serenoa repens in all fields of the records. Only RCTs reporting on efficacy and safety of Permixon in the treatment of LUTS/BPH were selected.

Evidence synthesis: The systematic search identified 12 RCTs: 7 compared Permixon with placebo; 2 compared Permixon with tamsulosin; 2 compared Permixon plus tamsulosin with, respectively, placebo plus tamsulosin and tamsulosin alone; and 1 compared Permixon with finasteride. Permixon was significantly more effective than placebo in reducing the number of nocturnal voids (weighted mean difference [WMD] -0.31; p=0.03) and increasing maximum flow rate (Q_max; WMD 3.37; p<0.0001). The rates of overall adverse events (odds ratio [OR] 1.12; p=0.92) and withdrawal (OR 1.52; p=0.60) were similar for Permixon and placebo. Permixon was as effective as tamsulosin monotherapy and short-term therapy with finasteride in improving International Prostate Symptom Score (WMD 1.15; 95% confidence interval [CI], -1.11 to 3.40; p=0.32) and Q_max (WMD -0.16; 95% CI, -0.60 to 0.28; p=0.48). The combination of Permixon and tamsulosin was more effective than Permixon alone for relieving LUTS (WMD 0.31; 95% CI, 0.13-0.48; p<0.01) but not for improving Q_max (WMD 0.10; 95% CI -0.02 to 0.21; p=0.10). Permixon had a favorable safety profile, with a very limited impact with regard to ejaculatory dysfunction compared with tamsulosin (0.5% vs 4%; p=0.007) and with regard to decreased libido and impotence compared with short-term finasteride (2.2% and 1.5% vs 3% and 2.8%, respectively).

Conclusions: The conclusions of the recent Cochrane meta-analysis on Serenoa repens in the treatment of LUTS/BPH apparently do not apply to Permixon. Our meta-analysis showed that Permixon decreased nocturnal voids and Q_max compared with placebo and had efficacy in relieving LUTS similar to tamsulosin and short-term finasteride. Moreover, Permixon had a favorable safety profile with a very limited impact on sexual function, which is significantly affected by all other drugs used to treat LUTS/BPH.

Patient summary: A systematic review of the literature showed that Permixon was effective for relieving urinary symptoms due to prostate enlargement and improving urinary flow compared with placebo. Permixon had efficacy similar to tamsulosin and short-term finasteride in relieving urinary symptoms. Permixon was well tolerated and had a very limited impact on sexual function.