Switch from abobotulinumtoxinA (Dysport®) to incobotulinumtoxinA (Xeomin®) botulinum toxin formulation: a review of 257 cases.

Abstract

To explore the dose equivalence ratio and treatment costs for abobotulinumtoxinA and incobotulinumtoxinA for patients with focal dystonias. Patient chart review. Adult patients with blepharospasm (n = 19), cervical dystonia (n = 122), hemifacial spasm (n = 91) or segmental/generalized dystonia (n = 19) at a neurology outpatient clinic. Patients were switched from established abobotulinumtoxinA therapy to incobotulinumtoxinA at a ~4:1 unit ratio. Dose requirements, injection intervals, treatment efficacy, and adverse events were evaluated for a period of ≥ 1 year. Patients were switched from abobotulinumtoxinA to incobotulinumtoxinA with a mean dose ratio of 4.07 (standard deviation (SD) 0.50). After switching, incobotulinumtoxinA dose requirements remained stable; the mean (SD) dose ratio at the end of the review period (52-219 weeks after switching) was 3.89 (SD 0.58). Injection intervals also remained stable after switching. Adverse events were injection site pain (n = 45) and bruising (n = 4). Five patients (2.0%) discontinued incobotulinumtoxinA treatment: 4 stopped receiving injections, and 1 reverted to abobotulinumtoxinA. Switching to incobotulinumtoxinA reduced the mean toxin expenditure to 76.7% of the cost of abobotulinumtoxinA. For patients with conditions commonly treated in dystonia clinics, switching from abobotulinumtoxinA to incobotulinumtoxinA, given at equivalent doses (~4:1 unit ratio) at similar intervals, was effective, well tolerated and achieved cost savings.