A Randomized, Double-Blind, Placebo-Controlled, Bridging Study to Evaluate the Efficacy and Safety of Vibegron in Treating Korean Patients With Overactive Bladder

Purpose Vibegron, a novel, potent β3 agonist, has been approved for clinical use in overactive bladder (OAB) treatment in Japan and the Unites States. We performed a bridging study to investigate the efficacy and safety of a daily 50-mg vibegron (code name JLP-2002) dose in Korean patients with OAB. Methods A multicenter, randomized, double-blind, placebo-controlled study was conducted from September 2020 to August 2021. Adult patients with OAB with a symptom duration of more than 6 months entered a 2-week placebo run-in phase. Eligibility was assessed at the end of this phase and selected patients entered a double-blind treatment phase after 1:1 randomization to either the placebo or vibegron (50 mg) group. The study drug was administered once daily for 12 weeks and follow-up visits were scheduled at weeks 4, 8, and 12. The primary endpoint was the change in mean daily micturition at the end of treatment. The secondary endpoints included changes in OAB symptoms (daily micturition, nocturia, urgency, urgency incontinence, and incontinence episodes, and mean voided volume per micturition) and safety. A constrained longitudinal data model was used for statistical analysis. Results Patients who took daily vibegron had significant improvements over the placebo group in both primary and secondary endpoints, except for daily nocturia episodes. The proportions of patients with normalized micturition and resolution of urgency incontinence and incontinence episodes were significantly higher in vibegron group than in the placebo. Vibegron also improved the patients’ quality of life with higher satisfaction rates. The incidence of adverse events in the vibegron and placebo groups was similar with no serious, unexpected adverse drug reactions. No abnormality in electrocardiographs was observed as well as no significant increase in postvoid residual volume. Conclusions Once daily vibegron (50 mg) for 12 weeks was effective, safe, and well-tolerated in Korean patients with OAB

In vitro evaluation of Aloe saponaria as a potential feed additive to modulate ruminal fermentation and microbial diversity

ABSTRACTSaponin possessed antiprotozoal activity; therefore, it is generally used to mitigate enteric methane (CH4) emission in ruminant nutrition. The objective of this study was to evaluate the effects of Aloe saponaria (AS) supplementation on rumen fermentation, CH4, and microbial diversity in an in vitro experiment over 48 h incubation. Five treatments were used: (1) no additives (CON), 1% and 2% dosage of heat-dried AS (HAS), and freeze-dried AS (FAS), and the experiments were performed three times. After the incubation, volatile fatty acids (VFAs), CH4 proportion in total gas, and microbial diversity were evaluated. Gas production was assessed at 3, 6, 9, 12, 24, 36, and 48 h incubation. FAS addition significantly increased gas production compared to CON except for 6 and 48 h, whereas HAS addition did not significantly affect the gas production at all observed time points. AS addition significantly increased total VFA and the absolute abundances of fungi and Ruminococcus albus regardless of drying method. There was no significant change in the CH4 proportion at 48 h, although the reduction in ciliate protozoa was detected in FAS-treated groups. In conclusion, FAS may be an effective feed additive to improve ruminal fermentation via enhancing feed utilization by rumen microbes

Molecular Mechanisms of Neurogenic Lower Urinary Tract Dysfunction after Spinal Cord Injury

This article provides a synopsis of current progress made in fundamental studies of lower urinary tract dysfunction (LUTD) after spinal cord injury (SCI) above the sacral level. Animal models of SCI allowed us to examine the effects of SCI on the micturition control and the underlying neurophysiological processes of SCI-induced LUTD. Urine storage and elimination are the two primary functions of the LUT, which are governed by complicated regulatory mechanisms in the central and peripheral nervous systems. These neural systems control the action of two functional units in the LUT: the urinary bladder and an outlet consisting of the bladder neck, urethral sphincters, and pelvic-floor striated muscles. During the storage phase, the outlet is closed, and the bladder is inactive to maintain a low intravenous pressure and continence. In contrast, during the voiding phase, the outlet relaxes, and the bladder contracts to facilitate adequate urine flow and bladder emptying. SCI disrupts the normal reflex circuits that regulate co-ordinated bladder and urethral sphincter function, leading to involuntary and inefficient voiding. Following SCI, a spinal micturition reflex pathway develops to induce an overactive bladder condition following the initial areflexic phase. In addition, without proper bladder–urethral-sphincter coordination after SCI, the bladder is not emptied as effectively as in the normal condition. Previous studies using animal models of SCI have shown that hyperexcitability of C-fiber bladder afferent pathways is a fundamental pathophysiological mechanism, inducing neurogenic LUTD, especially detrusor overactivity during the storage phase. SCI also induces neurogenic LUTD during the voiding phase, known as detrusor sphincter dyssynergia, likely due to hyperexcitability of Aδ-fiber bladder afferent pathways rather than C-fiber afferents. The molecular mechanisms underlying SCI-induced LUTD are multifactorial; previous studies have identified significant changes in the expression of various molecules in the peripheral organs and afferent nerves projecting to the spinal cord, including growth factors, ion channels, receptors and neurotransmitters. These findings in animal models of SCI and neurogenic LUTD should increase our understanding of pathophysiological mechanisms of LUTD after SCI for the future development of novel therapies for SCI patients with LUTD

Pathophysiology of Overactive Bladder and Pharmacologic Treatments Including β3-Adrenoceptor Agonists -Basic Research Perspectives-

Overactive bladder (OAB) is a symptom-based syndrome defined by urinary urgency, frequency, and nocturia with or without urge incontinence. The causative pathology is diverse; including bladder outlet obstruction (BOO), bladder ischemia, aging, metabolic syndrome, psychological stress, affective disorder, urinary microbiome, localized and systemic inflammatory responses, etc. Several hypotheses have been suggested as mechanisms of OAB generation; among them, neurogenic, myogenic, and urothelial mechanisms are well-known hypotheses. Also, a series of local signals called autonomous myogenic contraction, micromotion, or afferent noises, which can occur during bladder filling, may be induced by the leak of acetylcholine (ACh) or urothelial release of adenosine triphosphate (ATP). They can be transmitted to the central nervous system through afferent fibers to trigger coordinated urgency-related detrusor contractions. Antimuscarinics, commonly known to induce smooth muscle relaxation by competitive blockage of muscarinic receptors in the parasympathetic postganglionic nerve, have a minimal effect on detrusor contraction within therapeutic doses. In fact, they have a predominant role in preventing signals in the afferent nerve transmission process. β3-adrenergic receptor (AR) agonists inhibit afferent signals by predominant inhibition of mechanosensitive Aδ-fibers in the normal bladder. However, in pathologic conditions such as spinal cord injury, it seems to inhibit capsaicin-sensitive C-fibers. Particularly, mirabegron, a β3-agonist, prevents ACh release in the BOO-induced detrusor overactivity model by parasympathetic prejunctional mechanisms. A recent study also revealed that vibegron may have 2 mechanisms of action: inhibition of ACh from cholinergic efferent nerves in the detrusor and afferent inhibition via urothelial β3-AR