Overactive Bladder Syndrome: Incobotulinumtoxin Versus Onabotulinumtoxin

The aim of the original study was to compare Incobot/A versus Onabot/A in order to evaluate if the differences in the pharmacologic formulations between the two drugs could affect their efficacy and safety in the treatment of neurogenic overactive bladder (OAB). In the original study protocol two different dosages for either Incobot/A and Onabot/A (200 U and 100 U) were considered, to treat patients with neurogenic detrusor overactivity incontinence performing intermittent catheterization (IC) with higher dosages and those able to void spontaneously with lower dosage, with the resulting four treatment groups. For such a study, a very large sample of participants should have been treated and followed up, to have adequate power to demonstrate the hypothesis. At the end of last February 2020, we had to temporarily stop all the clinical activities related to the study and patients' recruitment, due to the occurrence of Sars-Cov-2 pandemic in our Country. At that point, a non-inferiority study seemed to be possible and adequate, and we adapted the protocol accordingly. In addition, on the basis of previously published information, we could hypothesize that the new drug (Incobot/A) would have had at least a roughly similar effect to the control drug (Onabot/A). In order to perform a non-inferiority study, the power and sample size analysis have been re-planned. Thus, we perform a not planned interim analysis to show the preliminary results of an ongoing, non-inferiority trial in which patients' recruitment temporarily stopped due to incontrollable external factors. The present study will be aimed to assess the non-inferiority of Incobot/A compared to Onabot/A on the efficacy and safety parameters, in the treatment of patients with refractory NDOI performing IC, who are randomized to receive 200 U of Incobot/A or Onabot/A intradetrusor injections and who are followed up to 12 wks after treatment