Mirabegron in the treatment of overactive bladder

Safety and efficacy of beta-3 adrenergic agonists in treating neurogenic lower urinary tract dysfunction: A systematic review and meta-analysis

PURPOSE

To evaluate efficacy and safety of beta-3 adrenergic agonists in adults with neurogenic lower urinary tract dysfunction.

MATERIALS AND METHODS

According to a protocol (CRD42022350079), we searched multiple data sources for published and unpublished randomized controlled trials (RCTs) up to 2nd August 2022. Two review authors independently screened studies and abstracted data from the included studies. We performed statistical analyses by using a random-effects model and interpreted them according to the Cochrane Handbook for Systematic Reviews of Interventions. We used GRADE guidance to rate the certainty of evidence (CoE).

RESULTS

We found data to inform two comparisons: beta-3 adrenergic agonists versus placebo (4 RCTs) and anticholinergics (2 RCTs). Only mirabegron was used for intervention in all included studies. Compared to placebo, beta-3 adrenergic agonists may have a clinically unimportant effect on urinary symptoms score (mean difference [MD] -2.50, 95% confidence interval [CI] -4.78 to -0.22; I²=92%; 2 RCTs; 192 participants; low CoE) based on minimal clinically important difference of 3. We are very uncertain of the effects of beta-3 adrenergic agonists on quality of life (MD 10.86, 95% CI 1.21 to 20.50; I²=41%; 2 RCTs; 98 participants; very low CoE). Beta-3 adrenergic agonists may result in little to no difference in major adverse events (cardiovascular adverse events) (risk ratio 0.57, 95% CI 0.14 to 2.37; I²=0%; 4 RCTs; 310 participants; low CoE). Compared to anticholinergics, no study reported urinary symptom scores and quality of life. There were no major adverse events (cardiovascular adverse events) in either study group (1 study; 60 participants; very low CoE).

CONCLUSIONS

Compared to placebo, beta-3 adrenergic agonists may have similar effects on urinary symptom scores and major adverse events. There were uncertainties about their effects on quality of life. Compared to anticholinergics, we are either very uncertain or have no evidence about urinary symptom scores, quality of life, and major adverse events.

Mirabegron improves erectile function in men with overactive bladder and erectile dysfunction: a 12-week pilot study

Phosphodiesterase type 5 inhibitors (PDE5i) is the only approved oral treatment for erectile dysfunction (ED) in the US, and alternative management remains necessary when this treatment fails or is contraindicated. Targeting other pathways than the NO-cGMP pathway and/or combining this approach with PDE5i may introduce new treatments for men who are unresponsive to PDE5i. This study aims to evaluate whether Mirabegron improves erectile function in men with concurrent overactive bladder and mild to moderate ED. Twenty subjects, 40-70 years old, registering International Index of Erectile Function (IIEF) score 11-25 and International Prostate Symptom Score 8-20, were treated with Mirabegron therapy for 12 weeks. Study participants were re-administered IIEF and OAB-q questionnaires on weeks 2, 4, 8, and 12 and assessed for adverse events. The primary and secondary endpoints were an increase in the IIEF-5 score of 4 units and a decrease in the Overactive Bladder questionnaire (OAB-q) symptom severity score of 10 units between study time points. Thirteen men completed the 12-week study. Mirabegron treatment improved the IIEF-5 scores in five patients (38.4%) by 4 points or more, whereas IIEF-5 scores were not affected by Mirabegron treatment in eight patients (61.5%). There were no clinically relevant decreases in the IIEF-5 score. Significant improvements were observed in intercourse satisfaction at week eight compared to baseline (p = 0.01). Orgasmic function and sexual desire were not affected by Mirabegron treatment. As expected, Mirabegron treatment reduced OAB symptoms based on OAB-q short form (p = 0.006) and OAB-q total health-related quality of life (HRQL) scores compared to baseline (p = 0.03). Residual bladder volumes were not affected by treatment. No serious side effects were reported during the study period. This study suggests that Mirabegron may improve both EF and OAB-related symptoms in some individuals without causing serious adverse events.

Oral Pharmacologic Management of Overactive Bladder Syndrome: Where Do We Stand?

Overactive bladder syndrome (OAB) is a prevalent disorder with a significant impact on quality of life. Despite this high prevalence, there is significant underdiagnosis and undertreatment due to several barriers, including embarrassment, poor communication and low patient adherence. Currently, various antimuscarinic are available in the treatment of OAB. The introduction of mirabegron has broadened the therapeutic approach and combination therapy of both agents can be valuable in clinical practice. Yet, patient adherence to most drugs for OAB is still relatively poor. Healthcare providers need to identify and utilise strategies to improve treatment adherence by defining clear treatment goals, implement educational methods and frequently communicate with patients to identify problems with adherence. The elderly population form need special attention as in these patients, anticholinergics should be prescribed with care and adequate knowledge regarding pharmacokinetics and drug interactions in essential. Furthermore, patient expectations should be clearly discussed. In this narrative review, the current advances in oral pharmacotherapy are evaluated and the most important factors involved in the management of OAB are discussed.

Is mirabegron equally as effective when used as first- or second-line therapy in women with overactive bladder?

INTRODUCTION AND HYPOTHESIS

No previous studies have investigated the efficacy of mirabegron 50 mg as the first-line therapy in OAB patients. Hence, the primary objective of this study was to evaluate the efficacy of mirabegron in treatment-naive patients in comparison with those who had discontinued antimuscarinic therapy because of insufficient efficacy.

METHODS

All consecutive women who had pure OAB symptoms (including urgency with or without urgency incontinence and frequency) for at least 3 months were considered for this study. Women were divided into two groups: women without any previous pharmacological treatment for OAB (group 1) and women with a previous history of failed antimuscarinics therapy (group 2).

RESULTS

At 3-month follow-up, the objective results on the basis of the frequency-volume chart showed a significant improvement in both groups. Furthermore, a significant reduction in the Overactive Bladder Questionnaire Short Form (OABq-SF) score and in the Indevus Urgency Severity Scale (IUSS) questionnaire were reported in both groups. However, the improvement in objective and subjective outcomes was superior in group 1 to that in group 2.

CONCLUSIONS

Mirabegron is efficacious in improving OAB symptoms in both naïve patients and those who discontinued primary antimuscarinic therapy; however, its efficacy is superior when prescribed as first-line therapy.

The efficacy and tolerability of mirabegron, a β3 adrenoceptor agonist, in patients with symptoms of overactive bladder

Mirabegron, is the only β-3 adrenoreceptor (AR) agonist available for the treatment of overactive bladder (OAB). To assess the efficacy and tolerability of this novel drug therapy, two phase II and six phase III Astellas-sponsored trials have been conducted with over 10,500 adults with OAB recruited. Of these, seven were randomized, double blind, 12-week placebo controlled studies and the other was for 12 months and not placebo controlled. The evidence described would suggest that mirabegron is as efficacious as most antimuscarinics, including tolterodine extended release (ER) 4 mg, compared with placebo with regard to objective measures such as reduction in number of voids per 24 hours, mean volume per void, mean number of episodes of general urinary incontinence, urgency urinary incontinence and urgency per 24 hours; and subjective measures such as severity of urgency, patient perception of bladder condition and validated continence quality of life questionnaires. Regarding tolerability, these data would suggest that patients taking mirabegron suffer a similar rate of adverse effects as those taking placebo alone, whereas the rate in those taking antimuscarinics is greater. Thus mirabegron presents a safe and effective alternative treatment to antimuscarinics for patients with OAB symptoms. Patients who may particularly benefit from mirabegron include those who are unsuitable for antimuscarinics or who have previously struggled with antimuscarinic side effects.