Solifenacin shows superior tolerability compared to oxybutynin immediate-release (IR)
Canadian study (VECTOR) presented at the 2009 American Urological Association Annual Meeting
The VECTOR study compared the tolerability of solifenacin versus oxybutynin IR for the treatment of OAB. A secondary objective was to assess the efficacy of solifenacin versus oxybutynin IR for the treatment of OAB.
“Findings from the VECTOR study are very encouraging,” said Sender Herschorn, MDCM, FRCSC, Professor and Chair of the Division of Urology at the
Patients in the VECTOR study were adults over the age of 18 with OAB symptoms for (greater than or equal to) 3 months (urgency with or without urinary incontinence, usually with frequency and nocturia) and as documented in a 3-day patient diary: (greater than) 1 urge episode/24 hours (average) as well as (greater than or equal to) 8 micturitions/24 hours (average). Overall, 132 patients were recruited from 12 Canadian sites.
In this multi-centre, prospective, randomized, double-blind, double-dummy, 8 week study, solifenacin was associated with a superior tolerability profile compared to oxybutynin IR. Patients on solifenacin experienced a 48 per cent lower incidence of dry mouth and a lower severity of dry mouth, of which 75 per cent were mild, compared with patients taking oxybutynin IR (p=0.001). The findings also revealed significantly fewer withdrawals due to dry mouth as well as fewer overall adverse events (p=0.009), and fewer treatment related adverse events (p=0.0093) compared to oxybutynin IR. Both solifenacin and oxybutynin IR improved OAB symptoms and Patient-Reported Outcomes.
Solifenacin, a competitive muscarinic receptor antagonist, has not had its side effect profile directly compared with oxybutynin IR until this study. “It is hoped that these study results will make more people aware of a better tolerated treatment choice,” said Herschorn.
OAB is a chronic medical condition that is characterized by the sudden, involuntary and sometimes uncomfortable need to urinate any time during the day or night. OAB occurs when the bladder’s smooth muscle squeezes while the bladder is still filling instead of when it is completely full, sending a signal to the brain that results in the urge to urinate. The condition is associated with poor quality of life that may result in significant social, psychological, occupational, domestic and physical stigmas. It is estimated that 12 to 18% of Canadians suffer from OAB.
Vesicare(R) (Solifenacin Succinate) is a once-daily oral medication and is indicated for the treatment of overactive bladder in adults with symptoms of urinary urgency, urge urinary incontinence, and urinary frequency. It is not indicated for the management of stress incontinence, which can occur when the bladder leaks urine during exercise, coughing, or sneezing.(1) Vesicare has high affinity for muscarinic receptors in the bladder, which control the detrusor muscle and cause it to relax. This allows the bladder to fill normally and reduces the sense of urgency that a patient feels. In clinical studies, the most common side effects reported with Vesicare were dry mouth and constipation. Patients may also experience dry eyes, urinary retention, and blurred vision. Vesicare was approved by Health Canada in
About Astellas Pharma Canada, Inc.
Astellas Pharma Canada, Inc. is highly focused on customers and their needs and is committed to making a difference in urology. The company also seeks to develop breakthrough products in infectious disease, immunology, dermatology and cardiovascular disease. Astellas Pharma Canada, Inc. is one of the Astellas Group of companies in
------------------------- (1) Vesicare Product Monograph, as at July 24, 2008
SOURCE Astellas Pharma Canada, Inc.