PHILADELPHIA, Jan. 18 A study to be published in theFebruary issue of the Journal of Urology shows that men with enlargedprostates who took a combination of two medications, AVODART (dutasteride) andtamsulosin, experienced significantly greater improvement in urinary symptomsthan men prescribed either medication alone, GlaxoSmithKline said today.
The publication will mark the first time the full two-year results of theCombAT (Combination of Avodart and Tamsulosin) study, one of the largestclinical trials to date of men with enlarged prostate, have appeared in amajor medical journal.(1) Topline results were previously presented inSeptember 2007 at the annual meeting of the Societe Internationale d'Urologiein Paris.
Enlarged prostate (also known as benign prostatic hyperplasia or BPH) is aprogressive disease that affects 50 percent of men over the age of 50 and morethan 90 percent of men over age 80.2 Common symptoms of enlarged prostateinclude frequent and/or urgent urination, which often is excessive at night,incomplete emptying, starting and stopping, and weak stream.(3)
AVODART belongs to a medicine class known as 5-alpha reductase inhibitors(5-ARIs). Over time, Avodart shrinks the prostate, improves symptoms andarrests the enlarged prostate disease process. Tamsulosin is an alpha blocker,a class of medicines that relaxes muscles in the bladder and prostate. Alphablockers provide rapid symptom improvement, but do not reduce prostate size ormodify the disease process.(2) The CombAT study is the first long-termassessment of the combination of AVODART and tamsulosin.(3)
"CombAT is an important contribution to our evolving understanding of themanagement of enlarged prostate," according to Steven A. Kaplan, M.D., fromWeill Cornell Medical College of Cornell University in New York City. Dr.Kaplan authored an editorial comment that will accompany the Journal ofUrology publication of CombAT. "In this study, combination therapy yieldedgreater improvement in symptom score than either monotherapy within the firstyear of treatment, which appears to be a new finding. We then see in CombATthat this treatment difference holds true through Month 24."
In the CombAT study, male patients with moderate-to-severe enlargedprostate symptoms received placebo for four weeks and then were randomized toreceive AVODART and tamsulosin as combination therapy, AVODART as monotherapy,or tamsulosin monotherapy (combination therapy, n=1610; AVODART, n=1623;tamsulosin, n=1611). The primary endpoint was the change in InternationalProstate Symptom Score (IPSS)* score from baseline at Month 24 for combinationtherapy compared to each medication alone.(3)
CombAT results showed at Month 24, that combination therapy demonstratedsignificantly greater symptom improvement for patients than either of themonotherapies (each comparison p<0.001). At Month 24, the mean decrease inIPSS from baseline was 6.2 points for combination therapy compared to 4.9 and4.3 points for AVODART and tamsulosin, respectively.(3)
All therapy regimens employed in the study appear to be generally well-tolerated. Although the total number of drug-related adverse events wassignificantly greater in the combination group compared with eithermonotherapy group, only 5% or less of men in each treatment group withdrewfrom the study as a result of these adverse events. The most common (greaterthan or equal to 2%) adverse events for combination therapy were erectiledysfunction (7.4%), retrograde ejaculation (4.2%), altered or decreased libido(3.4%), and ejaculation failure (2.4%). The most common adverse events forAVODART as monotherapy were erectile dysfunction (6.0%) and altered ordecreased libido (2.8%), and for tamsulosin monotherapy was erectiledysfunction (3.8%).(3)
* The International Prostate Symptom Score (IPSS) is a symptom index forenlarged prostate that was developed