Dry mouth with conventional and controlled-release oxybutynin in urinary incontinence. The Ditropan XL Study Group

Effects of oxybutynin in children with posterior urethral valves post fulguration: Report in a select cohort of children

Objectives:

Posterior urethral valves (PUV) is the commonest obstructive uropathy with varied consequences. Though valve fulguration is the treatment of choice, appropriate bladder management modifies outcome and includes rational use of anticholinergics. Here, we aim to evaluate the effects of oxybutynin on the bladder and urinary tract morphology and function. Concurrently, we document adverse effects encountered, patient compliance, and medication adherence.

Methods:

A retrospective study of children below 5 years of age (2012–2017) post fulguration and on oxybutynin for at least 6 months. Patient demographics, clinical features, renal ultrasound, micturating cystourethrogram, dimercaptosuccinic acid scan, adverse effects, and pill count for medication adherence were collated.

Results:

48 children below the age of 5 years were included, and 12 were excluded either due to the presence of concomitant problems or were not on oxybutynin. Of the 36, four were lost to follow-up and one had died due to an unrelated condition. Thus, a total of 31 children were analyzed. At follow-up, 28/31 patients were asymptomatic, two had daytime incontinence, and one had recurrent urinary tract infection. All patients except one have preserved renal function tests. On ultrasonography, hydroureteronephrosis worsened in only 1/25 children and two showed significant post void residues. The resolution of vesicoureteral reflux was noted in almost 50%. 4/31 renal units had progressive scars. Only two parents defaulted medication. Urodynamic study done in half of these children showed stable bladder pressures except in two.

Conclusion:

Oxybutynin therapy following adequate valve fulguration aids upper tracts preservation by stabilizing deranged bladder dynamics. The medication is well tolerated with minimal or no side effects.

The clinical pharmacology of the medical treatment for overactive bladder in adults

INTRODUCTION

Overactive bladder is a prevalent symptom complex that affects the patient's quality of life. Any disruption between the neuronal micturition pathway can lead to bladder overactivity. Neurogenic causes, myogenic causes, aging, bladder outlet obstruction, sex, and psychological factors are some of the factors contributing to bladder overactivity. The complaint of any symptoms of OAB, which is highly prevalent and affects overall QOL, often needs therapeutic interventions. When conservative therapy methods fail, the addition of medications is recommended. The most commonly used agents for the treatment of OAB are antimuscarinic drugs. New classes of drugs, such as beta-3 agonists, have enriched our pharmacologic armamentarium.

AREAS COVERED

In this review, with a special focus on oral pharmacological treatments, we discussed the definition, etiology, symptoms, diagnosis, and management of OAB.

EXPERT OPINION

OAB is a multifactorial condition with every patient presenting with a different collection of symptoms and signs. Medical therapies should be given in conjunction with behavioral therapies. Using high or low doses, flexible doses, and stopping or changing the medications are interchangeable strategies based on the level of treatment efficacy and patient satisfaction.

Anticholinergic use in children: Persistence and patterns of therapy

INTRODUCTION

Overactive bladder (OAB) symptoms are complex and generally require long-term therapy. Nevertheless, it has been demonstrated that persistence rates of antimuscarinic drug use are low in adults. Better understanding of the treatment patterns of children treated with antimuscarinics could help to improve drug management. Our objective was to evaluate persistence rates of patients under 20 years of age on antimuscarinic therapy over a four-year period.

METHODS

Patients having received a first-ever antimuscarinic drug prescription between April 2007 and March 2008 were identified using IMS Brogan's Public and Private Drug Plans database. Canadian drug claims data from Private Drug Plans, Régie de l'Assurance Maladie du Québec, and Ontario Public Drug Plans were analyzed retrospectively. Patients were followed for four years to assess the prescribed drugs, the lines of treatment, and the duration of each treatment.

RESULTS

Data were available for 374 patients. The most prescribed drug as a first-line therapy was oxybutynin (87.2%), followed by tolterodine LA (5.9%). Patients refilled their index prescriptions for an average of 429 days. Solifenacin had the highest mean duration of index therapy (765 days). The median number of antimuscarinics prescribed was one. At the end of the followup, 44 patients were still on therapy. Reasons for discontinuation of treatment were not available.

CONCLUSIONS

Overall discontinuation rate of antimuscarinic therapy in children is comparable to what has been reported in adult patients with OAB. However, children seem to persist on the medication for a longer duration before adherence rates start declining. The low rate of persistence highlights the need to identify the reasons for discontinuation of therapy in children in order to obtain better persistence rates.

Overactive bladder - 18 years - Part II

Traditionally, the treatment of overactive bladder syndrome has been based on the use of oral medications with the purpose of reestablishing the detrusor stability. The recent better understanding of the urothelial physiology fostered conceptual changes, and the oral anticholinergics - pillars of the overactive bladder pharmacotherapy - started to be not only recognized for their properties of inhibiting the detrusor contractile activity, but also their action on the bladder afference, and therefore, on the reduction of the symptoms that constitute the syndrome. Beta-adrenergic agonists, which were recently added to the list of drugs for the treatment of overactive bladder, still wait for a definitive positioning - as either a second-line therapy or an adjuvant to oral anticholinergics. Conservative treatment failure, whether due to unsatisfactory results or the presence of adverse side effects, define it as refractory overactive bladder. In this context, the intravesical injection of botulinum toxin type A emerged as an effective option for the existing gap between the primary measures and more complex procedures such as bladder augmentation. Sacral neuromodulation, described three decades ago, had its indication reinforced in this overactive bladder era. Likewise, the electric stimulation of the tibial nerve is now a minimally invasive alternative to treat those with refractory overactive bladder. The results of the systematic literature review on the oral pharmacological treatment and the treatment of refractory overactive bladder gave rise to this second part of the review article Overactive Bladder - 18 years, prepared during the 1st Latin-American Consultation on Overactive Bladder.

Urinary incontinence in men: current and developing therapy options

INTRODUCTION

Urinary incontinence in men is a significant and often underappreciated problem. Men can have urgency and or stress incontinence. Urgency incontinence as part of the overactive bladder (OAB) syndrome and can often coexist with benign prostatic obstruction (BPO) in men and the initial treatment of this is conservative lifestyle changes and then medical therapy.

AREAS COVERED

This literature review aims to cover synthetic drugs currently utilised to treat urinary incontinence in men that are phase III and onwards. Neurological incontinence and surgical treatment options for male urinary incontinence are beyond the scope of this review.

EXPERT OPINION

The most common form of urinary incontinence in men is urgency incontinence secondary to an OAB, which often co-exists in men, with bladder outflow obstruction (BOO). The pharmacotherapy options to treat OAB include antimuscarinics, β3 agonists and phosphodiesterase inhibitors. Antimuscarinics and β3 agonists are effective in treating OAB, and have been found to have no increased urinary retention risk in the group of patients with co-existing BPO. Emerging medications include the alternative β3 agonists - solabegron and ritobegron. The future may include novel combinations of these therapies.

Delivery methods for drugs used in the treatment of overactive bladder

INTRODUCTION

Overactive bladder affects a significant portion of the population and results in prescribing of numerous medications for its treatment. Traditional drug delivery systems used in therapy are associated with multiple commonly reported side effects. Adherence rates with use of these medications are low. It is likely that low adherence rates with the use of these drugs are due in some part to drug side effects. It is therefore important that alternate methods for drug delivery be explored to reduce side effect profiles and improve patient compliance.

AREAS COVERED

This article addresses the various forms of drug delivery for overactive bladder medications, focusing on those currently in use. Newer systems of drug delivery are also discussed. Through thorough review of research data, randomized trials and meta analyses, drug delivery systems were evaluated.

EXPERT OPINION

EXPERT OPINION favors the use of the transdermal patch and recognizes the necessity for further research and development of other delivery methods. The patch delivery method offers the most effective means of treating symptoms and minimizing drug related adverse side effects leading to treatment discontinuation. Development of OAB medications aimed at alternate receptor targets has the potential to facilitate the creation of new treatment methods to compete with the current standard of care used in OAB treatment.

Duration of Antimuscarinic Administration for Treatment of Overactive Bladder Before Which One Can Assess Efficacy: An Analysis of Predictive Factors

Purpose:

To determine the duration of antimuscarinic therapy for overactive bladder syndrome (OAB) appropriate for assessment of the efficacy of treatment, and to evaluate the possible predictive factors for response to therapy.

Methods:

All OAB patients who visited a urology outpatient clinic of a tertiary referral center and who were prescribed 5 mg of solifenacin or 4 mg of tolterodine extended release capsules daily were enrolled in the study. Patients were asked to continue therapy for 6 months. All enrolled patients completed the patient perception of bladder condition, overactive bladder symptom score (OABSS), and the modified Indevus Urgency Severity Scale questionnaires. All patients underwent uroflowmetry.

Results:

A total of 164 patients were enrolled and 125 patients (76%) had at least one follow-up visit. The mean follow-up interval was 1 month (range, 0.5–6 months). Sixty-two patients (49.6%; 95% confidence interval [CI], 40.7–58.5) responded to antimuscarinic treatment. The median time for the onset of response was 3 months (95% CI, 1–6). Multivariate Cox proportional-hazards model revealed that elevated baseline OABSS was an independent predictor of responsiveness to therapy. Receiver operating characteristic (ROC) curve analysis revealed an optimal OABSS cutoff value of ≥7, with an area under the ROC curve of 0.79 (95% CI, 0.70–0.88; sensitivity, 91.9%; specificity, 60.7%).

Conclusions:

The median time for a therapeutic response was 3 months, and OABSS was the only predictor for responsiveness. These findings may serve as a guideline when prescribing antimuscarinic treatment for OAB patients.

Are we shortchanging frail older people when it comes to the pharmacological treatment of urgency urinary incontinence?

Overactive bladder and urgency incontinence are common and distressing conditions in older people, for which the first-line pharmacological treatment is a bladder antimuscarinic agent. Of these, oxybutynin is often recommended in guidelines, but is associated with a higher incidence of adverse drug effects, and in particular has been suggested to have deleterious cognitive effects. Despite this, guidelines often suggest oxybutynin as first-line treatment, and insurance based healthcare systems often require oxybutynin to be used as a first-line therapy and fail before reimbursement for the cost of newer anticholinergics is authorised. We reviewed the literature of bladder antimuscarinics in older adults, using the headings overactive bladder, urinary frequency, urgency, urge, oxybutynin, antimuscarinic, older, older people, and frail. In general, oxybutynin had a similar efficacy to other anticholinergic drugs, but a higher incidence of adverse drug events, in particular significant yet unnoticed cognitive impairment. We conclude that oxybutynin should not be used in frail older people.

Phase II drugs that target cholinergic receptors for the treatment of overactive bladder

INTRODUCTION

Overactive bladder (OAB) is a term used to describe the symptom syndrome of urgency, with or without urgency incontinence, usually associated with frequency and nocturia. Antimuscarinics are the most widely prescribed class of drugs for OAB, although their systemic adverse effects limit their use in clinical practice as compliance. This has led to developments in the field.

AREAS COVERED

In this review, the authors describe Phase II drugs that target cholinergic receptors. First, the authors present the new antimuscarinics (tarafenacin and afacifenacin). This is followed by reports on a combination drug (tolenix) containing a muscarinic antagonist (tolterodine) associated with a muscarinic agonist (pilocarpine). Further, the authors discuss the trials of well-known drugs in either new combination therapy (solifenacin and mirabegron) or with new routes of delivery (oxybutynin vaginal ring). Finally, the authors examine the option of targeting nicotinic acetylcholine receptors (dexmecamylamine).

EXPERT OPINION

Different strategies have been adopted to improve the efficacy and tolerability of therapeutics for OAB. Nicotinic receptors represent a novel therapeutic target; however, it is unlikely that antimuscarinic agents will be replaced as standard first-line therapy in the near future.

Cost Effectiveness of Controlled-Release Oxybutynin Compared with Immediate-Release Oxybutynin and Tolterodine in the Treatment of Overactive Bladder in the UK, France and Austria

OBJECTIVE

To estimate the cost effectiveness of controlled-release (CR) oxybutynin compared with immediate-release (IR) oxybutynin and tolterodine in the treatment of overactive bladder (OAB) in Austria, France and the UK.

DESIGN AND SETTING

This was a modelling study on the management of patients with OAB who were >/=18 years of age, and had urge or mixed incontinence with a primary-urge component. The study was performed from the perspective of payers (i.e. the National Health Service [NHS] in the UK, Social Security in France and the Sick Funds in Austria) and patients.

METHODS

Clinical outcomes attributable to managing OAB were obtained from the published literature, and resource utilisation estimates were derived from a panel of clinicians. Using decision analytical techniques, three decision models were constructed depicting the management of OAB with CR oxybutynin, IR oxybutynin and tolterodine over 6 months in the UK, France and Austria. The models were used to estimate the cost effectiveness of CR oxybutynin relative to the other two anticholinergic drugs in each of the three countries and the expected direct patient costs and indirect societal costs (at 2000/2001 prices).

MAIN OUTCOME MEASURES AND RESULTS

Starting OAB treatment with CR oxybutynin instead of either IR oxybutynin or tolterodine in the UK and Austria was found to be a potentially dominant strategy, since it improves clinical outcome at a lower cost, from the payers' perspective. In France, starting OAB treatment with CR oxybutynin instead of either the IR formulation or tolterodine was found to be a potentially cost-effective strategy from the payer's perspective. The expected 6-monthly direct costs to patients were euro230, euro720-920 and euro970-1000 in the UK, France and Austria, respectively. In the UK and Austria, these costs were broadly consistent between initial treatments. However, in France, tolterodine-treated patients would be expected to incur 28% more expenditure than patients treated with the other two drugs. Transportation emerged as the primary cost driver, accounting for at least 60% of patients' out-of-pocket expenditure, in all three countries. Irrespective of the initial treatment, patients would be expected to miss 1-2 days of work over 6 months as a result of their OAB. This equates to an expected lost productivity cost of euro84, euro250 and euro98 in the UK, France and Austria, respectively.

CONCLUSION

Starting OAB treatment with CR oxybutynin is expected to be a clinically more effective strategy than starting with either IR oxybutynin or tolterodine, and potentially the most cost-effective strategy in all three countries.

Pharmacokinetics and toxicity of antimuscarinic drugs for overactive bladder treatment in females

INTRODUCTION

Antimuscarinics (AMs) are the mainstay of pharmacological treatment of overactive bladder (OAB), a symptom complex defined by the presence of urinary urgency, usually associated with frequency and nocturia, with or without urgency urinary incontinence. The AMs used to treat OAB differ in their pharmacological profiles, which may affect their potential for causing adverse effects (AEs).

AREAS COVERED

The present article aims to review the literature about pharmacokinetics (PK) of the different AMs used in the treatment of OAB. Furthermore, the AEs related to the use of these drugs and their incidence are presented. This systematic review is based on material searched and obtained via Medline, Pubmed and EMBASE up to March 2012 using the search terms "adverse events, pharmacokinetics, tolerability" in combination with "darifenacin, fesoterodine, imidafenacin, oxybutynin, propiverine, solifenacin, tolterodine, and trospium."

EXPERT OPINION

Antimuscarinics are the first-line pharmacological treatment for OAB. Despite the development of new molecules that improve their efficacy/safety profile, there are some drugs that are pharmacokinetically more appropriate to be prescribed in specific populations such as patients with neurological disease or the elderly. Moreover, research should be encouraged in evaluating antimuscarinics in conjunction with other drugs such as estrogens or beta-agonists. The identification of prognostic criteria for pharmacological therapy would be helpful.

An overview on mixed action drugs for the treatment of overactive bladder and detrusor overactivity

OBJECTIVES

To provide an overview on the efficacy, tolerability, safety and health-related quality of life (HRQoL) of drugs with a mixed action used in the treatment of overactive bladder (OAB).

EVIDENCE ACQUISITION

MEDLINE database and abstract books of the major conferences were searched for relevant publications from 1966 to 2011 and using the key words 'overactive bladder', 'detrusor overactivity', 'oxybutynin', 'propiverine', and 'flavoxate'. Two independent reviewers considered publications for inclusion and extracted relevant data, without performing a meta-analysis.

EVIDENCE SYNTHESIS

Old and conflicting data do not support the use of flavoxate, while both propiverine and oxybutynin were found to be more effective than placebo in the treatment of OAB. Propiverine was at least as effective as oxybutynin but with a better tolerability profile even in the pediatric setting. Overall, no serious adverse event for any product was statistically significant compared to placebo. Improvements were seen in HRQoL with treatment by the oxybutynin transdermal delivery system and propiverine extended release.

CONCLUSIONS

While there is no evidence to suggest the use of flavoxate in the treatment of OAB, both oxybutynin and propiverine appear efficacious and safe. Propiverine shows a better tolerability profile than oxybutynin. Both drugs improve HRQoL of patients affected by OAB. Profiles of each drug and dosage differ and should be considered in making treatment choices.

Prescription pattern of oxybutynin ER in patients with overactive bladder in real life practice: a multicentre, open-label, prospective observational study

AIMS OF STUDY

To investigate the prescription pattern and dose distribution of the antimuscarinic agent oxybutynin extended release (ER) in patients with overactive bladder (OAB) in actual clinical practice.

MATERIALS AND METHODS

In this multicentre, prospective, observational, flexible-dosing study, the dosage of oxybutynin ER for each patient was adjusted after discussions of efficacy and tolerability between doctor and patient, over a 12 week treatment period. Efficacy was measured by administering the Primary OAB Symptom Questionnaire (POSQ) before and after treatment. Patients were also administered, the patient perception of treatment benefit (PPTB) questionnaire at the end of the study. Adverse events (AE) were documented at each study visit.

RESULTS

Of the 809 patients enrolled, 590 (73.2%) continued to take study medication for 12 weeks. Most patients were prescribed 5 (24.2%) or 10 (68.8%) mg/day oxybutynin ER at the start of treatment. Most were also prescribed 5 (19.1%) or 10 (67.4%) mg/day at the end of treatment, with a dose escalation rate of 14.9%. All OAB symptoms evaluated by the POSQ were improved; 94.1% of patients reported benefits from treatment and 89.3% were satisfied. Independent predictive factors for discontinuation were female, younger age (age ≤ 65), obesity (BMI ≥ 25), severe symptoms (USS, Gr. 5) and larger numbers of other co-medications.

CONCLUSIONS

Most patients were prescribed 5-10 mg/day oxybutynin ER as both starting and maintenance doses, with a dose escalation rate of only 14.9%. Prescription of > 10 mg/day oxybutynin ER was not frequent in real life practice.

Specific pharmacokinetic aspects of the urinary tract

This chapter reviews the evidence for "specific" pharmacokinetics playing a role in currently marketed drugs intended to treat lower urinary tract (LUT) symptoms. Principles of drug targeting include intrinsic properties of drugs or organs as well as drug formulations to modify drug release or to create confinement of drug presence. Prodrugs and specific formulations to deliver high drug concentrations at the site(s) of action as well as other ways to manipulate drug distribution to achieve enrichment in target tissues are considered. In overactive bladder (OAB), specific formulations for oxybutynin have been introduced to reduce the level of side effects of the active drug. Extended release tablet formulations and a topical gel formulation have been introduced, with efficacy similar to immediate release (IR) tablets, but with a reduction in anticholinergic adverse effects. However, these modifications have not led to outstanding performance parameters compared to other anticholinergic drugs marketed as IR formulations. Urinary excretion is discussed as potential mechanism for targeting LUT symptoms, but no strong indications appear to exist that this mechanism would contribute for currently available drugs. Intravesical administration of drugs is not a preferred option and only considered for drugs like botulinum toxin, where the inconvenient application compensates for a reasonable degree of long-term efficacy in severe refractory OAB. Alpha acid glycoprotein binding is discussed as a potential factor to influence drug tissue distribution, and it is concluded that there is reasonable evidence that for tamsulosin this mechanism is responsible for the difference in free fraction of the drug observed in plasma and prostate, which could contribute to its relative absence of blood pressure effects in patients with LUT symptoms related to benign prostate hyperplasia (LUTS-BPH). The principle of irreversible inhibition of type II 5α-reductase as a tool to develop drugs to reduce prostatic levels of dihydrotestosterone is employed by both dutasteride and finasteride for treatment of LUTS-BPH. Of the mechanisms discussed, the principles employed for the 5α-reductase blockers and tamsulosin in this respect can be considered relatively specific for its urological indication.

Persistence and adherence in the treatment of overactive bladder syndrome with anticholinergic therapy: a systematic review of the literature

Overactive bladder syndrome (OAB) is a chronic condition that has an impact on patients' daily activities and health-related quality of life (HRQL). Anticholinergic therapy is often prescribed following insufficient results with behaviour modification alone; however, rates of treatment discontinuation are consistently high. This study systematically reviewed persistence and adherence data in patients with OAB treated with anticholinergic therapy. A search focused on the intersection of OAB, persistence/adherence, and anticholinergic therapy was conducted in MEDLINE and EMBASE. Articles published after 1998 were reviewed and selected for inclusion based on prespecified criteria. A total of 147 articles and two abstracts were included in the review. Results from 12-week clinical trials showed high rates of discontinuation, ranging from 4% to 31% and 5% to 20% in treatment and placebo groups, respectively. Unsurprisingly, rates of discontinuation found in medical claims studies were substantially higher, with 43% to 83% of patients discontinuing medication within the first 30 days and rates continuing to rise over time. Findings from medical claims studies also suggest that over half of patients never refill their initial prescription and that adherence levels tend to be low, with mean/median medication possession ratio (MPR) values ranging from 0.30 to 0.83. The low levels of persistence and adherence documented in this review reveal cause for concern about the balance between the efficacy and tolerability of anticholinergic agents. Strategies should be identified to increase persistence and adherence. New agents and non-pharmacologic alternatives with good efficacy and minimal side effects should be explored.

Efficacy and safety of low-dose propiverine in patients with lower urinary tract symptoms/benign prostatic hyperplasia with storage symptoms: a prospective, randomized, single-blinded and multicenter clinical trial

Purpose

The aim of this study was to evaluate whether low-dose anticholinergics combined with an α1-receptor antagonist would continue the effect of an alpha-blocker, decrease the side effects of anticholinergics, and improve the symptoms of lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH).

Materials and Methods

Two hundred nine men with LUTS/BPH with storage symptoms (International Prostate Symptom Score [IPSS] ≥12; storage symptoms ≥4) were randomly assigned in a prospective, multicentered, and single-blind fashion to either the control group (alfuzosin 10 mg, once daily) or the combined group (alfuzosin 10 mg, once daily, and propiverine 10 mg, once daily) for 2 months. IPSS, maximal urinary flow rate (Qmax), and postvoid residual volume (PVR) were used to grade symptoms, side effects, and the impact on quality of life (QoL) at the start of the study and after 1 and 2 months.

Results

There were no significant differences in patient background, including age, prostate size, Qmax, and PVR, between the control group and the combined group. In the combined group, the IPSS total score and the IPSS storage symptom score were significantly improved compared with the control group. The IPSS voiding symptom score, QoL, Qmax, and PVR did not differ significantly. There were no serious side effects in either group.

Conclusions

Management with an α1-receptor antagonist combined with a low-dose anticholinergic improved the total score and storage symptom score of the IPSS compared with α1-receptor antagonist only group without causing serious side effects. This initial combination medication can be considered an effective and safe treatment modality for LUTS/BPH patients with storage symptoms.

Controlled delivery systems: from pharmaceuticals to cells and genes

During the last few decades, a fair amount of scientific investigation has focused on developing novel and efficient drug delivery systems. According to different clinical needs, specific biopharmaceutical carriers have been proposed. Micro- and nanoparticulated systems, membranes and films, gels and even microelectronic chips have been successfully applied in order to deliver biopharmaceuticals via different anatomical routes. The ultimate goal is to deliver the potential drugs to target tissues, where regeneration or therapies (chemotherapy, antibiotics, and analgesics) are needed. Thereby, the bioactive molecule should be protected against environmental degradation. Delivery should be achieved in a dose- and time-correct manner. Drug delivery systems (DDS) have been conceived to provide improvements in drug administration such as ability to enhance the stability, absorption and therapeutic concentration of the molecules in combination with a long-term and controlled release of the drug. Moreover, the adverse effects related with some drugs can be reduced, and patient compliance could be improved. Recent advances in biotechnology, pharmaceutical sciences, molecular biology, polymer chemistry and nanotechnology are now opening up exciting possibilities in the field of DDS. However, it is also recognized that there are several key obstacles to overcome in bringing such approaches into routine clinical use. This review describes the present state-of-the-art DDS, with examples of current clinical applications, and the promises and challenges for the future in this innovative field.

Adverse event assessment of antimuscarinics for treating overactive bladder: a network meta-analytic approach

Background

Overactive bladder (OAB) affects the lives of millions of people worldwide and antimuscarinics are the pharmacological treatment of choice. Meta-analyses of all currently used antimuscarinics for treating OAB found similar efficacy, making the choice dependent on their adverse event profiles. However, conventional meta-analyses often fail to quantify and compare adverse events across different drugs, dosages, formulations, and routes of administration. In addition, the assessment of the broad variety of adverse events is dissatisfying. Our aim was to compare adverse events of antimuscarinics using a network meta-analytic approach that overcomes shortcomings of conventional analyses.

Methods

Cochrane Incontinence Group Specialized Trials Register, previous systematic reviews, conference abstracts, book chapters, and reference lists of relevant articles were searched. Eligible studies included randomized controlled trials comparing at least one antimuscarinic for treating OAB with placebo or with another antimuscarinic, and adverse events as outcome measures. Two authors independently extracted data. A network meta-analytic approach was applied allowing for joint assessment of all adverse events of all currently used antimuscarinics while fully maintaining randomization.

Results

69 trials enrolling 26′229 patients were included. Similar overall adverse event profiles were found for darifenacin, fesoterodine, transdermal oxybutynin, propiverine, solifenacin, tolterodine, and trospium chloride but not for oxybutynin orally administered when currently used starting dosages were compared.

Conclusions

The proposed generally applicable transparent network meta-analytic approach summarizes adverse events in an easy to grasp way allowing straightforward benchmarking of antimuscarinics for treating OAB in clinical practice. Most currently used antimuscarinics seem to be equivalent first choice drugs to start the treatment of OAB except for oral oxybutynin dosages of ≥10 mg/d which may have more unfavorable adverse event profiles.

Patient-optimized doses of fesoterodine improve bladder symptoms in an open-label, flexible-dose study

OBJECTIVE

To assess changes in overactive bladder (OAB) symptoms and patient-reported outcomes in a post hoc analysis in which subjects from a 12-week, open-label, flexible-dose fesoterodine study were stratified according to whether they opted for dose escalation.

PATIENTS AND METHODS

Subjects with OAB (eight or more micturitions and three or more urgency episodes per 24 h) who reported dissatisfaction with tolterodine within 2 years of screening received fesoterodine 4 mg once daily for 4 weeks, with an optional dose increase to 8 mg after week 4 based on discussion of efficacy and tolerability between the subject and investigator. Subjects completed 5-day diaries, the Patient Perception of Bladder Condition (PPBC) and Urgency Perception Scale (UPS) at baseline and weeks 4 and 12, and the Overactive Bladder Questionnaire (OAB-q) at baseline and week 12. Subjects rated treatment satisfaction at week 12.

RESULTS

Dose escalation to 8 mg at week 4 was chosen by 255 (50%) of 513 subjects. At baseline, subjects who opted for dose escalation at week 4 (escalators) had significantly higher means for all diary variables except urgency urinary incontinence (UUI) episodes, significantly greater OAB-q Symptom Bother scores and significantly lower OAB-q health-related quality of life (HRQL) scores (all P < 0.05) compared to subjects who did not opt for dose escalation (non-escalators). There was no significant difference in the percentage of escalators (51%) and non-escalators (48%) who reported at least one UUI episode on baseline diary. At week 4 (before the decision to escalate was made), all outcomes were significantly improved vs baseline among both groups (all P < 0.0001), although non-escalators had significantly greater improvements in all diary variables and in PPBC and UPS scores than escalators (all P < 0.05), and the 5-day diary-dry rate (i.e. the percentage of subjects with at least one UUI episode on baseline diary and no UUI episodes on week 4 diary) was significantly higher (P = 0.0016) among non-escalators (62%) than among escalators (42%). At week 12, all outcomes were again significantly improved vs baseline among both groups (all P < 0.0001). There were no significant differences between non-escalators and escalators in week 12 improvements for most diary variables, UPS scores, OAB-q Symptom Bother scores, the diary-dry rate (68% vs 60%) or the percentage of subjects who reported treatment satisfaction (82% vs 78%). However, escalators still had significantly greater improvements from baseline in urgency episodes, PPBC scores and OAB-q total HRQL and Coping domains (P < 0.05). Adverse event rates were similar between non-escalators and escalators. Dry mouth was the most frequently reported adverse event; most cases were mild.

CONCLUSION

Flexible-dose fesoterodine significantly improved OAB symptoms and patient-reported outcomes in subjects who chose to remain on the initial 4-mg dose, as well as in the 50% of subjects who escalated to the 8-mg dose after 4 weeks. Non-escalators had significantly fewer OAB symptoms at baseline and significantly greater improvements than escalators before dose escalation. Escalators showed increased symptom relief after dose escalation; improvements in most outcomes were similar among non-escalators and escalators by week 12. Flexible-dose fesoterodine was well tolerated, with similar adverse-event profiles observed in the escalator and non-escalator groups. These results may help clinicians to identify patients more likely to require fesoterodine 8 mg to achieve maximum relief of OAB symptoms and thus facilitate dose escalation in these patients.

Dose escalation improves therapeutic outcome: post hoc analysis of data from a 12-week, multicentre, double-blind, parallel-group trial of trospium chloride in patients with urinary urge incontinence

Background

Flexible dosing of anticholinergics used for overactive bladder (OAB) treatment is a useful strategy in clinical practice for achieving a maximum effective and maximum tolerated level of therapeutic benefit. In this post hoc analysis we evaluated the efficacy and tolerability of trospium chloride treatment for urinary urge incontinence (UUI) with focus on flexible dosing.

Methods

The data came from a 12-week, randomised, double-blind, phase IIIb study in which 1658 patients with urinary frequency plus urge incontinence received trospium chloride 15 mg TID (n = 828) or 2.5 mg oxybutynin hydrochloride TID (n = 830). After four weeks, daily doses were doubled and not readjusted in 29.2% (242/828) of patients in the trospium group, and in 23.3% (193/830) in the oxybuytnin group, until the end of treatment. We assessed the absolute reduction in weekly UUI episodes and the change in intensity of dry mouth, recorded in patients' micturition diaries. Adverse events were also evaluated. Statistics were descriptive.

Results

Dose escalation of either trospium or oxybutynin increased reduction in UUI episodes in the population studied. At study end, there were no relevant differences between the "dose adjustment" subgroups and the respective "no dose adjustment" subgroups (trospium: P = 0.249; oxybutynin: P = 0.349). After dose escalation, worsening of dry mouth was higher in both dose adjusted subgroups compared to the respective "no dose adjustment" subgroups (P < 0.001). Worsening of dry mouth was lower in the trospium groups than in the oxybutynin groups (P < 0.001). Adverse events were increased in the dose adjusted subgroups.

Conclusions

Flexible dosing of trospium was proven to be as effective, but better tolerated as the officially approved adjusted dose of oxybutynin.

Trial registration (parent study)

The study was registered with the German Federal Institute for Drugs and Medical Devices (BfArM, Berlin, Germany), registration number 4022383, as required at the time point of planning this study.

Tolerability of 5 mg solifenacin once daily versus 5 mg oxybutynin immediate release 3 times daily: results of the VECTOR trial

PURPOSE

Although antimuscarinic treatment is indicated for overactive bladder, many patients discontinue it because of dry mouth. Of available antimuscarinics oxybutynin is associated with the highest dry mouth rate. We compared the safety and tolerability of 5 mg solifenacin vs 15 mg oxybutynin immediate release.

MATERIALS AND METHODS

At 12 Canadian centers a total of 132 patients with overactive bladder symptoms (greater than 1 urgency episode per 24 hours, and 8 or greater micturitions per 24 hours) were randomized to 5 mg solifenacin once daily or 5 mg oxybutynin 3 times daily for 8 weeks. The primary end point was the incidence and severity of dry mouth reported after direct questioning. Efficacy end points (3-day diary documented changes in urgency, frequency, incontinence, nocturia and voided volume), and changes on the Patient Perception of Bladder Condition scale and the Overactive Bladder Questionnaire were evaluated secondarily.

RESULTS

Of patients on solifenacin vs oxybutynin immediate release 35% vs 83% reported dry mouth (p <0.0001). Of patients reporting dry mouth severity was graded moderate by 13% and 42% of those on solifenacin and oxybutynin immediate release, and severe by 13% and 28%, respectively (p = 0.001). Patients in each group showed improvements in efficacy end points, and Patient Perception of Bladder Condition scale and Overactive Bladder Questionnaire scores from baseline to treatment end.

CONCLUSIONS

Significantly fewer patients on 5 mg solifenacin once daily reported dry mouth vs those receiving 5 mg oxybutynin immediate release 3 times daily. Significantly fewer patients on solifenacin reported moderate/severe dry mouth. Significantly fewer patients on solifenacin withdrew from study due to dry mouth and there were significantly fewer overall adverse events. Solifenacin and oxybutynin immediate release were efficacious in decreasing efficacy end points, and improved Patient Perception of Bladder Condition scale and Overactive Bladder Questionnaire results from baseline to treatment end.

Canadian cost-effectiveness analysis of solifenacin compared to oxybutynin immediate-release in patients with overactive bladder

OBJECTIVE

To estimate the cost effectiveness of solifenacin 5 mg/day compared to oxybutynin immediate-release (IR) 15 mg/day in patients with overactive bladder, from the perspective of the Canadian healthcare (payer) system.

RESEARCH DESIGN AND METHODS

A Markov model was adapted to estimate the incremental cost per quality-adjusted life-year (QALY) of solifenacin and oxybutynin IR over a 1-year time horizon, based on efficacy and discontinuation data from the Canadian VECTOR (VEsicare in Comparison To Oxybutynin for oveRactive bladder patients) study. In the model, patients who discontinued treatment were offered tolterodine extended release 4 mg/day as second-line. Model robustness was tested using various sensitivity analyses. Utility values were derived from published literature; incontinence pads were included in a secondary analysis.

RESULTS

In the base-case analysis, total costs over 1 year were CAN$695 and CAN$550 in the solifenacin and oxybutynin IR groups, respectively. When including incontinence pad costs, there was an incremental saving of CAN$1,831 per patient with solifenacin. Solifenacin was associated with an incremental QALY gain of 0.01 over 1 year. In the base-case analysis without incontinence pads, the incremental cost-utility ratio for solifenacin was CAN$14,092. Probabilistic analyses showed no overlap in the 95% confidence intervals for total costs or QALYs with or without incontinence pads. Solifenacin was cost effective in >90% of cases, based on a willingness-to-pay threshold of CAN$50,000 per additional QALY, irrespective of whether pad costs were included in the model. The most influential variables were the discontinuation rates and the cost of incontinence pads. Limitations of the analysis relate mainly to the fact that data in the VECTOR study were collected using a direct questioning approach, which might have increased the reporting of dry mouth.

CONCLUSIONS

Solifenacin 5 mg/day was a cost-effective treatment compared with oxybutynin IR 15 mg/day.

TRIAL REGISTRATION

NCT00431041 (of the VECTOR study, upon which the analysis in this paper was based).

The pharmacokinetic profile of fesoterodine 8 mg with daytime or nighttime dosing

PURPOSE

Diurnal variation can affect drug pharmacokinetics. Fesoterodine is a new antimuscarinic drug for the treatment of overactive bladder (OAB). We estimated the relative bioavailability of 5-hydroxymethyl tolterodine (5-HMT), the active metabolite of fesoterodine, following nighttime and daytime administration.

METHODS

In this randomized, open-label, two-period, two-treatment crossover, single-dose study, healthy subjects received daytime and nighttime oral dosing of fesoterodine 8-mg sustained-release tablets, separated by a minimum 60-h washout period. Blood samples for 5-HMT PK determination were collected before dosing and at specified intervals up to 48 h postdose. Safety was assessed by adverse event (AE) reports.

RESULTS

Fourteen subjects completed the study. Plasma concentration versus time profiles (AUC) of 5-HMT were similar for daytime and nighttime dosing. Mean AUC(infinity) 5-HMT values were 47.9 and 51.4 ng h/mL for nighttime and daytime dosing, respectively; the mean time to reach maximum concentration (C(max)) values were 3.9 and 5.0 ng/mL, respectively. Nighttime versus daytime AUC(infinity) and C(max) ratios of 5-HMT were 93 and 79%, respectively; 90% confidence intervals (CIs) indicated equivalence for AUC(infinity) but not for C(max). The median time to reach maximum concentration (T(max)) was 5.0 h for both dosing regimens, and the mean terminal elimination half-life (T((1/2))) was 5.9 and 5.7 h for nighttime and daytime dosing, respectively. Seven treatment-related AEs, most commonly headache, occurred in five subjects.

CONCLUSIONS

The AUC values for daytime and nighttime administration of fesoterodine were equivalent. The 21% reduction in the C(max) for nighttime dosing is unlikely to be clinically relevant. No safety issues were apparent. These results support both daytime and nighttime administration of fesoterodine for OAB treatment.

Oxybutynin extended release for the management of overactive bladder: a clinical review

Overactive bladder (OAB) is a common condition which negatively impacts the quality of life of afflicted patients. This can result in alterations in social interactions at home, in the workplace and in the community, often leading to depression and poor self esteem as well as loss of productivity. Traditional mainstays of treatment include both behavioral therapy and pharmacotherapy. Oxybutynin immediate release (IR) represents the first such medication approved by the FDA specifically for treatment of OAB in 1975. Nevertheless, bothersome side effects in addition to thrice daily dosing often led to treatment cessation which raised the question that patients may actually prefer to live with their OAB symptoms rather than incur side effects or complex dosing schemes. Pharmacological advances ultimately led to development of a long-acting formulation of oxybutynin in the form of oxybutynin extended release (ER) with the hope that this drug would maintain efficacy while decreasing bothersome side effects and improve compliance with the convenience of once daily dosing regimen. This paper will review the major clinical studies involving oxybutynin ER as well as its role in different patient populations and potential concerns with its use.

The effects of reformulation: improved therapeutic index

Antimuscarinic agents are the treatment of choice for overactive bladder syndrome. Due to the development of novel delivery systems, extended-release formulations of oxybutynin, tolterodine, and trospium chloride are now available. In addition to the convenience of once-daily dosing, the new formulations of these commonly prescribed agents have improved their therapeutic index, striking a better balance between efficacy and tolerability.

Efficacy and safety of solifenacin succinate in Korean patients with overactive bladder: a randomised, prospective, double-blind, multicentre study

PURPOSE

We assessed the efficacy and safety of solifenacin compared with tolterodine for treatment of overactive bladder (OAB) in Korean patients.

MATERIALS AND METHODS

The study was randomised, double-blind, tolterodine-controlled trial in Korea. Patients had average frequency of >or= 8 voids per 24 h and episodes of urgency or urgency incontinence >or= 3 during 3-day voiding diary period. Patients were randomised to 12-week double-blind treatment with either tolterodine immediate release (IR) 2 mg twice daily (TOL4) or solifenacin 5 mg (SOL5) or 10 mg (SOL10) once daily. The outcome measure was mean change in daily micturition frequency, volume, daily frequency of urgency incontinence, urgency and nocturia from baseline to week 12. Quality of life was assessed using the King's Health Questionnaire.

RESULTS

A total of 357 were randomised and 329 were evaluated for efficacy. All voiding parameters recorded in micturition diary improved after treatment in all three groups. Mean changes in volume voided were 19.30 ml (26.69%) in TOL4, 30.37 ml (25.89%) in SOL5 and 37.12 ml (33.36%) in SOL10 group (p = 0.03). Speed of onset of SOL10 efficacy on urgency incontinence was faster than that of SOL5 and TOL4. Quality of life improved in all three groups. Dry mouth was the most common adverse event; its incidence was the lowest in SOL5 group (7.63%, compared with 19.49% and 18.64% in SOL10 and TOL4 groups respectively).

CONCLUSIONS

Solifenacin succinate 5 and 10 mg once daily improve OAB symptoms with acceptable tolerability levels compared with tolterodine IR 4 mg. Solifenacin 5 mg is a recommended starting dose in Korean patients with OAB.

Drug–drug interactions in the metabolism of imidafenacin: Role of the human cytochrome P450 enzymes and UDP-glucuronic acid transferases, and potential of imidafenacin to inhibit human cytochrome P450 enzymes

Imidafenacin (IM), 4-(2-methyl-1H-imidazol-1-yl)-2,2-diphenylbutanamide, is a newly synthesized antimuscarinic drug developed for the treatment of overactive bladder. To predict clinically relevant drug interactions in the metabolism of IM, the paper investigated: (1) the major enzymes responsible for the metabolism of IM, (2) the effects of concomitant drugs on the inhibition of metabolism of IM, and (3) the effects of IM and its metabolites on the inhibition of human cytochrome P450 (CYP). The elimination of IM and production of oxidative metabolites were mainly catalysed by recombinant CYP3A4, and the elimination of IM by human liver microsomes (HLM) was markedly inhibited by co-incubation with ketoconazole. The production of the N-glucuronide metabolite was only catalysed by recombinant UGT1A4. Clinically established CYP3A4 inhibitors including itraconazole, ketoconazole, erythromycin and clarithromycin inhibited the elimination of IM in HLM. IM and its major metabolites did not affect the activities of CYP enzymes in vitro. The results suggest that the major enzymes responsible for the metabolism of IM are CYP3A4 and UGT1A4, and oxidative metabolism of IM is reduced by concomitant administration of CYP3A4 inhibitors. In contrast, IM and its metabolites have no inhibitory effect on the CYP-mediated metabolism of concomitant drugs.

How to choose the initial drug treatment for overactive bladder

Antimuscarinics are the treatment of choice for patients suffering from overactive bladder syndrome (OAB). Clinical experience and the literature support the efficacy, tolerability, and safety of each agent. With increasing data and educational and marketing efforts, many health care providers are uncertain which antimuscarinic should be prescribed first. It is important to recognize that there is not one superior agent, and that the individual response to each antimuscarinic is highly variable. This paper uses peer-reviewed literature to elucidate various agents with respect to efficacy, tolerability, and safety, to help readers understand the pros and cons associated with each drug so they may better manage patients with OAB.

Formulation study of oxybutynin patches

The present feasibility study was designed to obtain a monolayer patch containing oxybutynin (OXY) avoiding chemical permeation enhancers. The highest flux was obtained with a polydimethylsiloxane matrix patch. Because OXY crystals were detected in the matrix within a week, two amino methylmethacrylate copolymers (Eudragit E or Eudragit RS) were used as OXY crystallization inhibitors. A preliminary in vivo study indicated that flux from the stabilized patches had to be increased about 30-40%. This goal was reached by occlusion with a polyethylene layer.

Maximizing anticholinergic therapy for overactive bladder: has the ceiling been reached?

Urinary incontinence affects an estimated 20-33% of adults the USA and 55% of the country's elderly [1], having a more substantial impact on the physical and mental dimension of quality of life than other common chronic diseases. Muscarinic receptor antagonists, including oxybutynin, tolterodine, trospium chloride, darifenacin, and solifenacin, are front-line therapies for overactive bladder (OAB), with an efficacy of 65-75% in reducing major symptoms. Strategies to increase the therapeutic index have included behavioural therapy, flexible dosing, and dose escalation, as well as newer formulations that reduce anticholinergic side-effects. Among approved OAB agents, the oxybutynin transdermal-delivery system has been associated with a lower incidence of dry mouth than immediate- and extended-release formulations of traditional agents. With a low propensity for drug interactions and dry mouth, it is a likely candidate for older patients taking multiple medications. The transdermal patch bypasses systemic and first-pass metabolism, avoiding higher plasma concentrations of the active metabolite (N-desethyloxybutynin) thought to be associated with dry mouth symptoms. Anticholinergics have a significant role to play in the management of OAB; newer drugs targeted toward muscarinic receptors, and novel delivery systems, continue to increase the therapeutic index for this condition.

Safety and tolerability of extended-release oxybutynin once daily in urinary incontinence: combined results from two phase 4 controlled clinical trials

Early studies of extended-release oxybutynin in patients with overactive bladder used adjusted-dose regimens ranging from 5 to 30 mg/day to achieve an optimal balance of efficacy and tolerability. The safety and tolerability of extended-release oxybutynin at a fixed dose of 10 mg once daily (commonly prescribed in clinical practice) is reported using pooled data from 2 multicenter, randomized, double-blind, parallel-group trials with a similar study design. One study compared extended-release oxybutynin with immediate-release tolterodine 2 mg bid. The other study compared extended-release oxybutynin with extended-release tolterodine 4 mg qd. In total, 576 patients received extended-release oxybutynin, 399 received extended-release tolterodine, and 193 received immediate-release tolterodine. The incidence of adverse events (AEs) was similar in the three treatment groups (extended-release oxybutynin, 70%; extended-release tolterodine, 64%; and immediate-release tolterodine, 79%). The most common adverse event was dry mouth (extended-release oxybutynin, 29%; extended-release tolterodine, 22%; and immediate-release tolterodine, 33%). Other AEs occurring in more than 5% of patients in any treatment group included constipation, diarrhea, headache, urinary tract infection, pain, dyspepsia, and peripheral edema, with no apparent difference across treatment groups. Most AEs (>90%) were mild or moderate in intensity in all treatment groups. The proportion of patients who discontinued study medication due to AEs was 6.1, 4.8, and 7.8% in the extended-release oxybutynin, extended-release tolterodine, and immediate-release tolterodine groups, respectively. In total, 1.2, 1.0, and 1.6% of patients in the extended-release oxybutynin, extended-release tolterodine, and immediate-release tolterodine groups, respectively, discontinued study medication due to dry mouth.

Pharmacoeconomic evaluation of antimuscarinic agents for the treatment of overactive bladder

STUDY OBJECTIVE

To compare the cost-effectiveness of various antimuscarinic agents for the treatment of overactive bladder (OAB).

METHODS

A decision-analysis model was developed and included clinical outcomes (i.e., therapy continued or discontinued, treatment success or failure, OAB-induced comorbidities) and costs for drugs and treatment of OAB-induced comorbidities (i.e., urinary tract infections, fractures, depression, and skin infections). Treatment success was defined as complete continence. A systematic MEDLINE literature search from January 1990-January 2006 identified English-language articles concerning the eight antimuscarinic drugs: darifenacin, solifenacin, trospium, immediate-release oxybutynin, extended-release oxybutynin, transdermal oxybutynin, immediate-release tolterodine, and extended-release tolterodine. Probabilities and cost data for these drugs were retrieved from the literature, and drug costs were based on 2005 average wholesale prices. The analysis was constructed from a payer's perspective. The time frame for the model was 3 months.

RESULTS

Expected costs for each patient with OAB ranged from $3373 when treated with solifenacin to $3769 when treated with immediate-release oxybutynin. The average cost/patient with continued and successful treatment was lowest for solifenacin ($6863). Solifenacin dominated all other antimuscarinic agents because they were associated with high costs and low effectiveness. Success rates were the key parameters driving the sensitivity analysis.

CONCLUSION

Among various antimuscarinic agents, solifenacin 5 mg had the lowest costs and highest effectiveness in the treatment of OAB.

Improved efficacy of extended release oxybutynin in children with persistent daytime urinary incontinence converted from regular oxybutynin

OBJECTIVES

To examine the response to conversion from regular oxybutynin (Ditropan) to an extended-release form (Ditropan XL) in children with persistent daytime urinary incontinence.

METHODS

A retrospective review of patients with daytime wetting who switched from Ditropan to Ditropan XL included patient age, sex, reason for the change in medication, uroflowmetry findings before and after the change, side effects, and duration and dosage of the medication. The data were analyzed using a paired, two-tailed t test, with P <0.05 considered significant.

RESULTS

Twenty-seven patients were followed up for an average of 35.8 months. A lack of improvement (n = 11), convenience (n = 6), side effects (n = 2), and a dislike of the taste (n = 2) were identified as reasons for changing to the extended release form. The mean dosage of Ditropan and Ditropan XL did not differ significantly (0.40 and 0.38 mg/kg/day, respectively). After the change to Ditropan XL, 6 patients had a resolution of side effects and 7 developed new side effects. Of the 27 patients, 13 became dry or had significant improvement by the first visit after the change to Ditropan XL. Significant increases in voided volume (38% versus 53%; P <0.01) and total bladder capacity (55% versus 70%; P = 0.03), normalized for age-expected bladder capacity, occurred by the first clinic visit after beginning Ditropan XL. No significant changes in the postvoid residual urine volume occurred.

CONCLUSIONS

The frequency of wetting decreased and the voided volume and bladder capacity increased after a change to Ditropan XL in children with persistent wetting when taking Ditropan.

Clinical spectrum of the osmotic-controlled release oral delivery system (OROS), an advanced oral delivery form

BACKGROUND

The osmotic-controlled release oral delivery system, OROS, is an advanced drug delivery technology that uses osmotic pressure as the driving force to deliver pharmacotherapy, usually once-daily, in several therapeutic areas.

OBJECTIVE

The purpose of this review is to discuss the evolution of OROS technology and examine the many therapeutic areas where OROS products are being used.

METHODS

A search of Medline and EMBASE were performed using the keywords 'OROS' and 'osmotic delivery' for the period January 1990 to June 2005. Data were also obtained from the manufacturers' websites and associated publications.

RESULTS

OROS technology has evolved over the last 30 years, resulting in four systems: the elementary osmotic pump; the two-layer osmotic push-pull tablet; the advanced longitudinally compressed tablet multilayer formulation; and, the L-OROS system. OROS technology is employed for drug delivery in many therapeutic areas including: cardiovascular medicine, endocrinology, urology, and central nervous system (CNS) therapeutics. Two calcium channel blockers utilizing OROS technology for the treatment of hypertension are nifedipine and verapamil. Glipizide extended-release is used for the treatment of type 2 diabetes. Doxazosin is used for the treatment of benign prostatic hyperplasia, and oxybutynin for overactive bladder. Most recent developments are with drugs that affect the CNS, including the use of methylphenidate for treatment of attention deficit hyperactivity disorder, paliperidone extended-release and OROS hydromorphone, which are under clinical development for schizophrenia and chronic pain, respectively.

CONCLUSIONS

Drug delivery using the various OROS products can result in an improved safety profile, stable drug concentrations, uniform drug effects, and reduced dosing frequency. OROS technology has also enabled the use of an effective starting dose, without the need for dose titration, which allows the achievement of symptom control much earlier than that observed with immediate-release preparations. Such attributes can enhance patient compliance and convenience, thereby ensuring efficacy and improving patient outcomes.

Surgical Innovations in Pelvic Organ Prolapse and Incontinence

Pelvic organ prolapse (POP) and urinary incontinence (UI) are common problems facing the geriatric woman. Many patients may find great benefit from medical or conservative treatments; however, surgical options are commonly used in many cases. This article examines the current medical and surgical innovations for POP and UI that have the potential to improve the patient's quality of life.

Comparison of dry mouth in women treated with extended-release formulations of oxybutynin or tolterodine for overactive bladder

The incidence, severity and tolerability of dry mouth was compared in 790 women with overactive bladder who were treated with extended-release oxybutynin chloride 10 mg/day or extended-release tolterodine tartrate 4 mg/day for 12 weeks in a multicenter, double-blind, parallel-group study. Dry mouth was the most common adverse event associated with treatment, with an incidence rate of 28.1% in the oxybutynin group and 21.6% in the tolterodine group (P = 0.039). The majority of dry mouth events were mild in both treatment groups. Severe dry mouth occurred in 1.5% and 0.5% of patients in the oxybutynin and tolterodine groups, respectively (P = 0.173). Seven patients on extended-release oxybutynin and 4 patients on extended-release tolterodine discontinued treatment due to dry mouth (P = 0.380). The results of this analysis showed that dry mouth was common with both treatments, but most events were mild; there was no difference in the rate of severe dry mouth or in the rate of withdrawal due to dry mouth.

The overactive bladder: review of current pharmacotherapy in adults. Part 1: pathophysiology and anticholinergic therapy

Overactive bladder is a syndrome characterised by urinary urgency, with or without urge incontinence, and usually with frequency and nocturia. It affects millions of people of all ages worldwide and causes significant morbidity, especially in terms of health-related quality of life. It poses a huge economic burden on health resources. Managing such patients involves a thorough history, physical examination and the use of pertinent investigations before the initiation of treatment. Therapy consists of lifestyle changes, bladder training, anticholinergics, second-line agents such as resiniferatoxin instillation or botulinum toxin injections into the bladder in refractory cases and, finally, in intractable cases, surgery. In the first part of this review of pharmacotherapy for the treatment of this condition, the focus is on the pathophysiological factors potentially involved in overactive bladder and covers the wide range of currently available first-line anticholinergic agents. Treatment algorithms are suggested on the basis of current literature.

A double-blind randomized dose-response study comparing daily doses of 5, 10 and 15 mg controlled-release oxybutynin: balancing efficacy with severity of dry mouth

OBJECTIVE

To assess the efficacy, incidence of dry mouth and overall satisfaction with initial doses of 5, 10 and 15 mg of a new, once-daily, controlled-release (CR) form of oxybutynin for treating urge urinary incontinence (UUI).

PATIENTS AND METHODS

Patients who reported urinary incontinence (UI) (one or more episodes/diary) and voiding frequency (eight or more voids/day) or urgency (one or more episodes/diary) during a 2-week baseline were randomized to once-daily 5, 10 or 15 mg CR oxybutynin for 4 weeks. Daily episodes of UI, voids, urgency, adverse events, dry mouth and satisfaction were recorded in a 3-day diary at baseline and after 4 weeks of treatment. In all, 237 patients were randomized and evaluated.

RESULTS

Episodes of UI, voids and urgency were significantly reduced over the study period at all doses. Daily UI episodes were significantly lower with 15 mg/day than 5 and 10 mg/day. Dry mouth symptoms were similar in the 10 and 15 mg/day groups, and higher than in the 5 mg/day group. However, significantly greater overall satisfaction was reported with 15 than 5 mg/day.

CONCLUSIONS

There were significant dose-response relationships with CR oxybutynin for both UI episodes and dry mouth. The greatest satisfaction was with 15 mg/day, and the severity of dry mouth was comparable at 10 mg/day, indicating that greater efficacy at the higher dose did not compromise tolerability.

The emergence of new drugs for overactive bladder

Overactive bladder is a common and distressing problem. Standard therapy is directed towards modifying the detrusor motor sensitivity and response via anticholinergic medication. Currently available medications are reviewed and alternative targets for treatment are presented.

Efficacy and safety of extended release oxybutynin for the treatment of urge incontinence: an analysis of data from 3 flexible dosing studies

PURPOSE

We assessed the efficacy and safety of extended release (ER) oxybutynin at individualized doses for urge urinary incontinence.

MATERIALS AND METHODS

Data were combined from 3 flexible dosing studies of a total of 420 patients with urge urinary incontinence or mixed incontinence in whom ER oxybutynin dose adjustments were made to achieve the optimal balance between efficacy and tolerability, as judged by each participant. Individual doses were adjusted in 5 mg increments across a dose range of 5 to 30 mg daily. Efficacy was assessed during maintenance therapy using a 7-day diary.

RESULTS

Data on 368 patients who completed dose adjustment were included in the analysis. In 47% of patients the preferred dose was greater than 10 mg daily. Individualized doses of ER oxybutynin produced a 79.3% decrease from baseline in the total of all incontinence episodes and an 83.2% decrease in urge episodes. Of patients 81% achieved a decrease of at least 70% in all incontinence episodes and 43% achieved total dryness. Moderate or severe dry mouth was reported by 23% of patients and it was cited as the cause for early withdrawal by 1.4% who completed dose adjustment. Therapy was well tolerated. In the pooled sample overall 6.7% of patients cited adverse events as the reason for discontinuing.

CONCLUSIONS

Individualized dosing with ER oxybutynin was associated with highly effective and well tolerated control of urinary incontinence with more than 40% of patients achieving total dryness.

Which anticholinergic drug for overactive bladder symptoms in adults

BACKGROUND

Around 16% to 45% of adults have overactive bladder symptoms (urgency with frequency and/or urge incontinence - 'overactive bladder syndrome'). Anticholinergic drugs are common treatments.

OBJECTIVES

To compare the effects of different anticholinergic drugs for overactive bladder symptoms.

SEARCH STRATEGY

We searched the Cochrane Incontinence Group specialised trials register (searched 17 January 2002) and reference lists of relevant articles. A search for full publications of abstracts identified in January 2002 was completed in July 2003.

SELECTION CRITERIA

Randomised trials in adults with overactive bladder symptoms or detrusor overactivity that compared one anticholinergic drug with another, or two doses of the same drug.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed eligibility, trial quality and extracted data. Data were processed as described in the Cochrane Reviewers' Handbook.

MAIN RESULTS

Forty nine trials, 39 parallel and 10 cross-over designs were included (11,332 adults). Most trials were described as double-blind, but were variable in other aspects of quality. Crossover studies did not present data in a way that could be included in the meta-analysis.Four trials collected quality of life data (the primary outcome measure) using validated measures; none reported useable data. Oxybutynin versus tolterodine: There were no statistically significant differences for patient perceive improvement, leakage episodes or voids in 24 hours, but fewer withdrawals due to adverse events (RR 0.57, 95% CI 0.43 to 0.75), and less risk of dry mouth (RR 0.60, 95% CI 0.54 to 0.66), with tolterodine. Different doses tolterodine: The usual recommended starting dose (2 mg twice daily) was compared with two lower (0.5 mg and 1 mg twice daily), and one higher dose (4 mg twice daily). The effect of 1 mg, 2 mg and 4 mg doses was similar for leakage episodes and micturitions in 24 hours, with greater risk of dry mouth with 2 and 4 mg doses.Extended versus immediate release preparations of oxybutynin and/or tolterodine: There were no statistically significant differences for cure/improvement, leakage episodes or micturitions in 24 hours, or withdrawals due to adverse events, but there were few data. Overall, extended release preparations had less risk of dry mouth. One extended release preparation versus another: There was less risk of dry mouth with oral extended release tolterodine than oxybutynin (RR 0.75, 95% CI 0.59 to 0.95), but no difference between transdermal oxybutynin and oral extended release tolterodine although some people withdrew due to skin reaction at the trandermal patch site.

AUTHORS' CONCLUSIONS

Where the prescribing choice is between oral immediate release oxybutynin or tolterodine, tolterodine might be preferred for reduced risk of dry mouth. With tolterodine, 2 mg twice daily is the usual starting dose, but a 1 mg twice daily dose might be equally effective with less risk of dry mouth. If extended release preparations of oxybutynin or tolterodine are available, these might be preferred to immediate release preparations because there is less risk of dry mouth. There is little or no evidence available about quality of life, costs, or long-term outcome in these studies. There were insufficient data from trials of other anticholinergic drugs to draw any conclusions.

The Effects of Antimuscarinic Treatments in Overactive Bladder: A Systematic Review and Meta-Analysis

OBJECTIVES

To evaluate the tolerability, safety and efficacy of antimuscarinic drugs used to treat overactive bladder and to identify any differences between individual antimuscarinics.

METHODS

Medline, Embase, CCTR and Cinahl databases were searched for published RCTs including an antimuscarinic agent from 1966 to August 2004. Data from included trials were extracted and meta-analysed where possible.

RESULTS

Fifty-six trials were included. The antimuscarinics were found to be safe and efficacious. All antimuscarinics apart from oxybutynin IR were found to be well tolerated. Dry mouth was the most commonly reported adverse event and no drug was associated with an increase in any serious adverse event. There were significant differences between the antimuscarinics in rates of withdrawal and rates and range of adverse events and efficacy outcomes.

CONCLUSIONS

The antimuscarinics have different tolerability and safety profiles, which are clinically significant.

Extended-release formulations of oxybutynin and tolterodine exhibit similar central nervous system tolerability profiles: a subanalysis of data from the OPERA trial

OBJECTIVE

This study was undertaken to compare the central nervous system (CNS) tolerability profiles of the extended-release formulations of oxybutynin chloride and tolterodine tartrate in the treatment of women with overactive bladder (OAB), as observed in the OPERA (Overactive bladder: Performance of Extended Release Agents) trial.

STUDY DESIGN

The OPERA trial was a randomized, double-blind, active-control comparison of the efficacy and safety of extended-release oxybutynin (10 mg/d) and extended-release tolterodine (4 mg/d) given to 790 women with OAB for 12 weeks. The incidence of reported CNS events was compared between the treatment groups by using the Fisher exact test.

RESULTS

The incidence of CNS adverse events was 9% and 8% for the oxybutynin and tolterodine treatment groups, respectively. The difference between groups was not statistically significant. All reported CNS adverse events were rated as mild or moderate in severity. There were no serious treatment-related adverse events in either group, and discontinuation because of a CNS adverse event was infrequent.

CONCLUSION

The extended-release formulations of oxybutynin and tolterodine were observed to be associated with a similar low incidence of CNS adverse events, which were mostly mild or moderate in severity.