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

Potential of Mirabegron and its Extended-release Formulations for the Treatment of Overactive Bladder Syndrome

BACKGROUND

Overactive bladder syndrome is a broadly occurring urological disorder with a distressing impact on the quality of life. The commonly used antimuscarinic drugs show poor patient compliance because of unsatisfactory potency, tolerability and high occurrence of adverse effects such as dry mouth, blurred vision, constipation, dizziness etc. Mirabegron is the first approved β3-adrenoreceptor agonist, used as mono or in combination therapies for overactive bladder syndrome.

OBJECTIVE

The present review provides an insight into the mechanism, pharmacokinetics, toxicokinetics, clinical trials and the development of various conventional and modified-release dosage forms of mirabegron for the treatment of overactive bladder syndrome.

RESULTS

The clinical trials of phase II and phase III of mirabegron demonstrated symptomatic relief from the overactive bladder without disturbing the micturition cycle. To date, mirabegron showed promising results for safety, tolerability and efficacy in patients with overactive bladder syndrome. The modified-release tablet dosage form of mirabegron appear to be a proficient and suitable replacement for antimuscarinics and revealed the tremendous potential to overcome the adverse effects of conventional antimuscarinic drugs like Oxybutyline chloride ER, Detrol LA, VESIcare, etc. Conclusion: Mirabegron shows a distinct mode of action, i.e., targeting β3-adrenoreceptors and improving bladder storage without altering void contractions. The limited side effects, high safety, efficacy and tolerability of mirabegron present an adequate substitute to antimuscarinics. However, long-term analysis and clinical studies are prerequisites for assessing the safety, tolerability and efficacy profile of mirabegron.

Efficacy and safety of mirabegron for the treatment of neurogenic detrusor overactivity resulting from traumatic spinal cord injury: A prospective study

OBJECTIVE

To assess the clinical, urodynamic efficacy, and safety of mirabegron in patients with neurogenic detrusor overactivity (NDO) consequent to traumatic spinal cord injury (SCI).

METHODS

This prospective cohort study was performed between January 2018 and July 2019 and included adult patients with stable traumatic suprasacral SCI, performing clean intermittent catheterization (CIC), and demonstrating NDO on urodynamic study (UDS). A 3-day bladder diary was made at the baseline after which all patients were started on Mirabegron 50 mg. They were followed up at 6 weeks with a repeat bladder diary and UDS which were compared with those at the baseline.

RESULTS

A total of 30 patients (4 females, 26 males, mean age: 30.07 years) were included. After 6 weeks of treatment, 5 out of the 29 incontinent patients became completely dry. The mean frequency of CIC decreased from 6.63 at the baseline to 5.37 at 6 weeks (p = .002), the mean CIC volume increased from 275 ml to 341 ml (p = .0002), the mean number of incontinence episodes in between CIC reduced from 3.97 to 2.27 (p < .0001) and time from CIC to leakage increased from 1.73 h to 2.75 h (p < .0001). The mean cystometric capacity increased from 348 ml to 406 ml (p = .008) and the maximum amplitude of NDO decreased from 54 cm H₂ O to 41 cm H₂ O (p = .005) at 6 weeks. Only two patients reported new onset dry mouth. No major adverse events were noted and none discontinued treatment.

CONCLUSION

Mirabegron is efficacious and safe in patients with NDO consequent to traumatic SCI.

Is coexistent overactive-underactive bladder (with or without detrusor overactivity and underactivity) a real clinical syndrome? ICI-RS 2019

AIMS

Lower urinary tract symptoms (LUTS) can be classified into symptom syndromes based on which symptoms are predominant. Overactive bladder (OAB) syndrome, a storage dysfunction, and underactive bladder (UAB) syndrome, a voiding dysfunction, are common syndromes, which urodynamic tests may show to be caused by detrusor overactivity (DO) and detrusor underactivity (DU), but can also be associated with other urethro-vesical dysfunctions. Sometimes OAB and UAB can coexist in the same patient and, if so, need a specific approach beyond treatment of the single and apparently opposing syndromes.

METHODS

During its 2019 meeting in Bristol, the International Consultation on Incontinence Research Society held a literature review and expert consensus discussion focused on the emerging awareness of the coexisting overactive-underactive bladder (COUB).

RESULTS

The consensus considered whether COUB is the combination of OAB and UAB syndromes, or a real unique clinical syndrome in the same patient, possibly with a common etiology. Definitions, pathophysiology, diagnosis, and treatment were discussed, and high-priority research questions were identified.

CONCLUSIONS

COUB (with or without urodynamic evidence of DO and DU) may be considered a real clinical syndrome, because it differs from single OAB and UAB, and may not be the combination of both syndromes. Urodynamic tests may be necessary in unclear cases or in cases not responding to initial treatment of the most troublesome symptoms. It is pivotal to define the evolution of the syndrome and the characteristic population, and to recognize predictive or phenotyping factors to develop a specific approach and adequate outcome measures.

Meta-analysis of the efficacy and safety of mirabegron and solifenacin monotherapy for overactive bladder

AIM

We conducted a meta-analysis to evaluate the safety and efficacy of mirabegron (50 mg) and solifenacin (5 mg) monotherapy for overactive bladder (OAB) during a 12-week cycle.

METHODS

Randomized controlled trials (RCTs) of mirabegron and solifenacin for OAB were searched systematically by using MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. The reference lists of retrieved studies were also perused.

RESULTS

Five RCTs which compared solifenacin with mirabegron were studied. Mirabegron achieved the same effect as solifenacin in treating OAB. The mean number of incontinence episodes per 24 h (P = 0.20), mean number of micturitions per 24 h (P = 0.11), mean number of urgency episodes per 24 h (P = 0.23), and mean volume voided per micturition (P = 0.05) suggested that mirabegron and solifenacin had no significant differences in terms of OAB treatment. With regard to drug-related treatment-emergent adverse events (DR-TEAEs) and dry mouth, mirabegron showed better tolerance than solifenacin. Post-voiding residual volume showed a distinct difference in the two groups. Hypertension and tachycardia did not show a significant difference between the two groups, but the pulse rate did.

CONCLUSION

The therapeutic effect of mirabegron is similar to that of solifenacin, and mirabegron does not increase the risk of adverse events (AEs).

Overactive Bladder is a Distress Symptom in Heart Failure

The prevalence of Heart failure (HF) is expected to increase worldwide with the aging population trend. The numerous symptoms of and repeated hospitalizations for HF negatively affect the patient’s quality of life and increase the patient’s economic burden. Up to 50% of patients with HF suffer from urinary incontinence (UI) and an overactive bladder (OAB). However, there are limited data about the relationship between UI, OAB, and HF. The association between HF and urinary symptoms may be directly attributable to worsening HF pathophysiology. A comprehensive literature review was conducted for all publications between January 2000 and November 2017 using the PubMed, Embase, and Cochrane databases. HF represents a major and growing public health problem, with an increased risk of UI and an OAB as comorbidities. Possible effects of HF on urinary problems may be mediated by the prescription of medications for symptomatic relief. Although diuretics are typically used to relieve congestion, and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers improve survival, these classes of drugs have been suggested to worsen urinary symptoms in the presence of HF. Further research is required to understand the impact of UI and an OAB on the HF illness trajectory.

Efficacy and safety of mirabegron, a β3 -adrenoceptor agonist, in patients with detrusor hyperactivity and impaired contractility

OBJECTIVE

We examined the efficacy and safety of mirabegron in elderly patients with urodynamic detrusor hyperactivity with impaired contractility (DHIC).

METHODS

Patients diagnosed with DHIC received daily dose of mirabegron (25mg). Subjective symptom scores, uroflowmetry data, and adverse events (AEs) were recorded for all patients at baseline and after 1, 3, and 6 months treatment. Comparisons were made for each patient individually and between patients with detrusor overactivity (DO).

RESULTS

Of the 65 patients enrolled in the study, 25 had DHIC and 40 had DO (mean [± SD] age 79.3 ± 9.6 and 75.6 ± 10.7 years, respectively). At the 6-month follow-up, significant (P < .05) improvement was seen compared with baseline in both the DHIC and DO groups in terms of OAB symptom scores (4.72 ± 3.05 vs. 6.88 ± 4.06 and 4.50 ± 2.99 vs. 6.70 ± 3.60, respectively), urgency severity score (1.90 ± 2.00 vs. 3.35 ± 1.13 and 1.58 ± 1.93 vs. 3.00 ± 1.65, respectively), and global response assessment (1.80 ± 1.41 and 1.73 ± 1.34, respectively). In the DHIC group, post-void residual (PVR) volume decreased from 153 ± 52.7 mL at baseline to 85.8 ± 90.1 mL at 6th month (P < .05) and voiding efficiency improved from 40.0 ± 20.7% to 62.6 ± 28.3% (P < .05). Common AEs included dry mouth and dizziness, yet 16% of DHIC patients developed PVR >180 mL.

CONCLUSION

Mirabegron was an effective treatment option in elderly patients with urodynamic DO and DHIC in the present study. The AEs reported were mild and infrequent.

Evaluating the efficacy and tolerability of mirabegron, a β3-adrenoceptor agonist, for the treatment of overactive bladder: Systematic review and network meta-analysis

Purpose:

Overactive bladder (OAB) is a common condition affecting approximately 11% of individuals worldwide. One of the newest treatment options for OAB symptoms is mirabegron. The objective of this network meta-analysis is to evaluate the extent of the efficacy and tolerability of mirabegron compared both to placebo and first-line anticholinergic pharmacotherapies.

Methods:

Articles were identified through the MEDLINE, EMBASE, and Cochrane databases using the search term ‘mirabegron’. All original, prospective, randomised, controlled, double-blind clinical trials studying mirabegron in adults receiving initial treatment for OAB were included. Efficacy was assessed based on outcome variables and responder data. Tolerability was evaluated for reported adverse events.

Results:

Thirteen studies including a total of 13,333 individuals were included. Mirabegron demonstrated better efficacy compared to placebo and tolterodine extended release 4 mg. Compared to placebo, the incidence of tachycardia and nasopharyngitis was greater with mirabegron 50 mg, and the incidence of cardiac arrhythmia was greater in 100 mg treatment groups. Mirabegron 100 mg also demonstrated a lower incidence of cardiac arrhythmia compared to tolterodine.

Conclusions:

The current study presents new information that may affect patient-centred strategies for the management of OAB, with a particular concern for cardiovascular safety.

[Not Available]

Zusammenfassung. OAB (overactive bladder syndrome) ist zwar ein häufiges Leiden, doch wird es oft nicht diagnostiziert und deshalb nicht behandelt. Die Behandlung erfolgt symptomatisch. Im Praxisalltag muss vorgängig eine Basis-(Ausschluss)-Diagnostik durchgeführt werden. Das Führen eines Blasentagebuchs ist sowohl für die Diagnostik als auch für den Verlauf wichtig. Eine urogynäkologische Abklärung mit Urodynamik empfiehlt sich in unklaren Situationen und beim Vorliegen einer gemischten Symptomatik mit Symptomen einer Belastungsinkontinenz oder bei gleichzeitigem Vorliegen einer Blasenentleerungsstörung. Die Therapie erfolgt Schritt für Schritt. Schon einfache Verhaltensänderungen und ein Blasen- und Beckenbodentraining können die Symptomatik deutlich verbessern. Viele Patientinnen profitieren aber zusätzlich von der medikamentösen Therapie. Jahrzehntelang standen dazu alleinig Anticholinergika zur Verfügung. Doch die Langzeitcompliance ist unter diesen Medikamenten gering. Neu erweitern β3-Adrenorezeptor-Agonisten das therapeutische Spektrum: Bei ähnlicher Wirkung unterscheidet sich das Nebenwirkungsprofil unter anderem durch das Fehlen von Mundtrockenheit. Bei therapierefraktärer OAB steht die intravesikale Injektion von Onabotulinumtoxin A als sehr effektive Therapie zur Verfügung. In seltenen Fällen ist auch eine Neuromodulation indiziert.

Benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH), which causes lower urinary tract symptoms (LUTS), is a common diagnosis among the ageing male population with increasing prevalence. Many risks factors, both modifiable and non-modifiable, can increase the risk of development and progression of BPH and LUTS. The symptoms can be obstructive (resulting in urinary hesitancy, weak stream, straining or prolonged voiding) or irritative (resulting in increased urinary frequency and urgency, nocturia, urge incontinence and reduced voiding volumes), or can affect the patient after micturition (for example, postvoid dribble or incomplete emptying). BPH occurs when both stromal and epithelial cells of the prostate in the transitional zone proliferate by processes that are thought to be influenced by inflammation and sex hormones, causing prostate enlargement. Patients with LUTS undergo several key diagnostic investigations before being diagnosed with BPH. Treatment options for men with BPH start at watchful waiting and progress through medical to surgical interventions. For the majority of patients, the starting point on the treatment pathway will be dictated by their symptoms and degree of bother.