Trospium chloride once-daily extended release is effective and well tolerated for the treatment of overactive bladder syndrome: an integrated analysis of two randomised, phase III trials.
BACKGROUND
Trospium chloride is an antimuscarinic agent with a hydrophilic polar quaternary amine structure that is minimally metabolised by hepatic cytochrome P450 and is actively excreted in the urine, each of which confers a potential benefit with regard to efficacy and tolerability.


OBJECTIVE
We analysed pooled data from two identically designed phase III trials of a once-daily, extended-release (XR) formulation of trospium chloride (trospium XR 60-mg capsules) in subjects with overactive bladder syndrome (OAB).


METHODS
Adults with OAB of > or = 6 months' duration with urinary urgency, frequency and > or = 1 urge urinary incontinence (UUI) episode/day were enrolled in these multicentre, parallel-group, double-blind trials. Participants were randomised (1 : 1) to receive trospium XR 60 mg or placebo for 12 weeks. Primary efficacy variables were changes in urinary frequency and the number of UUI episodes/day. Adverse events (AEs) were recorded throughout.


RESULTS
In total, 1165 subjects were randomised (trospium XR, 578; placebo, 587). At baseline, subjects averaged 12.8 toilet voids/day and 4.1 UUI episodes/day. Compared with placebo, subjects treated with trospium XR had significantly greater reductions from baseline in the mean number of toilet voids/day (-1.9 vs. -2.7; p < 0.001) and UUI episodes/day (-1.8 vs. -2.4; p < 0.001) at week 12. The most frequent AEs considered possibly related to study treatment were dry mouth (trospium XR, 10.7%; placebo, 3.7%) and constipation (trospium XR, 8.5%; placebo, 1.5%). Notably, rates of central nervous system (CNS) AEs were lower with trospium XR vs. placebo (dizziness: 0.2% vs. 1.0%; headache: 1.4% vs. 2.4%).


CONCLUSIONS
Treatment with trospium XR resulted in statistically significant improvements in both of the dual primary and all of the secondary outcome variables. Trospium XR demonstrated favourable rates of AEs, particularly CNS AEs (numerically lower than with placebo) and dry mouth (lower than previously reported with trospium immediate-release, although not compared in a head-to-head study).
Staskin
D R
DR
Division of Urology, Caritas-St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, MA 02135, USA. staskinatt@gmail.com
Rosenberg
M T
MT
Sand
P K
PK
Zinner
N R
NR
Dmochowski
R R
RR
D001561:Benzilates; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018727:Muscarinic Antagonists / Q000008:administration & dosage* / Q000009:adverse effects; D009662:Nortropanes / Q000008:administration & dosage* / Q000009:adverse effects; D016896:Treatment Outcome; D053201:Urinary Bladder, Overactive / Q000188:drug therapy*
D001561:Benzilates; D003692:Delayed-Action Preparations; D018727:Muscarinic Antagonists; D009662:Nortropanes; C003330:trospium chloride