Objectives: To evaluate the incidence and resolution of sexual adverse experiences (AEs) in men with benign prostatic hyperplasia treated with finasteride 5 mg compared with placebo.
Methods: The Proscar Long-term Efficacy and Safety Study (PLESS) was a 4-year, randomized, double-blind, placebo-controlled trial assessing the efficacy and safety of finasteride 5 mg in 3040 men, aged 45 to 78 years, with symptomatic benign prostatic hyperplasia, enlarged prostates, and no evidence of prostate cancer. Patients completed a questionnaire at screening regarding their history of sexual dysfunction. During treatment, spontaneously self-reported sexual AEs were recorded.
Results: At screening, 46% of patients in each treatment group reported some history of sexual dysfunction. During year 1 of the study, 15% of finasteride-treated patients and 7% of placebo-treated patients had sexual AEs that were considered drug related by the investigator (P <0.001). During years 2 to 4, no between-group difference was noted in the incidence of new sexual AEs (7% in each group). The drug-related sexual AE profile for finasteride was similar for men with or without a history of sexual dysfunction. Sexual AEs resolved while continuing therapy in 12% of finasteride patients and 19% of placebo patients. Only 4% of finasteride and 2% of placebo patients discontinued the study because of sexual AEs. In men who discontinued with a sexual AE, 50% and 41% experienced resolution of their sexual AE after discontinuing finasteride or placebo therapy, respectively.
Conclusions: Compared with placebo, men treated with finasteride experienced new drug-related sexual AEs with an increased incidence only during the first year of therapy.