Long-term safety, efficacy, and tolerability of imidafenacin in the treatment of overactive bladder: a review of the Japanese literature

Cognitive effects of individual anticholinergic drugs: a systematic review and meta-analysis

Anticholinergics (ACs) are among the most prescribed drugs. Investigating the impaired cognitive domains due to individual ACs usage is associated with controversial findings.

Objective

The objective of this study was to investigate the effects of individual ACs on different aspects of cognitive function based on clinical trial studies.

Methods

This systematic review was conducted following the PRISMA statement. A systematic search was performed in Embase, PubMed, Cochrane Library, Scopus, and Web of Science databases. Risk of bias (RoB) was assessed by the Joanna Briggs Institute checklists and the meta-analysis was performed using the CMA software.

Results

Out of 3,026 results of searching, 138 studies were included. A total of 38 studies that assess the cognitive impacts of scopolamine were included in the meta-analysis. Included studies reported cognitive effects of scopolamine, mecamylamine, atropine, biperiden, oxybutynin, trihexyphenidyl, benzhexol, and dicyclomine; however, glycopyrrolate, trospium, tolterodine, darifenacin, fesoterodine, tiotropium, and ipratropium were not associated with cognitive decline. Based on the meta-analyses, scopolamine was associated with reduced recognition (SDM -1.84; 95%CI -2.48 to -1.21; p<0.01), immediate recall (SDM -1.82; 95%CI -2.35 to -1.30; p<0.01), matching to sample (SDM -1.76; 95%CI -2.57 to -0.96; p<0.01), delayed recall (SDM -1.54; 95%CI -1.97 to -1.10; p<0.01), complex memory tasks (SDM -1.31; 95%CI -1.78 to -0.84; p<0.01), free recall (SDM -1.18; 95%CI -1.63 to -0.73; p<0.01), cognitive function (SDM -0.95; 95%CI -1.46 to -0.44; p<0.01), attention (SDM -0.85; 95%CI -1.38 to -0.33; p<0.01), and digit span (SDM -0.65; 95%CI -1.21 to -0.10; p=0.02). There was a high RoB in our included study, especially in terms of dealing with possible cofounders.

Conclusion

The limitations of this study suggest a need for more well-designed studies with a longer duration of follow-up on this topic to reach more reliable evidence.

Long-term efficacy and safety of vibegron versus mirabegron and anticholinergics for overactive bladder: a systematic review and network meta-analysis

Background

Few randomized controlled trials evaluate the long-term efficacy and safety of pharmacotherapy for overactive bladder (OAB). This network meta- analysis compares the long-term (52-week) efficacy and safety of vibegron, mirabegron and anticholinergics for the treatment of OAB.

Methods

A systematic literature review and network meta-analysis were conducted following PRISMA guidelines using MEDLINE, Embase and Cochrane Central Register of Controlled Trials and terms related to OAB. Efficacy outcomes included change from baseline to week 48-52 in mean daily total urinary incontinence (UI) episodes, mean daily number of micturitions and volume voided/micturition. Efficacy outcomes were analysed using Bayesian models. Commonly reported adverse events (AEs) are described.

Results

Of 2098 hits retrieved, 5 publications and 1 study report describing 5 unique randomized controlled trials were included in the analyses. Mean (95% credible interval) change from baseline in total UI episodes for vibegron 75 mg (-2.2; -2.9 to -1.5) showed a significantly greater reduction than mirabegron 50 mg (-1.3; -1.9 to -0.8) and tolterodine 4 mg extended release (-1.6; -2.1 to -1.1). No significant differences were observed between vibegron and comparators for daily micturitions or volume voided/micturition. Within the manuscripts, the 4 most common AEs (range) for anticholinergics included dry mouth (5.2-90.0%), constipation (7.7-65.0%), blurred vision (3.8-35.0%) and hypertension (8.6-9.6%); the 4 most commonly reported AEs for β3-adrenergic agonists included hypertension (8.8-9.2%), urinary tract infection (5.9-6.6%), headache (5.5%) and nasopharyngitis (4.8-5.2%).

Conclusion

Vibegron was associated with significantly greater improvement in daily total UI episodes at 52 weeks than mirabegron and tolterodine. When reported, the most common AE for anticholinergics was dry mouth and for β3-adrenergic agonists was hypertension. Hypertension incidence was similar between drug classes.

Imidafenacin, An Orally Active Muscarinic Receptor Antagonist, Improves Pulmonary Function In Patients With Chronic Obstructive Pulmonary Disease: A Multicenter, Randomized, Double-Blind, Placebo-Controlled 3×3 Crossover Phase II Trial

Background

Although long-acting muscarinic receptor antagonists are central to the management of chronic obstructive pulmonary disease (COPD), inhaled medicines may have technical difficulty in some patients and adherence barriers.

Methods

A multicenter, randomized, double-blind, placebo-controlled 3×3 crossover Phase II trial was performed to evaluate the efficacy and safety of oral administration of the antimuscarinic agent imidafenacin in patients with COPD. Twenty-seven male COPD patients with % forced expiratory volume in 1 s (FEV₁) ≥30% and <80% predicted were randomized to single oral dose of imidafenacin 0.1 mg, imidafenacin 0.2 mg, or placebo.

Results

Maximum change in FEV₁ with both doses of imidafenacin significantly improved from baseline to 24 hrs after administration when compared with a placebo. Area under the curve in FEV₁ during 24 hrs after administration with 0.2 mg, but not 0.1 mg dose, was significantly improved when compared with a placebo, and the improvement was significantly based on dose-dependent manners. Plasma imidafenacin level was positively correlated with change in FEV₁. All subjects with both doses of imidafenacin completed without moderate nor severe adverse events.

Conclusion

A single oral dose of imidafenacin 0.1 mg or imidafenacin 0.2 mg may contribute to the improvement of pulmonary function with excellent safety and tolerability in patients with COPD.

Trial registration

JapicCTI-121760 (Japan Pharmaceutical Information Center – Clinical Trials Information [JapicCTI]; http://www.clinicaltrials.jp/user/cteSearch_e.jsp).

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.

Acetylcholinesterase Inhibitors and Drugs Acting on Muscarinic Receptors- Potential Crosstalk of Cholinergic Mechanisms During Pharmacological Treatment

BACKGROUND

Pharmaceuticals with targets in the cholinergic transmission have been used for decades and are still fundamental treatments in many diseases and conditions today. Both the transmission and the effects of the somatomotoric and the parasympathetic nervous systems may be targeted by such treatments. Irrespective of the knowledge that the effects of neuronal signalling in the nervous systems may include a number of different receptor subtypes of both the nicotinic and the muscarinic receptors, this complexity is generally overlooked when assessing the mechanisms of action of pharmaceuticals.

METHODS

We have search of bibliographic databases for peer-reviewed research literature focused on the cholinergic system. Also, we have taken advantage of our expertise in this field to deduce the conclusions of this study.

RESULTS

Presently, the life cycle of acetylcholine, muscarinic receptors and their effects are reviewed in the major organ systems of the body. Neuronal and non-neuronal sources of acetylcholine are elucidated. Examples of pharmaceuticals, in particular cholinesterase inhibitors, affecting these systems are discussed. The review focuses on salivary glands, the respiratory tract and the lower urinary tract, since the complexity of the interplay of different muscarinic receptor subtypes is of significance for physiological, pharmacological and toxicological effects in these organs.

CONCLUSION

Most pharmaceuticals targeting muscarinic receptors are employed at such large doses that no selectivity can be expected. However, some differences in the adverse effect profile of muscarinic antagonists may still be explained by the variation of expression of muscarinic receptor subtypes in different organs. However, a complex pattern of interactions between muscarinic receptor subtypes occurs and needs to be considered when searching for selective pharmaceuticals. In the development of new entities for the treatment of for instance pesticide intoxication, the muscarinic receptor selectivity needs to be considered. Reactivators generally have a muscarinic M2 receptor acting profile. Such a blockade may engrave the situation since it may enlarge the effect of the muscarinic M3 receptor effect. This may explain why respiratory arrest is the major cause for deaths by esterase blocking.

Imidafenacin exerts the antidiuretic effect by enhancing vasopressin-related responses in orally water-loaded rats

Imidafenacin, an antimuscarinic agent for treating overactive bladder, has an antidiuretic effect, but the detailed mechanisms of action remain unclear. The cholinergic and vasopressin systems are known to interact, for example, in the suppression of vasopressin-induced water reabsorption through muscarinic stimulation in the renal collecting duct. We, therefore, investigated whether vasopressin signaling pathway would participate in the antidiuretic effect of imidafenacin. In female Sprague-Dawley rats, urine production was measured by collecting urine from cystostomy chatheter using a Bollman restraining cage for 2h after drug i.v. injection and water load (25ml/kg p.o.). Both imidafenacin and a vasopressin V₂ receptor agonist desmopressin acetate (desmopressin) dose-dependently suppressed urine production. The combination of imidafenacin and desmopressin at the minimum effective doses suppressed the urine production more strongly than each alone. Mozavaptan hydrochloride (mozavaptan, 3mg/kg), a vasopressin V₂ receptor antagonist, completely inhibited the antidiuretic effects of imidafenacin and desmopressin at their respective minimum effective doses. The antidiuretic effect of desmopressin emerged at the maximum antidiuretic dose level (0.1µg/kg) even under mozavaptan-treatment, whereas that of imidafenacin (300µg/kg) was still kept suppressed by mozavaptan. When 300µg/kg imidafenacin was added to the combination of mozavaptan 3mg/kg and desmopressin 0.1µg/kg, the antidiuretic effect was further enhanced. The present study suggests that vasopressin signaling pathway participates in the antidiuretic effect of imidafenacin, and that imidafenacin exerts its antidiuretic effects by enhancing some part of the vasopressin signaling pathway in orally water-loaded rats.

Characterization of muscarinic receptor binding by the novel radioligand, [(3)H]imidafenacin, in the bladder and other tissues of rats

The present study aimed to directly characterize specific binding sites of tritium ([(3)H])-labeled imidafenacin, a new radioligand for labeling muscarinic receptors, in the bladder and other peripheral or central nervous tissues of rats. Muscarinic receptors in rat tissues were measured by radioligand binding assay using [(3)H]imidafenacin. Specific [(3)H]imidafenacin binding in rat tissues was saturable, reversible, and of high affinity. Estimated dissociation constants (Kd values) were significantly lower in submaxillary gland and prostate and higher in heart than in bladder, indicating lower Kd values in M1 and M3 subtype- than M2 subtype-dominating tissues. Unlabeled imidafenacin and clinically used antimuscarinic agents competed with [(3)H]imidafenacin for binding sites in bladder and other tissues in a concentration-dependent manner, which indicated pharmacological specificity of [(3)H]imidafenacin binding sites. Pretreatment with N-(2-chloroethyl)-4-piperidinyl diphenylacetate (4-DAMP mustard), an irreversible inactivating agent of M3 subtype, significantly decreased the number of [(3)H]imidafenacin binding sites in bladder, submaxillary gland, and colon, but not in heart. [(3)H]imidafenacin labeled muscarinic receptors in M1 and M3 subtype-dominating tissues with higher affinity than [N-methyl-(3)H]scopolamine methyl chloride (NMS). [(3)H]imidafenacin is a useful radioligand to label muscarinic receptors in M1- and M3-dominating tissues with high affinity.

Comprehensive Health-Related Quality of Life is Influenced by Nocturia and Sleep Disturbance: Investigation Based on the SF-8

We investigated the influence of nocturia and sleep disturbance on health-related quality of life(HRQOL) using the Medical Outcomes Study 8-item Short Form Health Survey (SF-8) in patients with nocturia. We also assessed the effect of therapeutic intervention by means of an anticholinergic agent on the results of the SF-8. One hundred and eighty-four patients who voided at least once per night were surveyed using the SF-8, Overactive Bladder Symptom Score (OABSS), Pittsburgh Sleep Quality Index (PSQI), and Epworth Sleepiness Scale (ESS). These parameters were also evaluated before and after 12 weeks of imidafenacin treatment in 51 patients with OAB accompanied by nocturia. The SF-8 physical component summary score (PCS) showed a significant decrease as nighttime voiding frequency increased. The mental health component summary score was 47.1 and 47.6 (which were lower than the standard value of 50) in the group with a nighttime frequency of once and ≥3/night, respectively. The SF-8 PCS and 6 subscales were negatively associated with nighttime voiding frequency, while the PSQI global score was positively associated with it. Imidafenacin significantly improved the OABSS, PSQI, and ESS, as well as the SF-8 score. This is the first study using the SF-8 to show that nocturia and sleep disturbance have a major influence on comprehensive HRQOL and that the SF-8 can be used to monitor HRQOL in OAB patients receiving treatment for nocturia.

A prospective, comparative study of the occurrence and severity of constipation with darifenacin and trospium in overactive bladder

INTRODUCTION

Darifenacin and trospium are the commonly used antimuscarinics in the management of overactive bladder (OAB). Constipation is the second most common treatment related side-effect. Though its incidence with the above two medications is known, data on their comparative severity and impact on patient's well-being is lacking.

MATERIALS AND METHODS

Sixty subjects with OAB included in the study were randomized in 1:1 fashion to receive either darifenacin 7.5 mg OD or trospium extended release 60 mg OD. Treatment response was monitored using overactive bladder symptom score (OABSS). The severity of constipation was assessed using McMillan & Williams Constipation assessment scale (CAS), Bristol stool form scale and Knowles-Eccersley-Scott-Symptom (KESS) questionnaire score administered at baseline, 2 and 4 weeks of treatment.

RESULTS

OABSS improved significantly, -5.80 ± 3.99 (p = 0.0005) and -5.27 ± 2.98 (p = 0.0005) in darifenacin and trospium groups respectively. However, the difference between the two groups was not significant either at 2 weeks (p = 0.952) or 4 weeks (p = 0.654) of treatment. A significant decrease in stool consistency was noted with darifenacin treatment (p < 0.05), but the same was not seen with trospium (p = 0.076). There was no significant difference in scores of KESS questionnaire between baseline, 2 weeks and 4 weeks, both within the group and between the groups (p > 0.05). McMillan & Williams CAS scores increased at week 2 and week 4, in comparison with baseline scores in both darifenacin and trospium treated patients, however, the difference between the two groups was not statistically significant (p > 0.05).

CONCLUSION

Darifenacin and trospium are equally efficacious and comparable in tolerability in terms of constipation severity and its impact on patient well-being.

A randomised, prospective double-blind, propiverine-controlled trial of imidafenacin in patients with overactive bladder

AIM

To assess the efficacy and safety of imidafenacin compared with propiverine for treatment of overactive bladder (OAB) in Korean patients.

MATERIALS AND METHODS

Patients with OAB symptoms were randomised to double-blind treatment with 0.1 mg of imidafenacin twice daily (group A) or propiverine 20 mg once daily (group B) for 12-week regimen, and assessed for efficacy and safety. The primary efficacy outcome was per cent change of weekly urgency urinary incontinence (UUI) episodes at week 12. The secondary efficacy outcomes were changes in the micturitions per day, urine volume voided per micturition, urgency episodes per day, complete disappearance of incontinence episodes and severity of urgency from baseline to week 12. Quality of life and safety profiles were also compared.

RESULTS

Of 162 patients randomised, 140 completed the study protocol. The per cent change of weekly UUI episodes at week 12 was -69.1% in group A and -70.4% in group B (both p < 0.0001). The lower limit of 95% one-sided confidence interval of the difference between the groups was above the non-inferiority margin (-19.42%). Other voiding parameters and quality of life significantly improved at week 12 in both the groups. The discontinuation rates caused by adverse events were low in both the groups. While dry mouth was the most common adverse event (group A: 28.4% vs. B: 30.4%, p = 0.783), the severity of dry mouth was significantly less in the group A than B (p = 0.042) There were no significant differences in other safety profiles.

CONCLUSIONS

After the 12-week treatment of imidafenacin 0.1 mg twice daily, all OAB symptoms and quality of life improved. Imidafenacin was not inferior to propiverine for the reduction of UUI episodes, and was better tolerated than propiverine in the safety profile. Our results indicate that imidafenacin is a safe and effective drug in Korean patients with OAB.