Evaluating the Effect of Incobotulinumtoxin A for Glabellar, Forehead, and Crow's Feet Lines Using A High Dilution.

Background: As aesthetic preferences have evolved and patients wish their muscles to be relaxed, but not frozen, a higher dilution of incobotulinumtoxinA (INCO) has allowed for increased spread using fewer units, yet no studies to date have investigated the efficacy, longevity, and safety of hyperdiluted INCO.

Objective: We evaluated the effect of incobotulinumtoxinA (INCO) in glabellar, forehead, and lateral periorbital lines using a high dilution.

Methods: Subjects with moderate-to-severe upper facial lines at rest according to the Merz Aesthetics Scales (Merz Pharmaceuticals GmbH, Frankfurt am Main, Germany) received 15U of INCO to the glabellar (n=4 injection sites), 10U to the rest of the forehead (n=10 injection sites), and 5U to the lateral periorbital lines (n=3 injection sites/eye). Primary outcomes were physician- and subject-rated improvement at one month using the Global Aesthetic Improvement Scale (GAIS) and changes in line severity using the Merz Aesthetics Scales.

Results: The study included 15 women aged 35 to 65 years. At one month, physician GAIS scores indicated 91.2% of subjects were very much improved and 8.8% were much improved; 91.5%, 78.0%, and 57.6% of participants remained at least improved at four, five, and six months, respectively. Subject GAIS scores at one month were in agreement with physician scores. At one month, an improvement of at least one point in Merz Aesthetics Scales scores in glabellar, forehead, and lateral periorbital lines was reported in 88.9%, 98.3%, and 94.8% of participants, respectively. Subject satisfaction was high throughout the study. No treatment-related adverse events were observed.

Conclusion: Hyperdilute INCO was effective at improving overall appearance and reducing line severity in individuals with moderate-to-severe upper facial lines. Patient satisfaction was maintained up to six months and treatment was well tolerated.