Thorough QT study of the effect of fesoterodine on cardiac repolarization

Fesoterodine 4 mg and 8 mg once daily are indicated for the treatment of overactive bladder. A thorough QT study was conducted to investigate the effects of fesoterodine on cardiac repolarization.

In this parallel-group study, subjects were randomly assigned to receive double-blind fesoterodine 4 mg, fesoterodine 28 mg, or placebo or open-label moxifloxacin 400 mg (positive control) for 3 days. Electrocardiograms (ECGs) were obtained on Days -1 (baseline), 1, and 3. The primary analysis was the time-averaged changes from baseline for Fridericia's-corrected QT interval (QTcF) on Day 3.

Among 261 subjects randomized to fesoterodine 4 mg (n = 64), fesoterodine 28 mg (n = 68), placebo (n = 65), or moxifloxacin 400 mg (n = 64), 256 completed the trial. The least squares mean changes in QTcF from baseline were 21.1, 20.5, 18.5, and 31.3 ms (maximum), and -5.1, -4.2, -5.2, and 7.6 ms (time-averaged at Day 3) for placebo, fesoterodine 4 mg, fesoterodine 28 mg, and moxifloxacin, respectively. The lower limit of the 95% confidence interval exceeded 5 ms for moxifloxacin.

The results indicate that fesoterodine is not associated with QTc prolongation or other ECG abnormalities at either therapeutic or supratherapeutic doses.