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

OBJECTIVE

To explore the dose equivalence ratio and treatment costs for abobotulinumtoxinA and incobotulinumtoxinA for patients with focal dystonias.

DESIGN

Patient chart review.

SUBJECTS/PATIENTS: 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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.