A multicentre, prospective, randomised, double-blind study to measure the treatment effectiveness of abobotulinum A (AboBTXA) among women with refractory interstitial cystitis/bladder pain syndrome

Introduction and hypothesis To determine if abobotulinumtoxin A (AboBTXA) is an effective treatment for interstitial cystitis/bladder pain syndrome (IC/BPS). Methods We performed a double-blind study of 54 women with severe, refractory IC from three referral centres whom we randomly allocated to treatment with hydrodistension + injection of normal saline or to hydrodistension + injection with AboBTXA. The O'Leary-Sant questionnaire consists of problem (OLS-PI) and symptom (OLS-PI) index scores, and bladder diary data were compared between AboBTXA and control patients at baseline and at 3 months of follow-up. Measurements were made beyond 3 months, but no further randomised comparison was possible due to the ability of nonresponsive patients in either group to have AboBTXA treatment. Results Complete data were available in 50 patients, and in both groups, OLS questionnaires showed improvement at 3 months. Only the OLS-PI was improved in the AboBTXA group (p = 0.04). At 3 months, no difference was found in either OLS-SI or total OLS score. Twelve patients had urinary tract infection (UTI) treated during the follow-up period, which confounded results. In the 38 patients without UTI, there was improvement in total OLS score (p = 0.02), OLS-PI (0.08), and OLS-SI (p = 0.008) for the AboBTXA group at 3 months. Only five AboBTXA compared with two control patients had a 50 % reduction in OLS score. Conclusions For chronic refractory IC/BPS patients, AboBTXA was associated with no overall improvement in total OLS score, although significant benefit was noted in a small number of patients. The absence of posttreatment UTI was associated with a better response to AboBTXA.