Long-term follow-up reveals a low persistence rate of abobotulinumtoxinA injections for idiopathic overactive bladder

Summary Introduction Little is known about long-term efficacy and tolerance of intra-detrusor injections of abobotulinumtoxinA for management of idiopathic overactive bladder (OAB). We report long-term efficacy and compliance of abobotulinumtoxinA in patients treated for OAB. Methods All patients treated with abotulinumtoxinA for OAB in a tertiary reference centre between 2005 and 2012 were included in a retrospective analysis. Patients received 150, 250 or 500 U of abotulinumtoxinA as first injection. The primary endpoint was the discontinuation rate at 5 years. Other outcomes of interest were: rate of failure, reasons for discontinuation and subsequent treatment elected in those who did not persist with abobotulinumtoxinA. Results Fifty-nine patients (50 women and 9 men) were included. Forty-one patients (69.4%) received 250 U of abobotulinumtoxinA as first injection. Thirteen patients (22%) received 500 U and 5 (8.4%) received 150 U of BoNT-A. Median follow-up was 83.6 months [0.3–183.6]. Median number of injections per patient was 2 [1–15] and median reinjection interval was 10.7 [3–86.4] months. The estimated 5-year discontinuation-free survival rate was 23.4%. Fourteen patients (23.7%) experienced persistent improvement of symptoms and 12 patients (20.3%) stopped the injections because of tolerability issues. Main cause of discontinuation was primary failure, which occurred in 21 patients (35.5%). Conclusion Overall, 59.3% of patients were successfully treated with first abobotulinumtoxinA injection. Although the estimated 5-year discontinuation-free survival rate is low, abobotulinumtoxinA could be considered as an alternative off-labelled in patients not responders to onabotulinumtoxinA after failure of other conservative measures. Level of proof 3.