OnabotulinumtoxinA for the treatment of overactive bladder

Pilot Study of a Novel At-Home Posterior Tibial Nerve System for Overactive Bladder Syndrome

IMPORTANCE

Urgency urinary incontinence and overactive bladder are common conditions. Third-line therapies are often underutilized because of either being too invasive or being burdensome for the patient.

OBJECTIVE

We aimed to determine the efficacy and acceptability of a noninvasive, home-based posterior tibial nerve treatment system for the treatment of overactive bladder syndrome.

STUDY DESIGN

In this pilot study, 10 postmenopausal women with urgency urinary incontinence were given the SoleStim System for home-based posterior tibial nerve stimulation. Symptoms at baseline and completion of the 8-week study were determined by 3-day voiding diary and quality-of-life questionnaire (Overactive Bladder Questionnaire) to assess for reduction in incontinence episodes.

RESULTS

All patients were 100% adherent to the SoleStim System application over the 8-week period and reported statistically significant reductions in the mean number of voids (-16.3%, P = 0.022), urgency episodes (-31.2%, P = 0.02), and urgency urinary incontinence episodes (-31.4%, P = 0.045). Forty percent of participants reported a decrease of ≥50% in their urgency urinary incontinence episodes. SoleStim was scored a value of 1.8 ± 2.0 (mean ± SD) on a 10-point usability scale, indicating that it was highly acceptable from an ease-of-use perspective. No adverse events were reported.

CONCLUSIONS

The SoleStim System improved key overactive bladder (frequency, urgency, and urgency urinary incontinence episodes) and quality-of-life metrics. The results from this pilot study suggest that the SoleStim System may be a safe, effective, and highly acceptable at-home overactive bladder therapy.

Comparison of Two Treatment Modalities in Overactive Bladder: A Rapid Overview

Background

Overactive bladder is a syndrome of urgency with the absence of infection and is usually accompanied by frequency and nocturia. Both sacral neuromodulation (SNM) and intravesical botulinum toxin (BTX) injection are used contentiously in overactive bladder after failure of conservative management.

Objective

We aimed to provide an updated comparative overview of BTX injection versus SNM in the treatment of overactive bladder.

Methods

PubMed and Google scholar databases were explored starting from 2016 to 2022 to obtain relevant articles. English studies on adult population were included.

Results

Six articles included 648 participants were included in the current overview. Both BTX and SNM are comparable for the treatment of overactive bladder, with no major complications were reported. However, the use of SNM for refractory overactive bladder after failure of BTX was more successful and effective and resulted in patient satisfaction compared to the use of BTX after failure of SNM.

Conclusion

Our update provides the latest comparative overview of outcomes of BTX versus SNM in the treatment of overactive bladder.

Emerging Opportunities in Human Pluripotent Stem-Cells Based Assays to Explore the Diversity of Botulinum Neurotoxins as Future Therapeutics

Botulinum neurotoxins (BoNTs) are produced by Clostridium botulinum and are responsible for botulism, a fatal disorder of the nervous system mostly induced by food poisoning. Despite being one of the most potent families of poisonous substances, BoNTs are used for both aesthetic and therapeutic indications from cosmetic reduction of wrinkles to treatment of movement disorders. The increasing understanding of the biology of BoNTs and the availability of distinct toxin serotypes and subtypes offer the prospect of expanding the range of indications for these toxins. Engineering of BoNTs is considered to provide a new avenue for improving safety and clinical benefit from these neurotoxins. Robust, high-throughput, and cost-effective assays for BoNTs activity, yet highly relevant to the human physiology, have become indispensable for a successful translation of engineered BoNTs to the clinic. This review presents an emerging family of cell-based assays that take advantage of newly developed human pluripotent stem cells and neuronal function analyses technologies.

PGE2 receptors in detrusor muscle: Drugging the undruggable for urgency

Overactive bladder (OAB) syndrome is a prevalent condition of the lower urinary tract that causes symptoms, such as urinary frequency, urinary urgency, urge incontinence, and nocturia, and disproportionately affects women and the elderly. Current medications for OAB merely provide symptomatic relief with considerable limitations, as they are no more than moderately effective, not to mention that they may cause substantial adverse effects. Identifying novel molecular targets to facilitate the development of new medical therapies with higher efficacy and safety for OAB is in an urgent unmet need. Although the molecular mechanisms underlying the pathophysiology of OAB largely remain elusive and are likely multifactorial, mounting evidence from preclinical studies over the past decade reveals that the pro-inflammatory pathways engaging cyclooxygenases and their prostanoid products, particularly the prostaglandin E2 (PGE₂), may play essential roles in the progression of OAB. The goals of this review are to summarize recent progresses in our knowledge on the pathogenic roles of PGE₂ in the OAB and to provide new mechanistic insights into the signaling pathways transduced by its four G-protein-coupled receptors (GPCRs), i.e., EP1-EP4, in the overactive detrusor smooth muscle. We also discuss the feasibility of targeting these GPCRs as an emerging strategy to treat OAB with better therapeutic specificity than the current medications.

Alternative Methods for Testing Botulinum Toxin: Current Status and Future Perspectives

Botulinum toxins are neurotoxic modular proteins composed of a heavy chain and a light chain connected by a disulfide bond and are produced by Clostridium botulinum. Although lethally toxic, botulinum toxin in low doses is clinically effective in numerous medical conditions, including muscle spasticity, strabismus, hyperactive urinary bladder, excessive sweating, and migraine. Globally, several companies are now producing products containing botulinum toxin for medical and cosmetic purposes, including the reduction of facial wrinkles. To test the efficacy and toxicity of botulinum toxin, animal tests have been solely and widely used, resulting in the inevitable sacrifice of hundreds of animals. Hence, alternative methods are urgently required to replace animals in botulinum toxin testing. Here, the various alternative methods developed to test the toxicity and efficacy of botulinum toxins have been briefly reviewed and future perspectives have been detailed.

Application of methylene blue as an improvement of the injection technique of botulinum toxin A in the treatment of refractory idiopathic overactive bladder: prospective, single-blind (patient-blind), randomized trial

Introduction

Refractory idiopathic overactive bladder (RIOAB) is a common condition with a significant negative impact on quality of life. Intravesical injection of botulinum toxin A (BTX-A) is widely used as an intervention for these cases. In the standard method the drug solution is colorless. The addition of dye such as methylene blue (MB) facilitates visualization during the procedure and may have a beneficial effect.

Aim

To evaluate the injection of BTX-A with the addition of methylene blue (MB) against a standard method in the treatment of RIOAB.

Material and methods

In this 1-center, single-blinded, randomized controlled trial, we recruited 80 patients with RIOAB. A total of 39 were assigned to injection into the bladder wall of 100 U BTX-A with MB (in 9.5 ml normal saline + 0.5 ml MB), and 41 were assigned to BTX-A 100 U alone (in 10 ml normal saline). Cystoscopy with a submucosal injection of the solution was performed systematically, including the bladder triangle. Participants were assessed 6 and 12 weeks after the treatment using a Likert scale and OABSS questionnaire.

Results

Significant improvement was similar (result of 1 or 2 on the Likert scale) and was achieved in 66.7% and 69.2% after 6 weeks and in 63.9% and 64.1% after 12 weeks in the BTX-A + MB group and only-BTX-A group, respectively. There was a significant difference between the two groups (p = 0.049) in the total number of patients with complications: 2 (5.6%) vs. 9 (23.1%).

Conclusions

The addition of MB to BTX for treatment of RIOAB patients does not influence treatment efficacy, while it limits the risk of complications.

OnabotulinumtoxinA for the treatment of idiopathic overactive bladder is effective and safe for repeated use

INTRODUCTION

The objective of this study was to compare efficacy and safety outcomes between patients receiving onabotulinum-toxinA (OnabotA) for the first time and those receiving a repeat injection.

METHODS

Data collected before and after OnabotA injection were extracted from a clinical registry. Patients were classified into either first or repeat injection subgroups. Efficacy was measured by the change in use of oral bladder medications, the number of voids per day or night, the frequency of urinary incontinence (UI) episodes, and patient-reported outcomes. Safety was measured by the number of self-reported complications. Differences in safety measures between the subgroups were tested.

RESULTS

The analysis included complete data from 81 patients; 30 (37%) receiving OnabotA for the first time, 51 (63%) receiving a repeat injection. Both subgroups reported significant reductions in the use of anticholinergics, more tolerable bladder symptoms, and improvements in patient-reported outcomes. Dry rates were similarly high in both groups (50% and 43%, respectively). There were no statistically significant differences between the subgroups in terms of their safety outcomes.

CONCLUSIONS

OnabotA is equally as efficacious and safe for patients with overactive bladder receiving a repeat injection as it is for those receiving their first injection.

Adherence and persistence of mirabegron and anticholinergic therapies in patients with overactive bladder: a real-world claims data analysis

BACKGROUND

Adherence and persistence rates of anticholinergic (ACH) therapies have been well described. To date, few studies describe these metrics for mirabegron in patients with overactive bladder.

METHODS

This retrospective analysis of MarketScan® database assessed adherence and persistence of patients receiving either mirabegron or ACH. Study eligibility required an index date (first prescription filled) between July 2012 and June 2013 with 12 months of continuous enrolment preindex date and 12 months of follow-up. Adherence was defined as a proportion of days covered of ≥ 80% among patients with at least 2 fills of index medication. Persistence measures included treatment failure described as either treatment discontinuation (medication supply gap ≥ 30 days) or switching to a different medication. A medication supply gap of ≥ 45 days was used as a sensitivity analysis.

RESULTS

The mean age of mirabegron users (n = 4037) was 67 years and 43% were ACH naïve while the mean age of ACH users was 62 years (n = 67,943). Over the 12-month follow-up period, 44% of patients treated with mirabegron and 31% of patients treated with ACH were adherent to their indexed medications. Treatment failure was 81% for mirabegron and 88% for ACH. Most mirabegron treatment failures were because of treatment discontinuation (67%) versus switching to ACH therapy (14%). The ACH discontinuation rate was 84% and treatment switching rate was 4%. The mean (standard deviation) time to treatment failure was 143 (130) days for mirabegron and 69 (69) days for ACH. Adherence and persistence patterns were similar in the sensitivity analysis using a ≥ 45-day supply gap threshold.

CONCLUSIONS

This real-world study demonstrated low adherence and persistence to mirabegron similar to ACH therapies.

Intravesical OnabotulinumtoxinA Injection for Overactive Bladder Patients with Frailty, Medical Comorbidities or Prior Lower Urinary Tract Surgery

Overactive bladder (OAB) symptoms increase with age and involve several comorbidities. OnabotulinumtoxinA (BoNT-A) intravesical injection is a treatment choice for patients who are intolerant of or refractory to antimuscarinics. However, the increased risk of urinary tract infection and elevated post-void residual (PVR) volume post-treatment require resolution. Male sex, baseline PVR > 100 mL, and comorbidities are independent risk factors of adverse events (AEs) such as acute urinary retention (AUR). Intravesical BoNT-A injection is safe and effective for OAB patients with frailty, medical comorbidities such as Parkinson's disease (PD), chronic cerebrovascular accidents (CVA), dementia, or diabetes, or a history of prior lower urinary tract surgery (prostate or transvaginal sling surgery). Post-treatment, 60% of frail elderly patients had a PVR volume > 150 mL and 11% had AUR. Although intravesical BoNT-A injection is safe for PD patients, CVA patients had higher strain voiding rates. Diabetic patients were at increased risk of large PVR urine volume and general weakness post-treatment. Treatment results were similar between patients with and without a history of prostate or transvaginal sling surgery. Possible AEs and bladder management strategies should be conveyed to patients before treatment. Careful patient selection is important, and therapeutic safety and efficacy should be carefully balanced.

Practical Aspects of Botulinum Toxin-A Treatment in Patients With Overactive Bladder Syndrome

Intravesical onabotulinumtoxinA (BoNT-A) injection is an effective treatment for overactive bladder syndrome (OAB) that is refractory to antimuscarinics. An injectable dose of 100 U has been suggested to achieve the optimal balance of benefit and safety in patients with OAB. BoNT-A (total volume of 10 mL) was administered as evenly distributed intradetrusor injections (5 U) across 20 sites approximately 1 cm apart (0.5 mL per site) using a flexible or rigid cystoscope. Treatment with BoNT-A was generally well tolerated by most patients, and most treatment-related adverse events were localized to the urinary tract. The prevalence of OAB increases with age, and elderly patients are more vulnerable to complications. The short-term efficacy of intravesical BoNT-A injection for refractory OAB with no treatment-related complications in the elderly population has been documented. Frail elderly patients can experience the same treatment results, such as significantly improved urgent urinary incontinence and quality of life, as young and nonfrail elderly patients with 100-U BoNT-A injections. However, increased risk of larger postvoid residual (PVR) urine and lower long-term success rates were noted in frail elderly patients; around 11% had acute urinary retention, while 60% had PVR urine volume >150 mL after treatment. In addition, intravesical injection of BoNT-A effectively decreased urgency symptoms in elderly patients with OAB and central nervous system lesions. The adverse effects were acceptable, while the long-term effects were comparable to those in patients with OAB without central nervous system lesions. Nonetheless, the possibility of longstanding urinary retention and chronic catheterization in this vulnerable population requires careful evaluation before treatment with intravesical BoNT-A. In conclusion, the current findings indicate that intravesical BoNT-A is an effective and safe treatment for OAB in elderly patients.

Symptomatic management in multiple sclerosis

Multiple sclerosis (MS) is the commonest cause of disability in young adults. While there is increasing choice and better treatments available for delaying disease progression, there are still, very few, effective symptomatic treatments. For many patients such as those with primary progressive MS (PPMS) and those that inevitably become secondary progressive, symptom management is the only treatment available. MS related symptoms are complex, interrelated, and can be interdependent. It requires good understanding of the condition, a holistic multidisciplinary approach, and above all, patient education and empowerment.

Current and potential urological applications of botulinum toxin A

Botulinum toxin subtype A (BoNT-A) is a potent neurotoxin that can selectively modulate neurotransmitter release from nerve endings, resulting in muscular paralysis. BoNT-A might also act on sensory nerves, and have an anti-inflammatory effect. In the first urological use of BoNT-A, injection into the urethral sphincters of patients with detrusor-sphincter dyssynergia resulted in a reduction of urethral resistance and improved voiding efficiency. Subsequently, intravesical BoNT-A injections have received regulatory approval for treatment of neurogenic detrusor overactivity owing to spinal cord lesions or multiple sclerosis, and idiopathic overactive bladder in adults. BoNT-A has also been widely used to treat patients with the off-label indications of neurogenic or non-neurogenic voiding dysfunction and male lower urinary tract symptoms owing to BPH and bladder-neck dysfunction. Other indications for which urologists have applied BoNT-A injections include interstitial cystitis/bladder pain syndrome, bladder oversensitivity and chronic pelvic pain syndrome. BoNT-A is currently delivered as an intravesical injection; however, use of liposome encapsulated formulations is also beginning to show some therapeutic potential.