Astellas Pharma Inc. announced that the US Food and Drug Administration (FDA) has approved a supplemental New Drug Application (sNDA) for the use of mirabegron in combination with the muscarinic antagonist solifenacin succinate for the treatment of overactive bladder (OAB) with symptoms of urge urinary incontinence, urgency and urinary frequency.

In the United States, mirabegron and solifenacin succinate are marketed as Myrbetriq and VESIcare, respectively. Each is approved by the FDA as a monotherapy for OAB.“OAB patients may have symptoms that are not fully managed with their current treatment," said Carol Schermer, M.D., M.P.H., senior medical director, urology, Astellas. "With the FDA approval of Myrbetriq in combination with solifenacin succinate, Astellas is able to offer an additional treatment option to individuals living with symptoms of OAB."

The sNDA submission was based on data from the global phase 3 SYNERGY I, SYNERGY II and BESIDE studies. These studies evaluated combination therapy with mirabegron and solifenacin succinate compared with each drug as monotherapy or placebo.

The phase 3 SYNERGY I trial enrolled 6,991 patients across 435 study locations in 42 countries. The trial evaluated the safety profile of combinations of mirabegron and solifenacin succinate compared with each drug as monotherapy and placebo in patients who had experienced symptoms of "wet" OAB (urinary frequency and urgency with incontinence) for at least 3 months.

The 52-week, phase 3 SYNERGY II trial enrolled 2,084 patients across 251 sites in 32 countries. The trial evaluated the long term safety profile of combination of mirabegron 50 mg and solifenacin succinate 5 mg compared with each drug as monotherapy in patients who had experienced symptoms of "wet" OAB (urinary frequency and urgency with incontinence) for at least 3 months.

The phase 3b BESIDE study enrolled 2,174 patients across 281 sites in 31 countries. The trial evaluated the efficacy, safety and tolerability of mirabegron 50 mg as an add-on therapy with solifenacin succinate 5 mg versus solifenacin succinate 5 mg and 10mg alone in OAB patients who had inadequate response to treatment with solifenacin succinate monotherapy.

Overactive bladder is a urine storage problem of urgency, with or without urge urinary incontinence (leakage), often with urinary frequency and nocturia. It has been estimated by this year, 546 million people worldwide will be affected by OAB. For people with OAB, inappropriate signals are sent to the muscles in the bladder causing them to contract before the bladder is full. These bladder contractions may cause strong, sudden urges, and a frequent need to go to the bathroom.

Myrbetriq (mirabegron), a beta-3 adrenergic agonist, is indicated as monotherapy or in combination with the muscarinic antagonist solifenacin succinate for the treatment of overactive bladder (OAB) with symptoms of urge urinary incontinence, urgency, and urinary frequency.