Two-drug combination superior in high-risk BPH patients

May 21, 2008

The combination of dutasteride (Avodart) and tamsulosin (Flomax) provides significantly greater improvement in International Prostate Symptom Score (IPSS) and patient-reported quality of life than either therapy alone in men with BPH who are at increased risk of progression, according to a 2-year analysis of data from the 4-year Combination of Avodart and Tamsulosin (CombAT) trial.

The combination of dutasteride (Avodart) and tamsulosin (Flomax) provides significantly greater improvement in InternationalProstate Symptom Score (IPSS) and patient-reported quality of life than either therapy alone in men with BPH who are atincreased risk of progression, according to a 2-year analysis of data from the 4-year Combination of Avodart and Tamsulosin(CombAT) trial.

CombAT is an ongoing, multicenter, randomized, double-blind, parallel-group study involving nearly 5,000 men.

The data also showed that monotherapy with dutasteride, a 5-alpha-reductase inhibitor, was significantly superior to thealpha-blocker tamsulosin for IPSS reduction in men

"In the higher-volume prostate where the patient is expressing symptoms, combination therapy provides the biggest bang for thebuck," study co-author Jack Barkin, MD, University of Toronto, told attendees at the AUA annual meeting. "What wasinteresting, though, was the fact that for the first time, we see a better IPSS response with the 5-alpha-reductase inhibitorthan we did with the alpha-blocker."

"In patients with larger glands, 5-alpha-reductase inhibitors are not only good for disease modification, but also forsuperior symptom relief and flow-rate improvement," added co-author Claus Roehrborn, MD, University of Texas SouthwesternMedical Center, Dallas.

Of the 4,844 men randomized to treatment in CombAT, 3,822 have completed follow-up through 24 months. All are 50 years orolder with prostate volumes ≥30 cc. They were randomized to once-daily doses of dutasteride, 0.5 mg, tamsulosin, 0.4 mg,or the combination.

Improvement in BPH Impact Index (BII) score from baseline was significantly greater (p<.01) with combination therapyversus dutasteride starting at 3 months, and versus tamsulosin beginning at 9 months. Improvement in IPSS from baseline wassuperior-2.1 on a 6-point scale-with combination therapy at 3 months versus dutasteride and at 12 monthsversus tamsulosin (p<.001).

Combination therapy was superior to either monotherapy in terms of safety in almost all subgroups, regardless of age, race,BMI, symptom score, quality of life score, BII, flow rate, prostate volume, and PSA.

Dr. Barkin is a consultant/adviser and an investigator for Merck. Dr. Roehrborn is a consultant/adviser and investigator forGSK, sanofi-aventis, and Pfizer.