Is once-daily vibegron 75mg an effective treatment for overactive bladder in the long-term?

This study looked at the long-term safety and effectiveness of 75mg vibegron (Gemtesa) for the treatment of overactive bladder (OAB). The authors found that vibegron demonstrated favorable long-term safety, tolerability, and effectiveness in patients with OAB. 

OAB involves urinary symptoms such as a sudden, uncontrolled need to urinate. OAB affects many adults worldwide. OAB can have a negative effect on the quality of life, decrease productivity, and can have serious psychological effects on people. Drugs that block acetylcholine (chemical messenger responsible for many functions in the body) have been the mainstay of treatment. They can have many side effects such as dry mouth and constipation. Many people stop using these drugs due to these side effects. 

Vibegron is a drug that stimulates certain proteins on cells that lead to the relaxation of the bladder muscle. This increases the capacity of the bladder and reduces urination urgency. Previous short-term studies have shown that vibegron-treated patients had improvements in OAB symptoms compared to patients who took a placebo. However, the safety and effectiveness of vibegron compared to acetylcholine blockers such as tolterodine (Detrol) in the long-term remain under investigation. 

There were 506 patients with OAB in this study. Patients were randomly assigned to receive once-daily vibegron 75mg or tolterodine 4mg for 52 weeks. 85% of patients completed the study.

Patients experienced significantly higher improvements in OAB symptoms over the 52-weeks of treatment with vibegron compared to tolterodine. 71.1% of the vibegron group had a 50% reduction in incontinence (urine leakage) symptoms compared to 61.9% of the tolterodine group. 61% of the vibegron group had a 75% reduction in total urgency and incontinence episodes compared to 54.4% of the tolterodine group 40.8% of the vibegron had a 100% reduction in symptoms versus 34.2% of the tolterodine group. 

Fewer patients in the vibegron group stopped treatment due to side effects (1.5%) compared to the tolterodine group (3.4%). The most common side effects seen with both drugs were high blood pressure, headache, and urinary tract infections (UTI). High blood pressure seen in 8.8% of patients taking vibegron and 8.6% of patients taking tolterodine. Urinary tract infection was seen in 6.6% of patients taking vibegron and 7.3% of patients taking tolterodine. 

The authors found that vibegron 75 mg once daily had good long-term safety and effectiveness in patients with OAB. 

This study was funded by Urovant Sciences, the manufacturer of vibegron. Vibegron was approved by the FDA for the treatment of adults with OAB symptoms.