Comparison of Silodosin Monotherapy Versus Silodosin with Tadalafil Add-on Therapy in Patients with Benign Prostatic Hyperplasia

To evaluate the efficacy and safety of add-on therapy with the phosphodiesterase type 5 inhibitor tadalafil for patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia (LUTS/BPH) treated with the α1-adrenoceptor blocker silodosin.

We analyzed 103 patients with LUTS/BPH with an International Prostate Symptom Score (IPSS) of >8 after ≥4 weeks of silodosin treatment from April 2016 through December 2016 at Kori Hospital. The patients subsequently received silodosin 4.0 mg twice daily (monotherapy group) or silodosin 4.0 mg twice daily plus tadalafil 5.0 mg once daily (add-on therapy group) for 8 weeks. We assessed adverse events (AEs) and evaluated the mean change from baseline to 8 weeks in the IPSS, Overactive Bladder Symptom Score (OABSS), maximum urine flow rate (Qmax), and post-void residual urine volume (PVR).

Of 103 patients, 101 (98.1%) could continue medical treatment. The IPSS, OABSS, and Qmax showed significantly greater improvement in the add-on therapy than monotherapy group (-3.92 vs. -1.24, -1.18 vs. 0.10, and 1.09 vs. -1.04, respectively; all P<0.05). Although four patients experienced AEs (add-on therapy: n=3, 5.7%; monotherapy: n=1, 2.0%), no significant differences were observed (P=0.62). Among patients with overactive bladder (n=55), the IPSS storage symptom subscore, IPSS urgency subscore, and OABSS urgency subscore showed significantly greater improvement in the add-on therapy than monotherapy group (-2.23 vs. 0.17, -0.88 vs. 0.28, and -1.5 vs. -0.48, respectively; all P<0.05).

Add-on therapy with tadalafil may be effective for patients with LUTS/BPH resistant to silodosin monotherapy.

Urology. 2017 Apr 18 [Epub ahead of print]

Takashi Yoshida, Hidefumi Kinoshita, Seiji Shimada, Makoto Taguchi, Tadashi Matsuda

Department of Urology and Andrology, Kori Hospital, Kansai Medical University, Osaka, Japan., Department of Urology and Andrology, Kansai Medical University Hospital, Osaka, Japan., Department of Urology and Andrology, Kansai Medical University Hospital, Osaka, Japan. Electronic address: .