Objectives: To evaluate the effects of finasteride, a specific type II 5-alpha-reductase inhibitor, on symptoms of benign prostatic hyperplasia, prostate volume, and urinary flow during a 7 to 8-year period.
Methods: A total of 190 men with symptomatic benign prostatic hyperplasia and enlarged prostates entered one of two Phase II double-blind 3 to 6-month studies. Of these, 156 patients continued taking open-label finasteride, and more than 70 patients completed 7 to 8 years of treatment. The symptoms were scored using a patient self-administered modified Boyarsky symptom questionnaire. Prostate volume was measured by magnetic resonance imaging or ultrasonography, and the maximal urinary flow rate was assessed noninvasively.
Results: Treatment with finasteride for 7 to 8 years led to sustained improvement in symptoms, reduction in prostate volume (28% from baseline), and increased urinary flow (median 2.5 mL/s from baseline). Decreases in dihydrotestosterone (86%) and prostate-specific antigen (54%) levels were also maintained. Long-term finasteride treatment was safe and generally well tolerated.
Conclusions: Long-term treatment with finasteride was well tolerated and resulted in durable symptom relief and improvement in prostate volume and urinary flow.