FDA Approves New Beta-3 Agonist to Treat Overactive Bladder

By Jessica Pyhtila, PharmD, BCGP, BCPS

The FDA recently approved vibegron (Gemtesa), a beta-3 agonist for the treatment of overactive bladder in adults who have symptoms of urge urinary incontinence, urgency, and urinary frequency. Like other beta-3 agonists, vibegron works by increasing bladder capacity, causing the detrusor smooth muscle to relax during bladder filling. According to the American Urological Association 2019 guidelines, both beta-3 agonists and antimuscarinics are first-choice pharmacological treatments for overactive bladder, second only to nonpharmacological behavioral therapies.

Clinical trials leading to vibegron’s approval showed that it had a statistically significant impact on the average daily number of micturitions, average daily number of urinary urge incontinence episodes, average daily number of urgency episodes, and average volume voided per micturition.

Vibegron comes as a 75mg tablet and is intended for once daily oral administration. Importantly, no dose modifications are required for those with impaired renal function, although the drug has not been studied in end-stage renal disease and should, therefore, be avoided in those with the condition. The tablet should be swallowed whole with a glass of water but may also be crushed and mixed with applesauce if desired.

Common side effects of vibegron include headache, urinary tract infection, nasopharyngitis, diarrhea, nausea, and upper respiratory tract infection. Vibegron carries a warning for urinary retention, noting that patients with bladder outlet obstruction and those on concurrent antimuscarinic therapy are at higher risk. Vibegron should be discontinued if urinary retention occurs.

Vibegron has been found to have a drug interaction with digoxin and can increase digoxin’s maximum concentration. For this reason, digoxin levels should be monitored before, during and after any discontinuation of vibegron therapy.

References:

American Urological Association. “Diagnosis and Treatment of Non-Neurogenic Overactive Bladder (OAB) in Adults: an AUA/SUFU Guideline (2019).” 2019. Retrieved from: https://www.auanet.org/guidelines/overactive-bladder-(oab)-guideline

Food & Drug Administration. “Gemtesa.” 2020. Retrieved from: https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/213006s000lbl.pdf