Related Experiment Video
Updated: May 10, 2026
Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Mirabegron: β3-adrenergic receptor agonist for the treatment of overactive bladder
Mary Barna Bridgeman1, Nicholas J Friia, Christina Taft
1Ernest Mario School of Pharmacy at Rutgers, The State University of New Jersey, Piscataway, NJ, USA. mary.bridgeman@pharmacy.rutgers.edu
Objective:
To review the place in therapy of mirabegron, a new oral β3-adrenergic receptor agonist, for the treatment of overactive bladder (OAB).
Data Sources:
A literature search of MEDLINE and MEDLINE In-Process & Other Non-Indexed Citations Databases (1996-April 2013) was conducted using the key words mirabegron, receptor, adrenergic, beta-3; adrenergic beta-3 receptor; beta-3 receptor, and overactive bladder; urinary bladder; overactive. All published articles regarding mirabegron were included. References of selected articles, data from poster presentations, and abstract publications were additionally reviewed.
Study Selection And Data Extraction:
Available English-language data from reviews, abstracts, presentations, and clinical trials of mirabegron in humans were reviewed; relevant clinical data were selected and included.
Data Synthesis:
Mirabegron is the newest option for treatment of OAB with symptoms of urge incontinence. As a β3-receptor agonist, it reduces bladder muscle contractions. In two 12-week, randomized, double-blind, placebo-controlled Phase 3 studies, mirabegron significantly reduced the number of incontinence episodes per 24 hours from baseline (-1.47, -1.63, and -1.13; p < 0.05; and -1.57, -1.46, and -1.17; p < 0.05; all values for mirabegron 50 mg, 100 mg, and placebo). Micturitions per 24 hours were also reduced from baseline (-1.66, -1.75, and -1.05; p < 0.05; and -1.93, -1.77, and -1.34; p < 0.05; all values for mirabegron 50 mg, 100 mg, and placebo). A 12-month trial found mirabegron to have a safety and efficacy profile similar to that of tolterodine.
Conclusions:
Treatment of OAB initially includes lifestyle and nonpharmacologic intervention; for patients with persistent symptoms despite these treatments, drug therapy represents a next-step approach for symptom control. Mirabegron alleviates symptoms of OAB while having a mechanism of action that provides an alternative for patients who are intolerant of or who have contraindications to anticholinergic agents. The place in therapy of mirabegron relative to anticholinergics in the treatment of urge incontinence has not yet been established.
Related Concept Videos
01:17Drugs for Treatment of Diarrhea-Predominant IBS
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...
01:22Adrenergic Antagonists: Pharmacological Actions of ɑ-Receptor Blockers
α1-blockers: These drugs inhibit α1-adrenoceptors on smooth muscle cells, resulting in vasodilation. This vasodilation lowers blood pressure, making α1-blockers valuable in treating hypertension. Additionally, α1-blockers effectively address urinary obstruction...
01:26The Micturition Reflex
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating urine...
01:23Urinary Bladder
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...
01:18Adrenergic Agonists: Therapeutic Classification
Vasopressor or pressor agents: They increase blood pressure and function as cardiac stimulants. Examples include endogenous catecholamines (norepinephrine and dopamine) and synthetic agents (phenylephrine).
Bronchodilators: β2-agonists can relax bronchial muscles and widen airways. They are commonly used for treating obstructive pulmonary...
01:26Cholinergic Antagonists: Therapeutic Uses
Respiratory Tract: Ipratropium, aclidinium, and tiotropium treat asthma, chronic bronchitis, and chronic obstructive pulmonary disease (COPD). They protect against bronchoconstriction caused by irritants like cigarette smoke, sulfur dioxide, and ozone. They also help reduce nasopharyngeal secretions in common...