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.