New developments in the management of overactive bladder: focus on mirabegron and onabotulinumtoxinA

Examining the safety of mirabegron: an analysis of real-world pharmacovigilance data from the US FDA adverse event reporting system (FAERS) database

Background: Mirabegron, the first β-3 adrenergic receptor agonist, received approval from the Food and Drug Administration (FDA) in 2012 for the treatment of overactive bladder (OAB). This pharmacovigilance study investigated the safety profile of mirabegron treatment using the US FDA Adverse Event Reporting System (FAERS) database. Methods: This study employed disproportionality analyses, including the reporting odds ratio (ROR) and Bayesian Confidence Propagation Neural Network (BCPNN) algorithm, to quantify signals of adverse events associated with mirabegron. Results: From the first quarter of 2012 to the third quarter of 2023, a comprehensive total of 14,356,234 adverse event (AE) reports were submitted to the FDA Adverse Event Reporting System database. Within this dataset, encompassing 18,763 reports specifically associated with mirabegron, healthcare professionals notably contributed 2,902 of these reports. A total of 80 preferred terms (PTs) of interest were identified using both the ROR and information component algorithms. The most common AEs included blood pressure increased, urinary retention, atrial fibrillation, dry mouth, and tachycardia, which were consistent with the product instructions. Unexpected significant AEs, such as arrhythmia, palpitations, dementia, transient ischemic attack, Parkinson's disease, anti-neutrophil cytoplasmic antibody positive vasculitis, lip swelling, and swollen tongue, were also identified. The study findings indicated that the majority of onset time occurred within 30 days (n = 358, 55.68%). However, AEs were still possible after 1 year of mirabegron treatment. Conclusion: This study provided valuable evidence for the real-world safety of mirabegron, helping clinical professionals enhance their understanding of mirabegron's safety in clinical practice. It also contributed valuable evidence for further safety studies on mirabegron.

Relationship Between Marijuana Use and Overactive Bladder (OAB): A Cross-Sectional Research of NHANES 2005 to 2018

BACKGROUND

Current research is starting to focus on the medical value of marijuana and the possible health problems it can cause. Previous studies have shown that marijuana can relieve lower urinary tract symptoms, which can pose a significant public health burden. In this study, we assessed the association between regular marijuana use and overactive bladder as part of low urinary tract symptoms.

METHODS

Data from the National Health and Nutrition Examination Survey 2005-2018 were obtained for analysis. The Overactive Bladder Symptom Score scale was used to define the presence of overactive bladder for each participant. Multivariate logistic regression and ordinal logistic regression were used to analyze the association of marijuana use with the onset and severity of overactive bladder, respectively.

RESULTS

We found that approximately 24% of the US population reported regular marijuana use. Compared with nonregular users, regular marijuana users were younger, thinner, more likely to be male, smokers, low-income, less educated, unmarried, and non-Hispanic White/Black. Multivariate logistic regression revealed that marijuana exposure may be an independent risk factor for overactive bladder (odds ratio 1.39; 95% confidence interval, 1.16-1.66). Ordinal logistic regression results showed that marijuana exposure was associated with the severity of overactive bladder (odds ratio 1.45; 95% confidence interval, 1.30-1.60). Moreover, all frequencies of regular use showed almost consistent effects on the onset and severity of overactive bladder.

CONCLUSION

Regular marijuana use may increase the risk of overactive bladder. Our data do not support the evidence for the use of cannabinoids in the medical treatment of patients with overactive bladder, especially given the thorny health problems caused by marijuana.

Mirabegron in the Management of Overactive Bladder Syndrome

Overactive bladder (OAB) negatively affects work productivity and quality of life in sufferers. Its overall impact is likely to increase as a result of increasing prevalence in an ageing population. The pathophysiology of OAB is not completely understood but the β3-adrenoceptor, which is highly expressed in the urinary bladder, is thought to be important for mediating human detrusor relaxation during the storage phase. Clinical trial results have demonstrated that mirabegron, a selective β3-adrenoceptor agonist offers substantial clinical efficacy and good adherence rates over 12 months. Furthermore, due to its different mechanism of action, it is likely to offer a favourable tolerability profile when compared with antimuscarinic agents, resulting in improved persistence over long-term treatment. Finally, from a health economic perspective, despite its higher drug acquisition cost, mirabegron has been found to be cost-effective, owing to the greater increase in quality-adjusted-life-years gained, when compared to antimuscarinic medications. The PubMed database was searched for English language articles published between 1 January 2005 to 31 January 2022, on the subject of mirabegron. Search terms included "mirabegron", "overactive bladder", "β3-adrenoceptor agonist", "urinary incontinence". This review summarises the evidence for mirabegron as a treatment option for the management of OAB.

Combination Pharmacotherapy for Treatment of Overactive Bladder (OAB)

Overactive bladder syndrome (OAB) negatively affects the quality of life of patients and their interactions with society. Treatment of OAB starts with behavioral modification and then pharmacotherapy using monotherapy with either antimuscarinics or β3 agonists. The third-line more invasive approaches are the next treatment option currently recommended. Both antimuscarinic agents and β3 agonists work through a different molecular pathway. This brings up the potential of having an additive effect when using a combination treatment for patients with OAB. Currently, the potential for using combination therapy to treat OAB in patients who had no improvement with a monotherapy approach before we attempt a more invasive approach is being explored. Several studies have shown the benefits of combination therapy which will be an additional option to the tools to treat OAB.

Bladder drug mirabegron exacerbates atherosclerosis through activation of brown fat-mediated lipolysis

Mirabegron (Myrbetriq) is a β3-adrenoreceptor agonist approved for treating overactive bladder syndrome in human patients. This drug can activate brown adipose tissue (BAT) in adult humans and rodents through the β3-adrenoreceptor-mediated sympathetic activation. However, the effect of the mirabegron, approved by the US Food and Drug Administration, on atherosclerosis-related cardiovascular disease is unknown. Here, we show that the clinical dose of mirabegron-induced BAT activation and browning of white adipose tissue (WAT) exacerbate atherosclerotic plaque development. In apolipoprotein E^-/- (ApoE ^-/-) and low-density lipoprotein (LDL) receptor^-/- (Ldlr ^-/-) mice, oral administration of clinically relevant doses of mirabegron markedly accelerates atherosclerotic plaque growth and instability by a mechanism of increasing plasma levels of both LDL-cholesterol and very LDL-cholesterol remnants. Stimulation of atherosclerotic plaque development by mirabegron is dependent on thermogenesis-triggered lipolysis. Genetic deletion of the critical thermogenesis-dependent protein, uncoupling protein 1, completely abrogates the mirabegron-induced atherosclerosis. Together, our findings suggest that mirabegron may trigger cardiovascular and cerebrovascular diseases in patients who suffer from atherosclerosis.

Long-term Safety and Efficacy of Mirabegron and Solifenacin in Combination Compared with Monotherapy in Patients with Overactive Bladder: A Randomised, Multicentre Phase 3 Study (SYNERGY II)

BACKGROUND

The long-term potential of solifenacin and mirabegron combination treatment for patients with overactive bladder (OAB) has not been previously assessed.

OBJECTIVES

To evaluate the safety and efficacy of solifenacin succinate 5mg plus mirabegron 50mg tablets (combination treatment) versus solifenacin or mirabegron monotherapy in patients with OAB over 12 mo.

DESIGN, SETTING, AND PARTICIPANTS

Randomised, double-blind, multicentre, phase 3 trial (SYNERGY II) of patients with "wet" OAB symptoms (urinary frequency and urgency with incontinence) for ≥3 mo. The study was conducted from March 2014 to September 2016; with 1829 patients randomised. The full analysis set was comprised of 1794 patients.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary objective was safety, measured as treatment-emergent adverse events (TEAEs). Efficacy was measured as the change from baseline to the end of treatment in the mean number of incontinence episodes/24h and micturitions/24h.

RESULTS AND LIMITATIONS

The median age was 60 yr (range 19-86 yr) and 1434 patients (80%) were female. Overall, 856 patients (47%) experienced ≥1 TEAE. TEAE frequency was slightly higher in the combination group (596 patients, 49%; mirabegron 126 patients, 41%; solifenacin 134 patients, 44%). Serious TEAEs were reported by 67 patients (3.7%); one was considered possibly treatment-related (mirabegron group, atrial fibrillation). Dry mouth was the most common TEAE (combination 74 patients, 6.1%; solifenacin 18 patients, 5.9%; mirabegron 12 patients, 3.9%). Combination therapy was statistically superior to mirabegron and solifenacin for the number of incontinence episodes (vs mirabegron: adjusted mean difference [AMD] -0.5, 95% confidence interval [CI] -0.7 to -0.2, p<0.001; vs solifenacin: AMD -0.1, 95% CI -0.4 to 0.1, p=0.002) and micturitions (vs mirabegron: AMD -0.5, 95% CI -0.8 to -0.2, p<0.001; vs solifenacin: AMD -0.4, 95% CI -0.7 to -0.1, p=0.004).

CONCLUSIONS

Mirabegron and solifenacin combination treatment for OAB symptoms was well tolerated over 12 mo and led to efficacy improvements over each monotherapy. This innovative combination is a treatment option that could become widely used in the clinic.

PATIENT SUMMARY

This study looked at the safety and efficacy of a combination of solifenacin succinate 5mg plus mirabegron 50mg tablets over 12 mo in patients with the overactive bladder (OAB) symptoms of increased urination frequency, heightened urgency to urinate, and unintentional passing of urine. We compared this treatment with solifenacin succinate 5mg or mirabegron 50mg alone, and found that the combination treatment was well tolerated by patients and led to greater improvements in symptoms. This novel combination could be an improved treatment option in the clinical setting for patients with OAB. This study is registered at ClinicalTrials.gov as NCT02045862.

Overactive bladder treatment: application of methylene blue to improve the injection technique of onabotulinum toxin A

OBJECTIVE

The aim of this study was to test the addition of methylene blue (MB) to onabotulinum toxin A (BTX-A) solution in overactive bladder (OAB) treatment, as a means of facilitating observation of the injection site and assessing the distribution of the drug under the bladder mucosa during injection. Pharmacological interactions between BTX-A and MB were also evaluated.

MATERIALS AND METHODS

The study was conducted between December 2014 and April 2016 on 30 patients: six males and 24 females (median age 57.7, range 23-80 years) diagnosed with OAB, who qualified for intravesical BTX-A injection. Each received 100 IU of BTX-A (Botox^®; Allergan), dissolved in 9.5 ml of 0.9% NaCl with the addition of 0.5 ml of MB. Cystoscopy with submucosal injection of the solution was performed systematically, including the bladder triangle. For pharmacological evaluation, quantitative determination of MB was performed on a capillary electrophoresis system with diode array detection.

RESULTS

In the course of 600 injections, the addition of MB facilitated the observation of the procedure; the exact distribution of the solution could not be observed in only 43 injections in seven patients. The range of distribution of the drug varied from 1 to 2.5 cm. Pharmacological evaluation based on visual observations and experiments showed that pharmaceutical interactions do not occur between MB and this commercially available formulation of BTX-A.

CONCLUSIONS

Applying a coloured solution of BTX-A significantly facilitates observation of the procedure and assessment of drug distribution. There are no pharmaceutical interactions between MB and BTX-A.

Comparative assessment of the efficacy of onabotulinumtoxinA and oral therapies (anticholinergics and mirabegron) for overactive bladder: a systematic review and network meta-analysis

OBJECTIVES

To compare the efficacy of onabotulinumtoxinA, mirabegron, and anticholinergics in adults with idiopathic overactive bladder (OAB) using network meta-analysis (NMA).

PATIENTS AND METHODS

Information sources were searched for blinded randomised controlled trials (RCTs), of ≥2 weeks duration, comparing any dose of onabotulinumtoxinA, eligible oral/transdermal anticholinergics, or mirabegron, with each other or placebo, in adults with OAB. Bayesian random-effects models were used to synthesise the results at week 12: NMA for responder analyses and network meta-regression (NMR) for change from baseline analyses. The NMR was used to adjust for differences in baseline severity between studies. Sensitivity analysis, excluding studies considered to be at a high risk of methodological bias, was conducted.

RESULTS

In all, 56 RCTs were included in the networks. For each outcome, results are reported for all licensed treatment doses. For each NMR, results are based on patients with an average number of episodes of the outcome at baseline. After 12 weeks, all treatments were more efficacious than placebo. Patients who received onabotulinumtoxinA (100 U) had, on average, the greatest reductions in urinary incontinence episodes (UIE), urgency episodes, and micturition frequency, and the highest odds of achieving decreases of 100% and ≥50% from baseline in UIE/day. When comparing onabotulinumtoxinA with other pharmacotherapies, mean differences favoured onabotulinumtoxinA 100 U over all comparators for UIE and urgency episodes (credible intervals excluded zero) and all but two of the comparators for micturition frequency. OnabotulinumtoxinA 100 U was also associated with higher odds of achieving a 100% and ≥50% decrease in UIE/day than most other licensed treatments in the network. The exclusion of studies with a high risk of bias had little impact on the conclusions.

CONCLUSION

The results indicate that, after 12 weeks, onabotulinumtoxinA 100 U provides greater relief of OAB symptoms compared with most other licensed doses of other pharmacotherapies in the network.

An Exploratory Study in Healthy Male Subjects of the Mechanism of Mirabegron-Induced Cardiovascular Effects

To explore the role of β₁ -adrenoceptors (ARs) in the heart rate response to the selective β₃ -adrenoceptor agonist mirabegron, 12 young male volunteers received single oral doses of the nonselective β_1/2 -AR antagonist propranolol (160 mg), the selective β₁ -AR antagonist bisoprolol (10 mg), or placebo on days 1 and 5 of each period in a 3-period crossover study. On day 5, dosing was followed by a supratherapeutic dose of mirabegron (200 mg). Vital signs, impedance cardiography, and plasma renin activity were collected. Mirabegron increased heart rate and systolic blood pressure and reduced stroke volume, whereas cardiac output and diastolic blood pressure were unaffected. Mirabegron-induced changes were attenuated by propranolol and bisoprolol. The data indicate that mirabegron has a positive chronotropic effect at supratherapeutic concentrations, which is at least partly mediated by stimulation of β₁ -AR.

Efficacy and safety of onabotulinum toxin A for overactive bladder

Overactive bladder (OAB) syndrome is a condition which affects 16.9% of women and 16.2% of men with a significant negative impact on quality of life. It is a condition characterized by urgency, with or without urge incontinence, frequency and nocturia. Behavioral modifications and oral anti-muscurinic medications are first and second-line therapies for OAB but are frequently ineffective or poorly tolerated. For refractory cases of OAB, onabotulinum toxin can be offered and this therapy was approved by the Food and Drug Administration in January of 2013. In this editorial, we will review the indications, usage, efficacy and safety data for intradetrusor injection of onabotulinum toxin A.

17Beta-Estradiol Inhibits Calcium-Activated Potassium Channel Expressions in Rat Whole Bladder

Purpose:

To investigate the effect of estrogen on the expression of calcium-activated potassium (K_Ca) channels in an overactive bladder rat model. To this end, mRNA and protein levels of K_Ca channel subtypes in the bladder of ovariectomized rats were measured by reverse transcription polymerase chain reaction and western blotting, respectively.

Methods:

Ten-week-old female Sprague-Dawley rats were divided randomly into 3 groups: sham-operated control group (n=11), ovariectomy group (n=11), and the group treated with estrogen after ovariectomy (n=12). Rats in the last group were subcutaneously injected with 17β-estradiol (50 μg/kg) every other day for 2 weeks, whereas rats in the other 2 groups received vehicle (soybean oil) alone. Two weeks after treatment, the whole bladder was excised for mRNA and protein measurements.

Results:

Protein levels of the large-conductance K_Ca (BK) channels in the ovariectomy group were 1.5 folds higher than those in the sham-operated control group. However, the protein levels of the other K_Ca channel subtypes did not change significantly upon bilateral ovariectomy. Treatment with 17β-estradiol after ovariectomy restored BK channel protein levels to the control value. In contrast, BK channel mRNA levels were not significantly affected by either ovariectomy alone or 17β-estradiol treatment. The small-conductance K_Ca type 3 channel (SK3) mRNA and protein levels decreased to 75% of control levels upon 17β-estradiol treatment.

Conclusions:

These results suggest that 17β-estradiol may influence urinary bladder function by modulating BK and SK3 channel expression.

Comparative assessment of onabotulinumtoxinA and mirabegron for overactive bladder: an indirect treatment comparison

CONTEXT

OnabotulinumtoxinA and mirabegron have recently gained marketing authorisation to treat symptoms of overactive bladder (OAB).

OBJECTIVE

To evaluate the relative efficacy of mirabegron and onabotulinumtoxinA in patients with idiopathic OAB.

DESIGN

Network meta-analysis.

DATA SOURCES

A search of 9 electronic databases, review documents, guidelines and websites.

METHODS

Randomised trials comparing any licensed dose of onabotulinumtoxinA or mirabegron with each other, anticholinergic drugs or placebo were eligible (19 randomised trials were identified). 1 reviewer extracted data from the studies and a second reviewer checked the data. Candidate trials were assessed for similarity and networks were developed for each outcome. Bayesian network meta-analysis was conducted using both fixed-effects and random-effects models. When there were differences in mean baseline values between mirabegron and onabotulinumtoxinA trials they were adjusted for using network meta-regression (NMR).

RESULTS

No studies directly comparing onabotulinumtoxinA to mirabegron were identified. A network was created for each of the 7 outcomes, with 3-9 studies included in each individual network. The trials included in the networks were broadly similar. Patients in the onabotulinumtoxinA trials had more urinary incontinence and urgency episodes at baseline than patients in the mirabegron trials and these differences were adjusted for using NMR. Both onabotulinumtoxinA and mirabegron were more efficacious than placebo at reducing the frequency of urinary incontinence, urgency, urination and nocturia. OnabotulinumtoxinA was more efficacious than mirabegron (50 and 25 mg) in completely resolving daily episodes of urinary incontinence and urgency and in reducing the frequency of urinary incontinence, urgency and urination. NMR supported the results of the network meta-analysis.

CONCLUSIONS

In the absence of head-to-head trials comparing onabotulinumtoxinA to mirabegron, this indirect comparison indicates that onabotulinumtoxinA may be superior to mirabegron in improving symptoms of urinary incontinence, urgency and urinary frequency in patients with idiopathic OAB.

Influence of different doses of trospium and solifenacin on manageability of OAB symptoms with different severity in elderly men and women

Objective:

We studied the rationale for using standard and increased dosages of solifenacin and trospium against overactive bladder (OAB) symptoms of different severity among elderly patients.

Methods:

A total of 327 patients took part in the study: 199 women and 128 men older than 65 years (median age 69.1). The state of the lower urinary tracts was estimated by cystometry, ICIQ-SF and bladder diaries. Frequency of urgency urinary incontinence (UUI) was taken as a criterion of OAB symptom severity.

Result:

Administration of double-dosed trospium and solifenacin leads to decrease of frequency of UUI both in the group with severe symptoms (B1: 6.1 (0.5) →2.4 (0.9), p ⩽ 0.05), and in the group with moderate symptoms of OAB (A1: 2.8 (0.8) →0.5 (0.4), p ⩽ 0.001). Under a combination of trospium and solifenacin in doses recommended by manufacturers, UUI decreased authentically in the group with moderate symptoms (A2: 2.9 (0.5) →0.9 (0.5), p ⩽ 0.05) and unauthentically in the group with severe symptoms of detrusor dysfunction (B2: 7.0 (1.2) → 4.3 (1.5), p ⩾ 0.05). During the experiment six patients (1.8%) elected not to participate because of intolerable adverse events. Forty-seven more individuals (14.4%) felt adverse effects, among which the most frequent were: xerostomia (15 patients or 4.6%), faintness (nine patients or 3.8%), dryness of integuments (six patients or 1.8%).

Conclusion:

A standard-dose combination of solifenacin and trospium in older patients with moderate symptoms of OAB enables a good therapeutic effect in a short time without increasing risk of side effects. High therapeutic doses of antimuscarinic drugs are reasonable for older men and women with severe symptoms of OAB. Increasing the dose of simultaneous use of solifenacin and trospium yields a good therapeutic effect to correct UUI; however, it raises the hazard of appearance of adverse effects. The number of side effects in the group of elderly individuals who were taking the combination of increased and standard dosages of solifenacin and trospium does not significantly differ.

A randomized, controlled trial of effectiveness and safety of management of OAB symptoms in elderly men and women with standard-dosed combination of solifenacin and mirabegron

OBJECTIVES

Comparison of effectiveness and safety of solifenacin and mirabegron, as well as their combination, for managing heavy symptoms of overactive bladder.

MATERIALS AND METHODS

All patients who participated in the examination (average age: 71.2) were split into 4 groups. Patients included in Group А (n=63) were treated with mirabegron 50mg/day/6 weeks, in Group B (n=52)-with solifenacin 10mg/day/6 weeks, in Group С (n=65)-with the same doses of both drugs simultaneously/6 weeks, and in Group D (n=59)-with placebo. Monitoring was carried out using OAB-questionnaires, bladder diaries and urodynamic examination.

RESULTS

In elderly patients with initial frequency of episodes of incontinence (EI)≥3/day standard doses of mirabegron (50mg/day) and solifenacin 10mg/day administered during 6 weeks result with the decrease in frequency of EI with high correlation (r=0,74, p≤0.05); final results in both groups are significantly different from initial value of p≤0.05. In the group, where patients were taking both drugs simultaneously, final results significantly differ from both initial values of the parameters in these groups (EI: 5.1→1.6 per day, p≤0.01; urination: 9.1→5.3 per day, p≤0.01; post-void residual 19.4→29.9, p≤0.01) and final values in Groups A and B (p≤0.05). The percentage of side effects in this group does not significantly differ from that in the groups, where patients were receiving monotherapy.

CONCLUSION

Combined treatment for severe symptoms of OAB in elderly men and women with standard doses of solifenacin and mirabegron provides satisfactory therapeutic effect within short period of time without increasing the risk of side effects, which undoubtedly improves quality of life and self-esteem of patients. At the same time, taking any of these drugs separately for the treatment of severe malfunction of lover urinary tracts in elderly people may turn out to be insufficient for effective symptom management.

Involvement of β3-adrenoceptors in the inhibitory control of cholinergic activity in human bladder: Direct evidence by [(3)H]-acetylcholine release experiments in the isolated detrusor

Bladder overactivity (OAB) is a multifactorial bladder disorder that requires therapeutics superior to the current pharmacological treatment with muscarinic antagonists. β3-adrenoceptor (β3-ADR) agonists represent a novel promising approach that differently addresses the parasympathetic pathway, but the clinical efficacy of these drugs has not been fully elucidated to date. Therefore, we aimed to study the pharmacological mechanisms activated by β3-ADR agonists at muscular and neural sites in the isolated human bladder. Detrusor smooth muscle strips obtained from male patients undergoing total cystectomy were labelled with tritiated choline and stimulated with electrical field stimulation (EFS). EFS produced smooth muscle contraction and simultaneous acetylcholine ([(3)H]-ACh) release, which mostly reflects the neural origin of acetylcholine. Isoprenaline (INA), BRL37344 and mirabegron inhibited the EFS-evoked contraction and [(3)H]-ACh release in a concentration-dependent manner, yielding concentration-response curves (CRCs) that were shifted to the right by the selective β3-ADR antagonists L-748,337 and SR59230A. Based on the agonist potency estimates (pEC50) and apparent affinities (pKb) of antagonists evaluated from the CRCs of agonists, our data confirm the occurrence of β3-ADRs at muscle sites. Moreover, our data are consistent with the presence of inhibitory β3-ADRs that are functionally expressed at the neural site. Taken together, these findings elucidate the mechanisms activated by β3-ADR agonists because neural β3-ADRs participate in the inhibition of detrusor motor drive by reducing the amount of acetylcholine involved in the cholinergic pathway.

The potential role of stem cells in the treatment of urinary incontinence

Voiding dysfunction encompasses a wide range of urologic disorders including stress urinary incontinence and overactive bladder that have a detrimental impact on the quality of life of millions of men and women worldwide. In recent years, we have greatly expanded our understanding of the pathophysiology of these clinical conditions. However, current gold standard therapies often provide symptomatic relief without targeting the underlying etiology of disease development. Recently, the use of stem cells to halt disease progression and reverse underlying pathology has emerged as a promising method to restore normal voiding function. Stem cells are classically thought to aid in tissue repair via their ability for multilineage differentiation and self-renewal. They may also exert a therapeutic effect via the secretion of bioactive factors that direct other stem and progenitor cells to the area of injury, and that also possess antiapoptotic, antiscarring, neovascularization, and immunomodulatory properties. Local injections of mesenchymal, muscle-derived, and adipose-derived stem cells have all yielded successful outcomes in animal models of mechanical, nerve, or external urethral sphincter injury in stress urinary incontinence. Similarly, direct injection of mesenchymal and adipose-derived stem cells into the bladder in animal models of bladder overactivity have demonstrated efficacy. Early clinical trials using stem cells for the treatment of stress urinary incontinence in both male and female patients have also achieved promising functional results with minimal adverse effects. Although many challenges remain to be addressed prior to the clinical implementation of this technology, novel stem-cell-based therapies are an exciting potential therapy for voiding dysfunction.

Randomized controlled trial of cyclic and continuous therapy with trospium and solifenacin combination for severe overactive bladder in elderly patients with regard to patient compliance

OBJECTIVES

The aim of the study was to increase the efficiency of treatment for severe symptoms of overactive bladder (OAB) with antimuscarinic drugs in elderly men and women.

METHODS

A total of 341 patients over 65 years of age (average age 69.9; 186 women and 155 men) with severe symptoms of OAB (frequency of incontinence episodes [IEs] ≥ 3/day) underwent examination. Patients were distributed into three main groups: A (n = 58; trospium 60 mg/day + solifenacin 20): three cycles, each cycle 8 weeks, with an 8-week interval; B (n = 55; trospium 30 mg/day + solifenacin 10), regimen was the same as in group A; C (n = 62; trospium 30 mg/day + solifenacin 10) daily during 1 year.

RESULTS

The most successful treatment for the clinical and urodynamic symptoms of OAB was observed in group A, without an increase in the quantity or intensity of side effects (IEs = 4.8 (0.9) → 1.4 (0.8); p ≤ 0.01). Groups B and C also demonstrated positive effects for most of the markers for lower urinary tract state with statistical significance p ≤ 0.01. Nonparametric correlation between decrease in IEs and relative number of patients who accurately fulfilled prescriptions was in group A, r = 0.53, p ≤ 0.05; in group B, r = 0.61; p ≤ 0.05; in group C, r = 0.55, p ≤ 0.05.

CONCLUSIONS

Cyclic therapy with two different spectrum antimuscarinics appears to be effective for controlling severe OAB in elderly patients. One-year cyclic therapy with a trospium and solifenacin combination provides a high compliance level (76-84%). However, continuous therapy with standard doses of trospium and solifenacin results in low adherence and high rates of treatment withdrawals (≥ 66%) despite satisfactory clinical and urodynamic results.

Changes in prostaglandin E2 in patients with idiopathic overactive bladder syndrome after botulinum toxin type A treatment: is there a clinical benefit?

BACKGROUND

The causality of overactive bladder syndrome (OAB) is still not fully understood. Several studies indicate a significant increase of prostaglandin E2 (PGE2) in patients with OAB. However, in order to clarify whether these compounds can help to objectify the clinical diagnosis, further studies are needed. This prospective study aims to analyze PGE2 blood levels (sPGE2) in patients with OAB before and after botulinum toxin type A (BoNT-A) therapy.

METHODS

Blood samples were obtained from 56 patients (52y, 18-87) with idiopathic OAB. sPGE2 levels were measured before and 4 weeks after BoNT-A treatment by enzyme linked immunosorbent assay (ELISA). 31 healthy persons with normal bladder function served as control group (59 y, 21-72). sPGE2 was set in relation to clinical data and the severity of OAB (wet/dry). The statistical data analysis was performed by using the non-parametric Mann-Whitney U test and paired t-test.

RESULTS

Significant higher sPGE2 levels were detected in patients with OAB compared to members of the control group (2750 pg/ml vs. 1674 pg/ml, p < 0.005). Furthermore sPGE2 levels were increased in patients with OAB wet compared to OAB dry (p <0.01). In 30 patients sPGE2 levels decreased significantly after BoNT-A treatment compared to baseline (2995 pg/ml vs. 1486 pg/ml, p <0.005). Patients reported an average drug effect of 9 month (0-19); incontinence pads were needed significantly less frequent (p < 0.05). 3 patients reported no postoperative effect. sPGE2 increased in two patients compared to initial levels, a single patient showed a remotely decreased sPGE2. Six patients were treated repeatedly with BoNT-A after showing an sPGE2 re-rise.

CONCLUSIONS

sPGE2-level is increased in patients with OAB. We could prove a significant decrease of sPGE2 after BoNT-A treatment. In this small cohort we could demonstrate a correlation between OAB and sPGE2, especially in the non-responder group. The use of sPGE2 as a biomarker in diagnostics and follow-up after therapy seems promising. To what extent sPGE2 can be useful as such needs to be examined prospectively in a larger population.

OnabotulinumtoxinA for the treatment of overactive bladder

OnabotulinumtoxinA injection is a safe and effective treatment for adults with refractory overactive bladder. There is sufficient level 1 evidence to support offering onabotulinumtoxinA injections as a second-line treatment to patients who have failed behavioral therapy and oral medications such as antimuscarinics and β3 agonists. An intradetrusor injection of 100 U of onabotulinumtoxinA is likely the optimal dose to balance risks and benefits, and this is the dose approved by the US Food and Drug Administration. Improvement in urgency urinary incontinence episodes, as well as symptom scores and quality of life, were seen in around 60%-65% of patients, and were significantly improved compared with those on placebo. Most studies have reported a duration of symptom relief ranging from 6 to 12 months, with repeat injections being safe and efficacious. Overall, the risk of urinary retention was around 6% across the study populations.

Central role of the BK channel in urinary bladder smooth muscle physiology and pathophysiology

The physiological functions of the urinary bladder are to store and periodically expel urine. These tasks are facilitated by the contraction and relaxation of the urinary bladder smooth muscle (UBSM), also known as detrusor smooth muscle, which comprises the bladder wall. The large-conductance voltage- and Ca(2+)-activated K(+) (BK, BKCa, MaxiK, Slo1, or KCa1.1) channel is highly expressed in UBSM and is arguably the most important physiologically relevant K(+) channel that regulates UBSM function. Its significance arises from the fact that the BK channel is the only K(+) channel that is activated by increases in both voltage and intracellular Ca(2+). The BK channels control UBSM excitability and contractility by maintaining the resting membrane potential and shaping the repolarization phase of the spontaneous action potentials that determine UBSM spontaneous rhythmic contractility. In UBSM, these channels have complex regulatory mechanisms involving integrated intracellular Ca(2+) signals, protein kinases, phosphodiesterases, and close functional interactions with muscarinic and β-adrenergic receptors. BK channel dysfunction is implicated in some forms of bladder pathologies, such as detrusor overactivity, and related overactive bladder. This review article summarizes the current state of knowledge of the functional role of UBSM BK channels under normal and pathophysiological conditions and provides new insight toward the BK channels as targets for pharmacological or genetic control of UBSM function. Modulation of UBSM BK channels can occur by directly or indirectly targeting their regulatory mechanisms, which has the potential to provide novel therapeutic approaches for bladder dysfunction, such as overactive bladder and detrusor underactivity.

The cost-effectiveness of solifenacin vs. trospium in the treatment of patients with overactive bladder in the German National Health Service

OBJECTIVE

To carry out a cost-utility analysis comparing initial treatment of patients with overactive bladder (OAB) with solifenacin 5 mg/day versus either trospium 20 mg twice a day or trospium 60 mg/day from the perspective of the German National Health Service.

METHODS

A decision analytic model with a 3 month cycle was developed to follow a cohort of OAB patients treated with either solifenacin or trospium during a 1 year period. Costs and utilities were accumulated as patients transitioned through the four cycles in the model. Some of the solifenacin patients were titrated from 5 mg to 10 mg/day at 3 months. Utility values were obtained from the published literature and pad use was based on a US resource utilization study. Adherence rates for individual treatments were derived from a United Kingdom general practitioner database review. The change in the mean number of urgency urinary incontinence episodes/day from after 12 weeks was the main outcome measure. Baseline effectiveness values for solifenacin and trospium were calculated using the Poisson distribution. Patients who failed second-line therapy were referred to a specialist visit. Results were expressed in terms of incremental cost-utility ratios.

RESULTS

Total annual costs for solifenacin, trospium 20 mg and trospium 60 mg were €970.01, €860.05 and €875.05 respectively. Drug use represented 43%, 28% and 29% of total costs and pad use varied between 45% and 57%. Differences between cumulative utilities were small but favored solifenacin (0.6857 vs. 0.6802 to 0.6800). The baseline incremental cost-effectiveness ratio ranged from €16,657 to €19,893 per QALY.

LIMITATIONS

The difference in cumulative utility favoring solifenacin was small (0.0055-0.0057 QALYs). A small absolute change in the cumulative utilities can have a marked impact on the overall incremental cost-effectiveness ratios (ICERs) and care should be taken when interpreting the results.

CONCLUSION

Solifenacin would appear to be cost-effective with an ICER of no more than €20,000/QALY. However, small differences in utility between the alternatives means that the results are sensitive to adjustments in the values of the assigned utilities, effectiveness and discontinuation rates.

Effectiveness of combined high-dosed trospium and solifenacin depending on severity of OAB symptoms in elderly men and women under cyclic therapy

MATERIAL AND METHODS

313 patients, 196 women and 117 men over 65 (average age 68.6) were included in this study. All patients underwent urodynamic examination before enrollment and after the study was completed. For clinical evaluation of LUT state ICIQ-SF questionnaires and bladder diaries were used. Patients with moderate (А, n = 155) and severe (В, n = 158) symptoms of OAB. Each group was divided into subgroups in which patients received Trospium 60 mg/day and Solifenacin 20 mg/day during two cycles - 1.5 and 1 month with one month interval (А1 and В1); subgroups in which second cycle was substituted with placebo (А2, В2), and control groups (А3, В3).

RESULTS

In groups with moderate symptoms of OAB ratio of patients demonstrated decrease of frequency of EI ≥1.5 a day remained at the level of 45-60% during all observation period. In subgroups with severe symptoms of OAB percentage of such patients was 55.3% for the subgroup which received two cycle therapy, and decreased to 26% in the subgroup which underwent 1 cycle therapy. Urodynamic indices for state of LUT correlated with clinical indicators (r =0.57-0.71 at p≤ 0.05).

CONCLUSIONS

Short single cycle of high-dosed Solifenacin and Trospium in elderly patients with moderate symptoms of OAB enables to maintain long therapeutic effect with acceptable level of side effects. This treatment algorithm applied in two cycle course is an effective and safe method for management of severe symptoms of OAB in elderly patients without increased risk of side effects.

Impact of mirabegron extended-release on the treatment of overactive bladder with urge urinary incontinence, urgency, and frequency

Overactive bladder is a highly prevalent disorder with a significant impact on quality of life. Antimuscarinic agents are commonly used, but persistence is limited due to unsatisfactory efficacy and/or tolerability. Mirabegron is the first beta-3 adrenoceptor agonist approved for the treatment of overactive bladder syndrome. This paper reviews the pharmacology, mechanism of action, efficacy, and safety of mirabegron. A PubMed search of all English articles pertaining to mirabegron was performed. An alternative to antimuscarinics, mirabegron has a unique mechanism, improves overactive bladder symptoms and quality of life, and has limited adverse effects and few contraindications.