Efficacy and duration of response to botulinum neurotoxin A (onabotulinumA) as a treatment for detrusor overactivity in women

Real-world onabotulinumtoxinA treatment patterns in patients with overactive bladder

PURPOSE

Utilization patterns of third-line onabotulinumtoxinA for overactive bladder (OAB) symptoms-including discontinuation and use of other therapeutic options during or after treatment-are not well understood. This retrospective analysis of administrative claims was designed to characterize the unmet need for OAB treatment.

MATERIALS AND METHODS

A retrospective claims analysis of Optum's deidentified Clinformatics® Data Mart Database (2009-2021) was performed among patients with diagnosis of OAB newly starting onabotulinumtoxinA injection (2015-2017). Study measures were evaluated during an 18-month pretreatment baseline and over a minimum of 36 months of follow-up. These included number of injections, days between injections, other measures of onabotulinumtoxinA utilization, use of second-line pharmacologic treatments, use of device and surgical treatment options, and complications.

RESULTS

Of 2505 eligible patients, 535 (21.4%; 66.8 ± 13.3 y, 87.3% females) continued onabotulinumtoxinA throughout the study. The remaining 1970 (78.6%; 71.4 ± 11.6 y, 79.1% females) were considered discontinuers. Of continuers, 57% received ≥5 treatments. Of discontinuers, 84% received ≤2 treatments. Anticholinergics and β3-adrenoceptor agonist medication use declined in all patients from baseline to follow-up; however, the absolute reduction in the proportion with any medication fill was similar across continuers versus discontinuers (21% vs. 18%, p < 0.0001). Sacral neuromodulation was initiated by 15/535 (3%) of continuers and 137/1970 (7%) of discontinuers (p < 0.0001). No patients initiated percutaneous tibial neuromodulation.

CONCLUSIONS

Early discontinuation of onabotulinumtoxinA therapy for OAB is common and most discontinuers do not receive alternative treatments. Providers have the opportunity to educate OAB patients with un- or undertreated symptoms regarding alternative options.

Functional Polymorphism in the ADRB3 Gene, Encoding the Beta-3 Adrenergic Receptor, and Response to Intra-Detrusor Injection of Botulinum Toxin-A in Women with Overactive Bladder

BACKGROUND

There are reports suggesting an association between the rs4994 polymorphism in the ADRB3 gene encoding the beta-3 adrenergic receptor and OAB risk in females. The injection of botulinum toxin-A into the bladder wall is recommended as a possible treatment for OAB patients in whom first-line therapies have failed. The aim of our study was to analyze the possible association between the ADRB3:rs4994 polymorphism and the patient-perceived response to a single intra-detrusor injection of botulinum toxin-A in Polish women with overactive bladder.

METHODS

The study group consisted of 115 consecutive female patients with OAB. The response to botulinum toxin-A was evaluated at three months after injection, as absolute or relative reductions in OAB symptoms or in scores from questionnaires ICIQ-OAB (parts A and B) and ICIQ-LUTS-QoL (parts A and B). ADRB3:rs4994 variants were identified by the sequencing of genomic DNA extracted from buccal swabs.

RESULTS

There were no statistically significant differences between ADRB3:rs4994 [T];[T] homozygotes and [T];[C]+[C];[C] subjects for absolute or relative reductions in symptoms or in scores from all four questionnaire parts at three months after the injection of botulinum toxin-A.

CONCLUSIONS

Our results do not support the hypothesis that ADRB3:rs4994 polymorphism is associated with the response to the intra-detrusor injection of botulinum toxin-A in Polish females with overactive bladder.

Immunogenicity of Botulinum Toxin Formulations: Potential Therapeutic Implications

Botulinum neurotoxins (BoNTs) are proteins produced by bacteria of the Clostridium family. Upon oral ingestion, BoNT causes the neuroparalytic syndrome botulism. There are seven serotypes of BoNT (serotypes A-G); BoNT-A and BoNT-B are the botulinum toxin serotypes utilized for therapeutic applications. Treatment with BoNT injections is used to manage chronic medical conditions across multiple indications. As with other biologic drugs, immunogenicity after long-term treatment with BoNT formulations may occur, and repeated use can elicit antibody formation leading to clinical nonresponsiveness. Thus, approaching BoNT treatment of chronic conditions with therapeutic formulations that minimize stimulating the host immune response while balancing patient responsiveness to therapy is ideal. Immunogenicity is a clinical limitation in many settings that use biologic drugs for treatment, and clinically relevant immunogenicity reduction has been achieved through engineering smaller protein constructs and reducing unnecessary formulation components. A similar approach has influenced the evolution of BoNT formulations. Three BoNT-A products and one BoNT-B product have been approved by the Food and Drug Administration (FDA) for therapeutic use: onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, and rimabotulinumtoxinB; a fourth BoNT-A product, daxibotulinumtoxinA, is currently under regulatory review. Additionally, prabotulinumtoxinA is a BoNT-A product that has been approved for aesthetic indications but not therapeutic use. Here, we discuss the preclinical and clinical immunogenicity data that exist within the scientific literature and provide a perspective for considering immunogenicity as a key factor in choice of BoNT formulation.

Trigone as a diagnostic and therapeutic target for bladder-centric interstitial cystitis/bladder pain syndrome

The pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) may be bladder-centric, with afferent nerve hyperexcitability and/or due to neural central sensitization. In bladder-centric disease, the trigone's unmyelinated nociceptive C-fibers are thought to be upregulated, suggesting this as a potential target for diagnostic modalities and for treatment with local anesthetics and chemodenervation. We propose that the transvaginal trigone treatment (T3) route of administration of such treatments should be considered in women with IC/BPS, as this approach is easier and less invasive than cystoscopy. For T3, or other bladder-centric treatments to be successful, patient selection should attempt to exclude patients with predominantly neural central sensitization.

Outcomes of a single trigone-only vs. 20 trigone-sparing injections of OnabotulinumtoxinA for refractory overactive bladder (OAB)

PURPOSE

To compare the safety and durability of a single intravesical trigonal-only versus 20 trigone-sparing injections of OnabotulinumtoxinA (BTA) for refractory OAB.

METHODS

A chart review of all idiopathic OAB patients treated with BTA from January 2016 to December 2018 was performed. Outcomes measures included: inter-injection interval, post-void residual (PVR), urinary tract infections (UTI), urinary retention requiring catheterization, and procedure time (min). Statistical analyses were performed using independent sample t-tests.

RESULTS

Baseline characteristics were comparable for the two groups, data on 69 treatments (19 patients trigone-only) were compared to 105 treatments (26 patients trigone-sparing). There were no differences in the inter-injection intervals or rates of UTI. The trigone-only group exhibited a lower mean PVR (113 ml vs 160 ml, p < 0.02), lower proportion with PVR > 150 ml (23% vs. 39%, p < 0.03), lower rate of urinary retention (5.3% vs. 17.4%, p < 0.02), and shorter procedure time (4.3 min vs. 5.7 min, p < 0.01). There were no cases of vesico-ureteral reflux.

CONCLUSION

While interpretation remains speculative, the results of this observational study suggest that a single trigone-only injection appears to be as safe and durable as multiple trigone-sparing injections but maybe quicker to perform and appears to have a lower impact on voiding function. Larger series and adequately powered prospective randomized clinical trials are warranted to validate the findings of this pilot study.

Botulinum Toxin A: A Review of Potential Uses in Treatment of Female Urogenital and Pelvic Floor Disorders

Background: Botulinum toxin is an injectable neuromodulator that inhibits transmission between peripheral nerve endings and muscle fibers, resulting in muscle paralysis. Botulinum toxin type A is the most common form of botulinum toxin used in clinical practice.

Methods: In this review, we examine the mechanism of action, formulations, common clinical use in the genital-urinary tract, and potential clinical use in pelvic floor disorders of botulinum toxin type A.

Results: Several aspects of botulinum toxin A make it a favorable therapeutic tool, including its accessibility, its longevity, and its impermanence and reversibility of resultant chemodenervation in a relatively short and safe manner. Although botulinum toxin A has well-established efficacy in treating refractory overactive bladder and neurogenic detrusor overactivity, its use in pelvic floor disorders is still in its infancy.

Conclusion: The efficacy of botulinum toxin A for treating pelvic pain, voiding dysfunction, muscle pain and dysfunction, and certain colorectal-related pain issues shows promise but requires additional rigorous evaluation.

How long does the effect of botulinum toxin in neurogenic patients last? An analysis of the subset of "good responders"

BACKGROUND

The aim of this study was to assess long-term efficacity of botulinum neurotoxin A (BoNT-A) in the treatment of neurogenic detrusor overactivity (NDO).

MATERIALS AND METHODS

This was a retrospective monocentric study in a reference center. We included patients who received intradetrusor BoNT-A for NDO between 2001 and 2015. The focus of our analysis was on patients defined as "good responders" (≥ 5 injections of intradetrusor BoNT-A over a period of ≥5 years). The primary endpoint was the evaluation of long-term efficacity of BoNT-A. Recurrent NDO was monitored by the use of cystomanometry before the first injection and 1 month after each injection. The secondary objective was to assess the influence of NDO's etiology, age, and sex on the long-term efficacity of the treatment.

RESULTS

A total of 107 patients were included (60.7% with spinal cord injury [SCI] and 36.4% with multiple sclerosis [MS]). The mean follow-up period was 83.7 months (66; 120). The mean number of injections was of 8.9 (5; 21). A total of 67.3% (n = 72) of patients were still controlled by treatment at the end of their follow-up period. Therapeutic failure occurred in 30 patients (26.1%) with a cessation of BoNT-A treatment at 76 months on average (median: 82.5 months). There was no significant impact of age (P = .42), sex (P = .35), or NDO's etiology (MS vs SCI; P = .54) on long-term efficacy of BoNT-A treatment.

CONCLUSION

The results of our study indicate that the application of BoNT-A seems to be an effective and durable treatment in a large number of neurogenic patients after more than 10 years of follow-up. However, botulinum toxin tolerance occurred in approximately 25% of patients.

Assessment of Anticholinergic Use After Fading of BTX-A Effects in Refractory Idiopathic Overactive Bladder: A Prospective Blinded Randomized Trial

PURPOSE

To evaluate the efficacy and safety of re-treatment with anticholinergics on refractory idiopathic overactive bladder (OAB) previously treated with intravesical botulinum neurotoxin type A (BTX-A) injections.

METHODS

One hundred patients were initially managed by intravesical injections of 100 IU of BTX-A. After the effects of BTX-A faded, patients were randomized into 2 groups: group A patients received solifenacin (10 mg) for 12 weeks (study group), while group B patients received placebo treatment for 12 weeks (control group), then subsequently received solifenacin (10 mg) for another 6 weeks. All patients underwent preoperative urodynamic testing. Patients were asked to complete the validated overactive bladder symptoms score (OABSS) and incontinence quality of life (I-QoL) instruments after the effects of intravesical BTX-A faded and at 12 weeks of follow-up. Univariate and multivariate analyses of the factors affecting treatment response were conducted.

RESULTS

At 12 weeks of follow-up, in group A, all OABSS items, including the total score, had improved significantly (P<0.0001). Group A had lower frequency and amplitude of detrusor overactivity and detrusor leak point pressure (P<0.0001, P=0.03, and P=0.01, respectively). Cystometric capacity also increased significantly (P=0.007), as did all I-QoL parameters. In a comparison of patients with failed treatment and patients with successful treatment, female sex, repeated intravesical BTX-A injections, and increased bladder capacity were statistically significant (P=0.001, P=0.0001, and P=0.002, respectively). Repeated intravesical BTX-A injections and increased bladder capacity were independent factors predicting treatment success.

CONCLUSION

In patients with refractory idiopathic OAB, reuse of anticholinergics could be an effective treatment option in patients after the effects of BTX-A fade. Repeated intravesical BTX-A injections and increased cystometric capacity could affect treatment response.

Initial clinical experience with selective bladder denervation for refractory overactive bladder

Aims

To report the initial clinical experience with selective bladder denervation (SBD) of the trigone in women with refractory overactive bladder (OAB).

Methods

Females with refractory OAB underwent SBD of the bladder sub‐trigone region. Patients were treated using a 10‐s voltage‐controlled radiofrequency (RF) algorithm (RF10) at study onset. The protocol was modified during the study after which point remaining patients received 60‐s temperature‐controlled RF (RF60). Patients were followed for 12 weeks and evaluated for adverse events and changes in OAB symptoms. Exploratory analyses on the influence of RF duration were performed.

Results

Among 63 patients, SBD resulted in statistically significant and clinically important improvements for most outcomes. Comparing RF10 (n = 34) to RF60 (n = 29), treatment benefit was greater with RF60 including mean reduction in urgency urinary incontinence (−2.5 vs −0.9; P < 0.01), urinary incontinence (−2.6 vs −0.8; P < 0.001), and total urgency and frequency score (−13 vs −7; P = 0.02); and improvements in symptom bother (−33 vs −18; P < 0.01) and quality of life (28 vs 16; P = 0.02) on the OAB questionnaire. The proportion of urgency urinary incontinence treatment responders (≥50% reduction in episodes) was 79% with RF60 and 31% with RF10. The frequency of device‐ or procedure‐related adverse events was comparable in RF10 versus RF60 groups (14.7% vs 17.2%).

Conclusions

This study demonstrated the feasibility of SBD in alleviating symptoms of refractory OAB. A 60‐s RF algorithm using deeper ablations of the sub‐trigonal tissues was more effective and comparably safe to a 10‐s RF algorithm using more superficial ablations.

Neuropathic Bladder and Augmentation Cystoplasty

Surgical indications for individuals with neuropathic bladder include unsafe urinary storage pressures, progressive upper tract deterioration, and continued urinary incontinence that is recalcitrant to oral pharmacologic or intradetrusor injection therapy and intermittent catheterization. Bladder augmentation is currently the gold standard surgical procedure used to increase bladder capacity and reduce storage pressures but has significant long-term risks. The medical and surgical management of neuropathic bladder, as well as long-term consequences of bladder augmentation, are reviewed.

Safety issues associated with using medication to treat overactive bladder

INTRODUCTION

The mainstay of overactive bladder treatment is the use of anticholinergic medication with its common side effects well known. This review focused on three less well-known safety issues when treating OAB. Areas covered: Patients with increased anticholinergic load are at risk of cognitive decline, dementia or even death. The elderly are particularly at risk due to polypharmacy. Botulinum toxin carries the risk of high urinary residuals, urinary tract infection and need to self catheterise. The use of vaginal oestrogens may improve OAB symptoms, but there is concern in those with a history of breast cancer. Studies have shown that the systemic absorption is negligible and does not increase the risk of recurrence. Expert Opinion: Improvement in assessing anticholinergic load is needed with the development of a universal drug scale. To avoid increasing load, Mirabegron or botulinum toxin can be used instead. There is no consensus of the use of prophylactic antibiotics when injecting botulinum toxin and at what residual to initiate self catheterisation. Despite evidence showing that the use of vaginal oestrogens is safe in those with a history of cancer, it is not fully supported by any health body. Further work is needed in those using aromatase inhibitors.

Efficacy and safety of onabotulinumtoxinA injection in patients with refractory overactive bladder: First multicentric study in Turkish population

AIMS

To investigate the efficacy and safety of intradetrusor onabotulinumtoxinA (onaBoNT-A) injection in patients with overactive bladder (OAB) refractory to antimuscarinic treatment.

METHODS

A total of 80 patients with OAB symptoms were enrolled in this prospective multicenter study and received 100 U intradetrusor onaBoNT-A injection.The changes from baseline in the frequency of voiding, urge urinary incontinence (UI) and urge episodes, mean and maximum bladder capacities, uroflowmetry, post-void residual urine volume (PVR), quality of life score, and treatment benefit scale score were assessed. The need for a second injection,and treatment-related adverse events were also examined postoperatively.

RESULTS

OnaBoNT-A injection significantly decreased the UI episodes(P = 0.0001), the mean voiding frequency (P = 0.0001), and the urgency episodes (P = 0.0001) in the third month compared to baseline. Similarly, the mean bladder capacity, and maximal bladder capacity were increased (P < 0,05). The quality of life scores improved by 57.1% compared to the pre-treatment rate (P = 0,0001). No significant change was observed in the PVR or maximum flow rate. Urinary retention developed in 3 (3.75%) patients and urinary infection and transient hematuria were observed in five patients (6.25%) each. The UI episodes, voiding frequency and urgency episodes were significantly lower at the 9th month than at baseline (all P = 0.0001). Overall 67% of the patients continued to experience benefits from the injection. Sixteen patients (20%) required a second injection in the third month. Eight patients were lost to follow-up at the last visit in the 9th month, and 34 of the remaining 56 patients required a second injection at the 9th month. Cumulatively, 50 (63%) patients needed re-injections.

CONCLUSIONS

Our results demonstrated that the onaBoNT-A injection produced significant improvement in all OAB symptoms with a low incidence of treatment related adverse events.

Advancing a Comprehensive Approach to the Study of Lower Urinary Tract Symptoms

PURPOSE

Lower urinary tract symptoms are common in the United States population, leading to significant economic, quality of life and public health issues. The burden will increase as the population ages, and risk factors for lower urinary tract symptoms, including diabetes and obesity, remain highly prevalent. Improving clinical management and establishing the knowledge base to prevent lower urinary tract symptoms will require a comprehensive research approach that examines factors beyond the lower urinary tract. While the study of extra-lower urinary tract factors has increased recently, current urological research does not systematically account for the broad set of potential contributing factors spanning biological, behavioral, psychological/executive function and sociocultural factors. A comprehensive assessment of potential contributors to risk, treatment response and progression is necessary to reduce the burden of this condition in the United States.

MATERIALS AND METHODS

We considered challenges to continuing the predominantly lower urinary tract dysfunction centric approach that has dominated previous research of lower urinary tract symptoms.

RESULTS

We developed a new, comprehensive framework for urology research that includes a broader set of potential factors contributing to lower urinary tract symptoms. This framework aims to broaden research to consider a comprehensive set of potential contributing factors and to engage a broad range of researchers in the investigation of as many extra-lower urinary tract factors as possible, with the goal of improving clinical care and prevention.

CONCLUSIONS

We propose a new framework for future urology research, which should help to reduce the medical and economic burden of lower urinary tract symptoms in the United States population.