Urovant starts pursuit of Astellas’ overactive bladder drug Myrbetriq with new phase 3 trial

A little later than expected, Roivant group company Urovant has started its confirmatory phase 3 program for overactive bladder (OAB) drug vibegron, originally licensed from Merck & Co.



The pivotal trial—which was originally expected to get underway last year—will involve around 1,400 adults with symptoms of OAB such as urge urinary incontinence, urgency, and urinary frequency, according to Urovant.



The drug already has positive phase 2b and phase 3 data in hand, so if the latest trial is positive Urovant should be able to move ahead with regulatory filings. If approved, it could become a direct competitor to Astellas’ Myrbetriq (mirabegron), the first beta3-adrenergic agonist to reach the market for OAB. And that could present a big commercial opportunity: Astellas reported sales of its drug rose 30% to 93.1 billion yen ($876 million) in the nine months to end-January 2018 with take-up driven by greater tolerability than the widely used antimuscarinic OAB drug class.



The new study will compare oral beta3-adrenergic agonist vibegron to placebo as well as antimuscarinic mainstay tolterodine over 12 weeks. The two main outcome measures will be the change from enrollment in the average number of urinations over 24 hours, and the change in the number of urge urinary incontinence episodes in patients experiencing at least one episode per day.



Secondary endpoints will include changes in the frequency of incontinence episodes and urinary urgency episodes, as well as self-reported quality of life scores.



The biotech’s recently appointed CEO Keith Katkin—previously head of Avanir Pharma—praised the efforts of the Urovant team in preparing the trial within a year of the company’s formation.



“Overactive bladder affects millions of individuals and patients need better alternatives to the current standard of care,” he said.



Like mirabegron, vibegron works by stimulating a pathway that results in the relaxation of the bladder detrusor muscle, which in turn allows the bladder to store urine more efficiently.



Urovant was set up by Roivant last June to focus on urological disorders with vibegron as its only clinical drug candidate. It follows the standard Roivant model of picking up rights to promising drugs that are at risk of being shelved due to shifting priorities and licensed has global rights to vibegron (formerly known as MK-4618) outside Japan and certain other territories in Asia. In the latter markets, Kyorin is developing the drug under a license deal with Merck signed in 2014.



Roivant and its founder Vivek Ramaswamy could do with some good clinical trial news after a tricky few months punctuated by the abandonment of intepirdine for Alzheimer’s disease—in development at its Axovant company—and disappointing data for nelotanserin in Lewy body dementia (LBD) and Parkinson’s disease dementia.



The group is showing no signs of stopping its harvesting of new candidates, however, snapping up an antibiotic and drug for diabetes in the last few weeks alone.