Comparison of the response to treatment between Asian and Caucasian men with benign prostatic hyperplasia: long-term results from the combination of dutasteride and tamsulosin study.

The Combination of Avodart and Tamsulosin study was a 4-year, randomized, double-blind study of the efficacy and safety of dutasteride and tamsulosin, alone or in combination, in men with moderate-to-severe benign prostatic hyperplasia. In this post-hoc investigation, we analyzed primary and secondary end-points from the Combination of Avodart and Tamsulosin study in Asian (n = 325) and Caucasian men (n = 4259). The incidence of acute urinary retention or benign prostatic hyperplasia-related surgery did not differ significantly between treatment groups in the Asian subpopulation. In Caucasian men, the incidence of acute urinary retention/benign prostatic hyperplasia-related surgery was significantly lower in the combination therapy group compared with the tamsulosin monotherapy group (P < 0.001), but not compared with dutasteride monotherapy. Combination therapy significantly increased the time to benign prostatic hyperplasia clinical progression and resulted in improved International Prostate Symptom Score, maximum urinary flow rate, quality of life, and reduced prostate volume in Asian and Caucasian men who received combination therapy compared with tamsulosin monotherapy. Combination therapy also significantly improved (P < 0.05) time to benign prostatic hyperplasia clinical progression, International Prostate Symptom Score, maximum urinary flow rate and quality of life versus dutasteride in the Caucasian subpopulation. The adverse-event profile was comparable between subpopulations. In conclusion, Asian and Caucasian men respond similarly to these treatments, despite apparent racial differences in 5α-reductase activity.

The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study.

BACKGROUND: Combination therapy with dutasteride and tamsulosin provides significantly greater benefit than either monotherapy for various patient-reported outcomes in men with moderate-to-severe lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) and prostatic enlargement. OBJECTIVE: To investigate whether combination therapy is more effective than either monotherapy in reducing the relative risk for acute urinary retention (AUR), BPH-related surgery, and BPH clinical progression over 4 yr in men at increased risk of progression. DESIGN, SETTING, AND PARTICIPANTS: The Combination of Avodart and Tamsulosin (CombAT) study was a 4-yr, multicenter, randomised, double-blind, parallel-group study in 4844 men > or =50 yr of age with a clinical diagnosis of BPH, International Prostate Symptom Score > or =12, prostate volume > or =30 cm(3), prostate-specific antigen 1.5-10 ng/ml, and maximum urinary flow rate (Q(max)) >5 and < or =15 ml/s with minimum voided volume > or =125 ml. INTERVENTION: Oral daily tamsulosin, 0.4 mg; dutasteride, 0.5 mg; or a combination of both. MEASUREMENTS: The 4-yr primary end point was time to first AUR or BPH-related surgery. Secondary end points included BPH clinical progression, symptoms, Q(max), prostate volume, safety, and tolerability. RESULTS AND LIMITATIONS: Combination therapy was significantly superior to tamsulosin monotherapy but not dutasteride monotherapy at reducing the relative risk of AUR or BPH-related surgery. Combination therapy was also significantly superior to both monotherapies at reducing the relative risk of BPH clinical progression. Combination therapy provided significantly greater symptom benefit than either monotherapy at 4 yr. Safety and tolerability of combination therapy was consistent with previous experience with dutasteride and tamsulosin monotherapies, with the exception of an imbalance in the composite term of cardiac failure among the three study arms. The lack of placebo control is a study limitation. CONCLUSIONS: The 4-yr CombAT data provide support for the long-term use of dutasteride and tamsulosin combination therapy in men with moderate-to-severe LUTS due to BPH and prostatic enlargement. CLINICALTRIALS.GOV IDENTIFIER: NCT00090103 (http://www.clinicaltrials.gov/ct2/show/NCT00090103).

The effects of dutasteride, tamsulosin and combination therapy on lower urinary tract symptoms in men with benign prostatic hyperplasia and prostatic enlargement: 2-year results from the CombAT study.

PURPOSE: We investigated whether combination therapy with dutasteride and tamsulosin is more effective than either monotherapy alone for improving symptoms and long-term outcomes in men with moderate to severe lower urinary tract symptoms and prostatic enlargement (30 cc or greater). We report preplanned 2-year analyses. MATERIALS AND METHODS: The CombAT study is an ongoing, multicenter, randomized, double-blind, parallel group study. Men 50 years or older with a clinical diagnosis of benign prostatic hyperplasia, International Prostate Symptom Score 12 points or greater, prostate volume 30 cc or greater, total serum prostate specific antigen 1.5 ng/ml or greater to 10 ng/ml or less and peak urinary flow greater than 5 to 15 ml per second or less with a minimum voided volume of 125 ml or greater were randomized to 0.5 mg dutasteride, 0.4 mg tamsulosin or the combination once daily for 4 years. Symptoms were assessed every 3 months and peak urinary flow was assessed every 6 months. The primary end point at 2 years was the change in International Prostate Symptom Score from baseline. RESULTS: Combination therapy resulted in significantly greater improvements in symptoms vs dutasteride from month 3 and tamsulosin from month 9, and in benign prostatic hyperplasia related health status from months 3 and 12, respectively. There was a significantly greater improvement from baseline in peak urinary flow for combination therapy vs dutasteride and tamsulosin monotherapies from month 6. There was a significant increase in drug related adverse events with combination therapy vs monotherapies, although most did not result in the cessation of therapy. CONCLUSIONS: In men with moderate to severe lower urinary tract symptoms and prostate enlargement (30 cc or greater) combination therapy provides a significantly greater degree of benefit than tamsulosin or dutasteride monotherapy.

Combination therapy with dutasteride and tamsulosin in men with moderate-to-severe benign prostatic hyperplasia and prostate enlargement: the CombAT (Combination of Avodart and Tamsulosin) trial rationale and study design.

Benign prostatic hyperplasia (BPH) is a highly prevalent condition in aging men, which can be progressive and lead to acute urinary retention (AUR) and the need for surgery. It is commonly treated with alpha-blockers and 5alpha-reductase inhibitors (5ARIs), both of which improve the symptoms of BPH. Long-term treatment with 5ARIs can also reduce the risk of developing AUR and the need for surgery. The landmark Medical Therapy of Prostatic Symptoms (MTOPS) trial demonstrated that over 4 years the combination of the type 2-specific 5ARI, finasteride and the alpha-blocker doxazosin was more effective than either agent alone in reducing overall clinical progression. Since the initiation of MTOPS, it has been shown that patients with larger prostates and higher prostate-specific antigen (PSA) levels are at greater risk of BPH progression, and are therefore arguably more likely to benefit from combination therapy. The Combination of Avodart and Tamsulosin (CombAT) trial is a 4-year, global, multicenter, randomized, double-blind, parallel-group study designed to investigate the benefits of combination therapy with the dual 5ARI dutasteride and the alpha-blocker tamsulosin compared with each monotherapy in improving symptoms and long-term outcomes in men with moderate-to-severe symptoms of BPH and prostate enlargement. Symptoms and long-term outcomes (AUR and surgery) will be assessed as separate primary endpoints at 2 and 4 years, respectively. Eligible patients were at least 50 years old with prostate volume > or =30 cm(3) and PSA level > or =1.5 ng/mL. A total of 4838 subjects have been enrolled. This paper describes the rationale, design and baseline data of the CombAT study.