Objectives: To assess the effectiveness and safety of dutasteride 0.5 mg + tamsulosin 0.2 mg combination compared with tamsulosin 0.2 mg in Asian men with moderate-to-severe benign prostatic hyperplasia.
Methods: A 4-week, single-blind, placebo, run-in was followed by a 2-year double-blind randomized controlled trial in men age ≥50 years with symptomatic benign prostatic hyperplasia, International Prostate Symptom Score ≥12, prostate volume ≥30 cc, prostate-specific antigen ≥1.5 and ≤10 ng/mL, peak urinary flow >5 and ≤15 mL/s, and voided volume of ≥125 mL. Participants were randomized to oral daily dutasteride 0.5 mg + tamsulosin 0.2 mg combination or tamsulosin 0.2 mg. The primary efficacy end-point was change in International Prostate Symptom Score at year 2.
Results: Data from 607 participants showed a significant reduction in International Prostate Symptom Score (P < 0.05) at month 24, along with greater improvements (P ≤ 0.006) in peak urinary flow at every assessment and significant prostate volume reduction at months 12 and 24 (P < 0.001) in the combination group. Combination therapy was associated with a significant reduction in the risk of acute urinary retention or benign prostatic hyperplasia-related surgery (P = 0.012), primarily due to a significant reduction in the risk of acute urinary retention (P = 0.005). The safety and tolerability profile of combination therapy was consistent with the known profiles for the individual monotherapies.
Conclusions: Dutasteride 0.5 mg + tamsulosin 0.2 mg combination therapy showed better clinical outcomes than tamsulosin 0.2 mg monotherapy, making it an effective and safe treatment option for Asian men with moderate-to-severe benign prostatic hyperplasia.
Keywords: International Prostate Symptom Score; benign prostatic hyperplasia; combination therapy; dutasteride; tamsulosin.
© 2018 The Japanese Urological Association.