Mirabegron: a Beta-3 agonist for overactive bladder

Effect of Mirabegron in Men With Overactive Bladder and Erectile Dysfunction: A Prospective Observational Study

BACKGROUND

As it has been observed that the erect penis has been the epitome of virility for the male community for decades, it became necessary to search for alternative treatments for the cause. So, the study was performed to evaluate the potential impact of mirabegron in men with mild to moderate erectile dysfunction (ED) and overactive bladder (OAB).

METHODS

It was a prospective, observational study that was carried out at the Department of Urology at Rajendra Institute of Medical Sciences, Ranchi, for a duration of two years and included a total of two hundred fifty patients. The individuals included had a diagnosis of mild to moderate erectile dysfunction (ED) along with symptoms of OAB. The overactive bladder questionnaire (OAB-q) score and the International Index of Erectile Dysfunction-5 (IIEF-5) score were used, respectively, to measure the impact of mirabegron on ED and OAB. Then, the changes in ED and OAB were evaluated at two, four, eight, and 12 weeks.

RESULTS

Among the total 250 patients recruited, around 32.5% of them had mild ED, 17.5% were diagnosed with mild to moderate ED, and 50% suffered from moderate ED. The IIEF-5 scores improved by four points or more in 86.25%, 91.25%, and 71.25% of patients after four, eight, and 12 weeks, respectively. OAB-q scores were likewise shown to decline in the fourth (13.1 ± 4.3) and eighth (12.8 ± 4.2) weeks when compared to the baseline (17.4 ± 5.5). Also, adverse events reported did not hamper the progress of the study.

CONCLUSION

The study concluded that mirabegron has a beneficial impact on controlling OAB symptoms among men diagnosed with mild to moderate ED. The effects last for only eight weeks, and then they decline. Furthermore, mirabegron was well-tolerated among patients and had no safety concerns with its use.

Therapeutic Potential for Beta-3 Adrenoreceptor Agonists in Peripheral Arterial Disease and Diabetic Foot Ulcers

Annually, peripheral arterial disease is estimated to cost over USD 21 billion and diabetic foot disease an estimated at USD 9-13 billion. Mirabegron is a TGA-approved beta-3 adrenoreceptor agonist, shown to be safe and effective in the treatment of overactive bladder syndrome by stimulating bladder smooth muscle relaxation. In this review, we discuss the potential use of beta-3 adrenoreceptor agonists as therapeutic agents repurposed for peripheral arterial disease and diabetic foot ulcers. The development of both conditions is underpinned by the upregulation of oxidative stress pathways and consequential inflammation and hypoxia. In oxidative stress, there is an imbalance of reactive oxygen species and nitric oxide. Endothelial nitric oxide synthase becomes uncoupled in disease states, producing superoxide and worsening oxidative stress. Agonist stimulation of the beta-3 adrenoreceptor recouples and activates endothelial nitric oxide synthase, increasing the production of nitric oxide. This reduces circulating reactive oxygen species, thus decreasing redox modification and dysregulation of cellular proteins, causing downstream smooth muscle relaxation, improved endothelial function and increased angiogenesis. These mechanisms lead to endothelial repair in peripheral arterial disease and an enhanced perfusion in hypoxic tissue, which will likely improve the healing of chronic ulcers.

A Comparative Study of Solifenacin, Mirabegron, and Their Combination as Bladder Relaxants in the Management of Overactive Bladder

Introduction  Overactive bladder (OAB) is a medical state that presents as the urgency of urine and increased frequency of micturition and is diagnosed on the basis of the presence of these symptoms in the absence of other explainable diagnoses. The management of this condition includes conservative management, medical management/pharmacotherapy, and surgical management. The overactive bladder has been treated with smooth muscle relaxants, but there are conflicting results. Hence, this study aimed to assess the result of the two smooth muscle relaxants, mirabegron and solifenacin, and their combination to manage an overactive bladder. Methodology  A clinical trial was conducted at Swaroop Rani Nehru Hospital, Motilal Nehru Medical College, Prayagraj, India, over the period from November 2019 to December 2020. Ninety patients with OAB were divided into three groups: G1, G2, and G3. These groups were administered solifenacin, mirabegron, and a combination of mirabegron and solifenacin (S+M), respectively. Follow-ups were conducted at 2, 4, 12, and 18 weeks for evaluation. Data were entered into IBM SPSS Statistics for Windows, Version 23 (Released 2015; IBM Corp., Armonk, New York, United States). Appropriate statistical tests, including the chi-square and ANOVA, were employed in this study. Observation  The combination of mirabegron and solifenacin was significantly more effective in terms of response compared to solifenacin alone. There was no significant difference between solifenacin versus mirabegron, or between mirabegron (M) and the combination of mirabegron (M) and solifenacin (S). Side effects were more severe in patients taking high doses of solifenacin. Conclusion  The S + M combination has higher efficacy than solifenacin and mirabegron when given alone.

Vibegron 50 mg Once Daily Improves OABSS, OAB-q SF Score in OAB Patients ≥80 Years Old in Real-World Clinical Settings and Switching from Other OAB Drugs May Reduce Residual Urine Volume

Objective

The treatment effects of vibegron have not previously been evaluated in a prospective, non-interventional observational study of elderly Japanese patients, particularly those ≥80 years old. In addition, no reports have referred to residual urine volume in switching cases. We therefore grouped patients by condition and investigated the treatment effects of vibegron on Overactive Bladder Symptom Score (OABSS), Overactive Bladder Questionnaire Short Form (OAB-q SF), and residual urine volume in each group.

Methods

This multicenter, prospective, non-interventional, observational study consecutively enrolled OAB patients with total OABSS score ≥3 and OABSS question 3 score ≥2. Sixty-three patients from six centers were recruited. Vibegron 50 mg once daily was administered for 12 weeks as first-line monotherapy (first-line group), monotherapy switching from antimuscarinics or mirabegron due to failure of prior therapy (no washout period), or combination therapy with antimuscarinics (second-line group). OABSS, OAB-q SF, and residual urine volume were collected after 4 and 12 weeks. Adverse events were also recorded at each visit.

Results

Of the 63 patients registered, 61 were eligible for analysis (first line, n=36; second line, n=25). The OABSS, excluding daytime frequency scores, and OAB-q SF scale showed significant improvement in all conditions. Switching from mirabegron to vibegron significantly reduced residual urine volume. No serious treatment-related adverse events were encountered.

Conclusion

Vibegron 50 mg once daily significantly improved OABSS and OAB-q SF even in patients ≥80 years old. Notably, switching from mirabegron to vibegron resulted in significant improvements to residual urine volume.

Adverse events related to antimuscarinics and beta-3-agonist: "real-life" data from the Eudra-Vigilance Database

BACKGROUND

Antimuscarinic (AM) and beta-3-agonist (B3A) treatment are the standard first-line pharmacological treatment used to manage overactive bladder (OAB) patients. Aim of our study was to analyze real-life data of adverse events related to AMs and B3A reported on Eudra-Vigilance (EV) Database.

METHODS

EV database is the system for managing and analyzing information on suspected adverse reactions to medicines which have been authorized or being studied in clinical trials in the European Economic Area (EEA). We recorded the number of AEs for antimuscarinic and beta-3-agonist per category and severity until January 2021.

RESULTS

Overall, 2313 AEs were reported for oxybutinin, 5129 for solifenacin, 2483 for tolterodine, 3523 for fesoterodine, 787 for trospium, 621 for propiverine and 7213 for mirabegron. Urinary retention was higher for fesoterodine (43%) and tolterodine (23%) when compared to solifenacin (10%), mirabegron (11%) and oxybutinin (4%). Cognitive disorder was uncommon for all the analyzed drugs analyzed. Regarding anticolinergic AEs: vision blurred, dry mouth and constipation were higher for AMs when compared to mirabegron. Their prevalence was higher in female patients. Mirabegron presented a higher risk of hypertension (7%) when compared to oxybutinin (2%, P<0.01), solifenacin (2%, P<0.01), tolterodine (2%, P<0.01) and fesoterodine (1%, P<0.01); the rate of hypertension was higher in females (63%) than males (29%) (P<0.01). The risk of acute urinary retention was also significantly higher (15% vs. 10%, P<0.01) in older patients (>85 years).

CONCLUSIONS

Real life data is consistent with registry studies regarding the rate of AEs related to antimuscarinic and beta-3-agonist. However some differences were observed. Female patients present higher rates of AEs when compared to male patients. The risk of acute urinary retention was particularly evident in the octogenarians.

Adipokines: Deciphering the cardiovascular signature of adipose tissue

Obesity and hypertension are intimately linked due to the various ways that the important cell types such as vascular smooth muscle cells (VSMC), endothelial cells (EC), immune cells, and adipocytes, communicate with one another to contribute to these two pathologies. Adipose tissue is a very dynamic organ comprised primarily of adipocytes, which are well known for their role in energy storage. More recently adipose tissue has been recognized as the largest endocrine organ because of its ability to produce a vast number of signaling molecules called adipokines. These signaling molecules stimulate specific types of cells or tissues with many adipokines acting as indicators of adipocyte healthy function, such as adiponectin, omentin, and FGF21, which show anti-inflammatory or cardioprotective effects, acting as regulators of healthy physiological function. Others, like visfatin, chemerin, resistin, and leptin are often altered during pathophysiological circumstances like obesity and lipodystrophy, demonstrating negative cardiovascular outcomes when produced in excess. This review aims to explore the role of adipocytes and their derived products as well as the impacts of these adipokines on blood pressure regulation and cardiovascular homeostasis.

The novel anti-colitic effect of β-adrenergic receptors via modulation of PS1/BACE-1/Aβ axis and NOTCH signaling in an ulcerative colitis model

Although dysautonomia was documented in inflammatory bowel disease, with activation of the stress-related sympathetic system, the role of agonists/antagonists of the adrenergic receptors is not conclusive. Moreover, ulcerative colitis was recently linked to dementia, but the potential role of the presenilin 1(PS1)/BACE-1/beta-amyloid (Aβ) axis has not been evaluated. Hence, we investigated the impact of mirabegron (β3-agonist) and/or carvedilol (β1/β2 antagonist) on iodoacetamide-induced ulcerative colitis with emphasis on the novel pathomechanism of the PS1/BACE-1/Aβ axis in ulcerative colitis, and its relation to the inflammatory cascade, fibrotic processes, and the gut barrier dysfunction. Ulcerated rats were either left untreated or treated for 8 days with mirabegron and/or carvedilol. Besides minimizing colon edema and weight loss, and improving colon structure, mirabegron and/or carvedilol abated colonic PS1/BACE-1/Aβ axis and the NOTCH1/NICD/HES1 hub besides the inflammatory cascade GSK3-β/NF-κΒ/TNF-α, and the oxidative stress marker malondialdehyde. The anti-fibrotic effect was verified by boosting SMAD-7 and inhibiting TGF-β1, α-SMA immunoexpression, and MTC staining. Moreover, the drugs improved the gut barrier function, attested by the increased goblet cells and expression of E-cadherin, and the inhibited expression of p (Y654)-β-catenin to preserve the E-cadherin/β-catenin adherens junction (AJ). These signaling pathways may be orchestrated by the replenished PPAR-γ, a transcription factor known for its anti-colitic effect. Conclusion: Besides maintaining the gut barrier, mirabegron and/or carvedilol mediated their anti-colitic effect by their anti-oxidant, anti-inflammatory, and anti-fibrotic capacities. The therapeutic effect of these drugs depends partly on suppressing the harmful signaling pathways PS1/BACE-1/Aβ, NOTCH1/NICD/HES1, GSK3-β/NF-κΒ/TNF-α, and TGF-1β/α-SMA while enhancing PPAR-γ, SMAD-7, mucus, and AJ.

The translational implications of the science behind the overactive bladder and the role of OnabotulinumtoxinA

Urinary incontinence (UI) is a very common condition that can affect patients of all ages and the commonest cause is an overactive bladder (OAB). Most patients with OAB were treated with pharmacotherapy and major surgery. Over 25 years ago, Dasgupta, Fowler et al. studied the presence and role of C fibres in the human bladder which are highly sensitive to capsaicin, the active ingredient of chillies. When capsaicin was instilled into patients' bladders as a synthetic solution, it was found to be highly effective in some patients. Capsaicin was later replaced by Resiniferatoxin. Both toxins desensitised C-fibres through the capsaicin receptor, TRPV1, without any lasting damage to the bladder itself. The discovery of botulinum toxin and its use in the treatment of OAB represents a major breakthrough, in the treatment of OAB. Another key innovation was the development of technique to administer the drug under local anaesthesia which allowed numerous patients to benefit from treatment who would otherwise have been precluded because of the need for injection under general anaesthetic. After extensive trials over many years Botox (OnabotulinumtoxinA) is now licensed for use in OAB. Compared to other treatments for overactive bladder, OnabotulinumtoxinA is more cost-effective and less invasive. It is thought to have changed the quality of life of an estimated 5 million patients worldwide.

β3 Relaxant Effect in Human Bladder Involves Cystathionine γ-Lyase-Derived Urothelial Hydrogen Sulfide

It is now well established that the urothelium does not act as a passive barrier but contributes to bladder homeostasis by releasing several signaling molecules in response to physiological and chemical stimuli. Here, we investigated the potential contribution of the hydrogen sulfide (H2S) pathway in regulating human urothelium function in β3 adrenoceptor-mediated relaxation. The relaxant effect of BRL 37344 (0.1–300 µM), a selective β3 adrenoceptor agonist, was evaluated in isolated human bladder strips in the presence or absence of the urothelium. The relaxant effect of BRL 37344 was significantly reduced by urothelium removal. The inhibition of cystathionine-γ-lyase (CSE), but not cystathionine-β-synthase (CBS), significantly reduced the BRL 37344 relaxing effect to the same extent as that given by urothelium removal, suggesting a role for CSE-derived H2S. β3 adrenoceptor stimulation in the human urothelium or in T24 urothelial cells markedly increased H2S and cAMP levels that were reverted by a blockade of CSE and β3 adrenoceptor antagonism. These findings demonstrate a key role for urothelium CSE-derived H2S in the β3 effect on the human bladder through the modulation of cAMP levels. Therefore, the study establishes the relevance of urothelial β3 adrenoceptors in the regulation of bladder tone, supporting the use of β3 agonists in patients affected by an overactive bladder.

The Regulation of Adipose Tissue Health by Estrogens

Obesity and its' associated metabolic diseases such as type 2 diabetes and cardiometabolic disorders are significant health problems confronting many countries. A major driver for developing obesity and metabolic dysfunction is the uncontrolled expansion of white adipose tissue (WAT). Specifically, the pathophysiological expansion of visceral WAT is often associated with metabolic dysfunction due to changes in adipokine secretion profiles, reduced vascularization, increased fibrosis, and enrichment of pro-inflammatory immune cells. A critical determinate of body fat distribution and WAT health is the sex steroid estrogen. The bioavailability of estrogen appears to favor metabolically healthy subcutaneous fat over visceral fat growth while protecting against changes in metabolic dysfunction. Our review will focus on the role of estrogen on body fat partitioning, WAT homeostasis, adipogenesis, adipocyte progenitor cell (APC) function, and thermogenesis to control WAT health and systemic metabolism.

Urodynamic effect of vibegron on neurogenic lower urinary tract dysfunction in individuals with spinal cord injury: A retrospective study

STUDY DESIGN

A Retrospective study.

OBJECTIVES

To investigate the effects of vibegron on urodynamic parameters of individuals with spinal cord injury (SCI).

SETTING

The National Hospital Organization, Murayama Medical Center, Japan.

METHODS

We retrospectively analyzed the urodynamic parameters of 31 individuals with SCI within one year after injury, who were diagnosed with neurogenic lower urinary tract dysfunction (NLUTD) according to a urodynamic study (UDS), and prescribed vibegron between December 2018 and December 2020. Treatment criteria were as follows: cystometric capacity of <200 mL, bladder compliance of <20 mL/cmH₂O, and/or presence of detrusor overactivity in the first UDS. We compared urodynamic data before and after vibegron treatment.

RESULTS

Vibegron administration increased the maximum cystometric capacity (MCC) (median, from 185.0 to 340.0 mL, P = 0.001), bladder compliance (median, from 8.3 to 20.0 mL/cmH₂O, P < 0.001).

CONCLUSION

Vibegron therapy improved the bladder capacity and bladder compliance of individuals with NLUTD and SCI.

Beta 3 Adrenoreceptor Agonist for the Management of Lower Urinary Tract Symptoms in Men With Benign Prostatic Hyperplasia: A Systematic Review

Beta-3 adrenoceptor (B3AR) agonist which mediate detrusor relaxation has been tried as a new treatment modality for men with benign prostatic hyperplasia (BPH). However, it remains unclear whether the B3AR agonist has more clinical benefits and fewer adverse effects in men with BPH than in women. We performed a comprehensive search using multiple databases, trials registries, other sources of grey literature, and conference proceedings regardless of language or publication status and included randomized controlled trials. Two review authors independently screened the literature, extracted data, and assessed risk of bias. We performed statistical analyses using a random-effects model and interpreted them according to the Cochrane Handbook for Systematic Reviews of Interventions. Primary outcomes were urologic symptom scores, quality of life (QoL), and overall adverse events. We found 4 randomized controlled trials with 1,105 participants in 3 comparisons. All studies reported short-term outcomes (ranged from 8 weeks to 12 weeks). Mirabegron, tamsulosin, silodosin, fesoterodine, and tadalafil were administrated as intervention. While B3AR agonist can improve the patient-important outcomes within group (before and after treatment), B3AR agonist combination therapy with current standard BPH treatment such as alpha blocker or anticholinergic may not have additional effects on urological symptom scores and QoL compared to alpha blocker or anticholinergic monotherapy. B3AR agonist therapy with phosphodiesterase 5 inhibitor (PDE5I) showed statistical improvement on urological symptom scores or QoL compared to PDE5I monotherapy. For safety profile, B3AR agonist in all 3 comparisons may not increase adverse event rate. While B3AR agonists may be used for the treatment of lower urinary tract symptoms in men with BPH if storage symptoms with standard BPH treatment are insufficient, B3AR agonists appear to have trivial or similar effects compared to current standard BPH treatment.

Role of α- and β-adrenergic signaling in phenotypic targeting: significance in benign and malignant urologic disease

The urinary tract is highly innervated by autonomic nerves which are essential in urinary tract development, the production of growth factors, and the control of homeostasis. These neural signals may become dysregulated in several genitourinary (GU) disease states, both benign and malignant. Accordingly, the autonomic nervous system is a therapeutic target for several genitourinary pathologies including cancer, voiding dysfunction, and obstructing nephrolithiasis. Adrenergic receptors (adrenoceptors) are G-Protein coupled-receptors that are distributed throughout the body. The major function of α1-adrenoceptors is signaling smooth muscle contractions through GPCR and intracellular calcium influx. Pharmacologic intervention of α-and β-adrenoceptors is routinely and successfully implemented in the treatment of benign urologic illnesses, through the use of α-adrenoceptor antagonists. Furthermore, cell-based evidence recently established the antitumor effect of α1-adrenoceptor antagonists in prostate, bladder and renal tumors by reducing neovascularity and impairing growth within the tumor microenvironment via regulation of the phenotypic epithelial-mesenchymal transition (EMT). There has been a significant focus on repurposing the routinely used, Food and Drug Administration-approved α1-adrenoceptor antagonists to inhibit GU tumor growth and angiogenesis in patients with advanced prostate, bladder, and renal cancer. In this review we discuss the current evidence on (a) the signaling events of the autonomic nervous system mediated by its cognate α- and β-adrenoceptors in regulating the phenotypic landscape (EMT) of genitourinary organs; and (b) the therapeutic significance of targeting this signaling pathway in benign and malignant urologic disease. Video abstract.

Efficacy of vibegron, a novel β3-adrenoreceptor agonist, for lower urinary tract dysfunction in mice with spinal cord injury

OBJECTIVES

To investigate the effect of vibegron, a new clinically approved β3-adrenoceptor agonist in lower urinary tract dysfunction in mice with spinal cord injury.

METHODS

Investigators performed cystometry under awake conditions in 4-week spinal cord injury female mice. Two weeks after spinal cord injury, saline or vibegron (30 mg/kg) was orally administered for 2 weeks prior to the urodynamic study. Investigators removed L6-S1 dorsal root ganglia from the saline- or vibegron-treated spinal cord injury mice as well as from saline-treated normal (spinal intact) mice to evaluate the levels of transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, activating transcription factor 3, and inducible nitric oxide synthase transcripts using real-time polymerase chain reaction.

RESULTS

In vibegron-treated spinal cord injury mice, nonvoiding contractions during bladder filling, which were increased in spinal cord injury compared to spinal intact mice, were significantly decreased. Micturition pressure or voiding efficiency was not significantly increased in comparison to measurements in saline-treated spinal cord injury mice. The expression of transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, activating transcription factor 3, and inducible nitric oxide synthase messenger RNA was increased in spinal cord injury mice compared to spinal intact mice, but significantly decreased after vibegron treatment.

CONCLUSIONS

Vibegron improves spinal cord injury-induced detrusor overactivity in addition to significantly reducing C-fiber afferent receptors such as transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, and inflammatory cytokines/markers, such as activating transcription factor 3 and inducible nitric oxide synthase, in spinal cord injury mice. Thus, vibegron might be effective in the treatment of storage lower urinary tract dysfunction induced by C-fiber afferent activation after spinal cord injury.

Efficacy and Safety of Vibegron Add-on Therapy in Men With Persistent Storage Symptoms After Receiving Alpha 1-Blocker or Phosphodiesterase 5 Inhibitor: A Preliminary Study

OBJECTIVE

To investigate the efficacy and safety of vibegron add-on therapy in men with persistent storage symptoms receiving α-1 blockers or PDE5 inhibitor for benign prostatic hyperplasia and then determine the independent factors affecting the efficacy of vibegron.

METHODS

Vibegron 50 mg was administered for 12 weeks to 42 patients (72.0 ± 8.2 years) with persistent storage symptoms who had taken α-1 blockers (22 patients) or PDE5 inhibitor (20 patients). The primary endpoint was change in the overactive Bladder (OAB) Symptom Score from baseline to end of treatment. The secondary endpoints were changes in each question of several questionnaires, maximum flow rate and residual urine volume. Finally, independent factors affecting the efficacy of vibegron were investigated.

RESULTS

Total OAB Symptom Score was significantly decreased (6.21 ± 3.12 vs 4.38 ± 2.46; P < .001). Although each score of several questionnaires, especially for storage symptoms, improved significantly, no significant improvement was found in stress incontinence, straining, bladder pain and urethral pain in the Core Lower Urinary Tract Symptom score. Maximum flow rate and residual urine volume did not change, and no patient discontinued vibegron because of adverse events. Multiple regression analysis showed that OAB Symptom Score, Core Lower Urinary Tract Symptom score, prostate volume and monotherapy with α-1 blocker were independent factors affecting the efficacy of vibegron.

CONCLUSION

Add-on therapy of vibegron to monotherapy with α-1 blockers or PDE5 inhibitor for patients with benign prostatic hyperplasia and persistent storage symptoms was effective and safe.

B3 agonists or anticholinergics in the treatment of the lower urinary tract dysfunction in patients with multiple sclerosis?-A randomized study

INTRODUCTION AND OBJECTIVE

Multiple sclerosis (MS) is the most frequent autoimmune demyelinating disease of the central nervous system. MS patients usually present with lower urinary tract dysfunction (LUTD). Objective of this study is to evaluate and compare the efficacy and safety of treating MS patients with LUTD with either a b3 agonist (mirabegron) or anticholinergics. The study's primary outcome is the LUTD symptom improvement.

MATERIAL AND METHODS

This is a multi-center, single-blinded, comparative study including 91 MS patients with LUTD. At baseline, patients underwent thorough clinical examination, urine cultivation and abdominal ultrasound and completed urination diaries and specific, validated questionnaires (NBSS, MusiQoL). At second visit, patients were administered either mirabegron or anticholinergics. Treatment was always carried out alongside with MS treatment. Reevaluation was performed 3 months after first visit. Patients underwent the same clinical and imaging tests that were carried out at first visit.

RESULTS

We compared several clinical and imaging parameters between the two groups at first visit and month 3 after treatment. Νo statistical difference was noted between the mirabegron group and the anticholinergic group in terms of LUTD improvement. In both groups, improvement from baseline regarding LUTD was recorded. Statistical analysis was performed using the paired and unpaired t test method. No patient discontinued either medication due to side effects.

CONCLUSIONS

MS patients receiving either mirabegron or anticholinergic therapy for LUTD showed improvement. Nevertheless, no statistical difference was noted between the two cohorts at 3 months in terms of drug efficacy in all the statistically significant parameters.

Evaluating vibegron for the treatment of overactive bladder

INTRODUCTION

Vibegron is a very selective new β3-adrenergic receptor agonist introduced recently to clinical practice for OAB patients, which offers an alternative option for to antimuscarinic drugs.

AREAS COVERED

This review presents the current knowledge concerning the mechanism of action, pharmacokinetics, and pharmacodynamics of vibegron. Moreover, it presents an overview of preclinical and phase II and phase III clinical studies on the efficacy, tolerability, and safety of this agent in patients suffering from OAB.

EXPERT OPINION

Clinical studies confirmed efficacy and safety of vibegron in OAB patients. Vibegron differ from well-known mirabegron with regards to its pharmacological profile because it is metabolized independently from CYP3A4, 2D6, or 2C9 and therefore is less likely to cause a drug-drug interaction. Moreover, since this drug does not penetrate the blood-brain barrier, it could become the drug of choice in OAB patients with cognitive impairment. These properties have paved the way in near future for better-tailored treatments for OAB patients.

Recent advances in managing overactive bladder

Overactive bladder syndrome (OAB) is defined as urinary urgency, usually accompanied by frequency and nocturia, with or without urgency incontinence, in the absence of urinary tract infection or other obvious pathology. In this review, we focus on recent advances in the management of OAB. We examine the evidence on the effect of anticholinergic load on OAB patients. Advances in medical treatment include a new beta-3 agonist, vibegron, which is thought to have fewer drug interactions than mirabegron. Treatment of genitourinary syndrome of the menopause with oestrogens and ospemifene have also shown promise for OAB. Botulinum toxin has been shown to be an effective treatment option. We discuss the new implantable neuromodulators that are on the market as well as selective bladder denervation and laser technology.

Pharmacotherapeutic management of lower urinary tract symptoms in Multiple Sclerosis patients

INTRODUCTION

Multiple Sclerosis (MS) manifests with a plethora of signs and symptoms affecting brain structures and spinal pathways. The multitude of lesions in MS patients makes difficult to establish the relative role of each of them to lower urinary tract symptoms (LUTS). Generally, the subcortical white-matter lesions result in detrusor overactivity, whilst lesions of the spinal cord result in the combined occurrence of detrusor overactivity and detrusor-sphincter dyssynergia (DSD). It has been estimated that 80-90% of patients with MS will suffer from some form of LUTS over the course of the disease. Among LUTS, the most reported is detrusor overactivity which includes urinary urgency, frequent urination, nocturia, and urge urinary incontinence.

AREAS COVERED

The authors review the management of lower urinary tract symptoms in MS patients providing their expert opinions on the subject matter.

EXPERT OPINION

LUTS affect the quality of life substantially and are associated with a significantly increased mortality. The adequate management is an important challenge for both patients and caregivers with a multidisciplinary approach likely necessary.

OnabotulinumtoxinA is a well tolerated and effective treatment for refractory overactive bladder in real-world practice

Introduction and hypothesis

In randomized clinical trials onabotulinumtoxinA was demonstrated to be an effective and well-tolerated treatment for overactive bladder (OAB) with urinary incontinence (UI). However, data reporting onabotulinumtoxinA use in everyday clinical practice are limited. Here, we present the results from a large, first-of-its-kind real-world study in patients with OAB.

Methods

This was a prospective, observational, multinational study (GRACE; ClinicalTrials.gov, NCT02161159) performed in four European countries. Patients (N = 504) aged ≥ 18 years with OAB inadequately managed with ≥ 1 anticholinergic received onabotulinumtoxinA per their physician’s normal clinical practice.

Results

Physicians primarily used rigid cystoscopes for onabotulinumtoxinA injection; anesthesia/analgesia was utilized during most treatment procedures. Significant reductions in UI episodes/day from baseline to weeks 1 and 12 were observed as well as in micturition, urgency, and nocturia episodes/day. These improvements in urinary symptoms corresponded to higher scores on the treatment benefit scale at week 12. The use of other OAB medications dropped from baseline to weeks 1 and 12 and was sustained to week 52, which paralleled a reduction in the number of incontinence products used during that time frame. Adverse reactions were reported in 2.6% of patients throughout the study.

Conclusions

In this real-world study, significant improvements in urinary symptoms were seen following onabotulinumtoxinA treatment as early as week 1 and sustained to at least week 12. This was accompanied by a reduced reliance upon incontinence products and reduction in concomitant OAB medication use. OnabotulinumtoxinA was well tolerated with no new safety signals.

Electronic supplementary material

The online version of this article (10.1007/s00192-020-04423-0) contains supplementary material, which is available to authorized users.

Therapeutic efficacy of mirabegron 25 mg monotherapy in patients with nocturia-predominant hypersensitive bladder

Objective:

The objective of this study was to evaluate the efficacy of mirabegron 25 mg daily in patients with nocturia-predominant hypersensitive bladder (HSB).

Materials and Methods:

This study prospectively investigated 219 consecutive patients with nocturia-predominant HSB and treated with mirabegron 25 mg daily from July 2015 to 2016. Patient with nocturia episode decreased by ≥1/night after treatment was considered successful. The subjective symptom score, such as International Prostate Symptom Score (IPSS), Quality of life index, Overactive Bladder Symptom Score (OABSS), Urgency Severity Scale, patient perception of bladder condition (PPBC), and nocturia episodes per night, was assessed before and 1 month after mirabegron treatment and between successful and failed groups.

Results:

A total of 219 patients, including 51 women and 168 men, were enrolled. The mean age of the population was 72.3 ± 11.0 years. Totally, 58 (26.5%) of the patients had improvement in nocturia at 1 month after treatment. Among them, 14 (27.5%) women and 44 (26.2%) men had improvement in nocturia episodes after treatment (P = 0.858). Compared the clinical data between successful and failed group, the baseline symptom scores were more severe in successful group, including IPSS-storage subscore (4.84 ± 2.09 vs. 4.11 ± 2.19, P = 0.031), OABSS (3.21 ± 0.67 vs. 2.91 ± 1.00, P = 0.037), and nocturia episodes (3.81 ± 0.95 vs. 3.095 ± 1.32, P = 0.000). Multivariate analysis revealed only a higher nocturia episodes (P = 0.046) predict a successful treatment result. Mirabegron 25 mg daily significantly improved PPBC score along the 3 months' follow-up (P < 0.05), and postvoid residual volume did not increase after mirabegron treatment in overall patients.

Conclusions:

Mirabegron 25 mg daily treatment showed a limited therapeutic effect on nocturia-predominant HSB patients. The patients with higher OAB symptoms predict a successful result.

Comparative Effectiveness of Transurethral Prostate Procedures at Enabling Urologic Medication Discontinuation: A Retrospective Analysis

OBJECTIVE

To test the hypothesis that transurethral prostate procedures (TUPPs) eliminating tissue result in greater medication discontinuation and lower de novo initiation rates than procedures inducing tissue necrosis.

METHODS

Retrospective review of all men undergoing first time TUPPs at a large tertiary center from 2001 to 2016 was completed. Procedure type and urologic medication use before, 3-12 months after, and greater than 12 months after TUPP were analyzed with simple open prostatectomy as a comparator. Tissue-eliminating TUPPs included transurethral resection of the prostate and laser prostatectomy. Tissue-necrosing procedures included microwave therapy (transurethral microwave therapy) and radiofrequency ablation (transurethral needle ablation), which were grouped in analyses. Medication types were 5-alpha reductase inhibitors (5ARI), alpha blockers, anticholinergics, and beta-3 agonists (B3A).

RESULTS

A total 5150 TUPPs were analyzed. Preoperative medication use significantly varied across TUPPs for 5ARI (P <.01), alpha-blockers (P .01), and anticholinergics (P .047), but not B3A (P .476). Transurethral resection of the prostate and laser prostatectomy were associated with significantly higher medication discontinuation rates and lower resumption and initiation rates compared to tissue-necrosing procedures. Relative to TUPPs, simple prostatectomy had significantly higher medication discontinuation, as well as the lowest resumption and initiation rates.

CONCLUSION

Tissue-eliminating benign prostatic hyperplasia procedures were associated with better medication discontinuation, resumption, and de novo initiation rates compared to tissue-necrosing benign prostatic hyperplasia procedures.

Relative Risk of Adverse Events and Treatment Discontinuations Between Older and Non-Older Adults Treated with Antimuscarinics for Overactive Bladder: A Systematic Review and Meta-Analysis

INTRODUCTION

Overactive bladder (OAB) affects adults of all ages. The risk for medication-related adverse events (AEs) may differ between age groups, given age-related changes in pharmacokinetics and pharmacodynamics. No previous study has differentiated the risk of AEs between older and non-older adults with OAB.

OBJECTIVE

Our objective was to assess the risk of AEs and treatment discontinuations between older and non-older adults with OAB initiated on an antimuscarinic.

METHODS

We searched MEDLINE (PubMed interface), Embase, SCOPUS, and Cochrane Central Register for Controlled Trials in a previous analysis in February 2015 and repeated the search in August 2018, with no additional studies identified. Studies that delineated AEs or treatment discontinuations between the older and non-older (age <65 years) subjects were included.

RESULTS

Six studies that made nine comparisons between older and non-older subjects met the inclusion criteria. The AEs of dry mouth (46.7%), constipation (10.3%), and headache (7.7%) were most frequently reported. Older subjects were more likely to experience dry mouth (relative risk [RR] 1.09; 95% confidence interval [CI] 1.00-1.19), constipation (RR 1.92; 95% CI 1.52-2.43), dizziness (RR 2.37; 95% CI 1.21-4.62), and urinary retention (RR 4.17; 95% CI 1.76-9.89) than were non-older subjects. Headache was less likely to occur in older subjects (RR 0.58; 95% CI 0.40-0.86). Treatment discontinuations due to AEs were more likely to occur in the older subjects (RR 1.59; 95% CI 1.20-2.11).

CONCLUSION

Treatment of OAB with antimuscarinics in the older population resulted in significantly higher rates of AEs, barring headache, when compared with non-older subjects.

Detailed insight on β-adrenoceptors as therapeutic targets

Human G protein-coupled receptors (GPCRs), especially adrenoceptors, play a crucial role in maintaining important physiological activities including cardiovascular and pulmonary functions. Among all adrenoceptors, β-adrenoceptors are the best characterized GPCRs and possess distinctive features as drug targets. Similarly, ligands that activate/deactivate β-adrenoceptors also hold a significant position in the field of biomarker identification and drug discovery. Several studies regarding molecular characterization of the β-adrenoceptor ligands have revealed that ligands with abilities to inhibit basal or intrinsic receptor activity or prevent receptor desensitization are particularly important to efficiently manage detrimental health conditions, including chronic heart failure, asthma, chronic obstructive pulmonary disease, obesity, and diabetes. Given the importance of β-adrenoceptors as molecular targets for many pathological conditions, this review aims to provide a detailed insight on the structural and functional aspects of β-adrenoceptors, with a particular emphasis on their importance as biomarkers and therapeutic targets.

Determination of Mirabegron in rat plasma by UPLC-MS/MS after oral and intravenous administration

Mirabegron is a kind of β3 adrenergic receptor agonist which is an effective drug for the treatment of overactive bladder. In this research, a UPLC-MS/MS method is developed and validated for the study of mirabegron pharmacokinetic in rats. A protein precipitation method is applied for sample preparation with acetonitrile. m/z 397.3→379.6, m/z 326.4→121.0 for mirabegron, tolterodine (IS), respectively in the positive ion mode was performed for quantitation. The method is reliable and reproducible in our study (intra-day precision≤11.06%, inter-day precision≤11.43%) with concentration curves linear from 5 to 2500 ng/mL(R2>0.999). Stability studies demonstrated that mirabegron was stable under a variety of storage conditions. This method was successfully applied for determining mirabegron in rats after oral and intravenous administration.

Selective bladder denervation for overactive bladder (OAB) syndrome: From concept to healing outcomes using the ovine model

Aims:

We evaluated a Selective Bladder Denervation (SBD) device, which uses radiofrequency ablation, for the treatment of overactive bladder syndrome in terms of its nerve denervation, ablation characteristics, and post-treatment healing.

Methods:

Using the SBD device, eight fresh extirpated ovine bladder trigones were treated (90°C set point for 60 s) and nitroblue tetrazolium viability stained to characterize the ablation. In addition, 12 trigones were treated in vivo with three adjacent ablations and divided into survival cohorts: Day 7, Day 30, and Day 90 to assess the ablations and their associated healing.

Results:

The ex vivo single trigone ablations had a 7.9 ± 0.9 mm width and 5.7 ± 1.0 mm thickness that involved the submucosa, detrusor muscle, adventitia, and vagina. Microscopic viability staining confirmed complete nerve necrosis within the targeted tissue. The in vivo Day 7 trigones supported the ex vivo ablation characteristics and showed up to minimal inflammation, granulation tissue, and collagen fibrosis. Day 30 trigones had essentially absent inflammation and granulation tissue with evolving collagen fibrosis at the ablation's periphery. Day 90 trigones had essentially absent acute inflammation, minimal chronic inflammation, essentially absent granulation tissue, and up to mild collagen fibrosis. No ureteral/urethral alterations, vesico-vaginal fistulas, or other complications were identified.

Conclusions:

The SBD device provided a targeted trigone ablation with resultant denervation. The tissue healing timeline followed that expected for a hyperthermic ablation and was characterized by a fibroproliferative healing response with limited inflammation and granulation tissue. The ablations did not impact the overlying bladder mucosal surface.

Discovery of Novel Indazole Derivatives as Orally Available β3-Adrenergic Receptor Agonists Lacking Off-Target-Based Cardiovascular Side Effects

We previously discovered that indazole derivative 8 was a highly selective β₃-adrenergic receptor (β₃-AR) agonist, but it appeared to be metabolically unstable. To improve metabolic stability, further optimization of this scaffold was carried out. We focused on the sulfonamide moiety of this scaffold, which resulted in the discovery of compound 15 as a highly potent β₃-AR agonist (EC₅₀ = 18 nM) being inactive to β₁-, β₂-, and α_1A-AR (β₁/β₃, β₂/β₃, and α_1A/β₃ > 556-fold). Compound 15 showed dose-dependent β₃-AR-mediated responses in marmoset urinary bladder smooth muscle, had a desirable metabolic stability and pharmacokinetic profile (C_max and AUC), and did not obviously affect heart rate or mean blood pressure when administered intravenously (3 mg/kg) to anesthetized rats. Thus, compound 15 is a highly potent, selective, and orally available β₃-AR agonist, which may serve as a candidate drug for the treatment of overactive bladder without off-target-based cardiovascular side effects.

Investigation of piperazine benzamides as human β3 adrenergic receptor agonists for the treatment of overactive bladder

The synthesis of a novel class of piperazine benzamide (reverse amides) targeting the human β₃-adrenergic receptor for the treatment of overactive bladder (OAB) is described. The SAR studies directed towards maintaining well established β₃ potency and selectivities while improving the overall pharmacokinetic profile in the reverse amide class will be evaluated. The results and consequences associated with functional activity at the norepinephrine transporter (NET) will also be discussed.