Oxybutynin Extended Release and Tolterodine Immediate Release

Urox containing concentrated extracts of Crataeva nurvala stem bark, Equisetum arvense stem and Lindera aggregata root, in the treatment of symptoms of overactive bladder and urinary incontinence: a phase 2, randomised, double-blind placebo controlled trial

Background

Storage lower urinary tract symptoms (LUTS) including overactive bladder (OAB) and urinary incontinence (UI) affect millions of people worldwide, significantly impacting quality of life. Plant based medicines have been documented both empirically and in emerging scientific research to have varying benefits in reducing bladder symptoms. We assessed the efficacy of Urox®, a proprietary combination of phytomedicine extracts including, Cratevox™ (Crataeva nurvala) stem bark, Equisetem arvense stem and Lindera aggregata root, in reducing symptoms of OAB and UI.

Methods

Efficacy of the herbal combination on a variety of bladder symptoms compared to an identical placebo, were documented in a randomised, double-blind, placebo controlled trial conducted at two primary care centres. Data were collected at baseline, 2, 4 and 8 weeks, with the primary outcome being self-reported urinary frequency. Statistical analysis included mixed effects ordered logistic regression with post hoc Holm’s test to account for repeated measures, and included an intention-to-treat analysis.

Results

One hundred and fifty participants (59% female, aged; mean ± SD; 63.5 ± 13.1 years) took part in the study. At week 8, urinary day frequency was significantly lower (OR 0.01; 95%CI 0.01 to 0.02; p < 0.001) in response to treatment (mean ± SD; 7.69 ± 2.15/day) compared to placebo (10.95 ± 2.47/day). Similarly, episodes of nocturia were significantly fewer (OR 0.03; 95%CI 0.02 to 0.05) after 8 weeks of treatment (2.16 ± 1.49/night) versus placebo (3.14 ± 1.36/night). Symptoms of urgency (OR 0.02; 95%CI 0.01 to 0.03), and total incontinence (OR 0.03; 95% CI 0.01 to 0.06) were also lower (all p < 0.01) in the treatment group. Significant improvements in quality of life were reported after treatment in comparison to placebo. No significant side effects were observed resulting in withdrawal from treatment.

Conclusions

The outcome of this study demonstrated both statistical significance and clinical relevance in reducing symptoms of OAB, urinary frequency and/or urgency and incontinence. The demonstrated viability of the herbal combination to serve as an effective treatment, with minimal side-effects, warrants further longer term research and consideration by clinicians.

Trial registration

NCT02396160 (registered on 17 March 2015 - before any statistical analyses commenced).

Cost effectiveness of mirabegron compared with tolterodine extended release for the treatment of adults with overactive bladder in the United Kingdom

BACKGROUND

Overactive bladder (OAB) is highly prevalent and is associated with considerable morbidity and reduced health-related quality of life. β3-adrenergic receptor (β3-AR) stimulation is a novel alternative to antimuscarinic therapy for OAB.

OBJECTIVE

The objective of this analysis was to assess the cost effectiveness of the β3-AR agonist mirabegron relative to tolterodine extended release (ER) in patients with OAB from a UK National Health Service (NHS) perspective.

METHODS

A Markov model was developed to simulate the management, course of disease, and effect of complications in OAB patients over a period of 5 years. Transition probabilities for symptom severity levels and probabilities of adverse events were estimated from the results of the randomised, double-blind SCORPIO trial in 1,987 patients with OAB. Other model inputs were derived from the literature and on assumptions based on clinical experience.

RESULTS

Total 5-year costs per patient were £1,645.62 for mirabegron 50 mg/day and £1,607.75 for tolterodine ER 4 mg/day. Mirabegron was associated with a gain of 0.009 quality-adjusted life-years (QALYs) with an additional cost of £37.88. The resulting incremental cost-effectiveness ratio (ICER) was £4,386/QALY gained. In deterministic sensitivity analyses in the general OAB population and several subgroups, ICERs remained below the generally accepted willingness-to-pay (WTP) threshold of £20,000/QALY gained. The probability of mirabegron 50 mg being cost effective relative to tolterodine ER 4 mg was 89.4 % at the same WTP threshold.

CONCLUSIONS

Mirabegron 50 mg/day is likely to be cost effective compared with tolterodine ER 4 mg/day for adult patients with OAB from a UK NHS perspective.

The cost-effectiveness of solifenacin vs fesoterodine, oxybutynin immediate-release, propiverine, tolterodine extended-release and tolterodine immediate-release in the treatment of patients with overactive bladder in the UK National Health Service

OBJECTIVE

To assess the cost-effectiveness of solifenacin vs other antimuscarinic strategies commonly used in UK clinical practice, based on the results of a recent published review.

METHODS

Overactive bladder (OAB) syndrome is characterized by symptoms of urgency, frequency, incontinence and nocturia. Pharmacological treatment comprises oral antimuscarinic agents, which are divided into older-generation treatments, including oxybutynin, and new-generation treatments, comprising solifenacin, tolterodine, darifenacin and fesoterodine. The latter have reduced central nervous system penetration and have better selectivity for the M3 subclass of acetylcholine receptors, resulting in improved tolerability. A recent systematic review and meta-analysis of the efficacy and safety of antimuscarinics provided an opportunity for an economic evaluation of these agents using a rigorous assessment of efficacy. A cost-utility analysis was undertaken using a 1-year decision-tree model. Treatment success was defined separately for urgency, frequency and incontinence, with efficacy data taken from the recent review. Treatment persistence rates were taken from the Information Management System database. Utility values for the calculation of quality-adjusted life-years (QALYs) were taken from published sources. The analysis included costs directly associated with treatment for OAB, i.e. antimuscarinic therapy, consultations with general practitioners, and outpatient contacts. Resource use was based on expert opinion. Costs were reported at 2007/2008 prices. Extensive deterministic and probabilistic analyses were conducted to test the robustness of the base-case results.

RESULTS

Solifenacin was associated with the highest QALY gains (per 1000 patients) for all three outcomes of interest, i.e. urgency (712.3), frequency (723.1) and incontinence (695.0). Solifenacin was dominant relative to fesoterodine, tolterodine extended-release (ER) and tolterodine immediate-release (IR), and cost-effective relative to propiverine ER for urgency, frequency and incontinence. Solifenacin was not found to be cost-effective relative to oxybutynin IR for the frequency and incontinence outcomes, with an incremental cost-effectiveness ratio of > pound30,000/QALY threshold.

CONCLUSIONS

Solifenacin provided the greatest clinical benefit and associated QALYs for all three outcomes of interest across all therapies considered, and to be either dominant or cost-effective relative to all other new-generation agents, but not cost-effective relative to oxybutynin for frequency and incontinence.

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.

Outcomes associated with pharmacotherapy in overactive bladder

Overactive bladder is one of the most prevalent medical conditions in the USA. Prevalence rates of overactive bladder are higher in women and increase with advanced age. Although the disease is not associated with mortality, it has significant impact on health-related quality of life amongst patients. Pharmacologic, as well as behavioral treatment therapies, are available for overactive bladder treatment with pharmacologic agents being the mainstay therapy. The purpose of this review is to outline the recent developments in the treatment of overactive bladder. This is an extensive review that provides important information on the outcomes associated with different pharmacotherapeutic agents used in overactive bladder. It concludes with the authors' opinions and suggestions for the future research in this area.

Pharmacological management of overactive bladder : a systematic and critical review of published economic evaluations

Overactive bladder is a common condition, with recent findings estimating the prevalence in adults at about 15%. Symptoms, including urinary urgency, high voiding frequency and urge incontinence, have been shown to decrease patients' quality of life. Given its high prevalence, the economic burden of overactive bladder is also substantial, with a recent estimate placing the annual cost in the US at 9.1 billion US dollars (year 2000 values). The objective of this review is to provide a critical appraisal of published economic evaluations of pharmacological and non-pharmacological treatments for overactive bladder. Published economic evaluations of treatments for overactive bladder have focused entirely on pharmacological treatments -- mainly on the two most commonly used drugs, oxybutynin and tolterodine, each of which is available in immediate- and extended-release formulations. Ten economic evaluations (more than half are cost-effectiveness studies) have been published. Modelling with decision trees or Markov models has been the predominant method. Evaluations comparing drug therapy with no treatment have concluded that drug therapy is cost effective. Analyses comparing the formulations of oxybutynin and tolterodine have produced highly inconsistent results, largely due to the sources of data employed for effectiveness and treatment discontinuation rates. There are no evaluations of drugs relative to non-pharmacological treatment, and there are other significant gaps in the economic evaluations of treatment to date. These include gaps resulting from a lack of reliable data on the performance of these drugs in real-world settings, particularly data on long-term persistence with treatment. A more definitive pharmacoeconomic comparison of oxybutynin and tolterodine formulations, incorporating all available clinical data, and other treatment options would help direct treatment.