MSN Labs Receives Regulatory Approval for Phase III Trial of Vibegron 75 mg in Overactive Bladder
Key Insights
MSN Labs (search) secured regulatory approval from India's Subject Expert Committee (SEC) to conduct a Phase III clinical trial comparing vibegron 75 mg with mirabegron in overactive bladder (search) patients.
The approved trial protocol excludes patients with refractory overactive bladder (search), focusing on a more targeted patient population for efficacy assessment.
Vibegron is a selective beta-3 adrenergic receptor (search) agonist that increases bladder capacity by relaxing detrusor smooth muscle, already approved in Japan and the US.
MSN Labs (search) has received regulatory approval from India's Central Drugs Standard Control Organisation (CDSCO (search)) Subject Expert Committee (SEC) to proceed with a Phase III clinical trial of vibegron 75 mg for overactive bladder (search) (OAB) treatment. The approval, granted during a committee meeting on September 18, 2025, follows the company's submission of a revised trial protocol that addresses earlier regulatory recommendations.
Trial Design and Protocol
The approved Phase III study is titled "A Phase-III, Randomized, Open-Label, Active-Controlled, Multicentre Study to Evaluate the Safety and Efficacy of Vibegron 75 mg Tablet, in Comparison with Mirabegron ER 25 mg/50 mg Tablet in Patients with Overactive Bladder (search) (OAB)" (Protocol No. 003/VIB/MSN/2024, Version 2.0, dated July 12, 2025).
The trial design represents a head-to-head comparison between vibegron and mirabegron ER, with mirabegron serving as the active control. Mirabegron is already marketed in India and globally for OAB treatment, making it an appropriate reference standard for efficacy and safety comparison.
Regulatory Conditions and Patient Population
A key condition of the SEC approval requires the exclusion of patients with refractory overactive bladder (search) from the trial population. This exclusion criterion ensures a more focused assessment of treatment outcomes in the target patient population and follows detailed committee deliberation on the revised proposal.
The decision to exclude refractory OAB patients represents a strategic approach to generate robust data for potential regulatory submission by concentrating on patients most likely to respond to treatment.
Mechanism of Action and Clinical Background
Vibegron is a potent, selective beta-3 adrenergic receptor (search) (β3) agonist that works by relaxing the detrusor smooth muscle of the bladder, thereby increasing bladder capacity. The drug is being developed to treat patients with OAB presenting with symptoms of urge urinary incontinence (search), urgency, and increased urinary frequency.
The therapeutic approach targets the underlying pathophysiology of overactive bladder (search) by modulating bladder muscle function through selective β3-adrenergic receptor activation.
International Regulatory Status
Vibegron has established regulatory precedent in major markets. The drug was first approved in Japan in September 2018 for overactive bladder (search) treatment, addressing the condition's distressing symptoms of urge urinary incontinence (search), urgency, and urinary frequency, which significantly impact patient quality of life. Subsequently, on December 23, 2020, vibegron received approval for the same indication in adults in the United States.
Clinical Development Timeline
The current approval follows MSN Labs (search)' submission of a revised clinical trial protocol, developed in response to an earlier SEC recommendation dated April 17, 2025. The protocol revision process demonstrates the company's commitment to addressing regulatory feedback and optimizing trial design for successful execution.
The Phase III trial will generate comprehensive safety and efficacy data comparing vibegron 75 mg with mirabegron ER 25 mg/50 mg, providing the foundation for potential market authorization in India's overactive bladder (search) treatment landscape.