Translational science approach for assessment of cardiovascular effects and proarrhythmogenic potential of the beta-3 adrenergic agonist mirabegron

Examining the safety of mirabegron: an analysis of real-world pharmacovigilance data from the US FDA adverse event reporting system (FAERS) database

Background: Mirabegron, the first β-3 adrenergic receptor agonist, received approval from the Food and Drug Administration (FDA) in 2012 for the treatment of overactive bladder (OAB). This pharmacovigilance study investigated the safety profile of mirabegron treatment using the US FDA Adverse Event Reporting System (FAERS) database. Methods: This study employed disproportionality analyses, including the reporting odds ratio (ROR) and Bayesian Confidence Propagation Neural Network (BCPNN) algorithm, to quantify signals of adverse events associated with mirabegron. Results: From the first quarter of 2012 to the third quarter of 2023, a comprehensive total of 14,356,234 adverse event (AE) reports were submitted to the FDA Adverse Event Reporting System database. Within this dataset, encompassing 18,763 reports specifically associated with mirabegron, healthcare professionals notably contributed 2,902 of these reports. A total of 80 preferred terms (PTs) of interest were identified using both the ROR and information component algorithms. The most common AEs included blood pressure increased, urinary retention, atrial fibrillation, dry mouth, and tachycardia, which were consistent with the product instructions. Unexpected significant AEs, such as arrhythmia, palpitations, dementia, transient ischemic attack, Parkinson's disease, anti-neutrophil cytoplasmic antibody positive vasculitis, lip swelling, and swollen tongue, were also identified. The study findings indicated that the majority of onset time occurred within 30 days (n = 358, 55.68%). However, AEs were still possible after 1 year of mirabegron treatment. Conclusion: This study provided valuable evidence for the real-world safety of mirabegron, helping clinical professionals enhance their understanding of mirabegron's safety in clinical practice. It also contributed valuable evidence for further safety studies on mirabegron.

Clinical pharmacology of β-3 adrenergic receptor agonists for cardiovascular diseases

INTRODUCTION

Few agonists of the third isotype of beta-adrenergic receptors, the β3-adrenoreceptor, are currently used clinically, and new agonists are under development for the treatment of overactive bladder disease. As the receptor is expressed in human cardiac and vascular tissues, it is important to understand their beneficial (or adverse) effect(s) on these targets.

AREAS COVERED

We discuss the most recent results of clinical trials testing the benefit and safety of β3-adrenoreceptor activation on cardiovascular outcomes in light of current knowledge on the receptor biology, genetic polymorphisms, and agonist pharmacology.

EXPERT OPINION

While evidence from small clinical trials is limited so far, the β3-agonist, mirabegron seems to be safe in patients at high cardiovascular risk but produces benefits on selected cardiovascular outcomes only at higher than standard doses. Activation of cardiovascular β3-adrenoreceptors deserves to be tested with more potent agonists, such as vibegron.

Oxytocin as a potential pharmacological tool to combat obesity

The neuropeptide oxytocin (OT) has emerged as an important anorexigen in the regulation of food intake and energy balance. It has been shown that the release of OT and activation of hypothalamic OT neurons coincide with food ingestion. Its effects on feeding have largely been attributed to limiting meal size through interactions in key regulatory brain regions governing the homeostatic control of food intake such as the hypothalamus and hindbrain in addition to key feeding reward areas such as the nucleus accumbens and ventral tegmental area. Furthermore, the magnitude of an anorexigenic response to OT and feeding-related activation of the brain OT circuit are modified by the composition and flavor of a diet, as well as by a social context in which a meal is consumed. OT is particularly effective in reducing consumption of carbohydrates and sweet tastants. Pharmacologic, genetic, and pair-feeding studies indicate that OT-elicited weight loss cannot be fully explained by reductions of food intake and that the overall impact of OT on energy balance is also partly a result of OT-elicited changes in lipolysis, energy expenditure, and glucose regulation. Peripheral administration of OT mimics many of its effects when it is given into the central nervous system, raising the questions of whether and to what extent circulating OT acts through peripheral OT receptors to regulate energy balance. Although OT has been found to elicit weight loss in female mice, recent studies have indicated that sex and estrous cycle may impact oxytocinergic modulation of food intake. Despite the overall promising basic research data, attempts to use OT in the clinical setting to combat obesity and overeating have generated somewhat mixed results. The focus of this mini-review is to briefly summarize the role of OT in feeding and metabolism, address gaps and inconsistencies in our knowledge, and discuss some of the limitations to the potential use of chronic OT that should help guide future research on OT as a tailor-made anti-obesity therapeutic.

The Efficacy and Safety of Mirabegron for the Treatment of Neurogenic Lower Urinary Tract Dysfunction: A Systematic Review and Meta-analysis

Background and Objective: Over the past few years, mirabegron has been increasingly used as a therapeutic option for neurogenic lower urinary tract dysfunction. Here, we carried out a meta-analysis to investigate the efficacy and safety of mirabegron for the treatment of neurogenic lower urinary tract dysfunction.

Methods: We used a range of databases to retrieve randomized controlled trials (RCTs) relating to mirabegron in patients with neurogenic lower urinary tract dysfunction: PubMed, Embase, and Cochrane Library; our strategy conformed to the PICOS (populations, interventions, comparators, outcomes, and study designs) strategy.

Results: Our analyses involved four RCTs involving 245 patients. We found that mirabegron treatment resulted in a significant improvement in bladder compliance [mean difference (MD) = 19.53, 95% confidence interval (CI): 14.19 to 24.87, P < 0.00001], urinary incontinence episodes (MD = −0.78, 95% CI: −0.89 to −0.67, P < 0.00001) and Incontinence Quality of Life (I-QOL) (MD = 8.02, 95% CI: 3.20 to 12.84, P = 0.001). Significant differences were detected in terms of Patient Perception of Bladder Condition (PPBC) (MD = −0.54, 95% CI: −1.46 to 0.39, P = 0.26) and urinary urgency episodes (MD = −0.72, 95% CI: −3.1 to 1.66, P = 0.55). With regard to safety, there were no significant differences between mirabegron and control groups in terms of the incidence of drug-related adverse events [odds ratio (OR): 0.83, 95% CI: 0.43 to 1.59, P = 0.57], arrhythmias (OR: 1.27, 95% CI: 0.37 to 4.38, P = 0.70), hypertension (OR: 0.70, 95% CI: 0.13 to 3.82, P = 0.68), or post-voiding residual volume (MD: 1.62, 95% CI: −9.00 to 12.24, P = 0.77).

Conclusion: Mirabegron is an efficacious and safe treatment for patients with neurogenic lower urinary tract dysfunction.

Mirabegron Ameliorated Atherosclerosis of ApoE-/- Mice in Chronic Intermittent Hypoxia but Not in Normoxia

PURPOSE

It has been established that obstructive sleep apnea (OSA) is an independent risk factor for atherosclerosis. Chronic intermittent hypoxia (CIH) activates sympathoadrenal system and upregulates β3 adrenergic receptor (β3 AR). However, the effect of selective β3 AR agonist mirabegron in CIH-induced atherosclerosis remains unknown.

METHODS

We generated a CIH-induced atherosclerosis model through exposing ApoE^-/- mice to CIH (8 h per day, cyclic inspiratory oxygen fraction 5-21%, 60-s cycle) for 6 weeks after 4-week high-fat dieting and investigated the effects of mirabegron, a selective β3 AR agonist, on CIH-induced atherosclerosis. The coronary endarterectomy (CE) specimens from coronary artery disease patients with OSA and without OSA were collected.

RESULTS

The expression of β3 AR was significantly elevated in CIH-induced atherosclerosis model. Furthermore, treatment with mirabegron (10mg/kg per day by oral administration for 6 weeks) ameliorated atherosclerosis in ApoE^-/- mice in CIH but not in normoxia. Mechanistically, mirabegron activated β3 AR and ameliorated intraplaque oxidative stress by suppressing p22phox expression and reactive oxygen species (ROS) level. In addition, in human CE specimens, β3 AR was also upregulated associated with increased p22phox expression and ROS level both in the lumen and in the plaque of coronary artery in OSA subjects.

CONCLUSION

This study first demonstrated that mirabegron impeded the progression of CIH-induced atherosclerosis, at least in part, via β3 AR-mediated oxidative stress, suggesting a promising therapeutic strategy for protecting against atherosclerosis induced by CIH.

The effect of mirabegron on energy expenditure and brown adipose tissue in healthy lean South Asian and Europid men

AIM

To compare the effects of cold exposure and the β3-adrenergic receptor agonist mirabegron on plasma lipids, energy expenditure and brown adipose tissue (BAT) activity in South Asians versus Europids.

MATERIALS AND METHODS

Ten lean Dutch South Asian (aged 18-30 years; body mass index [BMI] 18-25 kg/m² ) and 10 age- and BMI-matched Europid men participated in a randomized, double-blinded, cross-over study consisting of three interventions: short-term (~ 2 hours) cold exposure, mirabegron (200 mg one dose p.o.) and placebo. Before and after each intervention, we performed lipidomic analysis in serum, assessed resting energy expenditure (REE) and skin temperature, and measured BAT fat fraction by magnetic resonance imaging.

RESULTS

In both ethnicities, cold exposure increased the levels of several serum lipid species, whereas mirabegron only increased free fatty acids. Cold exposure increased lipid oxidation in both ethnicities, while mirabegron increased lipid oxidation in Europids only. Cold exposure and mirabegron enhanced supraclavicular skin temperature in both ethnicities. Cold exposure decreased BAT fat fraction in both ethnicities. After the combination of data from both ethnicities, mirabegron decreased BAT fat fraction compared with placebo.

CONCLUSIONS

In South Asians and Europids, cold exposure and mirabegron induced beneficial metabolic effects. When combining both ethnicities, cold exposure and mirabegron increased REE and lipid oxidation, coinciding with a higher supraclavicular skin temperature and lower BAT fat fraction.

The use of mirabegron in neurogenic bladder: a systematic review

PURPOSE

To evaluate the use of mirabegron in patients with neurogenic bladder.

METHODS

A systematic review of the literature was conducted using four databases (Medline via PubMed, Scopus, Cochrane, and EMBASE). Articles evaluating mirabegron in neurogenic bladder patients were collected, and assessment of the drug's efficacy was reviewed according to clinical and urodynamic parameters.

RESULTS

Seven studies were selected and a total of 302 patients with NB were evaluated, ranging from 15 to 66 patients per study. All of the patients had received antimuscarinics as a previous treatment modality. Mirabegron was used as a second-line treatment after antimuscarinics lacked efficacy or caused adverse effects. The duration of the treatments ranged from 4 to 12 weeks. Reported in two studies each, bladder compliance and maximal cystometric capacity were the most commonly improved urodynamic parameters. In the majority of the studies, positive outcomes were reported for clinical scores. Additionally, analysis of the IPSS subscores revealed an improvement of storage symptoms as opposed to voiding symptoms. In all of the studies, mirabegron was well tolerated.

CONCLUSION

Mirabegron appears to be an effective treatment in the management of neurogenic bladder unresponsive to antimuscarinics, particularly in patients presenting with storage symptoms. There is still no evidence concerning the use of mirabegron as a first-line therapy for neurogenic bladder.

[Contribution of pharmacological research to the discovery of a first-in-class drug, mirabegron, for the treatment of overactive bladder]

Overactive bladder (OAB) is defined as urgency, with or without urge incontinence, usually with frequency and nocturia. Antimuscarinic drugs are often prescribed as a standard care; however, the treatment discontinuation due to the adverse events including dry mouth and constipation has been an issue. Taking these situations into account, we considered that a novel OAB drug having a different mechanism from antimuscarinics fills the unmet medical need. It has been known that, during bladder filling, activation of sympathetic nerves results in bladder smooth muscle relaxation via the β-adrenergic receptor (AR) stimulation. In 1999, three Japanese groups independently provided evidence for the existence of β₃-AR in human bladder smooth muscles and some of these groups showed that β₃-AR activation is mainly involved in the relaxation induced by β adrenergic stimulation. Therefore, we conducted pharmacological research focusing on β₃-AR as a novel target molecule for the treatment of OAB. A selective β₃-AR agonist mirabegron showed the relaxant effect in rat bladder smooth muscle and decreased resting intravesical pressure in anesthetized rats. Mirabegron also improved storage function in a rat detrusor overactivity model. Furthermore, in vitro isometric contraction study using human bladder tissues was conducted to predict the clinical efficacy and mirabegron showed the relaxant effect in human bladder smooth muscle. In clinical studies with OAB patients, mirabegron demonstrated promising efficacy and tolerability. These pharmacological evidences contributed to the approval of mirabegron as a first-in-class drug for OAB treatment in Japan ahead of other countries.

Mirabegron, a Clinically Approved β3 Adrenergic Receptor Agonist, Does Not Reduce Infarct Size in a Swine Model of Reperfused Myocardial Infarction

The administration of the selective β3 adrenergic receptor (β3AR) agonist BRL-37344 protects from myocardial ischemia/reperfusion injury (IRI), although the lack of clinical approval limits its translatability. We tested the cardioprotective effect of mirabegron, the first-in-class β3AR agonist approved for human use. A dose-response study was conducted in 6 pigs to select the highest intravenous dose of mirabegron without significant detrimental hemodynamic effect. Subsequently, closed chest anterior myocardial infarction (45 min ischemia followed by reperfusion) was performed in 26 pigs which randomly received either mirabegron (10 μg/kg) or placebo 5 min before reperfusion. Day-7 cardiac magnetic resonance (CMR) showed no differences in infarct size (35.0 ± 2.0% of left ventricle (LV) vs. 35.9 ± 2.4% in mirabegron and placebo respectively, p = 0.782) or LV ejection fraction (36.3 ± 1.1 vs. 34.6 ± 1.9%, p = 0.430). Consistent results were obtained on day-45 CMR. In conclusion, the intravenous administration of the clinically available selective β3AR agonist mirabegron does not reduce infarct size in a swine model of IRI.

Cardiovascular Safety of the β3 -Adrenoceptor Agonist Mirabegron and the Antimuscarinic Agent Solifenacin in the SYNERGY Trial

There have been concerns that treatment of overactive bladder with β₃ -adrenoceptor agonists may potentially have detrimental cardiovascular (CV) side effects. We evaluated the CV safety of mirabegron, a β₃ -adrenoceptor agonist, alone and in combination therapy with the antimuscarinic agent solifenacin. The SYNERGY trial was a multinational, multicenter, randomized, double-blind, parallel-group, placebo and active-controlled phase 3 trial. Patients were randomized to receive solifenacin 5 mg + mirabegron 50 mg (combination 5 + 50 mg), solifenacin 5 mg + mirabegron 25 mg (combination 5 + 25 mg), solifenacin 5 mg monotherapy, mirabegron 25 mg monotherapy, mirabegron 50 mg monotherapy, or placebo for a 12-week double-blind treatment period. A total of 3398 patients were included in the study. Mean changes from baseline to the end of therapy in ECG parameters were similar across treatment groups, although there was an increase in heart rate of 1 beat/minute in the mirabegron treatment groups. There were no clinically meaningful differences in change from baseline in QTcF between monotherapies and placebo and between monotherapies and combination therapy. There were very few major CV events: 1 of 853 (0.1%) with a nonfatal myocardial infarction in the combination 5 + 25 mg group, 2 of 848 (0.2%) with a nonfatal stroke in the combination 5 + 50 mg group, and no events in the other groups. This CV safety analysis of the combination of mirabegron and solifenacin showed rates of CV events comparable with those for monotherapy treatments based on assessments of vital signs, electrocardiograms, and adjudicated CV events.

Cardiovascular effects of antimuscarinic agents and beta3-adrenergic receptor agonist for the treatment of overactive bladder

INTRODUCTION

Overactive bladder (OAB) syndrome is common in the general population, particularly in elderly patients. Antimuscarinic drugs (AMs) are considered the mainstay pharmaceutical treatment of OAB whereas β3-adrenoceptor agonists, such as mirabegron, represent a good alternative. Owing to the important role of muscarinic and β3 receptors in cardiovascular (CV) tissue and to the fact that OAB patients often have CV comorbidities, the safety-profile of these drugs constitute an important challenge.

AREAS COVERED

The aim of this review is to evaluate the CV effects of AMs and mirabegron in OAB. A systematic literature search from inception until December 2017 was performed on PubMed and Medline.

EXPERT OPINION

AMs are generally considered to have good CV safety profile but, however, they may cause undesirable adverse events, such as dry mouth, constipation. CV AEs are rare but noteworthy, the most common CV consequences related to the use of these drugs are constituted by an increase in HR and QT interval. Mirabegron has similar efficacy and tolerability to AMs but causes less adverse events, with either modest hypertension and modest increase in HR (<5 bpm) being the most commonly reported.

Safety pharmacology methods and models in an evolving regulatory environment

This editorial prefaces the annual themed issue on safety pharmacology (SP) methods published in the Journal of Pharmacological and Toxicological Methods (JPTM). We highlight here the content derived from the recent 2016 Safety Pharmacology Society (SPS), Canadian Society of Pharmacology and Therapeutics (CSPT), and Japanese Safety Pharmacology Society (JSPS) joint meeting held in Vancouver, B.C., Canada. This issue of JPTM continues the tradition of providing a publication summary of articles primarily presented at the joint meeting with direct bearing on the discipline of SP. As the regulatory landscape is expected to evolve with revision announced for the existing guidance document on non-clinical proarrhythmia risk assessment (ICHS7B) there is also imminent inception of the Comprehensive in vitro Proarrhythmia Assay (CiPA) initiative. Thus, the field of SP is dynamically progressing with characterization and implementation of numerous alternative non-clinical safety models. Novel method development and refinement in all areas of the discipline are reflected in the content.