Urovant Sciences announced that it enrolled its first patient in a Phase 2a clinical trial evaluating vibegron in patients with abdominal pain due to irritable bowel syndrome (IBS) on December 31, 2018. The company’s investigational new drug application was recently accepted by the U.S. Food and Drug Administration. There are no currently marketed drugs indicated specifically for IBS-associated pain. The Phase 2a trial is a double-blind, placebo-controlled study in women with abdominal pain due to IBS with predominant diarrhea (IBS-D) or mixed episodes of diarrhea and constipation (IBS-M). The study is expected to enroll approximately 200 patients in the United States, randomized to receive either 75 mg of vibegron or placebo, administered orally once daily for a 12-week period. The primary endpoint is the proportion of patients who achieve at least a 30% improvement in the average worst abdominal pain score at week 12. Other clinical endpoints include Global Improvement Scale ratings, stool symptoms and safety. Vibegron is an investigational oral beta-3 adrenergic receptor agonist currently being assessed for the treatment of overactive bladder. Urovant recently announced the completion of enrollment in its international Phase 3 clinical trial evaluating the safety and efficacy of vibegron as treatment for adults with symptoms of overactive bladder. Data available to date indicate vibegron is well tolerated. Vibegron has not been approved for commercialization by the U.S. Food and Drug Administration.