Intravesical oxybutynin for treating incontinence resulting from an overactive detrusor

Open Label, Pilot Evaluation of the Safety and Efficacy of Intravesical Sustained Release System of Lidocaine and Oxybutynin (TRG-100) for Patients With Interstitial Cystitis/Bladder Pain Syndrome, Overactive Bladder and Patients With Retained Ureteral Stents Following Endourological Interventions

BACKGROUND

Intravesical instillation of analgesic and anticholinergic drugs have shown efficacy in the treatment of pain and voiding symptoms. Unfortunately, drug loss with urination and dilution in the bladder limit their durability and clinical usefulness. We have recently developed and tested in vitro, a sustained delivery system (TRG-100) of fixed-dose combination of lidocaine and oxybutynin designed to allow for a longer exposure of the urinary bladder to the drugs.

OBJECTIVE

To asses the safety and efficacy of TRG-100 in Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS), overactive bladder (OAB), and endourological intervention stented (EUI) patients in an open-label, prospective study.

METHODS

Thirty-six patients were enrolled: 10 IC/BPS, 10 OAB, and 16 EUI. EUI patients received a once-weekly installation until stent removal, OAB and IC/BPS patient received weekly installations for 4 consecutive weeks. Treatment effect was assessed by visual analog scale (VAS) score for the EUI group, voiding diaries for OAB group and VAS score, voiding diaries and O'Leary Sant Questionnaires for the IC/BPS group.

RESULTS

The EUI group showed a mean 4-point improvement in their VAS score. The OAB group showed 33.54% reduction in frequency of urination and IC/PBS group showed a mean of 3.2-point improvement in their VAS score, 25.43% reduction in frequency of urination, and a mean 8.1-point reduction in O'Leary Sant Questionnaires score. All changes were statistically significant.

CONCLUSION

Intravesical instillation of TRG-100 was found to be safe and efficient in reducing pain and irritative bladder symptoms in our study population. TRG-100 efficacy and safety should be further assessed in a large, randomized control trial.

Intravesical sustained release system of lidocaine and oxybutynin results from in vitro and animal study

PURPOSE

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic debilitating condition of unknown etiology. Intravesical lidocaine demonstrated pain relief in patients with IC/BPS. Intravesical oxybutynin has shown therapeutic efficacy in patients with urinary bladder disorders. However, loss of drug with urination requiring multiple administrations and immediate dilution of drug concentration by residual urine in the bladder mitigated intravesical use of both drugs in clinical practice. The aim of this study was to evaluate the efficacy and safety of fixed-dose combination of lidocaine and oxybutynin, forming in the urine a sustained delivery system named TRG-042.

MATERIAL AND METHODS

In-vitro, we have quantitatively tested the concentration of lidocaine and oxybutynin released from TRG-042 in artificial urine. Following the successful in-vitro study weekly formulation of TRG-042 was instilled intravesically to six pigs. All pigs were followed with cystoscopy to assess the gradual degradation of the delivery system and to evaluate bladder response over 7 days. Daily blood samples were tested for drug quantization.

RESULTS

In-vitro studies have demonstrated oxybutynin and lidocaine sustained release over 1-week period coupled with full degradation of the matrix. None of the animals demonstrated any side effects following instillation. Cystoscopy examination observed gradual disintegration of TRG-042 over 1-week with no adverse reaction to the mucosa. Plasma concentrations of oxybutynin and lidocaine were uniformly stable over the 1-week period [1.46 ± 0.176 ng/ml and 4.29 ± 2.48 ng/ml respectively(mean ± SEM)] with almost undetectable concentration of N-desethyloxybutynin (NDO)[0.032 ± 0.068 ng/ml].

CONCLUSIONS

The in-vitro and animal data demonstrated that TRG-042 can safely be used for intravesical sustained release of lidocaine and oxybutynin in the treatment of BPS/IC.

Current pharmacotherapy of overactive bladder

Overactive bladder is a symptom complex consisting of bothersome storage urinary symptoms that is highly prevalent among both sexes and has a significant impact on quality of life. Various antimuscarinic agents and the beta-3 agonists mirabegron and vibegron are currently available for the treatment of OAB. Each drug has specific pharmacologic properties, dosing schedule and tolerability profile, making it essential to individualize the medical treatment for the patient's characteristics and expectations. In this manuscript, we review the most important factors involved in the contemporary pharmacological treatment of OAB.

Intravesical gentamicin instillation for the treatment and prevention of urinary tract infections in complex paediatric urology patients: evidence for safety and efficacy

BACKGROUND

Little has been reported to date on the instillation of antimicrobials directly into the bladder in children. Children with complex urinary tract anomalies struggle frequently with recurrent urinary tract infections (UTI), with frequent emergence of antibiotic resistance. Gentamicin bladder instillation to treat and prevent UTI was described in children since 2006.

OBJECTIVE

We adopted gentamicin bladder instillation in 2016 and evaluate herein our intermediate-term experience with it.

STUDY DESIGN AND METHODS

This study is a retrospective review of a prospectively initiated database and a clinical audit of our practice. The gentamicin bladder instillation was employed in 24 cases. A treatment regime was initiated for symptomatic documented UTI when resistance patterns precluded an oral alternative (14 cases), avoiding hospitalisation for parenteral antibiotics. A prophylaxis regime (19 cases-including 9 of the 14 who received an initial treatment regime) followed at least one breakthrough UTI while receiving oral prophylactic antibiotics. Two instillation volumes (8 mg gentamicin in 20 mL 0.9% NaCl or 20 mg gentamicin in 50 mL 0.9% NaCl) were used to suit different bladder capacities. The irrigation is given twice a day for 7 days in the treatment regime or once a day, every other day, in the prophylactic regime. Gentamicin serum levels (all cases) and audiology/audiometry testing (17/24 cases) were checked to assess the safety of this method.

RESULTS

The median age when either the treatment course or prophylaxis regime was started was 3.8 years. The treatment regime was 86% successful (12/14) to suppress an acute UTI. The mean duration of prophylaxis was 252 days (median: 256 days). The percentage of patients on the prophylactic regime who had no breakthrough UTI was 58%. No serum gentamicin was detectable secondary to the intravesical instillation. No attributable cases of sensorineural hearing loss were detected. Gentamicin resistance emerged in one case (4.16%).

DISCUSSION

Intravesical administration was feasible via various routes for a spectrum of complex lower urinary tract abnormalities (see Summary Figure). Concerns regarding systemic absorption, nephrotoxicity or ototoxicity were investigated and safety ensured. Limitations include being a small series of non-identical pathologies, albeit categorically similar and being a single-arm study, however, statistical significance was proven descriptively and analytically.

CONCLUSION

In selected cases and with the appropriate specialist support and logistics, intravesical gentamicin instillation is well-tolerated and safe to treat and/or prevent urinary tract infections in pateints with complex bladder conditions and lower urinary tract pathologies.

Influence of urothelial or suburothelial cholinergic receptors on bladder reflexes in chronic spinal cord injured cats

The effects of intravesical administration of a muscarinic receptor agonist (oxotremorine-M, OXO-M) and antagonist (atropine methyl nitrate, AMN) and of a nicotinic receptor agonist (nicotine) and antagonist (hexamethonium, C₆) on reflex bladder activity were investigated in conscious female chronic spinal cord injured (SCI) cats using cystometry. OXO-M (50μM) decreased bladder capacity (BC) for triggering micturition contractions, increased maximal micturition pressure (MMP), increased frequency and area under the curve of pre-micturition contractions (PMC-AUC). Nicotine (250μM) decreased BC, increased MMP, but did not alter PMC-AUC. The effects of OXO-M on BC and PMC-AUC were suppressed by intravesical administration of AMN (50-100μM), and the effects of nicotine were blocked by hexamethonium (1mM). Antagonists infused intravesically alone did not alter reflex bladder activity. However, AMN (0.2mg/kg, subcutaneously) decreased PMC-AUC. 8-OH-DPAT (0.5mg/kg, s.c.), a 5-HT_1A receptor agonist, suppressed the OXO-M-induced decrease in BC but not the enhancement of PMC-AUC. These results indicate that activation of cholinergic receptors located near the lumenal surface of the bladder modulates two types of reflex bladder activity (i.e., micturition and pre-micturition contractions). The effects may be mediated by activation of receptors on suburothelial afferent nerves or receptors on urothelial cells which release transmitters that can in turn alter afferent excitability. The selective action of nicotine on BC, while OXO-M affects both BC and PMC-AUC, suggests that micturition reflexes and PMCs are activated by different populations of afferent nerves. The selective suppression of the OXO-M effect on BC by 8-OH-DPAT without altering the effect on PMCs supports this hypothesis. The failure of intravesical administration of either AMN or hexamethonium alone to alter bladder activity indicates that cholinergic receptors located near the lumenal surface do not tonically regulate bladder reflex mechanisms in the SCI cat.

Implantable Devices for Sustained, Intravesical Drug Delivery

In clinical settings, intravesical instillation of a drug bolus is often performed for the treatment of bladder diseases. However, it requires repeated instillations to extend drug efficacy, which may result in poor patient compliance. To alleviate this challenge, implantable devices have been developed for the purpose of sustained, intravesical drug delivery. In this review, we briefly summarize the current trend in the development of intravesical drug-delivery devices. We also introduce the most recently developed devices with strong potential for intravesical drug-delivery applications.

Investigating detrusor muscle concentrations of oxybutynin after intravesical delivery in an ex vivo porcine model

Intravesical oxybutynin is highly effective in the treatment of overactive bladder. Traditionally the mechanism of action was explained by antagonism of muscarinic receptors located in the detrusor, however evidence now suggests antimuscarinics may elicit their effect by modifying afferent pathways in the mucosal region. This study aimed to investigate the bladder wall distribution of oxybutynin in an ex vivo setting providing tissue - layer specific concentrations of drug achieved after intravesical delivery. Whole ex vivo porcine bladders were intravesically instilled with 0.167 mg mL(-1) oxybutynin solution. After 60 min, tissue samples were excised, serially sectioned parallel to the urothelial surface and extracted drug quantified. Drug distribution into the urothelium, lamina propria and detrusor was determined. Oxybutynin permeated into the bladder wall at a higher rate than other drugs previously investigated (apparent transurothelial Kp = 1.36 × 10(-5) cm s(-1) ). After 60 min intravesical instillation, concentrations achieved in the urothelium (298.69 μg g(-1) ) and lamina propria (43.65 μg g(-1) ) but not the detrusor (0.93 μg g(-1) ) were greater than reported IC50 values for oxybutynin. This work adds to the increasing body of evidence suggesting antimuscarinics elicit their effects via mechanisms other than direct inhibition of detrusor contraction.

Role of fesoterodine in the treatment of overactive bladder

Muscarinic receptors have long been the target receptors for treatment of patients with overactive bladder (OAB). These patients experience symptoms of urgency, urinary frequency and nocturia, with or without urge incontinence (the involuntary leakage of urine associated with urge). Fesoterodine, a pro-drug, structurally and functionally related to tolterodine, is the newest agent developed for the treatment of OAB. Fesoterodine is broken down to the active metabolite, 5-hydroxy-methyl-tolterodine (5-HMT) by non-specific esterases. This metabolism results in the complete breakdown of the parent compound and is responsible for dose related improvements in clinical efficacy and health related quality of life. Like other antimuscarinic agents including tolterodine, fesoterodine is associated with improvements in clinical variables related both to bladder filling (decreasing micturition frequency and increasing mean voided volume) and urgency (urgency and urge incontinence episodes). Improvements in health related quality of life following treatment with fesoterodine is indicated by improvements in 7 of the 9 variables measured by the King’s Health Questionnaire. Also like other antimuscarinic agents, fesoterodine use is associated with adverse events including dry mouth. However the incidence of dry mouth is reduced with fesoterodine, compared to oxybutynin, due to the improved bladder selectivity of 5-HMT.

Intravesical oxybutynin for children with poorly compliant neurogenic bladder: a systematic review

PURPOSE

Children with neurogenic bladder and poor bladder compliance are usually treated with bladder catheterization and oral anticholinergic medication. They may become nonresponders to the drug or present with severe side effects. We evaluated the effectiveness and tolerability of intravesical oxybutynin in children with poorly compliant neurogenic bladder.

MATERIALS AND METHODS

We conducted a search of MEDLINE, EMBASE, CINAHL, SciELO, dissertations/theses in ProQuest, LILACS, the Cochrane Library, protocol registries and the gray literature. Two reviewers independently assessed study quality and extracted data.

RESULTS

Eight studies (2 prospective, 6 retrospective) assessed the effectiveness and side effects of intravesical oxybutynin in children with neurogenic bladder. A total of 297 children started treatment, of whom 22% (66 patients) discontinued therapy, with 9% (28) quitting due to systemic side effects. Mean change in bladder compliance (primary outcome) was reported in only 2 studies (+7.4 and +7.5 ml/cm H(2)O). The pooled mean change in pressure at maximum bladder capacity was -16.4 cm H(2)O (95% CI -22.8 to -10.0). Incontinence improved significantly in most studies, with "dry and improved" rates ranging from 61% to 83%. The funnel plot of pressure at maximum bladder capacity suggested no publication bias.

CONCLUSIONS

Adjunctive intravesical oxybutynin therapy increased mean maximum bladder capacity and decreased bladder pressure in children with neurogenic bladder. However, identified studies offered a low level of evidence, with most being poorly reported retrospective case series with potential biases. Although the incidence of side effects was lower with the intravesical route, side effects are still possible and should be discussed with patients and families. The evidence available is insufficient to recommend this therapy. Research of more sound study design such as a randomized controlled trial should be conducted to assess the efficacy and side effects of intravesical oxybutynin in children.

Local Effects of Antimuscarinics

Overactive bladder (OAB) syndrome has been estimated to occur in nearly 17% of the population. The most common drug treatments for OAB are antimuscarinic agents that act to increase bladder capacity and decrease the urge to urinate during the storage phase. An increasing number of studies have focused on te role and mechanism of muscarinic acetylcholine receptors for the regulation of afferent activity during urine storage. Interactions between muscarinic receptors in the urothelium, afferent nerves, or myofibroblasts and locally released acetylcholine might be involved in the emergence of detrusor overactivity and OAB. Therefore, antimuscarinic agents may be effective in treating OAB not only by suppression of muscarinic receptor-mediated detrusor muscle contractions but also by modulation of muscarinic receptor-bladder afferent interactions.

Antimuscarinic drugs for the treatment of female urinary incontinence

Overactive bladder syndrome, urge syndrome or urgency-frequency syndrome is defined as 'urgency with or without urge incontinence, usually with frequency and nocturia'. Although this definition indicates that these symptoms are suggestive of detrusor overactivity (the observation of involuntary detrusor contractions during the filling phase of cystometry), a urodynamic demonstration of detrusor overactivity is not necessary in order to make the diagnosis. Nevertheless, patients with overactive bladder syndrome represent a substantial proportion of patients suffering with urinary symptomatology, and approximately a third of individuals with overactive bladder suffer from incontinence. Furthermore, as compared with those patients with stress urinary incontinence, women with urge incontinence have a poorer overall quality of life, perhaps related to both the volume of urine lost as well as the unpredictable nature of the leakage. When combined with behavioral modification, antimuscarinic pharmacotherapy remains the mainstay of treatment for this condition. A number of these agents are available for the treatment of overactive bladder-related incontinence, each with unique pharmacokinetic and pharmacodynamic properties. In order to optimize therapy for patients suffering from this type of incontinence, it is necessary to understand the mechanism of action of these agents, as well as to be familiar with the differences between them with respect to efficacy, safety and tolerability.

ABSORPTION OF INTRAVESICALLY APPLIED DRUGS: COMPARISON OF NORMAL AND ILEAL AUGMENTED RABBIT BLADDER

PURPOSE

Drug absorption within urinary diversions has been reported to cause prolonged and higher grade toxicity. Therefore, continuous urine drainage has been recommended during chemotherapy in patients with continent urinary diversion. We developed an animal model in which to examine the significance of drug absorption in normal rabbit bladders compared with ileal augmented bladders.

MATERIALS AND METHODS

Ten rabbits with ileal bladder augmentation and 5 control animals were used for absorption studies with methotrexate and ofloxacin. One, 4 and 12 months after surgery the rabbits received an intravesical instillation of either drug. During 2 hours blood samples were drawn. To avoid overfilling the bladder by urine it was emptied after 30, 60, 90 and 120 minutes, and refilled with fresh solution to yield a relatively constant drug amount. After 12 months the animals were sacrificed. Area of the native bladder wall and of the intestinal segment was measured to allow the correction of absorbed drug amounts per surface area. Moreover, the median villous heights of native and augmented ileum were compared histologically. Serum levels of methotrexate and ofloxacin were determined by high performance liquid chromatography.

RESULTS

The maximum serum concentration of the 2 drugs was typically seen after 60 to 120 minutes. During the 1-year period peak serum concentrations of ofloxacin remained consistently higher in ileal augmented than in control rabbits, although this did not achieve statistical significance at all instillation time points. For methotrexate a statistically significant difference was not shown for either time point. When absorption was corrected for total bladder surface area, the enhancement of ofloxacin absorption by ileal augmentation weakened and attained statistical significance only at the 1-month time point. Histological examinations after 12 months showed that augmented intestinal mucosa had a significantly smaller villous height than native ileum.

CONCLUSIONS

Our data demonstrate that bladder surface is the most important factor for increased absorption but time dependent histological changes of the integrated intestinal mucosa also influence absorption. There is a broad interindividual discrepancy. Therefore, general rules in patients with urinary diversion may not be justified.

Second Prize: Double-Blind Randomized Controlled Trial Assessing the Safety and Efficacy of Intravesical Agents for Ureteral Stent Symptoms after Extracorporeal Shockwave Lithotripsy

BACKGROUND AND PURPOSE

Ureteral stents are a significant source of pain and discomfort for many urologic patients. A novel approach to addressing this problem is the intravesical instillation of a selected pharmacologic agent after stent insertion. The purpose of this study was to assess the safety and efficacy of intravesical instillation of various agents in reducing ureteral stent-associated discomfort in patients requiring a stent after extracorporeal shockwave lithotripsy (SWL).

PATIENTS AND METHODS

In this double-blind prospective trial, 42 patients were randomized to receive intravesical instillation of one of three agents (oxybutynin, alkalinized lidocaine, or ketorolac) or a control solution (0.9% sodium chloride) immediately after stent insertion at time of SWL. The four groups of patients were demographically similar. Preoperative, intraoperative, and postoperative data were collected prospectively and analyzed statistically. The primary outcome measure was reduction in ureteral stent symptoms, and the secondary outcome measure was the safety of intravesical instillation of each agent through assessment of drug-related adverse events.

RESULTS

There were no intraoperative or postoperative complications, nor were there any serious side effects attributable to any of the intravesically instilled agents. There was a statistically significant decrease in stent-related discomfort at the 1-hour time point in the group of patients who received intravesical ketorolac compared with the control group.

CONCLUSIONS

Intravesical instillation represents a novel approach to the problem of ureteral stent-related discomfort. From our results, ketorolac appears to be the most effective intravesical agent in reducing stent-related patient discomfort, and we have established that intravesical instillation of ketorolac is safe in humans.

Trospium chloride for the treatment of detrusor instability in children

PURPOSE

We assessed the efficacy and most appropriate dosage of trospium chloride (TCl) for managing bladder instability in children as compared with a placebo.

MATERIALS AND METHODS

A total of 58 patients with bladder instability were allocated at random to 1 of 5 groups-10, 15, 20 or 25 mg TCl, or placebo administered daily in a multicenter, randomized, single-blind clinical study. Patients were treated for 21 days, and current symptoms, voiding diary and urodynamic values were collected at the beginning and end of the treatment period. All adverse events were recorded at the last visit.

RESULTS

Of 50 patients treated with TCl 41 (82%) had a positive therapeutic result (excellent, good or fair) versus only 3 of 8 patients with improvement in the placebo group (37.5%, p = 0.006). In all responding patients clinical symptoms either resolved or decreased markedly, and in 37 (74%) this improvement was accompanied by urodynamic improvement. In these 37 children the average number of uninhibited contractions decreased by 54.3% (p <0.0001) and the volume at first contraction increased by 71.4% (p = 0.001). There were no statistically significant differences with regard to therapeutic efficacy between TCl dosages. Fourteen patients (9 with TCl, 5 with placebo) showed no clinical improvement, although some had improved urodynamic parameters. Furthermore, TCl was well tolerated with few patients (10%) experiencing adverse effects.

CONCLUSIONS

Trospium chloride (10 to 25 mg total daily dosage, split into 2 doses) is an effective option for the management of detrusor instability in children.

The spectrum of urological disease in patients with spina bifida

BACKGROUND

[corrected] Urological complications are the major cause of ill health during childhood and adult life of patients with spina bifida but the significance of urinary tract disease on the individual and the healthcare services is underemphasised.

AIM

To assess the effects of spina bifida on the individual and the healthcare services.

METHODS

A retrospective review was performed to assess the frequency and significance of urological conditions requiring hospital attendance in patients with spina bifida currently attending a specialised multidisciplinary clinic over a period of six months.

RESULTS

Urinary sepsis accounted for the majority of admissions (62%), while 38 of 62 patients required 60 surgical procedures. Targeting the primary urological abnormality (the dysfunctional and usually poorly compliant bladder) allows implementation of effective treatments, including regular intermittent bladder catherisation (52%) in order to preserve upper renal tract function. Associated postural abnormalities complicated both conservative and interventional therapies.

CONCLUSION

This study highlights the surgical commitment for units caring for patients with spina bifida, the important considerations for the future healthcare services, and the range and severity of urological diseases encountered by these patients.

Intravesical oxybutynin: a local anesthetic effect on bladder C afferents

PURPOSE

Intravesical oxybutynin is used to control bladder overactivity in patients who are refractory to or cannot tolerate oxybutynin given orally. Although it is clinically effective, the mode of action of intravesical oxybutynin remains unclear. We tested the influence of intravesical oxybutynin on single fiber pelvic nerve afferents from the rat bladder.

MATERIALS AND METHODS

A total of 15 single afferent bladder units were identified. Based on conduction velocity they were grouped as Adelta or C fibers. The effect of repeat bladder filling was studied on the mechanosensitive properties of these units. Oxybutynin was than instilled and left in the bladder for 15 minutes. Unitary afferent activity was again analyzed 15, 60 and 90 minutes after the drug was removed.

RESULTS

Repeat bladder filling did not change nerve activity in Adelta or C fibers. At 15 minutes after oxybutynin was washed out of the bladder C fiber afferents responded significantly less to intravesical pressure and volume compared with control filling. At 60 minutes C fibers partly regained mechanosensivity. After 90 minutes sensitivity still increased without achieving the response level before oxybutynin. No significant changes were noted in Adelta fibers during repeat bladder filling or after oxybutynin instillation.

CONCLUSIONS

In this study we showed that intravesical oxybutynin has a direct anesthetic effect within the bladder wall. It temporarily desensitizes C fiber afferents, which could explain its clinical benefits in decreasing symptoms of bladder overactivity. No measurable effect was found on Adelta fibers.

Neurological disorders cerebrovascular disease and parkinsonism

To store and expel urine at appropriate intervals, the lower urinary tract requires extensive input and control from the peripheral autonomic, somatic, and central nervous systems. Neurological disorders, such as cerebrovascular disease and Parkinson's disease, often cause functional disturbances of the lower urinary tract.