The Efficacy of a Combination of Phosphodiesterase Type 5 Inhibitor and Testosterone Replacement Therapy in Nonresponders to Phosphodiesterase Type 5 Inhibitor Mono-therapy

Park, Min Gu; Park, Se Hong; Ko, Ki Won; Ham, Byung Kuk; Kim, Je Jong; Moon, Du Geon

Abstract

PURPOSE
The aim of this study was to evaluate the efficacy of a combination therapy with PDE5 inhibitor and testosterone replacement therapy in erectile dysfunction patients with testosterone deficiency syndrome (TDS) after failure of PDE5 inhibitor mono-therapy.
MATERIALS AND METHODS
From March 2004 to July 2008, we evaluated 38 men (aged 38 to 69 years) who showed no response to PDE5 inhibitor therapy at the maximal recommended dose and they had testosterone levels less than 350ng/dL. Testosterone replacement therapy (TRT) was subsequently started with injectable testosterone undecanoate (NEBIDO(R)) or transdermal testosterone (Testogel(R)) in those patients. They received TRT during an 18-week period. After 14 weeks of TRT alone, PDE5 inhibitor was added to the TRT for an additional 4 weeks. After treatment, we evaluated the patients' sexual function, which was primarily based on the International Index of Erectile Function (IIEF), and the serum testosterone levels.
RESULTS
All patients showed elevated serum testosterone levels after TRT (range: 212 to 662ng/dl, mean level: 362.19 ng/dl). At week 18, almost all of the men reported improved potency with combination therapy. After treatment, the mean total IIEF score and each sub-domain score were increased significantly compared to the baseline score.
CONCLUSIONS
Testosterone replacement therapy combined with PDE5 inhibitor may be beneficial in improving the erectile function in testosterone deficiency syndrome patients with erectile dysfunction and who are unresponsive to PDE5 inhibitor alone.