12-month follow-up study to evaluate the efficacy and safety of Doxazosin GITS in patients with benign prostatic hyperplasia

Purpose: The aim of this study was to assess the long-term efficacy and safety of doxazosin gastrointestinal therapeutic system (GITS) in Korean patients with benign prostatic hyperplasia (BPH) under usual care conditions. Materials and methods: In this a 12-month, open-label, multicenter, non-controlled, flexible-dose study, 475 men (≥40 years), with clinical evidence of BPH, were enrolled from 40 centers. Patients were evaluated at the baseline, and at 1, 2 and 6 months for dose adjustment, based on their treatment response (efficacy), and 12 months to assess the final efficacy. The primary efficacy variable was the Clinician's Global Assessment of Change (CGAC; improved, no change, or worse) and the secondary were the International Prostate Symptom Score (IPSS), quality of life (QoL), maximum flow rate (Qmax) and post void residual (PVR). The adverse events (AEs) and blood pressure (BP) were also recorded. Results: 186 patients completed the study. Most patients (n=155; 83.8%) improved, but 31 (16.2%) had no change in symptoms based on the CGAC. The mean changes in the IPSS and QoL from the baseline were -9.0±6.8 and -1.6±1.4, respectively (both p < 0.05). The Qmax and PVR were significantly improved compared with the baseline (Qmax 10.5±4.3 vs. 13.7±6.3, PVR 39.1±37.0 vs. 23.2±33.7, p < 0.05). The decrease in the systolic and diastolic BP from the baselines in hypertensive patients (n=52) was significantly greater than in normotensive patients (n=134) (SBP/DBP -9.5±18.4/-13.4±10.9 vs. -3.3±12.5/-1.4±9.5, p < 0.05). A total of 34 AEs related to the medication were reported (7.1%). The most frequently reported AEs were dizziness (2.7%), impotence (1.1%), dry mouth (0.8%) and postural hypotension (0.4%). Conclusions: Treatment with doxazosin GITS for 12 months resulted in significant improvements in the IPSS, QoL, Qmax and PVR, demonstrating its effectiveness and good tolerability as a long-term therapy for Korean BPH patients.