Mirabegron improves the symptoms of overactive bladder in patients with Parkinson’s disease

This study investigated the effectiveness and safety of mirabegron (Mirbetriq) for patients with Parkinson’s disease (PD) with overactive bladder (OAB) symptoms. Researchers suggested that mirabegron improved the symptoms of these patients.

PD affects brain cells. Over time, these patients experience a variety of symptoms including urinary symptoms. The most common urinary symptoms are urgency, frequency, and nocturia (waking up at night to urinate). Urinary incontinence (leakage of urine) may also be present. These symptoms are common in OAB syndrome. Urinary symptoms combined with physical symptoms such as impaired walking significantly decrease the quality of life of patients.

Mirabegron is a standard treatment for OAB. Prior studies on mirabegron in patients with PD did not include a placebo group for comparison. Therefore, the true effectiveness of mirabegron in patients with PD and OAB is still not clear.

This study included information about 117 patients with PD and OAB symptoms. After a period of 2 weeks without any OAB medications, participants were assigned to receive either placebo or mirabegron. A follow-up visit was performed at 4 weeks and 8 weeks of treatment. After this, both groups received mirabegron for the rest of the study period (week 12).

After 4 and 8 weeks, both groups had significantly improved OAB symptoms. However, the placebo group had significantly higher OAB symptoms compared to the mirabegron groups at both visits. In the mirabegron group, urinary symptoms improvements were maintained at weeks 4, 8, and 12. At 12 weeks, the OAB symptoms were similar between groups, after mirabegron was given to patients in the placebo group also. 

Side effects were observed in 32.2% of patients in the placebo group and 24.1% of the mirabegron group. Mose side effects were mild. 

This study concluded that mirabegron is a good treatment option for patients with Parkinson’s disease and overactive bladder, with manageable side effects.

This study did not compare mirabegron to other medications of the same type. This study was funded by Astellas Pharma, the mirabegron manufacturer.