Current and Emerging Pharmacological Targets and Treatments of Urinary Incontinence and Related Disorders

β3-Adrenoceptor Agonist Effects on the Urinary Bladder Beyond Detrusor Relaxation

AIMS

β3-Adrenoceptor agonists such as mirabegron or vibegron reach pharmacokinetic steady-state within a few days. However, maximum improvements in symptoms of the overactive bladder syndrome are reached at time points later than 4 weeks, that is, detrusor smooth muscle relaxation cannot fully explain clinical effects. Therefore, we review mechanistic studies that have administered such drugs for longer periods of time.

METHODS

Narrative review.

RESULTS

The limited data indicates that β3-adrenoceptor agonists reduce bladder fibrosis and hypertrophy and may induce cell proliferation, and normalize increased apoptosis and ferroptosis. On the other hand, limited data also indicate that detrusor relaxation responses can partly desensitize with prolonged agonist exposure, possibly off-setting effects on fibrosis and hypertrophy.

CONCLUSIONS

Further long-term studies with β3-adrenoceptor agonists are needed to clarify the role of such processes in clinical improvement of patients with overactive bladder syndrome occurring at time points later than 4 weeks after initiation of treatment.

Comparative Efficacy and Safety of Mirabegron and Vibegron in Female Patients With Overactive Bladder: A Systematic Review and Meta-analysis of Randomized Controlled Trials

This meta-analysis compared mirabegron and vibegron efficacy/safety in female overactive bladder (OAB) patients, adhering to PRISMA guidelines (PROSPERO CRD42024587945). Pooling data from 3 RCTs (n=371), vibegron showed superior urgency urinary incontinence relief versus mirabegron (p=0.02), while demonstrating comparable OAB symptom scores, urgency episodes, quality of life, and voided volumes. Safety profiles were similar for total adverse events, constipation, post-void residuals, and dizziness. Both medications exhibit comparable overall efficacy and safety, though vibegron may offer specific advantages in managing incontinence symptoms.

Smooth muscle contractility of laser-enucleated prostate tissues and impacts of preoperative α1-blocker treatment in patients with and without catheterization

Prostate smooth muscle contraction is central in treatment of voiding symptoms in benign prostatic hyperplasia (BPH). Tissues from transurethral resection of the prostate (TURP) and radical prostatectomy (RP) for prostate cancer are widely used to study contractions. However, findings are limited by traumatization in TURP, and uncertain relationship to BPH in RP tissues. This study aims to examine contractions of laser-enucleated tissues. Tissues from holmium/thulium laser enucleation (HoLEP/ThuLEP) and TURP were contracted by KCl, noradrenaline and electric field stimulation (EFS) in an organ bath. Contractions were compared to RP tissues in previous studies. KCl-induced contractions averaged 2.5 mN, 0.7 mN and 3.3 mN in tissues from HoLEP/ThuLEP, TURP and RP, with non-responsive tissues included (2.4% HoLEP/ThuLEP, 37% TURP). Maximum EFS-induced contractions (Emax) averaged 47% of KCl in HoLEP/ThuLEP tissues, 27% in TURP tissues, and 68-235% in 21 previous studies with RP tissues. Emax values for noradrenaline averaged 99.7% in HoLEP/ThuLEP tissues, 56% in TURP tissues, and ranged from 92 to 260% in RP tissues. Preoperative α1-blocker treatment reduced EFS- and noradrenaline-induced contractions, and increased EC50 values for noradrenaline in laser-enucleated, catheterized patients, but not in patients without catheterization. Also, the ex vivo application of α1-blockers increased the EC50 values for noradrenaline and reduced Emax for EFS. Laser-enucleated tissues allow investigation of prostate smooth muscle contraction in medication-refractory voiding symptoms. Different impacts of preoperative α1-blocker treatment on ex vivo contractility in tissues from patients with and without catheterization point to clinically relevant heterogeneity of patients undergoing surgery for BPH.

Comparison of the 3-Year Continuation Rate and Discontinuation Factors Between Vibegron and Mirabegron in Patients With Overactive Bladder: A Retrospective Follow-Up Study in a Rehabilitation Hospital in Japan

OBJECTIVES

The objective of this study is to compare the 3-year continuation rate and discontinuation factors between vibegron and mirabegron in patients with overactive bladder in a rehabilitation hospital in Japan.

METHODS

The 3-year continuation rate of the target drugs and reasons for discontinuation as well as patients' backgrounds and adverse effects were evaluated retrospectively from the medical records between September 2018 and December 2020. After selecting patients according to our inclusion and exclusion criteria, 136 cases taking mirabegron and 82 taking vibegron were adjusted for intergroup variability by propensity score matching. We performed Cox proportional hazards regression for the 3-year continuation rate and Fine-Gray proportional hazards regression for the 3-year cumulative incidence of discontinuation events. Subgroup analysis was also performed.

RESULTS

Approximately 70% of the patients analyzed had neurogenic overactive bladder. The 3-year continuation rate was 65.2% in vibegron and 30.3% in mirabegron, and the hazard ratio was 0.41 (95% confidence interval: 0.25-0.68, p < 0.001) as for an incidence of discontinuation events of vibegron against mirabegron. The incidence of discontinuation due to inadequate efficacy was 22.7% in vibegron and 47.0% in mirabegron, and similarly the hazard ratio was 0.43 (95% confidence interval: 0.23-0.80, p < 0.01). In the subgroup analysis, vibegron continued significantly more than mirabegron for the 3-year continuation rate in non-neurogenic overactive bladder (p < 0.001), in spontaneous voiding (p < 0.001), in anticholinergic combination (p = 0.0017), in female (p < 0.001), and in 70 years or older (p = 0.0028). Additionally, a significant interaction was observed regarding the methods of emptying urine (p = 0.0066).

CONCLUSIONS

Vibegron was superior to mirabegron in the 3-year continuation rate of administration with a fewer discontinuation due to inadequate efficacy in a patient population with relatively high rates of neurogenic overactive bladder.

Polo-like kinase 1 inhibition modulates urinary tract smooth muscle contraction and bladder cell transcriptional programs

The serine/threonine kinase polo-like kinase 1 (PLK1) is a master regulator of cell proliferation and contraction, but its physiological role in the lower urinary tract is unknown. We utilized transcriptomic programs of human bladder smooth muscle cells (hBSMCs), 3D bladder spheroid viability assays, and human ureterovesical junction contractility measurements to elucidate the impacts of PLK1 inhibition. This work reveals PLK1 reduction with the selective inhibitor TAK-960 (500 nM) suppresses high K+-evoked contractions of human urinary smooth muscle ex vivo while decreasing urothelial cell viability. Transcriptomic analysis of hBSMCs treated with TAK-960 shows modulation of cell cycle and contraction pathways, specifically through altered expression of Cys2/His2-type zinc finger transcription factors. In bladder spheroids, PLK1 inhibition also suppresses smooth muscle contraction protein filamin. Taken together, these findings establish PLK1 is a critical governor of urinary smooth muscle contraction and urothelial proliferation with implications for lower urinary tract disorders. Targeting PLK1 pharmacologically may therefore offer therapeutic potential to ameliorate hypercontractility and aberrant growth. Further elucidation of PLK1 signaling networks promises new insights into pathogenesis and much needed treatment advances for debilitating urinary symptoms.

Efficacy and safety of gefapixant in women with chronic cough and cough-induced stress urinary incontinence: a phase 3b, randomised, multicentre, double-blind, placebo-controlled trial

BACKGROUND

Approximately two-thirds of women with chronic cough have cough-induced stress urinary incontinence (CSUI). We aimed to evaluate the efficacy and safety of gefapixant in reducing CSUI episodes in women with refractory or unexplained chronic cough.

METHODS

This phase 3b, double-blind, randomised, placebo-controlled trial done at 90 sites in 12 countries enrolled women aged 18 years or older who had chronic cough for at least 1 year, a diagnosis of refractory or unexplained chronic cough, a cough severity visual analogue scale score of 40 mm or more (100 mm maximum), and CSUI for 3 months or more. Participants were randomised 1:1 to oral gefapixant or placebo for 12 weeks. The primary outcome was percentage change from baseline in daily CSUI episodes (7-day average) at week 12. This study is registered with ClinicalTrials.gov (NCT04193176).

FINDINGS

From May 10, 2020, to Sept 2, 2022, 375 participants were randomised to and treated with gefapixant 45 mg twice daily (n=185) or placebo (n=190). Mean age was 56·4 years (SD 11·4), with mean chronic cough duration of 5·2 years (SD 6·6) and SUI duration of 4·0 years (SD 5·9). Least-squares mean percentage change from baseline in daily CSUI episodes was -52·8% (95% CI -58·4 to -47·1%) for gefapixant and -41·1% (-46·7 to -35·4%) for placebo (estimated treatment difference: -11·7% [95% CI -19·7 to -3·7]; p=0·004). 129 (70%) of 185 participants who received gefapixant and 71 (37%) of 190 participants who received placebo had at least one adverse event. Safety and tolerability were consistent with previous trials of gefapixant; the most frequent adverse events were taste related.

INTERPRETATION

Gefapixant 45 mg twice daily is the first treatment to show efficacy versus placebo in reducing CSUI episodes in participants with refractory or unexplained chronic cough.

FUNDING

Merck Sharp & Dohme, a subsidiary of Merck & Co.

Clinical research perspective on moxibustion treatment for urinary incontinence: A perspective review

This study provides an in-depth perspective of moxibustion as a treatment option for urinary incontinence (UI), focusing on its clinical efficacy, underlying mechanisms, and potential integration into standard care practices. Moxibustion, rooted in traditional Chinese medicine, involves the targeted application of heat from burning moxa at specific acupoints. Analyzing data from randomized controlled trials and retrospective studies, the study suggests that moxibustion effectively reduces UI symptoms and improves quality of life with minimal adverse effects. The therapeutic benefits are attributed to enhanced blood circulation, improved neurological functions, and hormonal balance, facilitating tissue repair, and urinary system functionality. Despite encouraging outcomes, existing research exhibits limitations, including small sample sizes, and inconsistent methodologies. Future research should aim to address these gaps by conducting larger, standardized multicenter trials to provide more definitive evidence of moxibustion's effectiveness. Additionally, integrating moxibustion into comprehensive treatment strategies for UI and promoting its inclusion in clinical guidelines could enhance its acceptance and application in modern medical practice. This study underscores the potential of moxibustion as a non-alternative in the management of UI, warranting further exploration and validation in clinical settings.

Efficacy and safety of intradetrusor abobotulinumtoxinA and incobotulinumtoxinA in women with overactive bladder and the value of local anesthesia: a randomized clinical study

BACKGROUND

A non-inferiority clinical study evaluated the efficacy and safety of abobotulinumtoxinA vs. incobotulinumtoxinA intradetrusor injections in women with overactive bladder and urge urinary incontinence. Also, the effect of local anesthesia on the pain level of the procedure was assessed.

METHODS

Patients were randomized to receive 20 intradetrusor injections of either 300 U abobotulinumtoxinA or 100 U incobotulinumtoxinA. They were further randomized to receive either local anesthesia (40 ml 1% lidocaine solution) or placebo before botulinum toxin injection. Before the procedure and 4 months after the procedure each patient reported urinary incontinence episodes, frequency, nocturia, completed the Urogenital Distress Inventory (UDI-6) score, Incontinence Impact Questionnaire (IIQ-7), and Incontinence Quality of Life (I-QOL) questionnaire. Each patient completed a patient satisfaction survey 4 months after the procedure. During the procedure, the patients graded the pain intensity of every injection on a visual analog scale (VAS). The total score of each questionnaire was considered.

RESULTS

A total of 54 patients with a mean age of 66 ± 13 (SD) years completed the study. Total scores of UDI‑6, IIQ‑7, I‑QOL, patient satisfaction, urinary incontinence episodes, frequency, nocturia and VAS questionnaires did not show differences between the abobotulinumtoxinA (n = 26) or incobotulinumtoxinA (n = 28) group. Urinary retention requiring catheterization was noted in five patients. The VAS and patient satisfaction questionnaire values did not show significant differences between the group receiving bladder instillation with lidocaine solution (n = 28) or the group receiving placebo (n = 26).

CONCLUSION

In women with overactive bladder and urge urinary incontinence where conservative treatment failed, abobotulinumtoxinA vs. incobotulinumtoxinA intradetrusor injections showed comparable results regarding improved clinical outcome and patient satisfaction. Local anesthesia before the procedure did not reduce the pain level in comparison with the placebo.

What is the best first choice oral drug therapy for OAB?

AIMS

The management of overactive bladder (OAB) involves lifestyle changes and conservative measures in the first instance with the use of liquid/dietary advice, weight loss, and bladder training. Thereafter oral pharmacotherapy is instigated in symptomatic patients. Antimuscarinics and beta 3 agonists form the main classes of drug therapy in this field. Views on what is the best first line OAB treatment is changing based on recent evidence and adverse event profiles of these medications.

METHODS

At the ICI-RS meeting 2023, Bristol, UK this topic was discussed and debated as a proposal. The following article summarizes the concepts presented that day as well as the interactive discussion that took place thereafter.

RESULTS

OAB guidelines are moving in many circumstances to an either antimuscarinic or beta 3 agonist approach based on patient factors. Several studies have raised concerns on the long-term impact of antimuscarinics, in relation to cognition, dementia, cardiovascular events, and mortality all related to antimuscarinic load. Neither antimuscarinics nor beta 3 agonists have good persistence and adherence rates in the medium to long term. Several barriers also exist to prescribing including guidelines recommending utilizing drugs with the lowest acquisition cost and "step therapy." A newer approach to managing OAB is personalized therapy in view of the many possible etiological factors and phenotypes. These concepts are highlighted in this article.

CONCLUSIONS

Current oral pharmacotherapy in managing OAB is limited by adverse events, adherence and persistence problems. Both antimuscarinics and beta 3 agonists are efficacious but most clinical trials demonstrate significant placebo effects in this field. Personalizing treatment to the individual seems a logical approach to OAB. There is a need for better treatments and further studies are required of existing treatments with high quality longer term outcomes.

Dynamic phenotypic shifts and M2 receptor downregulation in bladder smooth muscle cells induced by mirabegron

Introduction

Mirabegron is available for treatment of overactive bladder (OAB). However, mechanisms underlying symptom improvements and long-term effects on bladder smooth muscle cells are uncertain. Contractility and growth of bladder smooth muscle contribute to OAB, and depend on smooth muscle phenotypes, and on muscarinic receptor expression. Here, we examined prolonged exposure to mirabegron (20-48 h) on phenotype markers, muscarinic receptor expression, and phenotype-dependent functions in human bladder smooth muscle cells (hBSMC).

Methods

Expression of markers for contractile (calponin, MYH11) and proliferative (MYH10, vimentin) phenotypes, proliferation (Ki-67), and of muscarinic receptors were assessed by RT-PCR. Proliferation, viability, actin organization and contractions in cultured hBSMC were examined by EdU, CCK-8, phalloidin staining and matrix contraction assays.

Results

Calponin-1 mRNA decreased with 100 nM and 150 nM mirabegron applied for 20 h (0.56-0.6 fold of controls). Decreases were resistant to the β3-AR antagonist L-748,337 (0.34-0.55 fold, 100-150 nM, 20 h). After 40 h, decreases occured in the presence of L-748,337, but not without L-748,337. MYH11 mRNA increased with 150 nM mirabegron (40 h, 1.9 fold). This was partly preserved with L-748,337, but not observed after 20 h mirabegron exposure. Vimentin mRNA reduced with 150 nM mirabegron after 20 h, but not after 40 h, with and without L-748,337 (0.71-0.63 fold). MYH10 mRNA expression remained unaffected by mirabegron. Exposure to 150 nM mirabegron increased Ki-67 mRNA after 20 h in the presence of, but not without L-748,337, and after 40 h without, but not with L-748,337. Proliferation rates and actin organization were stable with 50-150 nM mirabegron (24 h, 48 h). Viability increased significantly after mirabegron exposure for 20 h, and by trend after 40 h, which was fully sensitive to L-748,337. M2 mRNA was reduced by 20 h mirabegron, which was resistant to L-748,337. Carbachol (3 µM) enhanced time-dependent contractions of hBSMC, which was inhibited by mirabegron (150 nM) in late phases (24 h), but not in early phases of contractions. Conclusion: Mirabegron induces dynamic phenotype alterations and M2 downregulation in hBSMC, which is paralleled by time-shifted anticontractile effects. Phenotype transitions may be involved in improvements of storage symptoms in OAB by mirabegron.

Ligand-Receptor Interactions and Structure-Function Relationships in Off-Target Binding of the β3-Adrenergic Agonist Mirabegron to α1A-Adrenergic Receptors

The β3-adrenoceptor agonist mirabegron is available for the treatment of storage symptoms of overactive bladder, including frequency, urgency, and incontinence. The off-target effects of mirabegron include binding to α1-adrenoceptors, which are central in the treatment of voiding symptoms. Here, we examined the structure-function relationships in the binding of mirabegron to a cryo-electron microscopy structure of α1A. The binding was simulated by docking mirabegron to a 3D structure of a human α1A-adrenoceptor (7YMH) using Autodock Vina. The simulations identified two binding states: slope orientation involving 10 positions and horizontal binding to the receptor surface involving 4 positions. No interactions occurred with positions constituting the α1A binding pocket, including Asp-106, Ser-188, or Phe-312, despite the positioning of the phenylethanolamine moiety in transmembrane regions close to the binding pocket by contact with Phe-288, -289, and Val-107. Contact with the unique positions of α1A included the transmembrane Met-292 during slope binding and exosite Phe-86 during horizontal binding. Exosite binding in slope orientation involved contact of the anilino part, rather than the aminothiazol end, to Ile-178, Ala-103, and Asn-179. In conclusion, contact with Met-292 and Phe-86, which are unique positions of α1A, accounts for mirabegron binding to α1A. Because of its lack of interactions with the binding pocket, mirabegron has lower affinity compared to α1A-blockers and no effects on voiding symptoms.

Pharmacotherapy in Stress Urinary Incontinence; A Literature Review

PURPOSE OF REVIEW

Stress urinary incontinence (SUI) is a commonly observed condition in females, as well as in males who have undergone prostatectomy. Despite the significant progress made in surgical techniques, pharmacotherapy has not yielded substantial outcomes within the clinical domain. This review aims to present a comprehensive overview of the existing pharmacotherapy options for stress urinary incontinence (SUI) and the emerging therapeutic targets in this field.

RECENT FINDINGS

One meta-analysis demonstrated that α-adrenergic medications are more efficacious in improving rather than curing SUI symptoms. One trial showed reduced pad weight gain with PSD-503, a locally administered α-adrenergic receptor agonist. New data show that duloxetine's risk outweighs its benefits. One small-scale trial was found to support the use of locally administered estriol in improving subjective outcomes. Emerging targets include serotonin 5HT2C agonists, selective inhibitors of norepinephrine uptake, and myostatin inhibitors. Only one of the evaluated drugs, duloxetine, has been approved by some countries. Currently, trials are evaluating novel targets. Systemic adverse effects such as gastrointestinal upset with duloxetine and orthostatic hypotension with α-adrenoceptor agonists have hampered the efficacy of drugs used to treat SUI in women and men.

Tibial Nerve Stimulation for Urge Urinary Incontinence and Overactive Bladder: Narrative Review of Randomized Controlled Trials and Applicability to Implantable Devices

The tibial nerve is an established target for neuromodulation in the management of overactive bladder (OAB) and its associated symptoms, including urge urinary incontinence (UUI). Technologies are currently available to deliver tibial nerve stimulation (TNS) through percutaneous devices or through implantable devices. The benefits and safety of percutaneous TNS have led to it as a guideline-recommended therapy. However, patient compliance is limited by the burden of weekly office visits and the need for maintenance treatments. Further, insurance often only covers a limited number of lifetime visits for percutaneous TNS. These factors and others have led to the development, study, and utilization of implantable TNS devices. Implantable TNS devices deliver the same therapeutic mechanism of action for nerve stimulation with a permanent implanted device that provides at-home stimulation rather than in-office therapy delivery. Additionally, there is an added potential for dynamic and patient-centered stimulation. There is a large body of high-quality evidence published for TNS, including numerous randomized controlled trials published on percutaneous TNS which have consistently demonstrated superior efficacy to sham and similar efficacy to that of anticholinergic medications. Percutaneous TNS also performs better than conservative therapy including pelvic floor muscle training. The percutaneous and implantable approaches deliver nerve stimulation to the same target nerve, using the same mechanism of action. Therefore, data from randomized trials of percutaneous TNS are informative for implantable TNS devices. At the time of this article's publication, at least two implantable TNS devices have received marketing authorization from the Food and Drug Administration (FDA). The objective of this review is to discuss the mechanism of action for TNS and summarize the published literature from clinical trials of percutaneous TNS as a foundation of high-quality evidence for implantable devices targeting the tibial nerve.

Promising therapeutic targets for the treatment of urine storage dysfunction: what's the status?

INTRODUCTION

Opinions differ on what drugs have both a rationale and a development potential for the treatment of bladder storage dysfunction.

AREAS COVERED

In the present review, the focus is given to small molecule blockers of TRP channels (TRPV1, TRPV4, TRPA1, and TRPM8), P2 × 3receptor antagonists, drugs against oxidative stress, antifibrosis agents, cyclic nucleotide - dependent pathways, and MaxiK±channel - gene therapy.

EXPERT OPINION

TRPV1 channel blockers produce hypothermia which seems to be a problem even with the most efficacious second-generation TRPV1 antagonists. This has so far precluded their application to urine storage disorders. Other TRP channel blockers with promising rationale have yet to be tested on the human lower urinary tract. The P2 × 3receptor antagonist, eliapixant, was tested in a randomized controlled clinical trial, was well tolerated but did not meet clinical efficacy endpoints. Antifibrosis agent still await application to the human lower urinary tract. New drug principles for oxidative stress, purine nucleoside phosphorylase inhibition, and NOX inhibition are still at an experimental stage, and so are soluble guanylate cyclase stimulators. Gene therapy with MaxiK±channels is still an interesting approach but no new trials seem to be in pipeline.

Effects of a proprietary mixture of extracts from Sabal serrulata fruits and Urtica dioica roots (WS® 1541) on prostate hyperplasia and inflammation in rats and human cells

Introduction: Phytotherapeutics, particularly extracts from Sabal serrulata (saw palmetto) fruit or Urtica dioica (stinging nettle) root, are popular for the treatment of male lower urinary symptoms in many countries, but their mechanism of action is poorly understood. We performed in vivo and in vitro studies to obtain deeper insight into the mechanism of action of WS® 1541, a proprietary combination of a Sabal serrulata fruit and an Urtica dioica root extract (WS® 1473 and WS® 1031, respectively) and its components. Methods: We used the sulpiride model of benign prostatic hyperplasia in rats and tested three doses of WS® 1541 in comparison to finasteride, evaluating weight of prostate and its individual lobes as well as aspects of inflammation, oxidative stress, growth and hyperplasia. In human BPH-1 cells, we studied the effect of WS® 1473, WS® 1031, WS® 1541 and finasteride on apoptosis, cell cycle progression and migrative capacity of the cells. Results: WS® 1541 did not reduce prostate size in sulpiride treated rats but attenuated the sulpiride-induced changes in expression of most analyzed genes and of oxidized proteins and abrogated the epithelial thickening. In vitro, WS® 1473 and WS® 1031 showed distinct profiles of favorable effects in BPH-1 cells including anti-oxidative, anti-proliferative and pro-apoptotic effects, as well as inhibiting epithelial-mesenchymal-transition. Conclusion: This data supports a beneficial effect of the clinically used WS® 1541 for the treatment of lower urinary tract symptoms associated with mild to moderate benign prostate syndrome and provides a scientific rationale for the combination of its components WS® 1473 and WS® 1031.

Comparison of mirabegron and vibegron for clinical efficacy and safety in female patients with overactive bladder: a multicenter prospective randomized crossover trial

PURPOSE

To compare the efficacy and safety of mirabegron and vibegron in female OAB patients.

METHODS

We conducted a multicenter, prospective, randomized crossover study of female patients with OAB. The patients were assigned to Group MV (mirabegron for 8 weeks, followed by vibegron for 8 weeks) or group VM (vibegron for 8 weeks, followed by mirabegron for 8 weeks). The primary endpoint was the change in OABSS from baseline, and the secondary endpoint was the change in FVC parameters. After completion of the study, each patient was asked which drug was preferable.

RESULTS

A total of 83 patients were enrolled (40 and 43 in groups MV and VM, respectively). At 8th and 16th week, 33 and 29 in Group MV and 34 and 27 in Group VM continued to receive the treatment. The change in PVR was not significantly different between treatment with mirabegron and vibegron. The changes in OABSS, nighttime frequency, mean, and maximum voided volume were similar between mirabegron and vibegron. The mean change in the daytime frequency was greater in the vibegron than in the mirabegron. Of the 56 patients, 15 (27%) and 30 (53%) preferred mirabegron and vibegron, respectively. The remaining 11 patients (20%) showed no preference. The change in the urgency incontinence score during vibegron was better in patients who preferred vibegron to mirabegron.

CONCLUSION

The efficacies of mirabegron and vibegron in female patients was similar. The patients' preference for vibegron could depend on the efficacy of vibegron for urgency incontinence.

Organ-specific off-target effects of Pim/ZIP kinase inhibitors suggest lack of contractile Pim kinase activity in prostate, bladder, and vascular smooth muscle

Smooth muscle contraction by Pim kinases and ZIPK has been suggested, but evidence for lower urinary tract organs or using Pim-selective inhibitor concentrations is not yet available. Here, we assessed effects of the Pim inhibitors AZD1208 and TCS PIM-1 and the dual ZIPK/Pim inhibitor HS38 on contractions of human prostate and bladder tissues and of porcine interlobar arteries. Human tissues were obtained from radical prostatectomy and radical cystectomy and renal interlobar arteries from pigs. Contractions were studied in an organ bath. Noradrenaline-, phenylephrine- and methoxamine-induced contractions were reduced (up to > 50%) with 500-nM AZD1208 in prostate tissues and to lesser degree and not consistently with all agonists in interlobar arteries. A total of 100-nM AZD1208 or 500-nM TCS PIM-1 did not affect agonist-induced contractions in prostate tissues. Decreases in agonist-induced contractions with 3-µM HS38 in prostate tissues and interlobar arteries were of small extent and did not occur with each agonist. Carbachol-induced contractions in detrusor tissues were unchanged with AZD1208 (500 nM) or HS38. Electric field stimulation-induced contractions were not affected with AZD1208 or HS38 in any tissue, but slightly reduced with 500-nM TCS PIM-1 in prostate tissues. Concentration-dependent effects of Pim inhibitors suggest lacking Pim-driven smooth muscle contraction in the prostate, bladder, and interlobar arteries but point to organ-specific functions of off-targets. Procontractile functions of ZIPK in the prostate and interlobar arteries may be limited and are lacking in the detrusor.

Adrenoceptors in the Lower Urinary Tract

Adrenoceptors importantly contribute to the physiological regulation of lower urinary tract (LUT) function and have become a target of several clinically successful treatments for major LUT diseases. In the bladder dome, β-adrenoceptor subtypes are found in multiple cell types and mediate relaxation of detrusor smooth muscle, perhaps partly indirectly by acting on afferent nerves and cells of the mucosa. β3-adrenoceptor agonists such as mirabegron and vibegron are used to treat overactive bladder syndrome. In the bladder trigone and urethra, α1-adrenoceptors cause contraction and thereby physiologically contribute to bladder outlet resistance. α1-adrenoceptors in the prostate also cause contraction and pathophysiologically elevate bladder outlet resistance leading to voiding dysfunction in benign prostatic hyperplasia. α1-adrenoceptor antagonist such as tamsulosin is widely used as a first-line option to treat LUT symptoms in men, but it remains unclear to which extent and how smooth muscle relaxation contributes to symptom relief.

Is the β3-Adrenoceptor a Valid Target for the Treatment of Obesity and/or Type 2 Diabetes?

β3-Adrenoceptors mediate several functions in rodents that could be beneficial for the treatment of obesity and type 2 diabetes. This includes promotion of insulin release from the pancreas, cellular glucose uptake, lipolysis, and thermogenesis in brown adipose tissue. In combination, they lead to a reduction of body weight in several rodent models including ob/ob mice and Zucker diabetic fatty rats. These findings stimulated drug development programs in various pharmaceutical companies, and at least nine β3-adrenoceptor agonists have been tested in clinical trials. However, all of these projects were discontinued due to the lack of clinically relevant changes in body weight. Following a concise historical account of discoveries leading to such drug development programs we discuss species differences that explain why β3-adrenoceptors are not a meaningful drug target for the treatment of obesity and type 2 diabetes in humans.

Efficacy of KPR-5714, a selective transient receptor potential melastatin 8 antagonist, on chronic psychological stress-induced bladder overactivity in male rats

AIMS

Chronic psychological stress aggravates lower urinary tract symptoms. Among others, water avoidance stress is a chronic psychological stressor that plays a causal role in the exacerbation and development of bladder dysfunction in rats. In this report, the effects of KPR-5714, which is a selective transient receptor potential melastatin 8 (TRPM8) antagonist, on bladder overactivity induced by water avoidance stress were examined.

METHODS

Male rats were subjected to water avoidance stress for 2 h per day for 10 consecutive days. The effects of water avoidance stress on voiding behavior using metabolic cages and histological bladder changes were investigated in rats. The involvement of bladder C-fiber afferent on voiding frequency in rats exposed to water avoidance stress was assessed using capsaicin. The effects of KPR-5714 on storage dysfunction in rats subjected to water avoidance stress were examined.

RESULTS

In voiding behavior measurements, water avoidance stress-induced storage dysfunction, causing a decrease in the mean voided volume and increasing voiding frequency. A comparison of bladders from normal rats and rats exposed to water avoidance stress showed no histological differences. Water avoidance stress-induced bladder overactivity was completely inhibited by pretreatment with capsaicin. KPR-5714 showed a tendency to increase the mean voided volume and significantly decreased the voiding frequency without affecting the total voided volume in these rats.

CONCLUSION

The results suggest that KPR-5714 is a promising option for treating chronic psychological stress-induced bladder overactivity.

Effect of bladder outlet procedures on urodynamic assessments in men with an acontractile or underactive detrusor: A systematic review and meta-analysis

OBJECTIVE

To review the effect of bladder outlet procedures on urodynamic outcomes and symptom scores in males with detrusor underactivity (DU) or acontractile detrusors (AD).

MATERIALS AND METHODS

We performed a systematic review and meta-analysis of research publications derived from PubMed, Embase, Web of Science, and Ovid Medline to identify clinical studies of adult men with non-neurogenic DU or AD who underwent any bladder outlet procedure. Outcomes comprised the detrusor pressure at maximum flow (Pdet Qmax ), maximum flow rate (Qmax ), international prostate symptom score (IPSS), and quality of life (QoL). This study is registered under PROSPERO CRD42020215832.

RESULTS

We included 13 studies of bladder outlet procedures, of which 6 reported decreased and 7 reported improved Pdet Qmax after the procedure. Meta-analysis revealed an increase in the pooled mean Pdet Qmax of 5.99 cmH2 0 after surgery (95% CI: 0.59-11.40; p = 0.03; I2 95%). Notably, the Pdet Qmax improved in all subgroups with a preoperative bladder contractility index (BCI) <50 and decreased in all subgroups with a BCI ≥50. All studies reported an improved Qmax after surgery, with a pooled mean difference of 5.87 mL/s (95% CI: 4.25-7.49; I2 93%). Only three studies reported QoL, but pooling suggested significant improvements after surgery (mean, -2.41 points; 95% CI: -2.81 to -2.01; p = 0.007). All seven studies reporting IPSS demonstrated improvement (mean, -12.82; 95% CI: -14.76 to -10.88; p < 0.001).

CONCLUSIONS

This review shows that Pdet Qmax and Qmax increases after surgical bladder outlet procedures in men with DU and AD. Bladder outlet procedures should be discussed as part of the shared decision-making process for this group. The evidence was of low to very low certainty.

Neuro-Urology and Biobanking: An Integrated Approach for Advancing Research and Improving Patient Care

Understanding the molecular mechanisms underlying neuro-urological disorders is crucial for the development of targeted therapeutic interventions. Through the establishment of comprehensive biobanks, researchers can collect and store various biological specimens, including urine, blood, tissue, and DNA samples, to study these mechanisms. In the context of neuro-urology, biobanking facilitates the identification of genetic variations, epigenetic modifications, and gene expression patterns associated with neurogenic lower urinary tract dysfunction. These conditions often present as symptoms of neurological diseases such as Alzheimer's disease, multiple sclerosis, Parkinson's disease, spinal cord injury, and many others. Biobanking of tissue specimens from such patients is essential to understand why these diseases cause the respective symptoms and what can be done to alleviate them. The utilization of high-throughput technologies, such as next-generation sequencing and gene expression profiling, enables researchers to explore the molecular landscape of these conditions in an unprecedented manner. The development of specific and reliable biomarkers resulting from these efforts may help in early detection, accurate diagnosis, and effective monitoring of neuro-urological conditions, leading to improved patient care and management. Furthermore, these biomarkers could potentially facilitate the monitoring of novel therapies currently under investigation in neuro-urological clinical trials. This comprehensive review explores the synergistic integration of neuro-urology and biobanking, with particular emphasis on the translation of biobanking approaches in molecular research in neuro-urology. We discuss the advantages of biobanking in neuro-urological studies, the types of specimens collected and their applications in translational research. Furthermore, we highlight the importance of standardization and quality assurance when collecting samples and discuss challenges that may compromise sample quality and impose limitations on their subsequent utilization. Finally, we give recommendations for sampling in multicenter studies, examine sustainability issues associated with biobanking, and provide future directions for this dynamic field.

Progress in Functional Urology Reflected in Recent Papers in the Journal of Clinical Medicine

Benign conditions of the lower urinary tract, including benign prostatic hyperplasia, overactive bladder syndrome, and stress urinary incontinence, are frequent in the general population. Despite their benign nature, they have major adverse effects on the quality of life of the afflicted patients and their partners. Despite major progress in the diagnosis and treatment of these conditions, improved understanding and management of these patients remain substantial medical needs. This editorial discusses some recent high-quality articles published in the Journal of Clinical Medicine on the understanding of the epidemiology, pathophysiology, diagnostic, and treatment of benign diseases of the lower urinary tract tissues such as the bladder and prostate.

Potential side effects of currently available pharmacotherapies in male lower urinary tract symptoms suggestive of benign prostatic hyperplasia

INTRODUCTION

The drug classes of α1-adrenoceptor antagonists, 5α-reductase inhibitors, and phosphodiesterase type 5 inhibitors are guideline-recommended treatments of lower urinary tract symptoms suggestive of benign prostatic hyperplasia; muscarinic receptor antagonists and β3-adrenoceptor agonists are also recommended if storage symptoms are insufficiently addressed with one of the other three drug classes.

AREAS COVERED

We provide a narrative review (no formalized literature searches performed) of the tolerability of these drug classes with emphasis on the more recently introduced medications, on combination treatment, and on more lately emerging risks.

EXPERT OPINION/COMMENTARY

The tolerability profiles are distinct between drug classes but, with few exceptions, similar within a drug class. Within a drug, formulations with longer duration of action tend to have better tolerability. Efficacy gains using combination treatment at least partly come at a cost of lesser tolerability. Greater susceptibility to experience adverse events based on age, comorbidities, and comedications appears conceptually important but remains under-investigated in this therapeutic area.

Sex and Gender Differences in the Pharmacology of the Overactive Urinary Bladder

Dysfunction of the lower urinary tract in general and the overactive bladder syndrome (OAB) in particular are prevalent and have major impact on the quality of life of the afflicted patients and their partners. We concisely review sex and gender differences in patients and animal models in physiological bladder function, its alterations in disease (mostly OAB), and its responses to treatment. Women appear to have a smaller functional bladder capacity and, therefore, must void more often than men. On the other hand, men have a greater bladder outlet resistance, which is partly attributed to a longer urethra and partly to the presence of the prostate. Sex and gender differences in bladder contractility appear small and were not found consistently. The ability of bladder smooth muscle to relax may be somewhat smaller in females. However, females are heavily underrepresented in experimental studies on bladder function. Stress urinary incontinence is found predominantly in women (particularly those after childbirth). OAB is similarly prevalent in men and women. Females seek treatment much more often and are overrepresented in clinical trials. Treatment responses in OAB patients are similar in both genders for oral medications, but improvements upon injections of onabotulinum toxin type A appear smaller in men. We conclude that there is no evidence for major sex and gender differences in bladder dysfunction as related to OAB and its treatment responses, but female animals are heavily underrepresented in experimental studies.