Efficacy and Safety of a Fixed-Dose Combination Therapy of Tamsulosin and Tadalafil for Patients With Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Randomized, Double-Blinded, Active-Controlled Trial

Phosphodiesterase type 5 inhibitors and α-adrenergic blocking agents (α-blockers) are widely used for the treatment of erectile dysfunction (ED) and lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH).

To assess the efficacy and safety of fixed-dose combinations (FDCs) of tamsulosin and tadalafil compared with tadalafil monotherapy in patients with comorbid BPH-associated LUTS and ED.

A randomized, double-blinded, active-controlled trial was conducted of 510 men with BPH-associated LUTS and ED. Patients were treated with FDCs of tamsulosin 0.4 mg plus tadalafil 5 mg (FDC 0.4/5 mg), tamsulosin 0.2 mg plus tadalafil 5 mg (FDC 0.2/5 mg), or tadalafil 5 mg for a 12-week treatment period. For a subsequent 12-week extension period, the patients were administered FDC 0.4/5 mg.

The primary outcomes were changes from baseline in total International Prostate Symptom Score (IPSS) and International Index of Erectile Function erectile function domain (IIEF-EF) score at week 12 to prove superiority and non-inferiority of FDCs compared with tadalafil 5 mg. The safety assessments were adverse reactions, laboratory test results, and vital signs at week 24.

The mean changes in total IPSS and IIEF-EF scores were -9.46 and 9.17 for FDC 0.4/5 mg and -8.14 and 9.49 for tadalafil 5 mg, respectively, which indicated superiority in LUTS improvement (P = .0320) and non-inferiority in ED treatment with FDC 0.4/5 mg compared with tadalafil 5 mg. However, the results from FDC 0.2/5 mg failed to demonstrate superiority in LUTS improvement. No clinically significant adverse events regarding the investigational products were observed during the 24-week period.

The FDC 0.4/5 mg is the first combined formulation of an α-blocker and a phosphodiesterase type 5 inhibitor that offers benefits in patient compliance and as add-on therapy in patients with comorbid BPH-associated LUTS and ED.

The study clearly demonstrated the advantage of FDC 0.4/5 mg. The main advantage of FDC 0.4/5 mg was the enhanced efficacy on BPH-associated LUTS comorbidity with ED, the lower incidence of side effects, and the simplification and convenience of therapy, which led to better overall patient compliance. However, the lack of a tamsulosin monotherapy control group was a limitation of this study.

The FDC 0.4/5 mg therapy was safe, well tolerated, and efficacious, indicating that combination therapy could provide clinical benefits for patients with BPH-associated LUTS complaints and ameliorate the comorbidity of ED. Kim SW, Park NC, Lee SW, et al. Efficacy and Safety of a Fixed-Dose Combination Therapy of Tamsulosin and Tadalafil for Patients With Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Randomized, Double-Blinded, Active-Controlled Trial. J Sex Med 2017;14:1018-1027.

The journal of sexual medicine. 2017 Aug [Epub]

Sae Woong Kim, Nam Cheol Park, Seung Wook Lee, Dae Yul Yang, Jong Kwan Park, Du Geon Moon, Sang-Kuk Yang, Sung Won Lee, Ki Hak Moon, Tai Young Ahn, Soo Woong Kim, Kwangsung Park, Kweon Sik Min, Ji-Kan Ryu, Hankil Son, Jina Jung, Jae Seog Hyun

Department of Urology, The Catholic University College of Medicine, Seoul, Korea., Department of Urology, Pusan National University School of Medicine, Busan, Korea., Department of Urology, Hanyang University College of Medicine, Seoul, Korea., Department of Urology, Hallym University College of Medicine, Seoul, Korea., Department of Urology, Chonbuk National University Medical School, Jeonju, Korea., Department of Urology, Korea University College of Medicine, Seoul, Korea., Department of Urology, Konkuk University School of Medicine, Seoul, Korea., Department of Urology, Sungkyunkwan University School of Medicine, Seoul, Korea., Department of Urology, Yeungnam University College of Medicine, Daegu, Korea., Department of Urology, Ulsan University College of Medicine, Seoul, Korea., Department of Urology, Seoul National University College of Medicine, Seoul, Korea., Department of Urology, Chonnam National University Medical School, Gwangju, Korea., Department of Urology, Inje University College of Medicine, Busan, Korea., Department of Urology, Inha University School of Medicine, Incheon, Korea., Clinical Research Team, Hanmi Pharmaceutical Co, Ltd, Seoul, Korea., Department of Urology, Gyeongsang National University College of Medicine and Hospital, Jinju, Korea. Electronic address: .