Urovant Sciences issued positive top-line results from the phase III EMPOWUR trial evaluating vibegron in adults with symptoms of overactive bladder. EMPOWUR was an international randomized, double-blind placebo- and active comparator controlled clinical trial evaluating the safety and efficacy of investigational vibegron in men and women with symptoms of overactive bladder, including frequent urination, sudden urge to urinate, and urge incontinence or leakage. A total of 1,518 patients were randomized across 215 study sites into one of three groups for a 12-week treatment period with a four-week safety follow-up period: vibegron 75 mg administered orally once daily; placebo administered orally once daily; or tolterodine ER 4 mg administered orally once daily. In the primary efficacy analysis, once-daily vibegron met the co-primary endpoints at week 12, achieving statistical significance over placebo on both reduction in daily urge urinary incontinence (UUI) episodes and reduction in daily micturitions. The difference from placebo was statistically significant as early as week 2, which was the first timepoint measured, for both UUI episodes and micturitions, and statistically significant efficacy was maintained at all timepoints measured through the end of the study for both endpoints. Vibegron also achieved numerically better efficacy than tolterodine at all timepoints measured. Tolterodine was the active control in this study and is current prescribed standard of care for OAB treatment. Vibegron was well tolerated and the most common adverse events were headache, nasopharyngitis, diarrhea and nausea. Based on these results Urovant intends to file a New Drug Application (NDA) with the U.S. FDA by early 2020. source
About Overactive Bladder
Overactive bladder causes a sudden urge to urinate. The urge may be difficult to stop, and overactive bladder may lead to the involuntary loss of urine (urge incontinence). Overactive bladder occurs because the muscles of the bladder start to contract involuntarily even when the volume of urine in your bladder is low. This involuntary contraction creates the urgent need to urinate.
Vibegron is an oral, once-daily, small molecule beta-3 agonist. The beta-3 adrenergic receptor is the most prevalent beta-adrenergic receptor subtype on the smooth muscle around the bladder. Bladder filling involves the relaxation of this muscle and the contraction of the urethral smooth muscle, while voiding involves contracting the bladder muscle and relaxation of the urethral muscle. Studies of isolated human bladder smooth muscle have shown that selective activation of the beta-3 adrenergic receptor results in smooth muscle relaxation. Therefore, beta-3 stimulation can increase bladder capacity and reduce the symptoms of OAB.