Oxybutynin Extended-Release

Ageing and Polypharmacy in Mesenchymal Stromal Cells: Metabolic Impact Assessed by Hyperspectral Imaging of Autofluorescence

The impact of age on mesenchymal stromal cell (MSC) characteristics has been well researched. However, increased age is concomitant with increased prevalence of polypharmacy. This adjustable factor may have further implications for the functionality of MSCs and the effectiveness of autologous MSC procedures. We applied hyperspectral microscopy of cell autofluorescence-a non-invasive imaging technique used to characterise cytometabolic heterogeneity-to identify changes in the autofluorescence signals of MSCs from (1) young mice, (2) old mice, (3) young mice randomised to receive polypharmacy (9-10 weeks of oral therapeutic doses of simvastatin, metoprolol, oxycodone, oxybutynin and citalopram), and (4) old mice randomised to receive polypharmacy. Principal Component Analysis and Logistic Regression Analysis were used to assess alterations in spectral and associated metabolic characteristics. Modelling demonstrated that cells from young mice receiving polypharmacy had less NAD(P)H and increased porphyrin relative to cells from old control mice, allowing for effective separation of the two groups (AUC of ROC curve > 0.94). Similarly, cells from old polypharmacy mice were accurately separated from those from young controls due to lower levels of NAD(P)H (p < 0.001) and higher porphyrin (p < 0.001), allowing for an extremely accurate logistic regression (AUC of ROC curve = 0.99). This polypharmacy regimen may have a more profound impact on MSCs than ageing, and can simultaneously reduce optical redox ratio (ORR) and increase porphyrin levels. This has implications for the use of autologous MSCs for older patients with chronic disease.

Thermoresponsive gating membranes embedded with liquid crystal(s) for pulsatile transdermal drug delivery: An overview and perspectives

Due to the circadian rhythm regulation of almost every biological process in the human body, physiological and biochemical conditions vary considerably over the course of a 24-h period. Thus, optimal drug delivery and therapy should be effectively controlled to achieve the desired therapeutic plasma concentrations and therapeutic drug responses at the required time according to chronopharmacological concepts, rather than continuous maintenance of constant drug concentrations for an extended time period. For many drugs, it is not always necessary to constantly deliver a drug into the human body under disease conditions due to rhythmic variations. Pulsatile drug delivery systems (PDDSs) have been receiving more attention in pharmaceutical development by providing a predetermined lag period, followed by a fast or rate-controlled drug release after application. PDDSs are characterized by a programmed drug release, which may release a drug at repeatable pulses to match the biological and clinical needs of a given disease therapy. This review article focuses on thermoresponsive gating membranes embedded with liquid crystals (LCs) for transdermal drug delivery using PDDS technology. In addition, the principal rationale and the advanced approaches for the use of PDDSs, the marketed products of chronotherapeutic DDSs with pulsatile function designed by various PDDS technologies, pulsatile drug delivery designed with thermoresponsive polymers, challenges and opportunities of transdermal drug delivery, and novel approaches of LC systems for drug delivery are reviewed and discussed. A brief overview of all academic research articles concerning single LC- or binary LC-embedded thermoresponsive membranes with a switchable on-off permeation function through topical application by an external temperature control, which may modulate the dosing interval and administration time according to the therapeutic needs of the human body, is also compiled and presented. In the near future, since thermal-based approaches have become a well-accepted method to enhance transdermal delivery of different water-soluble drugs and macromolecules, a combination of the thermal-assisted approach with thermoresponsive LCs membranes will have the potential to improve PDDS applications but still poses a great challenge.

Treatment of Overactive Bladder in the Elderly Female: The Case for Trospium, Oxybutynin, Fesoterodine and Darifenacin

Overactive bladder (OAB) is a common constellation of lower urinary tract storage symptoms that causes a significant impact on a person's quality of life. The elderly may be disproportionally impacted by these symptoms due to concomitant poor mobility, comorbid conditions such as diabetes and heart failure, and polypharmacy. While behavioral modification and pelvic floor muscle training should be considered first-line treatment options, pharmacotherapy remains the backbone of the therapeutic regimen. Trospium, oxybutynin, fesoterodine, and darifenacin all have unique properties that may confer certain advantages in the elderly population. The hydrophilicity and quaternary amine structure of trospium may limit its ability to cross the blood-brain barrier and thus minimize impact on cognition in the elderly. In its oral form, oxybutynin may have the most significant effect on cognition; however, the transdermal preparations may be favorable in the elderly population due to the ability to avoid first-pass metabolism and its limited antimuscarinic adverse effects. Fesoterodine may be the most extensively studied OAB medication in the elderly population. Darifenacin has a strong affinity for the M3 receptor in the bladder, while having a weak affinity for the M1 receptor commonly found in the brain. It must be noted that all muscarinic receptor antagonists are associated with common adverse effects to some degree, and frequent re-evaluation of the elderly patient is necessary to confirm the proper benefit-to-risk profile.

Single center experience with oxybutynin transdermal system (patch) for management of symptoms related to non-neuropathic overactive bladder in children: an attractive, well tolerated alternative form of administration

OBJECTIVE

Oxybutynin is the current gold standard drug for management of overactive bladder (OAB) in children, but can have significant side effects or be difficult to administer in multiple daily doses. Herein, we report our experience with transdermal oxybutynin patch (TOP) as an alternative in a selected patient population without neuropathic compromise.

MATERIALS AND METHODS

Consecutive patients assessed in a pediatric urology clinic over a 1-year period, diagnosed with OAB with minimum follow-up of 3 months, were included. TOP starting dose was 3.9 mg/day based on product design (Oxytrol). Demographics and outcomes data were retrospectively collected. Symptomatic response was defined as improvement or resolution of lower urinary tract symptoms.

RESULTS

35 children met inclusion criteria (mean age 8 years, range 4-16). Overall, 97% reported good symptom response. The main side effect was skin irritation at TOP site (35%), leading to discontinuation in 20%. There were no reports of other significant side effects. Mean bladder capacity increased from 104 ml to 148 ml at follow-up.

CONCLUSIONS

Our data suggest that TOP is a viable alternative for children with non-neuropathic OAB who do not tolerate other formulations of oxybutynin. These findings highlight the potential benefit of transdermal drug delivery in the pediatric setting.

Management of mixed urinary incontinence

Mixed urinary incontinence accounts for 33% of all incontinence and is the involuntary loss of urine associated with the sensation of urgency; it is also associated with exertion, sneezing or coughing. Risk factors include vaginal delivery, obesity, age and possible genetic factors. Treatment includes lifestyle changes, behavioral therapies, medication and nerve modulation. Surgery with midurethral slings can cure both stress and urge components in 40-50% of cases. Future therapies may include new medications adapting potassium and calcium channels and more widespread use of sacral neuromodulation. This review focuses on the investigation and optimal management of mixed urinary incontinence.

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.

An overview of the clinical use of antimuscarinics in the treatment of overactive bladder

Overactive bladder is a common and bothersome condition. Antimuscarinic agents, as a class, are the cornerstone of medical treatment of overactive bladder. They offer significant improvements in symptoms and patients' quality of life. Antimuscarinics are generally well tolerated with mild and predictable side effects. Available antimuscarinics have small, yet statistically significant, differences in their efficacy and tolerability profiles. In clinical practice, finding the agent that offers the optimum balance of efficacy and side effects for an individual patient remains the major challenge.

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.

Disposition and antimuscarinic effects of the urinary bladder spasmolytics propiverine: influence of dosage forms and circadian-time rhythms

Propiverine extended release is expected to be better tolerated compared to immediate release tablets because of slower drug release and reduced formation of active metabolites in the colon. CYP3A4 and ABCC2, the major variables in pharmacokinetics of propiverine, are less expressed in the colon. Therefore, disposition and pharmacodynamics of propiverine were measured in a double-blind, double-dummy, crossover study with administration of 15 mg immediate release 3 times daily for 7 days compared to 45 mg extended release once daily for 7 days in 24 healthy subjects. Twelve subjects also received 15 mg propiverine intravenously. Serum and urine propiverine levels were measured repeatedly following oral administration on day 7 for up to 72 hours and correlated to duodenal expression of CYP3A4, ABCB1, and ABCC2. Propiverine immediate release 3 times daily was not different to extended release once daily in areas under the serum concentration-time curve (0-24 hours) and peak-trough fluctuation. The areas under the serum concentration-time curve of propiverine immediate release was circadian-time-dependent, with the lowest values during the night. Disposition of intravenous propiverine and propiverine immediate release administered in the night was influenced by intestinal expression of ABCC2. We concluded that oral absorption of propiverine is site-dependent and influenced by dosage form and circadian-time-dependent elimination processes.

New Options and Strategies for the Treatment of Urinary Incontinence

Urinary incontinence is a prevalent, although often unreported, disease within the elderly population, with consequences spanning many aspects of the patient's life. Treatments differ for each subtype of urinary incontinence: urge incontinence, stress incontinence, and incontinence associated with bladder outlet obstruction and lower urinary tract symptoms in men. Limitations in current therapies have negatively affected care for each of these subtypes, particularly in the vulnerable elderly population. An emergence of new treatment options and strategies has created opportunities to optimize care for the general population. These include the use of trospium, darifenacin, solifenacin, and duloxetine as well as the strategic use of antimuscarinic agents in conjunction with alpha adrenergic blockade in men with bladder outlet obstruction. Yet, the literature regarding use of these agents and strategies in the elderly should be carefully evaluated to determine the benefits and the unique risks posed by their use in this vulnerable population.

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.

Pharmacologic management of overactive bladder: practical options for the primary care physician

Overactive bladder (OAB) affects millions of people in the United States and is associated with poor health, impaired quality of life, social isolation, and depressive symptoms. Despite the high prevalence of this syndrome, studies show that it is not adequately addressed by the busy primary care physician, who may be preoccupied with management of other chronic diseases perceived as more serious such as heart disease, diabetes mellitus, and hypertension. Pharmacologic flexible-dosing studies with anticholinergic agents offer a relatively simple strategy for optimal management of OAB: physician-initiated, patient-managed dose adjustment. Recent flexible-dosing studies with extended-release oxybutynin, darifenacin, and solifenacin suggest that urge urinary and total incontinence episodes may be reduced significantly with a flexible-dosing strategy. Dose adjustment may improve the therapeutic outcome, facilitating a balance between efficacy and anticholinergic side effects such as dry mouth. Flexible-dosing studies indicate that dry mouth, the adverse effect most frequently seen with the use of anticholinergic agents, seldom leads to study withdrawal. Patient-initiated control of OAB symptoms may be achieved in 1 month by following established protocols.

Drug delivery systems improve pharmaceutical profile and facilitate medication adherence

Innovations in dosage forms and dose delivery systems across a wide range of medications offer substantial clinical advantages, including reduced dosing frequency and improved patient adherence; minimized fluctuation of drug concentrations and maintenance of blood levels within a desired range; localized drug delivery; and the potential for reduced adverse effects and increased safety. The advent of new large-molecule drugs for previously untreatable or only partially treatable diseases is stimulating the development of suitable delivery systems for these agents. Although advanced formulations may be more expensive than conventional dosage forms, they often have a more favorable pharmacologic profile and can be cost-effective. Inclusion of these dosage forms on drug formulary lists may help patients remain on therapy and reduce the economic and social burden of care.

Effect of the ATP-sensitive potassium channel opener ZM226600 on cystometric parameters in rats with ligature-intact, partial urethral obstruction

The activity of a recent K(ATP) channel opener, the N-(4-Phenylsulfonylphenyl)-3,3,3-trifluoro-2-hydroxy-2-methylpropionamide (ZM226600) was investigated on a female rat model of overactive bladder with outlet obstruction. Both ZM226600 and pinacidil instilled into the bladder (10(-7) M, 30 min) or following systemic administration (10, 100 nmol/kg e.v.) almost completely abolished bladder overactivity and improved residual volume and frequency of micturition. However, pinacidil affected arterial pressure. Oxybutynin instilled into the bladder (10(-7), 10(-6), 10(-5) M, 30 min) decreased detrusor overactivity by about 16%, 25% and 46% respectively, but also blocked micturition reflexes at highest doses tested. Oxybutynin reduced detrusor overactivity by about 50% and 80%, after systemic administration (10, 100 nmol/kg e.v.), but also blocked micturition reflexes at the highest dose tested. In conclusion, ZM226600 is more active than oxybutynin in reducing bladder overactivity, and it is devoid of vascular side effects observed with pinacidil. Its short duration of action (about 1 h) is probably the main problem to solve, in order to consider this compound a valid alternative to antimuscarinics in the therapy of bladder overactivity.

Overactive Bladder in the Elderly

Overactive bladder (OAB) is a common condition characterised by the symptoms of urinary frequency and urgency, with or without urge incontinence and nocturia. The prevalence of OAB increases markedly with age in both men and women. OAB can have a detrimental effect on physical functioning and psychological well-being, as well as significantly reducing quality of life. Antimuscarinic therapy -- with or without behavioural therapy -- represents the most common treatment for patients with OAB. Several antimuscarinic agents are currently available for the treatment of OAB in adults, including oxybutynin, tolterodine, trospium chloride, darifenacin and solifenacin. The antimuscarinics all appear to exert their clinical effect through inhibition of the bladder muscarinic receptors, but they vary both in structure and in their functional profile. While efficacy has been demonstrated in adult populations (including patients >65 years of age), few studies have been reported specifically in a geriatric population, and antimuscarinics are often underutilised in the elderly despite the marked increase in the prevalence of OAB in this age group. One explanation for this apparent underuse of an effective treatment option may be concerns about the frequency of anticholinergic adverse events, such as dry mouth; the likelihood of detrimental CNS effects, including cognitive impairment and sleep disturbances; and the potential for harmful interactions with existing pharmacotherapy. When selecting an antimuscarinic agent for the management of an elderly patient presenting with OAB, in addition to considering evidence of clinical efficacy and tolerability, issues of safety specific to an older population should be borne in mind. In particular, the likelihood of detrimental CNS effects should be considered, including cognitive impairment and sleep disturbances, secondary to anticholinergic load. Oxybutynin and tolterodine have both been associated with cognitive adverse events and effects on sleep architecture and quality. In contrast, trospium chloride and darifenacin do not appear to be associated with cognitive adverse events and trospium chloride does not negatively affect sleep architecture or quality. Biotransformation by the cytochrome P450 (CYP450) system is an important step in the activation or elimination of a large number of drugs, including oxybutynin, tolterodine, darifenacin and solifenacin, raising the possibility of clinically relevant and potentially serious drug interactions. In elderly patients, such interactions are of particular relevance given the potential for declining activity of certain members of the CYP450 family combined with decreased hepatic blood flow, which can reduce first-pass metabolism and thus the bioavailability of drugs metabolised via this route. Of the antimuscarinic agents used to treat OAB, only trospium chloride is not extensively metabolised in the liver by the CYP450 system and is excreted largely as the active parent compound in the urine. This paper provides an overview of the pathophysiology of OAB and reviews current approaches to achieving a differential diagnosis and selecting appropriate treatment for the older patient. The pharmacology and clinical effects of current medication for the treatment of OAB symptoms in patients defined by the OAB pharmacology literature as 'elderly' are also reviewed.