What are the Data on 5α-Reductase Inhibitor Treatment of Benign Prostatic Hyperplasia from Everyday Practice?

The 5α-reductase (5-AR) inhibitors finasteride and dutasteride have been shown to be efficacious and well tolerated in large-scale, randomised, controlled trials (RCTs) of men with symptomatic benign prostatic hyperplasia (BPH). RCTs are the gold standard in therapeutic investigations, providing the most robust scientific evidence for efficacy and safety. However, there has been a resurgence of interest in the value of everyday practice and open-label studies as an adjunct to RCTs. Although such studies provide less robust evidence, the less stringent enrolment criteria allow examination of efficacy in more representative patient populations. Dutasteride has been studied in a French open-label study that enrolled 400 patients. After 24 wk of daily dutasteride treatment, 73% of patients had met the primary end point for a decrease of at least 3 points on the International Prostate Symptom Score. Dutasteride was well tolerated with a low incidence of sexual adverse events. This study therefore demonstrates that dutasteride produces beneficial effects in clinical practice with an acceptable tolerability profile. Insight into the long-term effects of the 5-AR inhibitors in BPH can also be drawn from the open-label extensions of the phase 3 trials of finasteride and dutasteride. These data sets offer an interesting insight into how symptom-based outcome measures are affected by study unblinding, while also providing valuable information to support the long-term safety and sustained efficacy of these drugs.