Darifenacin Effectively Relieves Symptoms In Patients Regardless of Baseline Severity of Overactive Bladder (OAB)

Introduction and Objectives

Severity of OAB symptoms (Sx) eg incontinence episodes (IEs), urgency, frequency and nocturia varies between pts.

It is of interest to see if pts respond differently to OAB therapy according to Sx severity. Data from 3 fixed dose darifenacin (DAR) phase 3 studies1 were analyzed for subgroups differing in BL severity.

Methods

Data were pooled from 3 12 wk, double blind studies of 1053pts (19 88y, 85% women) randomized to DAR 7.5/ 15mg once daily or matched placebos (PBO). Predetermined efficacy variables were analyzed retrospectively for pts with mild/moderate (M/M) OAB (<21 IEs/wk at BL) or severe OAB (≥21 IEs/wk). Variables included absolute and % change from baseline at 2, 6, 12wks and last observation carried forward (LOCF) in voids/d, mean volume/void, urgency (pressure to void) episodes/d, and IEs/wk. Non parametric statistical methods were applied.

Results

DAR 7.5/15mg significantly improved OAB Sx vs PBO in pts with M/M OAB. Sx also improved in pts with severe OAB, especially with 15mg. Improvements as early as 2wks were sustained through 12wks for urgency episodes/d and IEs/wk (Table 1), with similar trends for voids/d and mean volume/void (data not shown). The most common AEs were dry mouth (20.2, 35.3 and 6.2%) and constipation (14.8, 21.3 and 6.2%) for DAR 7.5 and 15mg and PBO (total population), respectively1

Table 1: Median absolute (%) changes from BL to timepoints


*p<0.05; †p≤0.01; ‡p≤0.001 for treatment difference vs PBO (Wilcoxon Rank Sum Test).

Conclusions

Fixed dose DAR effectively relieves OAB regardless of BL severity (M/M/severe), with improvement within 2wks. DAR 15mg was also effective for pts with severe OAB, confirming dose titration as important for individual pts’ sensitivity and disease severity.

Keywords

Bladder hyperactivity; anticholinergics; clinical trial

1Chapple et al. BJU Int 2005.