Objective: To compare the efficacy of two types of botulinum toxin type A (BTX-A; Dysport, Ipsen Ltd, Slough, UK) or Botox (Allergan Inc., Irvine, CA, USA) and examine the possible dose-effect relation for Dysport in those patients, as multifocal detrusor injections with BTX-A are effective for severe neurogenic detrusor overactivity in adults.
Patients and methods: This was an open-label, observational case-control study comparing Dysport and Botox, and the dose-effect relation for Dysport. The patients included were treated with either Dysport (cases; 500, 750, or 1000 IU), or with Botox (controls: 300 IU, and exceptionally 200 or 400 IU). The continence volume (primary), mean and maximum catheterized volume, and antimuscarinic use were assessed, and cystometric variables measured were overactivity volume (primary), detrusor compliance, and cystometric capacity. All variables were assessed at baseline, 3 and 9 months after treatment, and results analysed using analysis of variance (paired) t-tests, chi-square tests and regression analysis.
Results: There were 28 cases and 28 matched controls; their demographic characteristics, bladder management, and baseline values were comparable between the groups. At 3 months there was a significant improvement in cystometric variables and continence volume in both groups, but in mean catheterized volume and reduced use of antimuscarinics in cases only. At 9 months there was no significant improvement over baseline except for the continence volume in the cases. There were no significant differences in results between the groups except for the continence volume at 3 months (459 mL after Dysport and 396 mL after Botox; P=0.015). There was no dose-related response for Dysport at 3.8 months of follow-up. The interval between injections (9.5, 14.5 and 16.1 months for Dysport 500, 750, and 1000 IU; 10.1 months for Botox) was not significant. There were nine non-responders in the Dysport group and seven in the Botox group; the patient characteristics and baseline data were comparable to those of the responders. There was transient hypoasthenia in one of the responders (750 IU Dysport).
Conclusions: A single treatment session with either Dysport or Botox in a setting combined with antimuscarinics might improve the patient's condition for up to a year. There was no clear dose-related effect for Dysport in adults.