Efficacy and safety of combination therapy with tamsulosin, dutasteride and imidafenacin for the management of overactive bladder symptoms associated with benign prostatic hyperplasia: A multicenter, randomized, open-label, controlled trial (DIrecT Study)

Objectives: To evaluate the efficacy and safety of a combination therapy with dutasteride and imidafenacin in patients with benign prostatic hyperplasia and persistent overactive bladder symptoms. Methods: A total of 163 patients presenting an enlarged prostate (volume >30 mL) and persistent overactive bladder symptoms despite at least 8 weeks of tamsulosin were randomized to receive tamsulosin and dutasteride, or tamsulosin, dutasteride and imidafenacin at a 1:1 ratio. The primary end-point was the mean change from baseline to week 24 in total overactive bladder symptom score. Results: The mean change in total overactive bladder symptom score from baseline at week 24 was −1.99 (95% confidence interval −2.57 to −1.41) in the tamsulosin and dutasteride group, and −3.12 (95% confidence interval −3.72 to −2.52) in the tamsulosin, dutasteride and imidafenacin group. The tamsulosin, dutasteride and imidafenacin group significantly improved total overactive bladder symptom score at week 24 as compared with the tamsulosin and dutasteride group; the mean difference was −1.18 (−2.02 to −0.34). The between-group difference was statistically significant as early as week 4. The total International Prostate Symptom Score, storage subscore, quality of life index, and benign prostatic hyperplasia impact index also significantly improved in the tamsulosin, dutasteride and imidafenacin group. Conclusions: Tamsulosin, dutasteride and imidafenacin combination therapy improves overactive bladder symptoms and quality of life without causing serious adverse drug reactions in patients with enlarged prostate not responding to tamsulosin. This combination therapy seems to represent a promising therapeutic option in these patients.