Efficacy and safety of imidafenacin for overactive bladder in adult: a systematic review and meta-analysis

Muscarinic control of cardiovascular function in humans: a review of current clinical evidence

PURPOSE

To review the available evidence on the impact of muscarinic receptor modulation on cardiovascular control in humans.

METHODS

In this narrative Review we summarize data on cardiovascular endpoints from clinical trials of novel subtype-selective or quasi-selective muscarinic modulators, mostly PAMs, performed in the last decade. We also review the cardiovascular phenotype in recently described human genetic and autoimmune disorders affecting muscarinic receptors.

RESULTS

Recent advancements in the development of compounds that selectively target muscarinic acetylcholine receptors are expanding our knowledge about the physiological function of each muscarinic receptor subtype (M1, M2, M3, M4, M5). Among these novel compounds, positive allosteric modulators (PAMs) have emerged as the preferred therapeutic to regulate muscarinic receptor subtype function. Many muscarinic allosteric and orthosteric modulators (including but not limited to xanomeline-trospium and emraclidine) are now in clinical development and approaching regulatory approval for multiple indications, including the treatment of cognitive and psychiatric symptoms in patients with schizophrenia as well as Alzheimer's disease and other dementias. The results of these clinical trials provide an opportunity to understand the influence of muscarinic modulation on cardiovascular autonomic control in humans. While the results and the impact of each of these therapies on heart rate and blood pressure control have been variable, in part because the clinical trials were not specifically designed to measure cardiovascular endpoints, the emerging data is valuable to elucidate the relative cardiovascular contributions of each muscarinic receptor subtype.

CONCLUSION

Understanding the muscarinic control of cardiovascular function is of paramount importance and may contribute to the development of novel therapeutic strategies for treating cardiovascular disease.

Comparison of add-on medications for persistent storage symptoms after α-blocker treatment in BPH patients - a network meta-analysis

BACKGROUND

Patients with benign prostatic hyperplasia (BPH) receive α-blockers as first-line therapy to treat lower urinary tract symptoms; however, some individuals still experience residual storage symptoms. Antimuscarinics, β3-agonists, and desmopressin are effective add-on medications. Nevertheless, there is currently no evidence for the appropriate choice of the first add-on medication. This systematic review aimed to investigate the clinical benefits of antimuscarinics, β3-agonists, and desmopressin, in addition to α-blockers, for persistent storage symptoms in BPH patients.

METHODS

A comprehensive literature search of randomized controlled trials (RCTs) comparing the efficacy of different add-on medications in BPH patients with persistent storage symptoms despite α-blocker treatment was conducted. Clinical outcomes included the International Prostate Symptom Score (IPSS), IPSS storage subscore, nocturia, micturition, and urgency. A network meta-analysis was performed to estimate the effect size. Surface under cumulative ranking curves (SUCRAs) were used to rank the included treatments for each outcome.

RESULTS

A total of 15 RCTs were identified. Add-on imidafenacin and mirabegron resulted in significant improvement in all outcomes assessed. Other add-on medications such as desmopressin, tolterodine, solifenacin, fesoterodine, and propiverine showed positive benefits for most, but not all, outcomes. Based on the SUCRA rankings, add-on desmopressin was the best-ranked treatment for IPSS and nocturia, and add-on imidafenacin was the best for the IPSS storage subscore and micturition.

CONCLUSIONS

BPH patients presenting with persistent storage symptoms despite α-blocker administration are recommended to include additional treatment. Desmopressin and imidafenacin may be considered high-priority add-on treatments because of their superior efficacy compared with other medications.

Adherence to Overactive Bladder Syndrome Treatments Recent Developments and Future Perspectives

Overactive bladder (OAB) is a common and distressing condition which is known to have a significant effect on Health-Related Quality of Life (HRQoL). Whilst all patients complaining of overactive bladder symptoms will, in theory, initially benefit from conservative measures, many will require pharmacological therapy. Antimuscarinics currently remain the most commonly used drugs to treat OAB although compliance and persistence can be poor due to concerns regarding adverse events and lack of efficacy. This review will explore the common management strategies for OAB with a particular focus on patient adherence to therapy including compliance and persistence. The role of antimuscarinics and the B3-agonist, mirabegron, will be considered along with barriers to their efficacy and adoption. For those patients in whom conservative and pharmacological treatment proves ineffective or is unsuitable, the management of refractory OAB will also be considered. In addition, the role of current and future developments will be examined.

ASSESSMENT OF EFFICIENCY OF COMBINED PHARMACOTHERAPY FOR IMPERATIVE AND MIXED URINARY DISORDERS IN WOMEN WITH THE INTERVAL SCALE

Introduction. The search for effective drug combinations for treating continental disorders in women is still relevant. The interval scale for assessing lower urinary tract symptoms in women is a simple and convenient tool for monitoring pharmacotherapy. Objective: to evaluate the effectiveness of treatment of imperative and mixed urination disorders in women with alpha1-blockers in combination with nootropic drugs using an interval symptom rating scale.Materials and methods. Under observation there were 31 patients aged 40 to 73 years who applied to the Center “Urination Pathology” with mixed and imperative disorders of the continent and urinary incontinence. Conservative therapy was carried out with the appointment of alpha1-adrenoblockers, nootropic and metabolic drugs for an average of 5.8 months. The therapeutic effect is recorded using the interval symptom score scale.Results. After discontinuation of drugs, the overall score on the symptom rating scale decreased by 40.2%, imperative symptoms – by 29.5-50%, and quality of life increased by 19%. In the group of women aged 40-49, with comparable dynamics of symptoms with patients older than 50 years, therapy lasted less. The difference averaged 4.1 months and was associated with a higher frequency in the older age group of vascular, metabolic and neurological disorders that slow down the regulatory processes of urination recovery.Conclusion. Alpha1-blockers and nootropics are pathogenetically substantiated for the treatment of imperative disorders of urination and urinary incontinence. Evaluation using the interval scale reliably demonstrates their high clinical effectiveness, persistence of the therapeutic effect and the feasibility of application at the stage of selection for surgical treatment.

A double-blind, randomized, placebo-controlled, parallel study to evaluate the efficacy and safety of imidafenacin in patients with overactive bladder in Taiwan

OBJECTIVE

This study evaluated the efficacy and safety of imidafenacin 0.1 mg twice daily vs placebo for Taiwanese patients with overactive bladder (OAB) after a 12-week oral administration.

METHODS

This randomized, double-blind, placebo-controlled, two-arm, parallel-group, prospective study enrolled 118 patients across 11 study sites in Taiwan. Subjects were randomized to imidafenacin or placebo in a 2:1 ratio and entered the 12-week treatment period. At the subsequent visits, efficacy outcome measures and safety assessments were collected for analysis. The primary efficacy outcome was the change in the mean number of micturitions per day. Secondary endpoints included mean changes from baseline in urgency episodes and urge incontinence episodes per day and mean volume voided per micturition. Safety outcomes were also collected and compared between groups.

RESULTS

A total of 78 and 40 patients were allocated to the imidafenacin and placebo groups, respectively. Among them, 100 patients (imidafenacin, 65 and placebo, 35) completed the trial. Compared with placebo, imidafenacin was significantly better at reducing the number of micturitions per day (-1.29 ± 2.23 vs -0.46 ± 3.49, P = .0171) and reducing the mean number of urge incontinence episodes (-0.15 ± 0.52 vs 0.04 ± 0.50, P = .0386) at week 12. Adverse events were reported in 35 subjects (44.9%) and 16 (40%) in the imidafenacin and placebo groups, including constipation (n = 3, 4), dry mouth (n = 11, 2), and urinary tract infection (n = 7, 4), respectively. One patient in the imidafenacin group had mild dysuria.

CONCLUSION

Imidafenacin demonstrated efficacy and safety in the treatment of OAB in Taiwanese patients.

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.

Is imidafenacin an alternative to current antimuscarinic drugs for patients with overactive bladder syndrome?

PURPOSE

Previous studies have included a limited number of randomized controlled trials (RCTs) and compared limited parameters after treatment with imidafenacin and other anticholinergic drugs (ADs) for overactive bladder syndrome (OAB), and controversy about the superiority of these ADs still remains. We aim to update the evidence and provide better clinical guidance.

METHODS

A systematic search of PubMed, Embase, ClinicalTrial.gov and Cochrane Library Central Register of Controlled Trials was conducted from January 2007 to April 2019. Meta-analysis of all published RCTs comparing imidafenacin with other ADs in patients with OAB was performed. The primary outcomes were the changes in OAB symptoms and OAB symptom score (OABSS). Secondary outcomes included adverse events (AEs) and the dropout rate related to AEs.

RESULTS

A total of 6 studies including 7 RCTs involving 1430 patients with mean follow-up of 23.43 weeks were included. All ADs improved OAB symptoms. Regarding efficacy, these drugs had similar efficacy in voids, urgency episodes, urgency incontinence episodes, incontinence episodes and OABSS. However, imidafenacin performed better in the reduction of nocturia episodes (MD = -0.24, 95% CI -0.44 to -0.04, P = 0.02). Moreover, imidafenacin was associated with a statistically lower dry mouth rate (RR = 0.87, 95% CI 0.75-1.00, P = 0.04), lower constipation rate (RR = 0.68, 95% CI 0.50-0.93, P = 0.01) and lower AE-related withdrawal rate (RR = 0.51, 95% CI 0.29-0.89, P = 0.02). There was no significant difference in terms of other complications.

CONCLUSIONS

In conclusion, imidafenacin was comparable to other ADs in the treatment of OAB. Moreover, imidafenacin presented a lower dry mouth rate, lower constipation rate and higher adherence and persistence.

Advances in pharmacotherapy for the treatment of overactive bladder

Purpose of review

To present the current literature on the pharmacologic management of overactive bladder, including combination therapies, agents still in clinical development, and special considerations related to individuals with cognitive decline, frailty and cardiovascular risk.

Recent Findings

Combination therapy is shown to be more effective than monotherapy, without additional side effects. Preliminary studies on novel treatment methods, including new medications, as well was novel use of established medications, demonstrates improved efficacy with a favorable side effect profile. Investigation into new target pathways may be an area for future pharmacologic development. Special consideration should be given when prescribing anti-muscarinic medication in the frail adult population. Overactive bladder has been associated with frailty and anti-muscarinic medications have been associated with the worsening cognitive decline.

Summary

Combination therapy is a safe and effective alternative to patients with refractory overactive bladder. Caution should be taken in prescribing medications for the frail older adult, and alternative first- and third-line treatments should be considered. Future studies should involve long term data on safety and outcomes stratified by age with objective measurements of cognition and frailty.

Randomized, open-label, tolterodine-controlled, comparative study of the novel antimuscarinic agent imidafenacin in patients with overactive bladder

BACKGROUND

The role of the selective antimuscarinic imidafenacin in Caucasian patients with overactive bladder (OAB) has not been previously assessed.

OBJECTIVE

To evaluate the safety and efficacy of imidafenacin 0.2 mg vs tolterodine 4 mg per day in patients with OAB.

DESIGN SETTING AND PARTICIPANTS

This study was a randomized, open-label, tolterodine-controlled, comparative multicenter trial of 300 randomized patients with OAB symptoms for 12 weeks with full analysis of 289 patients.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Based on 5-day bladder diaries, the primary efficacy endpoint was the change in the mean number of micturitions per day. The secondary endpoints were the change in the mean incontinence episodes, voiding frequency, the OAB Awareness Tool score, and the European Quality of Life Questionnaire (EQ-5D) score. The superiority of tolterodine over imidafenacin in the mean number of micturitions/24 hours was the null hypothesis.

RESULTS AND LIMITATION

The median age was 46.6 years, and 82% of patients were female. After treatment, the change in the mean number of incontinence episodes was -2.1 ± 2.2 in the imidafenacin group and -1.9 ± 1.8 in the tolterodine group (P = .001). The change in the mean number of daytime incontinence episodes was -1.7 ± 1.7 and -1.5 ± 1.4 ( P = .01). The OAB Awareness Tool score decreased by 14.2 ± 8.5 and 14.5 ± 8.0, respectively ( P = 0.5). Most adverse events were mild and resolved without treatment.

CONCLUSIONS

The clinical efficacy and safety of imidafenacin are not inferior to those of tolterodine for the treatment of Caucasian patients with OAB.

PATIENT SUMMARY

Imidafenacin is as effective as tolterodine for the treatment of OAB.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Novel Extended-Release Multiple-Unit System of Imidafenacin Prepared by Fluid-Bed Coating Technique

The objective of this study was to formulate once-a-day extended-release (ER) pellet system of imidafenacin (IDN), a recently approved urinary antispasmodic agent with twice-a-day dosing regimen. The sugar sphere pellets were firstly layered with IDN and hypromellose and then coated with Eudragit RS (copolymers of acrylic and methacrylic acid esters), employed as a release modifier, using a fluid-bed coater. Solid-state characterizations using solid-state X-ray diffraction and differential scanning calorimeter indicated that the antispasmodic agent was homogeneously layered onto the pellets in an amorphous state. Drug release from multiple-unit ER system was effectively retarded in proportion to the amount of Eudragit RS in the outer layer, with a high correlation value above 0.86. In a pharmacokinetic evaluation in beagle dogs, the plasma concentration profile of IDN was markedly protracted by ER pellets, exhibiting delayed the time needed to reach the maximum drug concentration and the elimination half-life in plasma, compared to the commercial immediate release form (Uritos® tablet, Kyorin Pharmaceutical Co., Ltd., Japan). Therefore, the novel ER pellets can be a promising tool for oral IDN therapy, providing a once-a-day dosing regimen, and thus, improving patient compliance.

Basic and clinical aspects of antimuscarinic agents used to treat overactive bladder

Antimuscarinic agents are now widely used as the pharmacological therapy for overactive bladder (OAB) because neuronal (parasympathetic nerve) and non-neuronal acetylcholine play a significant role for the bladder function. In this review, we will highlight basic and clinical aspects of eight antimuscarinic agents (oxybutynin, propiverine, tolterodine, solifenacin, darifenacin, trospium, imidafenacin, and fesoterodine) clinically used to treat urinary dysfunction in patients with OAB. The basic pharmacological characteristics of these eight antimuscarinic agents include muscarinic receptor subtype selectivity, functional bladder selectivity, and muscarinic receptor binding in the bladder and other tissues. The measurement of drug-receptor binding after oral administration of these agents allows for clearer understanding of bladder selectivity by the integration of pharmacodynamics and pharmacokinetics under in vivo conditions. Their central nervous system (CNS) penetration potentials are also discussed in terms of the feasibility of impairments in memory and cognitive function in elderly patients with OAB. The clinical aspects of efficacy focus on improvements in the daytime urinary frequency, nocturia, bladder capacity, the frequency of urgency, severity of urgency, number of incontinence episodes, OAB symptom score, and quality of life (QOL) score by antimuscarinic agents in patients with OAB. The safety of and adverse events caused by treatments with antimuscarinic agents such as dry mouth, constipation, blurred vision, erythema, fatigue, increased sweating, urinary retention, and CNS adverse events are discussed. A dose-dependent relationship was observed with adverse events, because the risk ratio generally increased with elevations in the drug dose of antimuscarinic agents. Side effect profiles may be additive to or contraindicated by other medications.

A multicenter real-life study of the efficacy of an alpha-blocker with or without anticholinergic agent (imidafenacin) treatment in patients with lower urinary tract symptoms/benign prostatic hyperplasia and storage symptoms

AIMS

To evaluate the efficacy and safety of combination therapy comprising a short-acting anticholinergic, imidafenacin and an alpha-blocker compared with monotherapy with an alpha-blocker only in men with lower urinary tract symptoms (LUTS) and storage symptoms.

METHODS

The 12-week, prospective, double-blind, randomised trial enrolled men with LUTS and storage symptom. The inclusion criteria were a total International Prostate Symptom Score (IPSS) ≥12, an IPSS question 4 score ≥2, ≥8 micturitions in 24 hours, and a prostate volume >20 mL. The primary outcome was a change in the micturition number from baseline. Bladder diary variables, Patient Perception of Intensity of Urgency Scale (PPIUS) scores, IPSS and safety were assessed.

RESULTS

Of 260 patients screened, 221 completed the study. Patients were randomly assigned to receive an alpha-blocker only (n=111, group 1) or combination therapy comprising an alpha-blocker and an anticholinergic (n=110, group 2) for 12 weeks. Group 1 and 2 showed significant improvement in their 24-hour micturition numbers (-1.87 and -2.08, respectively), nocturia episodes (-0.48 and -0.53, respectively), total IPSS (-9.9 and -8.8, respectively), and PPIUS scores (-0.19 and -0.24, respectively). Micturition number per 24 hours, daytime frequency, urgency, the PPIUS score, the IPSS question 4 score and IPSS QoL score improved significantly in the combination therapy group, but changes in total IPSS, nocturia episodes, and safety outcomes did not differ significantly between the groups.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Compared with treatment with an alpha-blocker alone, combination therapy comprising an anticholinergic and an alpha-blocker showed superior efficacy and its safety was similar in patients with LUTS and storage symptoms.

Adverse events and treatment discontinuations of antimuscarinics for the treatment of overactive bladder in older adults: A systematic review and meta-analysis

INTRODUCTION

Antimuscarinics should be used with caution in older adults with overactive bladder (OAB) due to anticholinergic adverse events (AEs). Systematic reviews and meta-analyses (SRMAs) have analyzed safety-related outcomes but have not specified risk in the elderly, the population at highest risk for AEs. The aim of this review is to explore and evaluate AEs and treatment discontinuations in adults 65 or older taking antimuscarinics for OAB.

METHODS

Keywords were searched in MEDLINE, EMBASE, SCOPUS, and Cochrane Central Register for Controlled Trials. Randomized controlled trials (RCTs) along with sub-analyses and pooled analyses that compared antimuscarinics to placebo or another antimuscarinic were performed in February 2015. Studies assessing AEs or treatment discontinuations in a population of adults 65 or older were included. The Jadad Criteria and McHarm Tool were used to assess the quality of the trials.

RESULTS

A total of 16 studies met the inclusion criteria. Eighty AEs and 27 reasons for treatment discontinuation were described in the included studies and further explored. Anticholinergic AEs were more common in antimuscarinics compared to placebo. Incidence of dizziness, dyspepsia, and urinary retention with fesoterodine, headache with darifenacin, and urinary tract infections with solifenacin were significantly higher compared to placebo. Treatment discontinuation due to AEs and dry mouth were higher in the antimuscarinics when compared to placebo in older adults.

CONCLUSIONS

Treatment for overactive bladder using antimuscarinics in adults aged 65 or older resulted in significant increases in risk for several AEs compared to placebo including anticholinergic and non-anticholinergic AEs.

Comparison of mirabegron and imidafenacin for efficacy and safety in Japanese female patients with overactive bladder: A randomized controlled trial (COMFORT study)

OBJECTIVES

To evaluate the efficacy and safety of mirabegron compared with imidafenacin for the treatment of female patients with overactive bladder.

METHODS

Patients (n = 89) were randomized to receive 0.1 mg imidafenacin twice daily (n = 47) or 50 mg mirabegron once daily (n = 42) for 12 weeks. The primary efficacy end-point was change in total Overactive Bladder Symptom Score. Secondary efficacy end-points included change in Overactive Bladder Symptom Score, 3-day micturition diary, International Prostate Symptom Score and Overactive Bladder Questionnaire. Safety assessments included adverse events, vital signs, post-void residual volume and patient-reported incidence, and severity of distinctive symptoms related to adverse events.

RESULTS

The mirabegron group showed a significantly reduced mean total Overactive Bladder Symptom Score from baseline, but no significant differences were noted in change of total Overactive Bladder Symptom Score compared with the imidafenacin group. Significant improvements in secondary efficacy end-points were observed regarding the mean number of micturitions/24 h, mean number of urgency episodes/24 h, mean number of incontinence episodes/24 h, mean volume voided/micturition, total International Prostate Symptom Score and quality of life in both groups, with no significant differences between the groups. The overall incidence of adverse events and the incidence of dry mouth were significantly higher in the imidafenacin group than in the mirabegron group. Patient-reported incidence and the severity of dry mouth were significantly exacerbated in the imidafenacin group.

CONCLUSIONS

Treatment with 50 mg mirabegron once daily effectively relieves overactive bladder symptoms in women with fewer adverse events than treatment with antimuscarinics.

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.