What is the recommended treatment and dosage of Vibegron (beta-3 adrenergic agonist) for overactive bladder?

Vibegron Treatment for Overactive Bladder

The recommended dose of vibegron for overactive bladder is 75 mg orally once daily, which can be used as monotherapy or combined with an antimuscarinic agent if response is inadequate. 1

Indications

Vibegron is FDA-approved for treating overactive bladder with symptoms of urge urinary incontinence, urgency, and urinary frequency in adults, including adult males on pharmacological therapy for benign prostatic hyperplasia. 1

Treatment Algorithm

First-Line Approach

• Begin with behavioral interventions including bladder training, pelvic floor exercises, and fluid management before initiating pharmacological therapy. 2

Pharmacological Treatment

• For patients who fail first-line behavioral therapy, initiate vibegron 75 mg once daily. 2, 1
• The tablet should be swallowed whole with water, though it may be crushed and mixed with applesauce if needed. 1
• No dose adjustment is required based on age, including elderly patients ≥65 and ≥75 years. 3

Combination Therapy

• If monotherapy provides inadequate response, add an antimuscarinic agent (such as solifenacin 5 mg once daily) to vibegron. 2
• This combination approach is supported by clinical evidence showing superior efficacy compared to monotherapy alone. 2

Efficacy Profile

• Vibegron demonstrates rapid onset of action, with significant improvements in all OAB symptoms beginning at week 2 and sustained through 52 weeks of treatment. 4, 5
• At 12 weeks, vibegron reduces micturitions by 1.8 episodes per day versus 1.3 for placebo (p<0.001). 4
• Among incontinent patients, urge incontinence episodes decrease by 2.0 episodes per day versus 1.4 for placebo (p<0.0001). 4
• In patients aged ≥65 years, 50.0% achieved ≥75% reduction in urge incontinence episodes versus 29.8% with placebo (p<0.0001). 3

Advantages Over Antimuscarinics

• Vibegron offers significantly lower risk of anticholinergic side effects compared to antimuscarinics, making it particularly advantageous for elderly patients. 2
• The incidence of dry mouth with vibegron (1.8%) is substantially lower than tolterodine (5.2%). 5
• Unlike antimuscarinics, vibegron does not carry risks of constipation, cognitive impairment, or increased dementia risk. 6
• Vibegron has fewer drug interactions compared to mirabegron, another β3-adrenoceptor agonist. 2

Safety Monitoring

Contraindications

• Do not use vibegron in patients with prior hypersensitivity reactions to vibegron or any product components. 1

Key Warnings

• Monitor for urinary retention, especially in patients with bladder outlet obstruction or those taking concurrent antimuscarinic medications. 1
• Discontinue vibegron if urinary retention develops. 1
• Angioedema of the face and/or larynx has been reported; discontinue immediately if this occurs. 1

Drug Interactions

• Measure serum digoxin concentrations before initiating vibegron and monitor levels to titrate digoxin dose appropriately. 1

Cardiovascular Safety

• Vibegron is not associated with clinically meaningful effects on blood pressure or heart rate. 6
• The incidence of hypertension with vibegron (1.7%) is identical to placebo (1.7%) and lower than tolterodine (2.9-3.3%). 4, 3

Special Populations

Elderly Patients

• Vibegron demonstrates robust efficacy in patients ≥65 and ≥75 years with no dose adjustment required. 3
• The safety profile in elderly patients is favorable, with cardiovascular adverse events occurring in <2% of patients, similar to placebo. 3

Renal Impairment

• Vibegron is not recommended in end-stage renal disease with or without hemodialysis. 1

Hepatic Impairment

• Vibegron is not recommended in severe hepatic impairment. 1

Common Adverse Events

The most common adverse reactions (≥2%) include headache, urinary tract infection, nasopharyngitis, diarrhea, nausea, and upper respiratory tract infection. 1 Treatment discontinuation due to adverse events is low (1.7% for vibegron versus 1.1% for placebo). 4

Clinical Pitfalls to Avoid

• Do not withhold vibegron from elderly patients due to age concerns—the drug is safe and effective in this population without dose adjustment. 3
• Do not assume all β3-agonists have identical drug interaction profiles—vibegron has fewer interactions than mirabegron. 2
• Remember to assess for bladder outlet obstruction before initiating therapy, as urinary retention risk increases in this population. 1
• Regular reassessment of symptom improvement and adverse effects is necessary throughout treatment. 2