Patient-Centric Dose Equivalency Pilot Study of Incobotulinumtoxin A (Xeomin) Vs. Abobotulinumtoxin A (Dysport) in the Treatment of Glabellar Frown Lines

Friday, April 12, 2013
Jonathan Bank, MD, Section of Plastic and Reconstructive Surgery, Department of Surgery, University of Chicago Medical Center, Chicago, IL, Nicole Phillips, MD, Plastic Surgery, Brigham and Women's Hospital, Boston, MA and Laurie Casas, MD, Plastic Surgery, NorthShore University HealthSystem, Glenview, IL
Goals/Purpose: Incobotulinumtoxin A (Xeomin) has been proposed as an alternative to abobotulinumtoxin A (Dysport) and andonabotulinumtoxin A (Botox) in the treatment of glabellar frown lines. A recent study comparing Dysport and Botox revealed equivalent efficacy with a dose conversion ratio of 2.5:1[1]. We sought to establish effectiveness and dosing equivalency of Xeomin vs. Dysport.

Methods/Technique: Inclusion criteria for this pilot study included patients of a single surgeon that had previously received a constant dose of Dysport over at least four consecutive treatment sessions to achieve 85-90% elimination of dynamic glabellar frown lines. The primary outcome sought was dose comparison between established maintenance Dysport dosing and Xeomin first time dosing. A 2:1 conversion (Dysport:Xeomin) was chosen in most patients. Secondary outcomes were patient-reported onset of effect, physician-assessed effect at 10-12 weeks, pain associated with administration, and need for re-treatment.

Results/Complications: A total of 32 subjects were included. The mean dose of Xeomin was 17.1 units (±6.1, median dose 20 units). The mean dose of Dysport was 27.6 (±11.7, median dose 27.5 units). The mean difference in treatment units was -10.5 (95% CI, p < 0.001). Among 30 patients who reported effect onset, the median was 8.5 days, with a range of 1-14. At 10-12 weeks, muscle paralysis was assessed to be 69.2% (±27.3), vs. 90.3%(±1.8) with Dysport (p<0.001). The majority of patients rated pain of administration as equal or greater to that of Dysport (63% and 22%, respectively). Three patients (9%) required re-treatment at two weeks with Dysport due to lack of effective treatment with Xeomin.

Conclusion: We found Xeomin at 17.1(±6.1) units to be less effective than Dysport at 27.6(±11.7) units in the treatment of glabellar frown lines at 10-12 weeks post-administration. Dosing was less predictable than dosing associated with Dysport treatment. Larger, randomized controlled trials are indicated to further delineate these differences.