Mirabegron (Myrbetriq) is effective and well tolerated in patients age 65 or older with overactive bladder (OAB), results of a randomized, placebo-controlled study show.
The beta-3 agonist reduced micturition frequency and incontinence episodes versus placebo in the study, which is the first prospectively designed investigation of the medication specifically in older adults, according to investigator Adrian Wagg, MB BS, of the University of Alberta in Edmonton, Canada.
Treatment was well tolerated and not associated with adverse cognitive effects, Dr. Wagg said at the International Continence Society annual meeting in Philadelphia.
Mirabegron offers an alternative to antimuscarinic agents, which are associated with adverse effects that can limit adherence to treatment, according to Dr. Wagg and co-investigators.
“Overactive bladder is a problem mainly experienced by older people, and we have an alternative for treatment, so we felt it was about time that we trialed this in older people,” Dr. Wagg said in a podium presentation.
The 12-week phase IV, double-blind, randomized PILLAR study included patients at least 65 years of age who had OAB symptoms for at least 6 months. A total of 887 patients, of whom 249 (28.1%) were at least 75 years of age, were randomized to receive mirabegron (n=445) or placebo (n=442).
Patients randomized to receive mirabegron had the option of dose escalation to 50 mg/day, depending on tolerability, Dr. Wagg said.
There was a statistically significant difference in favor of mirabegron for the co-primary endpoints of the study, which were incontinence episodes and number of micturitions per 24 hours from baseline to end of treatment, Dr. Wagg reported.
The mean change in number of incontinence episodes in 24 hours was –1.57 for the placebo arm and –2.06 for the mirabegron arm (p<.001), according to his report. Similarly, the mean change in number of micturitions over 24 hours was reported to be –2.0 for placebo and –2.5 for mirabegron (p<.001).
Patients receiving mirabegron also had a larger change in mean volume voided per micturition from baseline to end of treatment, at 32.44 mL versus 18.49 mL (p<.001), as well as a significantly greater improvement in symptoms as measured by the Overactive Bladder Questionnaire, Dr. Wagg said.