Which Drug to Discontinue 3 Months After Combination Therapy of Tadalafil plus Tamsulosin for Men with Lower Urinary Tract Symptom and Erectile Dysfunction? Results of a Prospective Observational Trial.

BACKGROUND

Safety and efficacy of tamsulosin and tadalafil for men with benign prostatic enlargement (BPE) and/or erectile dysfunction (ED) are defined. However, there are only a few pilot studies on combination therapy with these drugs for men with lower urinary tract symptom (LUTS)/BPE and ED. Moreover, preliminary reports are limited to 12 wk, without any information about subsequent therapies.

OBJECTIVE

To evaluate the impact of discontinuation of tamsulosin versus tadalafil 12 wk after combination therapy.

DESIGN, SETTING, AND PARTICIPANTS: Fifty consecutive patients with moderate-to-severe LUTS (International Prostate Symptom Score [IPSS] > 7) and mild-to-severe ED (International Index of Erectile Function-5 [IIEF-5] < 22) were treated with combination therapy (tamsulosin 0.4mg/d plus tadalafil 5mg/d) for 12 wk. After 12 wk, 25 patients discontinued tamsulosin (Group TAD), while 25 patients discontinued tadalafil (Group TAM).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Efficacy variables were IPSS (total, voiding, storage) and IIEF-5. Paired samples t test and analysis of variance were used.

RESULTS AND LIMITATIONS

Groups TAD and TAM presented similar features (age, BMI, metabolic profile) including symptoms scores at baseline. Similar and significant improvements in IPSS (total, voiding, and storage) and IIEF-5 were recorded in both groups after 12 wk of combination therapy (all p< 0.001). Total IPSS was similar between the two groups at the end of the trial. However, we found between-group significant differences from baseline to 24 wk and from 12 to 24 wk in storage-IPSS (Group TAD: -3.32 vs Group TAM: -1.24, p= 0.002; Group TAD: +0.24 vs Group TAM: +1.20, p= 0.040, respectively) and in IIEF-5 (Group TAD: +4.64 vs Group TAM: +0.16, p< 0.001; Group TAD: -1.64 vs Group TAM: -4.40, p= 0.003). No significant treatment-related adverse event was recorded in both groups.

CONCLUSIONS

After 12 wk of combination therapy, monotherapy with tadalafil for further 12 wk allows to preserve the improvement of storage IPSS and IIEF-5, in addition to total IPSS.

PATIENT SUMMARY

In this report we evaluated the discontinuation of tamsulosin or tadalafil after 12 wk of combination therapy. We found that tadalafil monotherapy, for a further 12 wk, aids in retaining the improvement of storage symptoms and erectile function.