AUA 2018: Efficacy and Safety of Add-on Mirabegron vs Placebo to Tamsulosin in Men with Overactive Bladder Symptoms MATCH Study

San Francisco, CA ( Benign prostatic hyperplasia (BPH) is a common condition that affects men, and can be associated with secondary overactive bladder (OAB) symptoms. Alpha blockers such as tamsulosin are widely prescribed for the treatment of BPH, but OAB symptoms may continue to persist. Consequently, patients may still complain of voiding symptoms even with an alpha blocker, affecting the quality of life. 

The MATCH study was a 12-week randomized, double-blind, placebo-controlled study in Japan and Korea composed of male patients ≥40 years who had OAB symptoms despite receiving tamsulosin for BPH. The objective of the study was to assess the efficacy and safety of mirabegron vs. placebo on OAB symptoms in men who were treated with tamsulosin for BPH. The primary endpoint evaluating the change in the mean number of micturitions over a 24 hour period compared to baseline, with secondary endpoints including changes in the number of urgency episodes, mean volume voided, and OAB symptoms based on validated questionnaires.  Safety assessments were also evaluated. Hidehiro Kakizaki, MD, PhD, of the Asahikawa Medical University in Japan, presented the results of the multinational study in a late-breaking abstract on Sunday. 

After a 4-week single-blind screening period in which patients received placebo and tamsulosin, patients were randomized to mirabegron 50 mg or placebo plus tamsulosin for 12 weeks. Data regarding voiding symptoms were collected from 3-day voiding diaries that were collected at baseline and at each follow-up visit which were separated by 4 weeks. Both treatment groups were similarly matched in terms of age, ethnicity, BMI, prostate volume, and Qmax. 

Of the 565 patients included in the final analysis, the mirabegron arm was found to have a significantly decrease in micturitions over a 24 hour period compared to baseline (-1.27 in the mirabegron group vs. -0.75 for the placebo group, with a statistically significant adjusted mean difference between groups (-0.52; P<0.001). Compared to the placebo arm, the mirabegron group also had significant increases in mean volume voided per micturition (p<0.001); improvement in OABSS total scores (p<0.001), symptom bother in OAB-q scores (p<0.001), and total health-related quality of life in OAB-q scares (p<0.001); and IPSS total scores (p<0.002). However, differences between mirabegron and placebo groups were not statistically significant for urgency, urgency incontinence, incontinence and nocturia episodes. 

Regarding safety measures, 23.4% of mirabegron vs. 22.5% of placebo patients reported at least one treatment emergent adverse events (TEAE), with 3.9% of mirabegron and 6.3% of placebo patients reporting a drug-related TEAE. There were no major safety concerns regarding urinary retention or cardiovascular events, but 6.4% of the mirabegron group complained of nasopharyngitis (compared to 6.0% of the placebo group).

Based on the results of the MATCH study, it appears that the addition of mirabegron 50 mg once daily for 12 weeks showed superior efficacy compared to placebo in improving voiding patterns in men with OAB who were already on tamsulosin for BPH. Mirabegron was shown to decrease the frequency and increase volumes voided, with improvements in quality of life scores. 

Presented by: Hidehiro Kakizaki, MD, PhD, Department of Renal and Urologic Surgery, Asahikawa Medical University
Co-Authors: Asahikawa, Japan, Kyu-Sung Lee, Seoul, Korea, Republic of, Osamu Yamamoto, Ibaraki, Japan, Jar Jar Jong, Singapore, Singapore, Daisuke Katou, Budiwan Sumarsono, Satoshi Uno, Tokyo, Japan, Osamu Yamaguchi, Koriyama, Japan

Written by: Judy Choi, MD, Assistant Professor, Department of Urology, University of California, Irvine @judymchoi at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA