Cardiovascular Risk in Users of Mirabegron Compared with Users of Antimuscarinic Treatments for Overactive Bladder: Findings from a Non-Interventional, Multinational, Cohort Study

Discovery of Diphenyl Ether Derivatives as Novel BKCa Channel Activators: Structure-Activity Relationship, Cryo-EM Complex Structures, and In Vivo Animal Studies

The BKCa channel, a large-conductance calcium-activated potassium channel, plays a crucial role in maintaining the homeostasis of the micturition cycle and airway-related functions. In this study, we optimized a novel BKCa channel activator, 4d, with a diphenyl ether structure identified from library screening. This led to the discovery of potent activators, 10b (EC50 = 0.12 μM, cell-based assay) and 51b, an orally bioavailable derivative. Compound 10b demonstrated potent in vivo efficacy in a spontaneous hypertensive rat (SHR) of urinary incontinence model, while compound 51b showed dose-dependent cough suppression efficacy with an ED50 of 11.8 mg/kg in a citric acid-induced cough model. Furthermore, we reported the cryo-electron microscopy (cryo-EM) structures of the BKCa channel in complex with 10b and 51b at resolutions of 2.8 and 3.4 Å. Based on structural analyses, we determined the binding sites and key interaction residues of 51b, which were validated via mutation studies.

Lessons learned from a multi-data source research collaboration: The mirabegron post-authorization safety study program

BACKGROUND

Many factors contribute to developing and conducting a successful multi-data source, non-interventional, post-authorization safety study (NI-PASS) for submission to multiple health authorities. Such studies are often large undertakings; evaluating and sharing lessons learned can provide useful insights to others considering similar studies.

OBJECTIVES

We discuss challenges and key methodological and organizational factors that led to the delivery of a successful post-marketing requirement (PMR)/PASS program investigating the risk of cardiovascular and cancer events among users of mirabegron, an oral medication for the treatment of overactive bladder.

RESULTS

We provide context and share learnings, including sections on research program collaboration, scientific transparency, organizational approach, mitigation of uncertainty around potential delays, validity of study outcomes, selection of data sources and optimizing patient numbers, choice of comparator groups and enhancing precision of estimates of associations, potential confounding and generalizability of study findings, and interpretation of results.

CONCLUSIONS

This large PMR/PASS program was a long-term commitment from all parties and benefited from an effective coordinating center and extensive scientific interactions across research partners, scientific advisory board, study sponsor, and health authorities, and delivered useful learnings related to the design and organization of multi-data source NI-PASS.

Obesity - Standards, trends and advances

Obesity continues to be a significant global health concern, giving rise to various complications. This review article explores the current standards and emerging innovations in diagnosing and treating obesity, including recent disease name change, staging system or therapeutic goals. This narrative review has been based on recent scientific articles from PubMed database, limiting the scope of topics to current standards and upcoming developments and breakthroughs in the diagnosis and treatment of obesity. The educational and informative nature of the review has been maintained in order to make the information presented accessible to both researchers and clinical practitioners. The recognition of diverse obesity phenotypes has prompted a paradigm shift towards a complex and patient-centered approach to diagnosis and therapy. Pharmacotherapy for obesity is evolving rapidly, with ongoing research focusing on novel molecular targets and metabolic pathways. Promising developments include dual or triple incretin analogs, oral incretin drugs, neurotransmitter-based therapies, muscle mass-increasing treatments, and therapies targeting visceral adipose tissue browning. Despite current evidence-based international standards, the field of obesity diagnosis and treatment continues to expand, with new diagnostic tools and pharmacotherapies potentially replacing current practices. Therapeutic management should be tailored to individual patients, considering obesity phenotype, health status, lifestyle, and preferences. Looking ahead, the future holds promising opportunities for obesity management, but further research is required to assess the efficacy and safety of emerging therapies. A multifactorial and personalized approach will be pivotal in addressing the diverse challenges posed by obesity.

Therapeutic Potential for Beta-3 Adrenoreceptor Agonists in Peripheral Arterial Disease and Diabetic Foot Ulcers

Annually, peripheral arterial disease is estimated to cost over USD 21 billion and diabetic foot disease an estimated at USD 9-13 billion. Mirabegron is a TGA-approved beta-3 adrenoreceptor agonist, shown to be safe and effective in the treatment of overactive bladder syndrome by stimulating bladder smooth muscle relaxation. In this review, we discuss the potential use of beta-3 adrenoreceptor agonists as therapeutic agents repurposed for peripheral arterial disease and diabetic foot ulcers. The development of both conditions is underpinned by the upregulation of oxidative stress pathways and consequential inflammation and hypoxia. In oxidative stress, there is an imbalance of reactive oxygen species and nitric oxide. Endothelial nitric oxide synthase becomes uncoupled in disease states, producing superoxide and worsening oxidative stress. Agonist stimulation of the beta-3 adrenoreceptor recouples and activates endothelial nitric oxide synthase, increasing the production of nitric oxide. This reduces circulating reactive oxygen species, thus decreasing redox modification and dysregulation of cellular proteins, causing downstream smooth muscle relaxation, improved endothelial function and increased angiogenesis. These mechanisms lead to endothelial repair in peripheral arterial disease and an enhanced perfusion in hypoxic tissue, which will likely improve the healing of chronic ulcers.

Patient and Clinician Challenges with Anticholinergic Step Therapy in the Treatment of Overactive Bladder: A Narrative Review

Anticholinergics have been used in the treatment of overactive bladder (OAB), but their use is limited by poor tolerability and anticholinergic-related side effects. Increasingly, providers are discontinuing anticholinergic prescribing because of growing evidence of the association of anticholinergic use with increased risk of cognitive decline and other adverse effects. Newer medications for OAB, the β3-adrenergic receptor agonists mirabegron and vibegron, do not have anticholinergic properties and are typically well tolerated; however, many insurance plans have limited patient access to these newer OAB medications by requiring step therapy, meaning less expensive anticholinergic medications must be trialed and/or failed before a β3-agonist will be covered and dispensed. Thus, many patients are unable to easily access these medications. Step therapy and other drug utilization strategies (e.g., prior authorization) are often used to manage the growing costs of pharmaceuticals, but these policies do not always follow treatment guidelines and may harm patients as a result of treatment delays, discontinuations, or related increases in adverse events. Medical professionals have called for reform of drug utilization strategies through partnerships that include clinicians and policymakers. This narrative review discusses prescribing patterns for OAB treatment and the effect of switching between drugs, as well as the costs of step therapy and prior authorization on patients and prescribers.

The Differential Risk of Mortality Among Users of Overactive Bladder Anticholinergic Medications and β3 Agonists

Anticholinergic overactive bladder (OAB) medications have been studied in large observational studies to determine if they are associated with a greater risk of mortality (potentially because of their effects on the heart or the brain). Studies in different populations of old adults have shown that oxybutynin is associated with a significantly higher risk of mortality of 26-58% in comparison to other OAB anticholinergic medications or β3 agonists. In general, anticholinergic OAB medications may increase the risk of mortality, and a single multicountry study showed that β3 agonist users had a 20% lower risk of mortality compared to OAB anticholinergic users. PATIENT SUMMARY: Older adults who started using a traditional type of medication for overactive bladder (oxybutynin) had a higher risk of dying compared to people who used newer types of anticholinergic medications and to people who used overactive bladder medications that work in a different way.

Impact of Mirabegron Administration on the Blood Pressure and Pulse Rate in Patients with Overactive Bladder

Background and Objectives: To determine changes in the blood pressure (BP) and pulse rate (PR) before and after the administration of mirabegron in real-world clinical practice for patients with overactive bladder (OAB). Materials and Methods: This study was conducted in patients newly diagnosed with OAB. Before and 12 weeks after mirabegron treatment, we evaluated the effects on BP and PR. An overall examination was conducted, and the patients were divided into two groups according to their age: a young group (<65 years old) and an old group (≥65 years old). Results: A total of 263 patients were enrolled in this study. In the overall and intragroup comparisons, the systolic BP (SBP) did not change significantly after mirabegron administration. However, an increase in SBP of ≥10 mmHg was observed in 53 (20.2%), 4 (7.4%), and 49 (23.4%) in the entire group, young group, and old group, respectively (p = 0.009). Regarding diastolic BP, a significant decrease after the treatment was detected in entire (71.2 ± 11.4 versus 69.8 ± 10.7 mmHg; p = 0.041) and old patients (71.5 ± 10.6 versus 69.5 ± 10.2 mmHg; p = 0.012). There was no significant change in PR in our study population. Further examination using a propensity match score revealed that age was the risk factor for the increase in SBP after mirabegron administration. Conclusions: Mirabegron does not have any adverse effects on BP and PR. However, since some patients in this study had elevated SBP after administration, we suggest regular BP monitoring during mirabegron treatment.