Comparative rapid onset of efficacy between doxazosin gastrointestinal therapeutic system and tamsulosin in patients with lower urinary tract symptoms from benign prostatic hyperplasia: a multicentre, prospective, randomised study

Aims: To compare the rapidity of improvement in lower urinary tract symptoms (LUTS) for the doxazosin gastrointestinal therapeutic system (GITS) and tamsulosin in benign prostatic hyperplasia (BPH) patients. Methods: A total of 207 patients were randomised to one of two groups for a 12-week daily treatment with doxazosin-GITS 4 mg or tamsulosin 0.2 mg. The primary end-point was to compare the early onsets of efficacy between the two drugs. This was assessed by analysing the changes from baseline in the total International Prostate Symptom Score (IPSS) in the early period of treatment. Secondary aims were to compare improvements in obstructive/irritative subscore and quality of life (QoL) score between the two groups, and to evaluate the adverse events (AEs) with the drugs. Results: After 12 weeks of treatment, both groups showed significant improvements in IPSS scores (total, obstructive and irritative subscores, QoL score) from baseline (p < 0.0001). However, the doxazosin-GITS group showed significantly greater improvements in total IPSS and obstructive subscore than the tamsulosin group in the early period (p < 0.05). Improvements in irritative subscore (within 4 weeks) and QoL score (during 12 weeks) were not significantly different between the groups. The incidences of AEs were similar between the groups. Conclusion: In this study, doxazosin-GITS showed significantly more rapid onset of efficacy and similar AEs compared with tamsulosin in BPH patients with LUTS. We believe this will probably improve patient compliance. Future studies with a larger number of patients and a longer follow-up period will be required to confirm this.