Solifenacin Works for Difficult OAB
PARIS—Patients with severely bothersome overactive bladder (OAB) symptoms who have failed treatment with tolterodine ER may benefit by switching to solifenacin, research suggests.
At the Société Internationale d'Urologie 29th Congress here, Norman Zinner, MD, a urologist and medical director of Western Clinical Research, Inc. in Torrance, Calif., presented the results of a 12-week, open-label study that examined solifenacin's efficacy and tolerability in patients with OAB for at least three months who had taken tolterodine ER 4 mg for at least four weeks without sufficient improvement in urinary urgency. Inclusion criteria required that patients have a mean of at least three urgency episodes per day while taking tolterodine.
After a 14-day washout period, patients started on solifenacin 5 mg/day, with a flexible dose
option of 5 to 10 mg/d at weeks 4 and 8. Of the 440 patients enrolled in the trial for whom complete data were available, 165 had severe symptoms.
The presence of severe symptoms was defined by high bother at pre-washout, referring to a score of at least 5 on the Patient Perception of Bladder Condition (PPBC) scale. The primary efficacy measure was an improvement in urgency episodes per day at week 12 compared with pre-washout levels when patients were receiving tol-terodine ER 4 mg.
Patients receiving either dose of solifenacin had significant improvements in urgency episodes and all other efficacy variables from pre-washout to the end of the trial. The median change from pre-washout for the severe cohort was as follows: 72.2% for urgency episodes, -15.0% for micturition frequency, -92.9% for incontinence episodes, -45.5% for nocturia, and -38.5% for nocturnal voids.
Significant improvements were also observed for all efficacy parameters from post-washout when tolterodine ER had been stopped. The median change from post-washout for the severe cohort was -75.0% for urgency, -22.2% for micturitions, 92.9% for incontinence, -50.0% for nocturia, and
-37.5% for nocturnal voids.
At the end of the trial, 28% of the severe cohort reported no or very minor symptoms (PPBC score of 1 or 2), 19% described some minor symptoms (PPBC score of 3), and 28% cited some moderate symptoms (PPBC score of 4).
In addition, significant improvements were recorded in all domains assessed in a patient questionnaire including bother, coping, concern, sleep, and health-related quality of life subscales. About two thirds of patients in the severe cohort developed treatment-related adverse effects, which usually were mild to moderate and mainly related to anticholinergic side effects.
According to Dr. Zinner, “Treatments for OAB should offer satisfactory efficacy to patients irrespective of symptom severity. In patients whose ‘severely bothersome' OAB symptoms are not relieved by tolterodine ER, 4 mg, solifenacin at either 5 or 10 mg doses was shown to re-duce OAB symptoms and improve symptom bother and health-related quality of life.”