Intraprostatic botulinum toxin type “A” injection in patients with benign prostatic hyperplasia and unsatisfactory response to medical therapy: A randomized, double-blind, controlled trial using urodynamic evaluation

Clinical Application of Botulinum Neurotoxin in Lower-Urinary-Tract Diseases and Dysfunctions: Where Are We Now and What More Can We Do?

Botulinum toxin A (Botox) had been considered a promising drug that has an effect on functional disorders of the lower urinary tract. Because Botox exhibits anti-inflammatory and antispasmodic effects, Botox injection into the bladder can decrease detrusor contractility, reduce bladder hypersensitivity, and eliminate painful sensations. Injecting Botox into the bladder outlet can relax the hyperactivity of the bladder neck, and of the urethral smooth and striated muscles. Based on these therapeutic effects, Botox has been widely applied to treat lower-urinary-tract dysfunctions (LUTDs) such as overactive bladder and neurogenic detrusor overactivity. However, this treatment has not been licensed for use in other LUTDs such as interstitial cystitis, voiding dysfunction due to benign prostatic hyperplasia in men, and dysfunctional voiding in women. Botox has also not been approved for the treatment of children with overactive bladder and dysfunctional voiding; in patients with spinal cord injuries with detrusor sphincter dyssynergia and autonomic dysreflexia; or for poorly relaxed external sphincter in non-neurogenic patients. This article reviews the current knowledge regarding Botox treatment for LUTDs and discusses the potential clinical applications of Botox, as well as work that can be conducted in the future.

Transperineal intraprostatic injection of botulinum neurotoxin A vs transurethral resection of prostate for management of lower urinary tract symptoms secondary to benign prostate hyperplasia: A prospective randomised study

Objectives: To evaluate transperineal intraprostatic injection of botulinum neurotoxin A (BoNT-A) in patients with lower urinary tract symptoms (LUTS) secondary to benign prostate hyperplasia (BPH) who failed to respond to 6-month medical treatment compared with transurethral resection of the prostate (TURP).

Patients and methods: In all, 92 men were divided into TURP and BoNT-A groups after being evaluated using the International Prostate Symptom Score (IPSS) and five-item version of the International Index of Erectile Function, estimation of serum total prostate-specific antigen (tPSA), ultrasonographic estimation of prostatic volume (PV), and uroflowmetry determination of voiding volume (VV), maximum urinary flow rate (Q_max) and post-void residual urine volume (PVR). BoNT-A (200 U diluted in 3 mL saline) was injected, using a 22-G spinal needle under transrectal ultrasonography guidance, with 1-mL in each lobe. Patients were assessed 3-monthly for 12 months.

Results: The IPSS significantly decreased in all patients with a non-significant difference between the groups. The mean VV and Q_max increased, whilst PVR, PV and serum tPSA significantly decreased. Patients who showed deterioration at 12 months were re-evaluated and underwent TURP. BoNT-A injection significantly maintained erectile function compared with TURP.

Conclusion: Intraprostatic BoNT-A injection reduced PV with subsequent increases in VV and Q_max, and decreases in PVR and serum tPSA level. Intraprostatic BoNT-A injection allowed surgery sparing in >70% and preserved erectile function in 91.3% of patients.

Abbreviations: BoNT-A: botulinum neurotoxin A; HRQOL: health-related quality of life; IIEF-5: five-item version of the International Index of Erectile Function; PV: prostatic volume; PVR: post-void residual urine volume; Q_max: maximum urinary flow rate; tPSA: total PSA; VV: voided volume

Managing urinary incontinence in women - a review of new and emerging pharmacotherapy

INTRODUCTION

The pharmacological treatment of urinary incontinence and overactive bladder (OAB) has been, for a longer time, based on antimuscarinic agents. In recent years, two other pharmacological principles have been introduced for the treatment of OAB and urgency urinary incontinence: the β3-adrenergic agent mirabegron and botulinum neurotoxin. Meanwhile, there is lack of effective drugs for the treatment of stress incontinence.

AREAS COVERED

This literature review presents synthetic compounds aimed to treat female urinary incontinence that are in phase II-III clinical development.

EXPERT OPINION

Antimuscarinic agents will continue to represent the current gold standard for the first-line pharmacological management of OAB and urgency urinary incontinence. The class of β3-agonists will certainly expand with the discovery and clinical development of novel agents. Combination therapy of antimuscarinic agents and β3-agonists could offer an alternative treatment in these patients, including those with symptoms refractory to first-line monotherapy. A huge number of preclinical studies are underway in this field exploring the therapeutic potential of many novel compounds while some have advanced to clinical phases of development.

Novel Applications of OnabotulinumtoxinA in Lower Urinary Tract Dysfunction

OnabotulinumtoxinA (BoNT-A) was first used to treat neurogenic lower urinary tract dysfunction (LUTD) 30 years ago. Recently, application of BoNT-A in LUTD have become more common since the approval of intravesical BoNT-A injection for patients with both overactive bladders (OAB) and neurogenic detrusor overactivity (NDO) by regulatory agencies in many countries. Although unlicensed, BoNT-A has been recommended to treat patients with interstitial cystitis/bladder pain syndrome (IC/BPS) under different guidelines. BoNT-A delivery with liposome-encapsulation and gelation hydrogel intravesical instillation provided a potentially less invasive and more convenient form of application for patients with OAB or IC/BPS. BoNT-A injections into the urethral sphincter for spinal cord injury patients with detrusor-sphincter dyssynergia have been used for a long time. New evidence revealed that it could also be applied to patients with non-neurogenic dysfunctional voiding. Previous studies and meta-analyses suggest that BoNT-A injections for patients with benign prostate hyperplasia do not have a better therapeutic effect than placebo. However, new randomized and placebo-controlled trials revealed intraprostatic BoNT-A injection is superior to placebo in specific patients. A recent trial also showed intraprostatic BoNT-A injection could significantly reduce pain in patients with chronic prostatitis. Both careful selection of patients and prudent use of urodynamic evaluation results to confirm diagnoses are essential for successful outcomes of BoNT-A treatment for LUTD.

Lower Urinary Tract Symptoms: What's New in Medical Treatment?

CONTEXT

Pharmacological treatment is a cornerstone in the management of patients with lower urinary tract symptoms (LUTS).

OBJECTIVE

To review emerging evidence in the medical treatment of LUTS.

EVIDENCE ACQUISITION

An Embase/Pubmed-based literature search was conducted in December 2017, screening for randomized controlled trials (RCTs), prospective and retrospective series, animal model studies, and reviews on medical treatment of LUTS.

EVIDENCE SYNTHESIS

The main medical innovation in recent years in overactive bladder (OAB) has been the approval of the first β₃-adrenoceptor agonists (mirabegron) and intradetrusor onabotulinum toxin A, while several other drugs such as antiepileptics, phosphodiesterase inhibitors, or other β₃-agonists have brought promising results in phase 3 trials. Intraprostatic injections of various drugs for LUTS/benign prostatic hyperplasia have been investigated, but results of phase 3 trials are still pending, while combination therapies of phosphodiesterase type 5 inhibitors+α-blockers or finasteride have been proved as superior to single therapies in RCTs conducted in these patients. Two new formulations of desmopressin have been approved for nocturia in the USA (desmopressin nasal spray) and Europe/Canada/Australia (desmopressin orally disintegrated tablet). Fedovapagon, a vasopressin V₂ receptor agonist, has recently completed a large phase 3 trial in male patients with nocturia. Other phase 3 trials are ongoing in bladder pain syndrome (AQX 11-25, a SHIP-1 activator) and in neurogenic detrusor overactivity (mirabegron and abobotulinum toxin A).

CONCLUSIONS

Medical treatment of LUTS is a very active research field with recently approved drugs for nocturia (desmopressin acetate nasal spray/orally disintegrated tablet) and numerous emerging drugs currently investigated in OAB, LUTS/benign prostatic hyperplasia, nocturia, bladder pain syndrome, and neurogenic detrusor overactivity.

PATIENT SUMMARY

Medical treatment of lower urinary tract symptoms is a very active research field with recently approved drugs for nocturia (desmopressin acetate nasal spray/orally disintegrated tablet) and numerous emerging drugs in overactive bladder, nocturia, neurogenic detrusor overactivity, bladder pain syndrome, or benign prostatic hyperplasia.